Parastoo Sadeghi - Publications


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	2011


	JOURNALS AND MAGAZINES:


	61)	F. Tabataba, P. Sadeghi and M. Pakravan, "Outage probability and power allocation of amplify and forward relaying with channel estimation errors," IEEE Trans. Wireless Commun., pp. 124-134, Jan. 2011. PDF \| bibtex
		@article{tabataba:sadeghi:pakravan:twc:11, Author = "Tabataba, F. and Sadeghi, P. and Pakravan, M.", Date-Modified = "2011-01-21 11:43:26 +1100", Doi = "10.1109/TWC.2010.102810.091729", Era-Rank = "A", Google-Scholar = "0", Journal = "{IEEE} Trans. Wireless Commun.", Link = "papers/2011/TWC_2011.pdf", Linkname = "PDF", Month = jan, Number = "1", Pages = "124-134", Rating = "4", Status = "Published", Title = "Outage Probability and Power Allocation of Amplify and Forward Relaying with Channel Estimation Errors", Volume = "10", Year = "2011", Abstract = "This paper studies the statistical properties of the signal-to-noise ratio (SNR) of the dual-hop relaying link in a cooperative wireless communication system in the presence of channel estimation errors for fixed-gain (FG) and variable-gain (VG) relays. The SNR expression is derived and three different analytical approaches with different simplifying assumptions are proposed to obtain the probability distribution function of the SNR and the outage probability in each mode. All but one approach result in closed-form expressions for the outage probability. The simplest approach in each mode has been used to find an optimum power allocation scheme for pilot and data symbols transmission at the source and the relay that results in minimizing the outage probability. Numerical analysis is used to confirm the accuracy of the derived theory and to show that the analytical approaches have a good outage performance, especially as the relay-destination distance increases. It is shown that significant power savings (e.g. 6 dB in VG mode) can be obtained by using the proposed power optimization method.", };


	60)	T. A. Lamahewa, P. Sadeghi and X. Zhou, "On lower bounding the information capacity of amplify and forward wireless relay channels with channel estimation errors," IEEE Trans. Wireless Commun. (accepted for publication 10/02/2011), 2011. PDF \| bibtex
		@article{lamahewa:sadeghi:zhou:twc:11, Author = "T. A. Lamahewa and P. Sadeghi and X. Zhou", Date-Modified = "2011-01-21 11:43:26 +1100", Era-Rank = "A", Google-Scholar = "0", Journal = "{IEEE} Trans. Wireless Commun. (accepted for publication 10/02/2011)", Year = "2011", Rating = "4", Status = "Accepted for Publication", Title = "On Lower Bounding the Information Capacity of Amplify and Forward Wireless Relay Channels with Channel Estimation Errors", };


	CONFERENCES:


	59)	M. Yu and P. Sadeghi, "Time domain synchronization and decoding of P1 symbol in DVB-T2," Proc. IEEE Int. Conf. Acoust., Speech, Signal Processing, ICASSP'2011, Prague, Czech Republic, 2011. Preprint \| bibtex
		@inproceedings{yu:sadeghi:icassp:11, Address = "Prague, Czech Republic", Author = "M. Yu and P. Sadeghi", Booktitle = "Proc. IEEE Int. Conf. Acoust., Speech, Signal Processing, ICASSP'2011", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 12:09:38 +1100", Era-Rank = "B", Google-Scholar = "0", Month = "May", Rating = "3", Status = "Accepted for Publication 18 January (3828)", Title = "TIME DOMAIN SYNCHRONIZATION AND DECODING OF {P1} SYMBOL IN {DVB-T2}", Year = "2011", Abstract = "In this paper we propose a novel timing and frequency synchronization and decoding method for the P1 symbol in DVB-T2 based on the correlation between the received signal and the time domain P1 symbols. This method does not require post-FFT decoding and is insensitive to the frequency-shift offset and continuous-wave (CW) interference. The performance of the proposed method is evaluated via computer simulations, which shows that not only does it achieve good synchronization performance, but also it provides a decoding SNR gain of at least 6dB in AWGN channel and at least 2dB in multipath Rayleigh fading channel compared with the performance reported in the standard guidelines.", };


	58)	Z. Khalid, S. Durrani, R. A. Kennedy and P. Sadeghi, "On the construction of low-pass filters on the unit sphere," Proc. IEEE Int. Conf. Acoust., Speech, Signal Processing, ICASSP'2011, Prague, Czech Republic, 2011. Preprint \| bibtex
		@inproceedings{khalid:durrani:kennedy:sadeghi:icassp:11, Address = "Prague, Czech Republic", Author = "Khalid, Z. and Durrani, S. and Kennedy, R. A. and Sadeghi, P.", Booktitle = "Proc. IEEE Int. Conf. Acoust., Speech, Signal Processing, ICASSP'2011", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 12:09:38 +1100", Era-Rank = "B", Google-Scholar = "0", Month = "May", Pdf-Url = "http://users.rsise.anu.edu.au/~rod/papers/preprint/Kennedy_CS2011_ICASSP_Zubair.pdf", Rating = "3", Status = "Accepted for Publication 18 January (3828)", Title = "On the Construction of Low-Pass Filters on the Unit Sphere", Year = "2011", Abstract = "This paper considers the problem of construction of low-pass filters on the unit sphere, which has wide ranging applications in the processing of signals on the unit sphere. We propose a design criterion for the construction of strictly bandlimited low-pass filters in the spectral domain with optimal concentration in the specified polar cap region in the spatial domain. Our approach uses the weighted sum of the first optimally concentrated eigenfunctions from appropriately formulated Slepian concentration problems on the sphere. Furthermore, in order to reduce the computational complexity of the proposed algorithm, we develop a closed-form expression to accurately model these eigenfunctions. We illustrate the construction of low-pass filters using the proposed approach and demonstrate the advantage of our method approach compared to a diffusion based approach in the literature in terms of control over both bandwidth in the spectral domain and concentration in the spatial domain.", };


	57)	A. Fu and P. Sadeghi, "R-regular P2P broadcast networks: optimal delay and throughput using network coding," Proc. IEEE Int. Conf. Commun. (ICC) (to appear), Kyoto, Japan, June 2011. Preprint \| bibtex
		@inproceedings{fu:sadeghi:icc:11, Address = "Kyoto, Japan", Author = "Fu, A. and Sadeghi, P.", Booktitle = "Proc. {IEEE} Int. Conf. Commun. (ICC) (to appear)", Date-Modified = "2011-01-21 12:10:36 +1100", Era-Rank = "B", Google-Scholar = "0", Month = jun, Rating = "3", Status = "Accepted for Publication", Title = "r-Regular {P2P} Broadcast Networks: Optimal Delay and Throughput Using Network Coding", Year = "2011", };


	56)	C. Hucher and P. Sadeghi, "Using distributed rotations for a low-complexity dynamic decode-and-forward relay protocol," Proc. IEEE Int. Conf. Commun. (ICC) (to appear), Kyoto, Japan, June 2011. Preprint \| bibtex
		@inproceedings{hucher:sadeghi:icc:11, Address = "Kyoto, Japan", Author = "Hucher, C. and Sadeghi, P.", Booktitle = "Proc. {IEEE} Int. Conf. Commun. (ICC) (to appear)", Date-Modified = "2011-01-21 12:10:55 +1100", Era-Rank = "B", Google-Scholar = "0", Month = jun, Rating = "3", Status = "Accepted for Publication", Title = "Using Distributed Rotations for a Low-Complexity Dynamic Decode-and-Forward Relay Protocol", Year = "2011", };


	55)	X. Zhou, P. Sadeghi, T. A. Lamahewa and A. Hjorungnes, "Optimal flashy transmission in training-based MISO TDD systems," Proc. 2011 Australian Commun. Theory Workshop (AusCTW), Melbourne, Australia, Feb. 2011, pp. 25-30. Preprint \| bibtex
		@inproceedings{zhou:sadeghi:lamahewa:Hjorungnes:ausctw:11, Address = "Melbourne, Australia", Author = "Zhou, X. and Sadeghi, P. and Lamahewa, T. A. and Hjorungnes, A.", Booktitle = "Proc. 2011 Australian Commun. Theory Workshop {(AusCTW)}", Date-Modified = "2011-01-21 12:10:41 +1100", Era-Rank = "-", Google-Scholar = "0", Month = feb, Rating = "1", Pages = "25-30", Status = "Accepted for Publication", Title = "Optimal Flashy Transmission in Training-Based {MISO} {TDD} Systems", Year = "2011", };


	2010


	JOURNALS AND MAGAZINES:


	54)	R. Shams, P. Sadeghi, R. A. Kennedy and R. I. Hartley, "A survey of high performance medical image registration on multi-core, GPU and distributed architectures," IEEE Signal Process. Mag., pp. 50-60, 2010. PDF \| bibtex
		@article{shams:sadeghi:kennedy:hartley:spm:10, Author = "Shams, R. and Sadeghi, P. and Kennedy, R. A. and Hartley, R. I.", Date-Added = "2011-01-20 17:44:56 +1100", Date-Modified = "2011-01-21 15:03:27 +1100", Doi = "10.1109/MSP.2009.935387", Era-Rank = "B", Google-Scholar = "1", Journal = "IEEE Signal Process. Mag.", Link = "papers/2010/SPM_2010.pdf", Linkname = "PDF", Month = "March", Pages = "50-60", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2010/SPM_2010_GPU.pdf", Rating = "3", Status = "Published", Title = "A Survey of High Performance medical Image Registration on Multi-Core, {GPU} and Distributed Architectures", Year = "2010", Abstract = "In this article, we look at early, recent, and state-of-the-art methods for registration of medical images using a range of high-performance computing (HPC) architectures including symmetric multiprocessing (SMP), massively multiprocessing (MMP), and architectures with distributed memory (DM), and nonuniform memory access (NUMA). The article is designed to be self-sufficient. We will take the time to define and describe concepts of interest, albeit briefly, in the context of image registration and HPC. We provide an overview of the registration problem and its main components in the section Registration. Our main focus will be HPC-related aspects, and we will highlight relevant issues as we explore the problem domain. This approach presents a fresh angle on the subject than previously investigated by the more general and classic reviews in the literature [1]-[3]. The sections Multi-CPU Implementationsand Accelerator Implementations are organized from the perspective of high-performance and parallel- computing with the registration problem embodied. This is meant to equip the reader with the knowledge to map a registration problem to a given computing architecture.", };


	53)	R. Shams, P. Sadeghi, R. A. Kennedy and R. I. Hartley, "Parallel computation of mutual information on the GPU with application to real-time registration of 3D medical images," Computer Methods and Programs in Biomedicine, pp. 133-146, 2010. PDF \| bibtex
		@article{shams:sadeghi:kennedy:hartley:CMPB:10, Author = "Shams, R. and Sadeghi, P. and Kennedy, R. A. and Hartley, R. I.", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-20 18:04:10 +1100", Doi = "10.1016/j.cmpb.2009.11.004", Era-Rank = "A*", Google-Scholar = "3", Journal = "Computer Methods and Programs in Biomedicine", Link = "papers/2010/CMPB_2010.pdf", Linkname = "PDF", Month = "August", Number = "2", Pages = "133-146", Pdf-Url = "http://users.rsise.anu.edu.au/~rod/papers/2010/parcom.pdf", Rating = "5", Status = "Published", Title = "Parallel Computation of Mutual Information on the {GPU} with Application to Real-Time Registration of {3D} Medical Images", Volume = "99", Year = "2010", Abstract = "Due to processing constraints, automatic image-based registration of medical images has been largely used as a pre-operative tool. We propose a novel method named sort and count for efficient parallelization of mutual information (MI) computation designed for massively multi-processing architectures. Combined with a parallel transformation implementation and an improved optimization algorithm, our method achieves real-time (less than 1 s) rigid registration of 3D medical images using a commodity graphics processing unit (GPU). This represents a more than 50-fold improvement over a standard implementation on a CPU. Real-time registration opens new possibilities for development of improved and interactive intraoperative tools that can be used for enhanced visualization and navigation during an intervention.", };


	52)	R. Shams and P. Sadeghi, "On optimization of finite-difference time-domain (FDTD) computation on heterogeneous and GPU clusters," Journal of Parallel and Distributed Computing (accepted for publication), Sept. 2010. Preprint \| bibtex
		@article{shams:sadeghi:parallel:comp:11, Author = "Shams, R. and Sadeghi, P.", Date-Modified = "2011-01-21 11:21:03 +1100", Doi = "10.1016/j.jpdc.2010.10.011", Era-Rank = "A*", Google-Scholar = "0", Journal = "Journal of Parallel and Distributed Computing (accepted for publication)", Link = "papers/2011/JPDC_2011.pdf", Linkname = "Preprint", Month = sep, Rating = "5", Status = "Accepted for Publication", Title = "On optimization of finite-difference time-domain {(FDTD)} computation on heterogeneous and {GPU} clusters", Year = "2010", Abstract = "A model for the computational cost of the finite-difference time-domain (FDTD) method irrespective of implementation details or the application domain is given. The model is used to formalize the problem of optimal distribution of computational load to an arbitrary set of resources across a heterogeneous cluster. We show that the problem can be formulated as a minimax optimization problem and derive analytic lower bounds for the computational cost. The work provides insight into optimal design of FDTD parallel software. Our formulation of the load distribution problem takes simultaneously into account the computational and communication costs. We demonstrate that significant performance gains, as much as 75, can be achieved by proper load distribution.", };


	51)	P. Sadeghi, R. Shams and D. Traskov, "An optimal adaptive network coding scheme for minimizing decoding delay in broadcast erasure channels," EURASIP J. Wireless Commun. and Networking, June 2010. PDF \| bibtex
		@article{sadeghi:shams:traskov:eurasip:10, Author = "Sadeghi, P. and Shams, R. and Traskov, D.", Date-Modified = "2011-01-21 15:15:27 +1100", Doi = "10.1155/2010/618016", Era-Rank = "-", Google-Scholar = "0", Journal = "{EURASIP} J. Wireless Commun. and Networking", Link = "papers/2010/EURASIP_2010.pdf", Linkname = "PDF", Month = jun, Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2010/EURASIP_2010_NETCOD.pdf", Rating = "1", Status = "Published", Title = "An Optimal Adaptive Network Coding Scheme for Minimizing Decoding Delay in Broadcast Erasure Channels", Year = "2010", Abstract = "We are concerned with designing feedback-based adaptive network coding schemes with the aim of minimizing decoding delay in each transmission in packet-based erasure networks. We study systems where each packet brings new information to the destination regardless of its order and require the packets to be instantaneously decodable. We first formulate the decoding delay minimization problem as an integer linear program and then propose efficient algorithms for finding its optimal solution(s). We show that our problem formulation is applicable to memoryless erasures as well as Gilbert-Elliott erasures with memory. We then propose a number of heuristic algorithms with worst case linear execution complexity that can be used when an optimal solution cannot be found in a reasonable time. We verify the delay and speed performance of our techniques through numerical analysis. This analysis reveals that by taking channel memory into account in network coding decisions, one can considerably reduce decoding delays.", };


	50)	X. Zhou, T. A. Lamahewa, P. Sadeghi and S. Durrani, "Two-way training: optimal power allocation for pilot and data transmission," IEEE Trans. Wireless Commun., pp. 564-569, Feb. 2010. PDF \| bibtex
		@article{zhou:lamahewa:sadeghi:durrani:twc:10, Author = "Zhou, X. and Lamahewa, T. A. and Sadeghi, P. and Durrani, S.", Date-Modified = "2011-01-21 15:04:00 +1100", Doi = "10.1109/TWC.2010.02.090641", Era-Rank = "A", Google-Scholar = "2", Journal = "{IEEE} Trans. Wireless Commun.", Link = "papers/2010/TWC_2010.pdf", Linkname = "PDF", Month = feb, Number = "2", Pages = "564-569", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2010/TWC_2010_Two_way.pdf", Rating = "4", Status = "Published", Title = "Two-way training: optimal power allocation for pilot and data transmission", Volume = "9", Year = "2010", Abstract = "In this letter, we consider multiple-input single-output (MISO) systems with two-way training based transmission. We focus on the long-term system performance and study the optimal power allocation between reverse training, forward training and data transmission. We derive closed-form solutions for the optimal power allocation using high signal-to-noise ratio (SNR) approximations, and show that they achieve near optimal performance in terms of symbol error rate (SER) for different modulation schemes over a wide range of SNR values.", };


	CONFERENCES:


	49)	D. H. Chae, P. Sadeghi and R. A. Kennedy, "Robustness of compressive sensing under multiplicative perturbations: the challenge of fading channels," Proc. The 2010 Military Communications Conference, MILCOM 2010, San Jose, CA, 2010, pp. 296-301. PDF \| bibtex
		@inproceedings{chae:sadeghi:kennedy:milcom:10, Address = "San Jose, CA", Author = "Chae, D. H. and Sadeghi, P. and Kennedy, R. A.", Booktitle = "Proc. The 2010 Military Communications Conference, MILCOM 2010", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 11:20:16 +1100", Era-Rank = "-", Google-Scholar = "0", Link = "papers/2010/MILCOM_2010.pdf", Linkname = "PDF", Month = "October", Pages = "296-301", Pdf-Url = "http://users.rsise.anu.edu.au/~rod/papers/2010/p296-chae.pdf", Rating = "1", Status = "Published", Title = "Robustness of Compressive Sensing under Multiplicative Perturbations: The Challenge of Fading Channels", Year = "2010", Abstract = "We investigate the robustness of Compressive Sensing (CS) as a direct signal acquisition and reconstruction method at the wireless receiver in fading channels. The wireless channel introduces additive as well as multiplicative random perturbations to the received signal. The original CS theory considers only additive and bounded perturbation for signal reconstruction with an a priori known basis. However, the impact of multiplicative perturbations, which manifests itself as basis mismatch, on the CS reconstruction performance is largely unknown. In this paper we first formulate such multiplicative perturbations of wireless fading channel in the CS acquisition and reconstruction problem. We then show that these perturbations can result in significant errors in signal reconstruction if the basis is not properly adjusted. Furthermore, we will propose a method for adjusting the elements of basis to the fading channel coefficients and discuss possible improvements in the signal reconstruction.", };


	48)	D. H. Chae, P. Sadeghi and R. A. Kennedy, "Effects of basis-mismatch in compressive sampling of continuous sinusoidal signals," Proc. 2nd International Conference on Future Computer and Communication (ICFCC 2010), Wuhan, China, 2010, pp. 739-743. PDF \| bibtex
		@inproceedings{chae:sadeghi:kennedy:icfcc:10, Address = "Wuhan, China", Author = "Chae, D. H. and Sadeghi, P. and Kennedy, R. A.", Booktitle = "Proc. 2nd International Conference on Future Computer and Communication (ICFCC 2010)", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 11:21:55 +1100", Doi = "10.1109/ICFCC.2010.5497605", Era-Rank = "-", Google-Scholar = "1", Link = "papers/2010/ICFCC_2010.pdf", Linkname = "PDF", Month = "May", Pages = "739-743", Pdf-Url = "http://users.rsise.anu.edu.au/~rod/papers/2010/05497605.pdf", Rating = "1", Status = "Published", Title = "Effects of Basis-mismatch in Compressive Sampling of Continuous Sinusoidal Signals", Volume = "2", Year = "2010", Abstract = "The theory of compressive sampling (or compressed sensing) is very attractive in that it is possible to reconstruct some signals with a sub-Nyquist sampling rate provided that they are sparse in some basis domain. But if there exists a mismatch between the signal basis and the pre-defined reconstruction basis, the reconstruction performance is significantly degraded even if the signal is sparse enough. In this paper, the degradation due to this basis mismatch is investigated and a way to minimize the effects of basis mismatch in compressive sampling of continuous sinusoidal signals is discussed.", };


	47)	A. Sprintson, P. Sadeghi, G. Booker and S. El Rouayheb, "A randomized algorithm and performance bounds for coded cooperative data exchange," Proc. IEEE International Symp. Information Theory (ISIT), Ausin, TX, June 2010, pp. 1888-1892. PDF \| bibtex
		@inproceedings{sprintson:sadeghi:booker:elrouayheb:isit:10, Address = "Ausin, TX", Author = "Sprintson, A. and Sadeghi, P. and Booker, G. and El Rouayheb, S.", Booktitle = "Proc. {IEEE} International Symp. Information Theory {(ISIT)}", Date-Modified = "2011-01-21 12:09:41 +1100", Doi = "10.1109/ISIT.2010.5513313", Era-Rank = "B", Google-Scholar = "1", Link = "papers/2010/ISIT_2010.pdf", Linkname = "PDF", Month = jun, Pages = "1888-1892", Rating = "3", Status = "Published", Title = "A Randomized Algorithm and Performance Bounds for Coded Cooperative Data Exchange", Year = "2010", Abstract = "We consider scenarios where wireless clients are missing some packets, but they collectively know every packet. The clients collaborate to exchange missing packets over an error-free broadcast channel with capacity of one packet per channel use. First, we present an algorithm that allows each client to obtain missing packets, with minimum number of transmissions. The algorithm employs random linear coding over a sufficiently large field. Next, we show that the field size can be reduced while maintaining the same number of transmissions. Finally, we establish lower and upper bounds on the minimum number of transmissions that are easily computable and often tight as demonstrated by numerical simulations.", };


	46)	X. Zhou, P. Sadeghi and T. A. Lamahewa, "Optimizing training-based MIMO systems: how much time is needed for actual transmission?," Proc. IEEE Veh. Technol. Conf. (VTC), Taipei, Taiwan, May 2010, pp. 1-5. PDF \| bibtex
		@inproceedings{zhou:sadeghi:lamahewa:vtc:10, Address = "Taipei, Taiwan", Author = "Zhou, X. and Sadeghi, P. and Lamahewa, T. A.", Booktitle = "Proc. {IEEE} Veh. Technol. Conf. (VTC)", Date-Modified = "2011-01-21 12:09:43 +1100", Doi = "10.1109/VETECS.2010.5493832", Era-Rank = "B", Google-Scholar = "2", Link = "papers/2010/VTC_2010.pdf", Linkname = "PDF", Month = may, Pages = "1-5", Rating = "3", Status = "Published", Title = "Optimizing Training-based {MIMO} Systems: How Much Time is Needed for Actual Transmission?", Year = "2010", Abstract = "We study the design of training-based multiple-input multiple-output systems in two block-wise transmission schemes. The conventional transmission scheme has a fixed amount of energy to be used in each block, hence transmission takes place in every block. For this scheme, we study the optimality of using all available time in each block for transmission and provide bounds to significantly reduce the ranges of the possible values of the optimal training and data lengths. The second scheme, called the flashy transmission scheme, is constrained by an average amount of energy per block, and uses some but not necessarily all blocks for transmission. For this scheme, we find the optimal fraction of blocks to be used for transmission. When this optimal fraction is less than one, we show that the optimal training and data lengths are independent of the energy constraint.", };


	45)	C. Hucher and P. Sadeghi, "Hierarchical modulation-based cooperative scheme: minimizing the symbol error probability," Proc. International Conference on Telecommun. (ICT), Doha, Qatar, Apr. 2010, pp. 309-315. PDF \| bibtex
		@inproceedings{hucher:sadeghi:ict:10, Address = "Doha, Qatar", Author = "Hucher, C. and Sadeghi, P.", Booktitle = "Proc. International Conference on Telecommun. {(ICT)}", Date-Modified = "2011-01-21 15:08:59 +1100", Doi = "10.1109/ICTEL.2010.5478765", Era-Rank = "C", Google-Scholar = "0", Link = "papers/2010/ICT_2010.pdf", Linkname = "PDF", Month = apr, Pages = "309-315", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2010/IZS_2010.pdf", Rating = "2", Status = "Published", Title = "Hierarchical Modulation-based Cooperative Scheme: Minimizing the Symbol Error Probability", Year = "2010", Abstract = "In a cooperative network, relays are often closer to the source than the destination and thus the source-relay links have a higher capacity than the source-destination one. In this paper, we investigate a hierarchical modulation-based cooperative scheme, where the relay is able to detect the whole signal, while the destination can only detect the first layer of the modulation. We provide an error probability upper-bound for this scheme, which allows us to optimize the choice of the constellation parameter \theta.", };


	44)	C. Hucher and P. Sadeghi, "Mismatched decoding for the relay channel," Proc. International Zurich Seminar on Communications (IZS), Zurich, Switzerland, Mar. 2010, pp. 25-28. PDF \| bibtex
		@inproceedings{hucher:sadeghi:izs:10, Address = "Zurich, Switzerland", Author = "Hucher, C. and Sadeghi, P.", Booktitle = "Proc. International Zurich Seminar on Communications (IZS)", Date-Modified = "2011-01-21 15:23:18 +1100", Doi = "10.3929/ethz-a-005997152", Era-Rank = "-", Google-Scholar = "0", Link = "papers/2010/IZS_2010.pdf", Linkname = "PDF", Month = mar, Pages = "25-28", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2010/IZS_2010.pdf", Rating = "1", Status = "Published", Title = "Mismatched Decoding for the Relay Channel", Year = "2010", Abstract = "We consider a discrete memoryless relay channel, where both relay and destination may have an incorrect esti- mation of the channel. This estimation error is modeled with mismatched decoders. In this paper, we provide a lower-bound on the mismatch capacity of the relay channel. Moreover, we prove that this lower-bound is indeed the exact capacity for the degraded relay channel when random coding is used.", };


	43)	S. El Rouayheb, A. Sprintson and P. Sadeghi, "On coding for cooperative data exchange," Proc. IEEE Information Theory Workshop (ITW), Cairo, Egypt, Jan. 2010, pp. 118-122. PDF \| bibtex
		@inproceedings{elrouayheb:sprintson:sadeghi:itw:10, Address = "Cairo, Egypt", Author = "El Rouayheb, S. and Sprintson, A. and Sadeghi, P.", Booktitle = "Proc. {IEEE} Information Theory Workshop {(ITW)}", Date-Modified = "2011-01-21 15:09:36 +1100", Doi = "10.1109/ITWKSPS.2010.5503135", Era-Rank = "B", Google-Scholar = "5", Link = "papers/2010/ITW_2010.pdf", Linkname = "PDF", Month = jan, Pages = "118-122", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2010/ITW_2010.pdf", Rating = "3", Status = "Published", Title = "On Coding for Cooperative Data Exchange", Year = "2010", Abstract = "We consider the problem of data exchange by a group of closely-located wireless nodes. In this problem each node holds a set of packets and needs to obtain all the packets held by other nodes. Each of the nodes can broadcast the packets in its possession (or a combination thereof) via a noiseless broadcast channel of capacity one packet per channel use. The goal is to minimize the total number of transmissions needed to satisfy the demands of all the nodes, assuming that they can cooperate with each other and are fully aware of the packet sets available to other nodes. This problem arises in several practical settings, such as peer-to-peer systems and wireless data broadcast. In this paper, we establish upper and lower bounds on the optimal number of transmissions and present an efficient algorithm with provable performance guarantees. The effectiveness of our algorithms is established through numerical simulations.", };


	2009


	JOURNALS AND MAGAZINES:


	42)	T. A. Lamahewa, P. Sadeghi, R. A. Kennedy and P. B. Rapajic, "Model-based pilot and data power adaptation in PSAM with periodic delayed feedback," IEEE Trans. Wireless Commun., pp. 2247-2252, 2009. PDF \| bibtex
		@article{lamahewa:sadeghi:kennedy:rapajic:twc:09, Author = "Lamahewa, T. A. and Sadeghi, P. and Kennedy, R. A. and Rapajic, P. B.", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 15:10:22 +1100", Doi = "10.1109/TWC.2009.080526", Era-Rank = "A", Google-Scholar = "0", Journal = "IEEE Trans. Wireless Commun.", Link = "papers/2009/TWC_2009_Feedback.pdf", Linkname = "PDF", Month = "May", Number = "5", Pages = "2247-2252", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2009/TWC_2009_Feedback.pdf", Rating = "4", Status = "Published", Title = "Model-Based Pilot and Data Power Adaptation in {PSAM} with Periodic Delayed Feedback", Volume = "8", Year = "2009", Abstract = "We consider the optimum design of pilot-symbol-assisted modulation (PSAM) schemes with feedback. The received signal is periodically fed back to the transmitter through a noiseless delayed link and the time-varying channel is modeled as a Gauss-Markov process. We optimize a lower bound on the channel capacity which incorporates the PSAM parameters and Kalman-based channel estimation and prediction. The parameters available for the capacity optimization are the data power adaptation strategy, pilot spacing and pilot power ratio, subject to an average power constraint. Compared to the optimized feedback-less PSAM, our results show that even in the presence of feedback delay, the optimized power adaptation provides higher information rates at low signal-to-noise ratios (SNR) in medium-rate fading channels. In faster fading channels, suboptimal feedbackless equal power allocation to data and pilot is close to optimal at high SNR regime or when there is a delay in the feedback link.", };


	41)	X. Zhou, P. Sadeghi, T. A. Lamahewa and S. Durrani, "Design guidelines for training-based MIMO systems with feedback," IEEE Trans. Signal Processing, pp. 4014-4026, Oct. 2009. PDF \| bibtex
		@article{zhou:sadeghi:lamahewa:durrani:tsp:09, Author = "Zhou, X. and Sadeghi, P. and Lamahewa, T. A. and Durrani, S.", Date-Modified = "2011-01-21 15:22:14 +1100", Doi = "10.1109/TSP.2009.2023930", Era-Rank = "A*", Google-Scholar = "3", Journal = "{IEEE} Trans. Signal Processing", Link = "papers/2009/TSP_2009.pdf", Linkname = "PDF", Month = oct, Number = "10", Pages = "4014-4026", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2009/TSP_2009.pdf", Rating = "5", Status = "Published", Title = "Design guidelines for training-based {MIMO} systems with feedback", Volume = "57", Year = "2009", Abstract = "In this paper, we study the optimal training and data transmission strategies for block fading multiple-input multiple-output (MIMO) systems with feedback. We consider both the channel gain feedback (CGF) system and the channel covariance feedback (CCF) system. Using an accurate capacity lower bound as a figure of merit that takes channel estimation errors into account, we investigate the optimization problems on the temporal power allocation to training and data transmission as well as the training length. For CGF systems without feedback delay, we prove that the optimal solutions coincide with those for nonfeedback systems. Moreover, we show that these solutions stay nearly optimal even in the presence of feedback delay. This finding is important for practical MIMO training design. For CCF systems, the optimal training length can be less than the number of transmit antennas, which is verified through numerical analysis. Taking this fact into account, we propose a simple yet near optimal transmission strategy for CCF systems, and derive the optimal temporal power allocation over pilot and data transmission.", };


	40)	X. Zhou, P. Sadeghi, T. A. Lamahewa and S. Durrani, "Optimizing antenna configuration for MIMO systems with imperfect channel estimation," IEEE Trans. Wireless Commun., pp. 1177-1181, Mar. 2009. PDF \| bibtex
		@article{zhou:sadeghi:lamahewa:durrani:twc:09, Author = "Zhou, X. and Sadeghi, P. and Lamahewa, T. A. and Durrani, S.", Date-Modified = "2011-01-21 15:10:54 +1100", Doi = "10.1109/TWC.2009.080599", Era-Rank = "A", Google-Scholar = "1", Journal = "{IEEE} Trans. Wireless Commun.", Link = "papers/2009/TWC_2009_Antenna.pdf", Linkname = "PDF", Month = mar, Number = "3", Pages = "1177-1181", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2009/TWC_2009_Antenna.pdf", Rating = "4", Status = "Published", Title = "Optimizing Antenna Configuration for {MIMO} Systems with Imperfect Channel Estimation", Volume = "8", Year = "2009", Abstract = "We study the optimal antenna configuration (i.e. number of transmit and receive antennas) for multiple-input multiple-output systems in pilot-symbol-assisted modulation schemes with imperfect channel estimation. We assume block flat-fading channels and focus on a practical range of high signal-to-noise ratio. An ergodic capacity lower bound is used as the objective function to be maximized. We analytically study the capacity gain from adding extra antennas to the transmitter or to the receiver in two different scenarios. Our numerical results show that the optimal antenna configuration under imperfect channel estimation can be significantly different from that under perfect channel estimation assumption. In addition, we investigate the capacity gain from optimizing antenna configuration and find that the gain can be larger than that achieved by optimizing transmit power over pilot and data symbols, particularly for large block lengths.", };


	39)	P. Sadeghi, P. O. Vontobel and R. Shams, "Optimization of information rate upper and lower bounds for channels with memory," IEEE Trans. Inform. Theory, pp. 663-688, Feb. 2009. PDF \| bibtex
		@article{sadeghi:vontobel:shams:trans:it:09, Author = "Sadeghi, P. and Vontobel, P. O. and Shams, R.", Date-Modified = "2011-01-21 15:05:24 +1100", Doi = "10.1109/TIT.2008.2009581", Era-Rank = "A*", Google-Scholar = "3", Journal = "{IEEE} Trans. Inform. Theory", Link = "papers/2009/TIT_2009.pdf", Linkname = "PDF", Month = feb, Pages = "663-688", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2009/TIT_2009.pdf", Rating = "5", Selected = "2", Status = "Published", Title = "Optimization of Information Rate Upper and Lower Bounds for Channels with Memory", Year = "2009", Abstract = "We consider the problem of minimizing upper bounds and maximizing lower bounds on information rates of stationary and ergodic discrete-time channels with memory. The channels we consider can have a finite number of states, such as partial response channels, or they can have an infinite state space, such as time-varying fading channels. We optimize recently proposed information rate bounds for such channels, which make use of auxiliary finite-state machine channels (FSMCs). Our main contribution in this paper is to provide iterative expectation-maximization (EM) type algorithms to optimize the parameters of the auxiliary FSMC to tighten these bounds. We provide an explicit, iterative algorithm that improves the upper bound at each iteration. We also provide an effective method for iteratively optimizing the lower bound. To demonstrate the effectiveness of our algorithms, we provide several examples of partial response and fading channels where the proposed optimization techniques significantly tighten the initial upper and lower bounds. Finally, we compare our results with results obtained by the conjugate gradient optimization algorithm and an improved variation of the simplex algorithm, called Soblex. While the computational complexities of our algorithms are similar to the conjugate gradient method and less than the Soblex algorithm, our algorithms robustly find the tightest bounds. Interestingly, from a channel coding/decoding perspective, optimizing the lower bound is related to increasing the achievable mismatched information rate, i.e., the information rate of a communication system where the decoder at the receiver is matched to the auxiliary channel, and not to the original channel.", };


	CONFERENCES:


	38)	D. Traskov, M. Medard, P. Sadeghi and R. Koetter, "Joint scheduling and instantaneously decodable network coding," Proc. IEEE Global Commun. Conf. (Globecom), Honolulu, HI, Dec. 2009, pp. 1-6. PDF \| bibtex
		@inproceedings{traskov:medard:sadeghi:koetter:globecom:09, Address = "Honolulu, HI", Author = "Traskov, D. and Medard, M. and Sadeghi, P. and Koetter, R.", Booktitle = "Proc. {IEEE} Global Commun. Conf. {(Globecom)}", Date-Modified = "2011-01-21 15:12:11 +1100", Doi = "10.1109/GLOCOM.2009.5425315", Era-Rank = "B", Google-Scholar = "2", Link = "papers/2009/GLOBECOM_2009_DANAIL.pdf", Linkname = "PDF", Month = dec, Pages = "1-6", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2009/GLOBECOM_2009_2.pdf", Rating = "3", Status = "Published", Title = "Joint Scheduling and Instantaneously Decodable Network Coding", Year = "2009", Abstract = "We consider a wireless multi-hop network and design an algorithm for jointly optimal scheduling of packet transmissions and network coding. We consider network coding across different users, however with the restriction that packets have to be decoded after one hop. We compute the stability region of this scheme and propose an online algorithm that stabilizes every arrival rate vector within the stability region. The online algorithm requires computation of stable sets in an appropriately defined conflict graph. We show by means of simulations that this inherently hard problem is tractable for some instances and that network coding extends the stability region over routing and leads, on average, to a smaller backlog.", };


	37)	X. Zhou, T. A. Lamahewa, P. Sadeghi and S. Durrani, "Optimizing training-based transmission for correlated MIMO systems with hybrid feedback," Proc. IEEE Global Commun. Conf. (Globecom), Honolulu, HI, Dec. 2009, pp. 1-6. PDF \| bibtex
		@inproceedings{zhou:lamahewa:sadeghi:durrani:globecom:09, Address = "Honolulu, HI", Author = "Zhou, X. and Lamahewa, T. A. and Sadeghi, P. and Durrani, S.", Booktitle = "Proc. {IEEE} Global Commun. Conf. {(Globecom)}", Date-Modified = "2011-01-21 12:09:50 +1100", Doi = "10.1109/GLOCOM.2009.5425264", Era-Rank = "B", Google-Scholar = "0", Link = "papers/2009/GLOBECOM_2009_SEAN.pdf", Linkname = "PDF", Month = dec, Pages = "1-6", Rating = "3", Status = "Published", Title = "Optimizing Training-based Transmission for Correlated {MIMO} Systems with Hybrid Feedback", Year = "2009", Abstract = "In this paper, we consider multiple-input multiple-output (MIMO) communication systems with combined channel covariance feedback (CCF) and channel gain feedback (CGF), hereafter called hybrid CCF-CGF systems. Using an ergodic capacity lower bound as the figure of merit, we investigate the optimal training and data transmission strategies as well as the optimal transmit resource allocation. We prove that the optimal structure for data transmission follows a water-filling solution according to the estimated channel gains, rotated and truncated into the trained eigen-directions. We analytically find the range of the optimal training length. Through numerical evaluations we also show that a closed-form solution of the training power allocation achieves near optimal performance. Finally, we show that the capacity of hybrid CCF-CGF systems can be significantly increased by adding extra transmit antennas without increasing the training resources or feedback overhead.", };


	36)	X. Zhou, T. A. Lamahewa and P. Sadeghi, "Kalman filter-based channel estimation for amplify and forward relay communications," Proc. Asilomar Conference on Signals, Systems, and Computers, Pacific Grove, CA, Nov. 2009, pp. 1498-1502. PDF \| bibtex
		@inproceedings{zhou:lamahewa:sadeghi:asilomar:09, Address = "Pacific Grove, CA", Author = "Zhou, X. and Lamahewa, T. A. and Sadeghi, P.", Booktitle = "Proc. Asilomar Conference on Signals, Systems, and Computers", Date-Modified = "2011-01-21 12:09:59 +1100", Doi = "10.1109/ACSSC.2009.5470105", Era-Rank = "C", Google-Scholar = "0", Link = "papers/2009/ASILOMAR_2009.pdf", Linkname = "PDF", Month = nov, Pages = "1498-1502", Rating = "2", Status = "Published", Title = "Kalman Filter-based Channel Estimation for Amplify and Forward Relay Communications", Year = "2009", Abstract = "We propose an autoregressive model for the combined amplify and forward time-varying relay channel and derive a causal iterative channel estimation method using Kalman filter. This formulation enables us to study and compare two widely-used pilot transmission strategies in terms of the channel estimation errors. We provide a single-letter formula for the power allocation between the source and relay to achieve near optimal bit error rate (BER) performance in dual-hop communications. For cooperative communications, we show that the relay speed has a significant impact on the BER performance, and hence is important to be considered in practical system design.", };


	35)	F. Tabataba, P. Sadeghi and M. Pakravan, "A new power allocation scheme for amplify and forward incremental relaying," Proc. IEEE Int. Workshop on Signal Processing Advances for Wireless Communications (SPAWC), Perugia, Italy, June 2009, pp. 494-498. PDF \| bibtex
		@inproceedings{tabataba:sadeghi:pakravan:spawc:09, Address = "Perugia, Italy", Author = "Tabataba, F. and Sadeghi, P. and Pakravan, M.", Booktitle = "Proc. {IEEE} Int. Workshop on Signal Processing Advances for Wireless Communications {(SPAWC)}", Date-Modified = "2011-01-21 15:13:42 +1100", Doi = "10.1109/SPAWC.2009.5161834", Era-Rank = "-", Google-Scholar = "0", Link = "papers/2009/SPAWC_2009.pdf", Linkname = "PDF", Month = jun, Pages = "494-498", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2009/SPAWC_2009.pdf", Rating = "1", Status = "Published", Title = "A New Power Allocation Scheme For Amplify And Forward Incremental Relaying", Year = "2009", Abstract = "In this paper, we present a novel power allocation scheme for amplify and forward incremental relaying (IR) systems with the aim to minimize the overall outage probability at the destination. In our problem formulation, we take into account the outage-dependent activation of the relay when writing the power constraint. We provide a simple closed-form solution to the IR power allocation problem that is based on high signal-to-noise (SNR) approximation of the outage probability assuming maximum ratio combining (MRC) at the destination. We investigate the effectiveness of the proposed solution by comparing the achieved outage probabilities with those obtained through global numerical search. We find that the simple closed-form solution is almost optimal in many situations of interest and even at low SNR conditions. We observe that power-optimized IR needs significantly less power than power-optimized fixed relaying to achieve the same outage probability at the same effective rate. Finally, we show that our analytical power optimization for IR-MRC systems is also applicable to IR systems with selection diversity and results in almost optimal outage probability.", };


	34)	P. Sadeghi, D. Traskov and R. Koetter, "Adaptive network coding for broadcast channels," Proc. 2009 Workshop on Network Coding, Theory, and Applications (NetCod), Lausanne, Switzerland, June 2009, pp. 80-85. PDF \| bibtex
		@inproceedings{sadeghi:traskov:koetter:netcod:09, Address = "Lausanne, Switzerland", Author = "Sadeghi, P. and Traskov, D. and Koetter, R.", Booktitle = "Proc. 2009 Workshop on Network Coding, Theory, and Applications {(NetCod)}", Date-Modified = "2011-01-21 15:14:25 +1100", Doi = "10.1109/NETCOD.2009.5191398", Era-Rank = "-", Google-Scholar = "8", Link = "papers/2009/NETCOD_2009.pdf", Linkname = "PDF", Month = jun, Pages = "80-85", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2009/NETCOD_2009.pdf", Rating = "1", Status = "Published", Title = "Adaptive network coding for broadcast channels", Year = "2009", Abstract = "We consider the throughput-delay tradeoff in network coded transmission over erasure broadcast channels. Interested in minimizing decoding delay, we formulate the problem of instantly decodable network coding as an integer linear program and propose algorithms to solve it heuristically. In particular, we investigate channels with memory and propose algorithms that can exploit channel erasure dependence to increase throughput and decrease delay.", };


	33)	J. K. Sundararajan, P. Sadeghi and M. Medard, "A feedback-based adaptive broadcast coding scheme for reducing in-order delivery delay," Proc. 2009 Workshop on Network Coding, Theory, and Applications (NetCod), Lausanne, Switzerland, June 2009, pp. 1-6. PDF \| bibtex
		@inproceedings{sundararajan:sadeghi:medard:netcod:09, Address = "Lausanne, Switzerland", Author = "Sundararajan, J. K. and Sadeghi, P. and Medard, M.", Booktitle = "Proc. 2009 Workshop on Network Coding, Theory, and Applications {(NetCod)}", Date-Modified = "2011-01-21 15:16:00 +1100", Doi = "10.1109/NETCOD.2009.5437470", Era-Rank = "-", Google-Scholar = "3", Link = "papers/2009/NETCOD_2009_2.pdf", Linkname = "PDF", Month = jun, Pages = "1-6", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2009/NETCOD_2009_2.pdf", Rating = "1", Status = "Published", Title = "A Feedback-based Adaptive Broadcast Coding Scheme for Reducing In-order Delivery Delay", Year = "2009", Abstract = "We propose a new feedback-based adaptive coding scheme for a packet erasure broadcast channel. The main performance metric of interest is the delay. We consider two types of delay - decoding delay and delivery delay. Decoding delay is the time difference between the instant when the packet is decoded at an arbitrary receiver and the instant when it arrived at the sender. Delivery delay also includes the period when a decoded packet waits in a resequencing buffer at the receiver until all previous packets have also been decoded. This notion of delay is motivated by applications that accept packets only in order. Our coding scheme has the innovation guarantee property and is hence throughput optimal. It also allows efficient queue management. It uses the simple strategy of mixing only the oldest undecoded packet of each receiver, and therefore extends to any number of receivers. We conjecture that this scheme achieves the asymptotically optimal delivery (and hence decoding) delay. The asymptotic behavior is studied in the limit as the load factor of the system approaches capacity. This conjecture is verified through simulations.", };


	32)	R. Iqbal, T. Abhayapala and P. Sadeghi, "A technique to improve MMSE performance of PACE in time-selective Rayleigh fading channels," Proc. 2009 Canadian Workshop On Information Theory CWIT, Ottawa, Canada, May 2009, pp. 157-160. PDF \| bibtex
		@inproceedings{iqbal:abhayapala:sadeghi:cwit:09, Address = "Ottawa, Canada", Author = "R. Iqbal and T. Abhayapala and P. Sadeghi", Booktitle = "Proc. 2009 Canadian Workshop On Information Theory {CWIT}", Date-Modified = "2011-01-21 15:17:06 +1100", Doi = "10.1109/WCNC.2009.4917724", Era-Rank = "-", Link = "papers/2009/CWIT_2009.pdf", Linkname = "PDF", Month = may, Pages = "157-160", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2009/CWIT_2009.pdf", Rating = "1", Year = "2009", Status = "Published", Title = "A Technique to Improve {MMSE} Performance of {PACE} in Time-Selective {Rayleigh} Fading Channels", Abstract = "The so-called peaky signaling has been shown to improve the performance of a communication system over noncoherent fading channels in the low signal-to-noise ratio (SNR) regime. We consider a signaling scheme which is equivalent to peaky signaling over a time-selective Rayleigh fading channel and make use of the unused degrees of freedom to improve the minimum mean square error (MMSE) performance of pilot-aided channel estimation (PACE) by a processing technique incorporating low pass filtering and downsampling. We assume infinite pilot symbols and optimal Wiener smoother at the receiver and give some analytical as well numerical results suggesting significant gains in MMSE performance of PACE.", };


	31)	S. Taylor and P. Sadeghi, "Finite-state Markov modelling of frequency-selective fading channels with correlated taps," Proc. IEEE Wireless Communications and Networking Conference (WCNC), Budapest, Hungary, Apr. 2009, pp. 1-6. PDF \| bibtex
		@inproceedings{taylor:sadeghi:wcnc:09, Address = "Budapest, Hungary", Author = "Taylor, S. and Sadeghi, P.", Booktitle = "Proc. {IEEE} Wireless Communications and Networking Conference {(WCNC)}", Date-Modified = "2011-01-21 15:17:06 +1100", Doi = "10.1109/WCNC.2009.4917724", Era-Rank = "-", Google-Scholar = "0", Link = "papers/2009/WCNC_2009.pdf", Linkname = "PDF", Month = apr, Pages = "1-6", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2009/WCNC_2009.pdf", Rating = "1", Status = "Published", Title = "Finite-State {Markov} Modelling of Frequency-Selective Fading Channels with Correlated Taps", Year = "2009", Abstract = "We consider the problem of modelling a randomly time-varying frequency-selective fading channel as a finite-state Markov channel (FSMC). For a fading channel with two correlated taps and given statistical parameters, the accuracy of an FSMC is assessed by comparing its information rate, when the receiver has ideal channel-state information, to that of the original continuous-valued channel. We show that in order to construct an FSMC with a given desired accuracy, fewer states are required if the correlation between taps is taken into account than if the taps are treated as being independent. These results demonstrate the suitability and accuracy of FSMCs for modelling a time-varying frequency-selective fading channel with memory.", };


	30)	R. Iqbal, P. Sadeghi and T. Abhayapala, "Constant power signaling in Rayleigh fading channels: joint output probability distribution and information rate bounds," Proc. 2009 World Congress on Computer Science and Information Engineering (CSIE), Los Angeles, CA, Mar. 2009, pp. 166-170. PDF \| bibtex
		@inproceedings{iqbal:sadeghi:abhayapala:csie:09, Address = "Los Angeles, CA", Author = "Iqbal, R. and Sadeghi, P. and Abhayapala, T.", Booktitle = "Proc. 2009 World Congress on Computer Science and Information Engineering {(CSIE)}", Date-Modified = "2011-01-21 15:19:29 +1100", Doi = "10.1109/CSIE.2009.482", Era-Rank = "-", Google-Scholar = "0", Link = "papers/2009/CSIE_2009.pdf", Linkname = "PDF", Month = mar, Pages = "166-170", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2009/CSIE_2009.pdf", Rating = "1", Status = "Published", Title = "Constant Power Signaling in {Rayleigh} Fading Channels: Joint Output Probability Distribution and Information Rate Bounds", Year = "2009", Abstract = "In this paper, we consider a wireless communication scenario in which the channel output is marginally Gaussian, but not jointly Gaussian. In particular, we study the joint probability distribution of channel outputs in correlated Rayleigh fading channels in response to constant power signaling, such as M-ary phase shift keying (MPSK). We show that the distribution of the channel output at any given sampling time is marginally Gaussian. However, the joint distribution of a sequence of channel outputs cannot be jointly Gaussian. A consequence of this result is that the information rates stated to be exact in two recent contributions, are strict upper bounds to the achievable data rates. We examine the tightness of these upper bounds by comparing them with the MPSK upper bound under perfect channel state information (CSI) assumption. We find that the CSI upper bound is considerably tighter in slow fading channels, high signal-to-noise ratios, and low-dimension (such as binary) PSK signaling.", };


	29)	F. Tabataba, P. Sadeghi, T. A. Lamahewa and M. Pakravan, "Statistical properties of amplify and forward relay links with channel estimation errors," Proc. 2009 Australian Commun. Theory Workshop (AusCTW), Sydney, Australia, Feb. 2009, pp. 44-49. PDF \| bibtex
		@inproceedings{tabataba:sadeghi:lamahewa:pakravan:ausctw:09, Address = "Sydney, Australia", Author = "Tabataba, F. and Sadeghi, P. and Lamahewa, T. A. and Pakravan, M.", Booktitle = "Proc. 2009 Australian Commun. Theory Workshop {(AusCTW)}", Date-Modified = "2011-01-21 15:19:50 +1100", Doi = "10.1109/AUSCTW.2009.4805598", Era-Rank = "-", Google-Scholar = "2", Link = "papers/2009/AUSCTW_2009.pdf", Linkname = "PDF", Month = feb, Pages = "44-49", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2009/AUSCTW_2009.pdf", Rating = "1", Status = "Published", Title = "Statistical Properties of Amplify and Forward Relay Links with Channel Estimation Errors", Year = "2009", Abstract = "This paper studies the statistical properties of the signal-to-noise ratio (SNR) of the relay link in a cooperative wireless communication system with fixed gain relay in presence of channel estimation error. The SNR expression is derived and three different analytic approaches with different approximate assumptions are used to obtain the probability distribution function of the SNR and outage probability of the relay link. The first approach is the most accurate one in many cases, however it does not have a closed-form expression. The other two approaches result in closed-form expressions for the outage probability. Therefore, the third approach has been used to find a sub-optimum power allocation scheme for the source and the relay. The numerical results compare the accuracy of the analytic approaches and simulation results for different positions of the relay between the source and the destination. It is shown that the second approach has the most accurate closed-form expression and the third one leads to the simplest closed-form result suitable for power optimization purposes.", };


	2008


	JOURNALS AND MAGAZINES:


	28)	P. Sadeghi, R. A. Kennedy, P. B. Rapajic and R. Shams, "Finite-state markov modeling of fading channels: a survey of principles and applications," IEEE Signal Process. Mag., pp. 57-80, 2008. PDF \| bibtex
		@article{sadeghi:kennedy:rapajic:shams:sp:mag:08, Author = "Sadeghi, P. and Kennedy, R. A. and Rapajic, P. B. and Shams, R.", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 15:04:52 +1100", Doi = "10.1109/MSP.2008.926683", Era-Rank = "B", Google-Scholar = "34", Journal = "IEEE Signal Process. Mag.", Link = "papers/2008/SPM_2008.pdf", Linkname = "PDF", Month = "September", Number = "5", Pages = "57-80", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2008/SPM_2008.pdf", Rating = "3", Status = "Published", Title = "Finite-State Markov Modeling of Fading Channels: A Survey of Principles and Applications", Volume = "25", Year = "2008", Abstract = "Wireless communication systems that operate through fading channels have become more diverse and complex. In the last ten years, there has been a growing interest for research and development of advanced wireless communications systems that employ multicarrier (MC) techniques. So far, applications of FSMC models for fading channels has been mainly limited to single carrier (SC) communications with very few exceptions [24], [47]. FSMC models are particulary suitable to represent and estimate the relatively fast flat-fading channel gain in each subcarrier. An unexplored avenue for research is to find appropriate FSMC models to represent MC fading channels. However, the number of TV-FFC gains to be modeled in the MC system is often much higher than in a SC system and a major challenge would be to keep the number of FSMC states to computationally manageable levels.", };


	27)	P. Sadeghi and P. Rapajic, "On information rates of time-varying fading channels modeled as finite-state Markov channels," IEEE Trans. Commun., pp. 1268-1278, Aug. 2008. PDF \| bibtex
		@article{sadeghi:rapajic:trans:com:08, Author = "Sadeghi, P. and Rapajic, P.", Date-Modified = "2011-01-21 15:07:43 +1100", Doi = "10.1109/TCOMM.2008.060622", Era-Rank = "A*", Google-Scholar = "4", Journal = "{IEEE} Trans. Commun.", Link = "papers/2008/TCOM_2008.pdf", Linkname = "PDF", Month = aug, Number = "8", Pages = "1268-1278", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2008/TCOM_2008.pdf", Rating = "5", Selected = "4", Status = "Published", Title = "On information rates of time-varying fading channels modeled as finite-state {Markov} channels", Volume = "56", Year = "2008", Abstract = "We study information rates of time-varying flat-fading channels (FFC) modeled as finite-state Markov channels (FSMC). FSMCs have two main applications for FFCs: modeling channel error bursts and decoding at the receiver. Our main finding in the first application is that receiver observation noise can more adversely affect higher-order FSMCs than lower-order FSMCs, resulting in lower capacities. This is despite the fact that the underlying higher-order FFC and its corresponding FSMC are more predictable. Numerical analysis shows that at low to medium SNR conditions (SNR lsim 12 dB) and at medium to fast normalized fading rates (0.01 lsim fDT lsim 0.10), FSMC information rates are non-increasing functions of memory order. We conclude that BERs obtained by low-order FSMC modeling can provide optimistic results. To explain the capacity behavior, we present a methodology that enables analytical comparison of FSMC capacities with different memory orders. We establish sufficient conditions that predict higher/lower capacity of a reduced-order FSMC, compared to its original high-order FSMC counterpart. Finally, we investigate the achievable information rates in FSMC-based receivers for FFCs. We observe that high-order FSMC modeling at the receiver side results in a negligible information rate increase for normalized fading rates fDT lsim 0.01.", };


	CONFERENCES:


	26)	X. Zhou, T. A. Lamahewa, P. Sadeghi and S. Durrani, "Capacity of MIMO systems: impact of spatial correlation with channel estimation errors?," Proc. IEEE Int. Conf. on Commun. Systems (ICCS), Guangzhou, China, Nov. 2008, pp. 817-822. PDF \| bibtex
		@inproceedings{zhou:lamahewa:sadeghi:durrani:iccs:08, Address = "Guangzhou, China", Author = "Zhou, X. and Lamahewa, T. A. and Sadeghi, P. and Durrani, S.", Booktitle = "Proc. {IEEE} Int. Conf. on Commun. Systems {(ICCS)}", Date-Modified = "2011-01-21 15:20:18 +1100", Doi = "10.1109/ICCS.2008.4737299", Era-Rank = "-", Google-Scholar = "1", Link = "papers/2008/ICCS_2008.pdf", Linkname = "PDF", Month = nov, Pages = "817-822", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2008/ICCS_2008.pdf", Rating = "1", Status = "Published", Title = "Capacity of {MIMO} Systems: Impact of Spatial Correlation with Channel Estimation Errors?", Year = "2008", Abstract = "We study the impact of channel spatial correlation on the ergodic capacity of multiple-input multiple-output (MIMO) systems with channel estimation errors in block-fading channels. We consider transmit antenna correlation and use an accurate capacity lower bound to carry out the theoretical analysis for MIMO systems with and without covariance feedback. We show that for non-feedback systems, the capacity increases with channel correlation at low signal-to-noise ratio (SNR). This finding is in contrast to the existing result for non-feedback systems with perfect channel estimation. For covariance feedback systems, we find that the capacity increases with correlation. We also show the robustness of equal power transmission and the optimality of beamforming at low SNR for non-feedback and covariance feedback systems, respectively. Our numerical results validate our analysis and show that the theoretical low SNR analysis can extend to moderate SNR values.", };


	25)	X. Zhou, T. A. Lamahewa, P. Sadeghi and S. Durrani, "Designing PSAM schemes: how optimal are SISO pilot parameters for spatially correlated SIMO?," Proc. IEEE Int. Symp. on Personal, Indoor and Mobile Radio Commun. (PIMRC), Cannes, France, Sept. 2008, pp. 1-6. PDF \| bibtex
		@inproceedings{zhou:lamahewa:sadeghi:durrani:pimrc:08, Address = "Cannes, France", Author = "Zhou, X. and Lamahewa, T. A. and Sadeghi, P. and Durrani, S.", Booktitle = "Proc. {IEEE} Int. Symp. on Personal, Indoor and Mobile Radio Commun. {(PIMRC)}", Date-Modified = "2011-01-21 15:20:40 +1100", Doi = "10.1109/PIMRC.2008.4699449", Era-Rank = "-", Google-Scholar = "2", Link = "papers/2008/PIMRC_2008.pdf", Linkname = "PDF", Month = sep, Pages = "1-6", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2008/PIMRC_2008.pdf", Rating = "1", Status = "Published", Title = "Designing {PSAM} Schemes: How Optimal are {SISO} Pilot Parameters for Spatially Correlated {SIMO}?", Year = "2008", Abstract = "We study the design parameters of pilot-symbol-assisted modulation (PSAM) schemes for spatially correlated single-input multiple-output (SIMO) systems in time-varying Gauss-Markov flat-fading channels. We use an information capacity lower bound as our figure of merit. We investigate the optimum design parameters, including the ratio of power allocated to the pilots and the fraction of time occupied by the pilots, for SIMO systems with different antenna sizes and with spatial channel correlation. Our main finding is that by optimally designing the training parameters for single-input single-output (SISO) systems, the same parameters can be used to achieve near optimum capacity in both spatially independent and correlated SIMO systems for the same fading rate and signal-to-noise ratio (SNR). In addition, we show that spatially independent channels give the lowest capacity at sufficiently low SNR. These findings provide insights into the design of practical PSAM systems.", };


	2007


	JOURNALS AND MAGAZINES:


	24)	R. A. Kennedy, P. Sadeghi, T. D. Abhayapala and H. M. Jones, "Intrinsic limits of dimensionality and richness in random multipath fields," IEEE Trans. Signal Processing, pp. 2542-2556, 2007. PDF \| bibtex
		@article{kennedy:sadeghi:abhayapala:jones:trans:sp:07, Author = "Kennedy, R. A. and Sadeghi, P. and Abhayapala, T. D. and Jones, H. M.", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 16:53:10 +1100", Doi = "10.1109/TSP.2007.893738", Era-Rank = "A*", Google-Scholar = "32", Gsdoi = "0", Journal = "IEEE Trans. Signal Processing", Link = "papers/2007/TSP_2007.pdf", Linkname = "PDF", Month = "June", Number = "6", Pages = "2542-2556", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2007/TSP_2007.pdf", Rating = "5", Status = "Published", Title = "Intrinsic limits of dimensionality and richness in random multipath fields", Volume = "55", Year = "2007", Abstract = "We study the dimensions or degrees of freedom of farfield multipath that is observed in a limited, source-free region of space. The multipath fields are studied as solutions to the wave equation in an infinite-dimensional vector space. We prove two universal upper bounds on the truncation error of fixed and random multipath fields. A direct consequence of the derived bounds is that both fixed and random multipath fields have an effective finite dimension. This finite dimension is linearly proportional to the radius of the two-dimensional spatial region where the field is coupled to. We use the Karhunen-Loeve (KL) expansion of random multipath fields to quantify the notion of multipath richness. The multipath richness is defined as the number of significant eigenvalues in the KL expansion that achieves 99 of the total multipath energy. We prove a lower bound on the largest multipath eigenvalue and use this bound to show that reducing the angular range of multipath power spectrum reduces multipath richness. We also provide a systematic numerical algorithm to find multipath eigenvalues, which unlike the Fredholm equation, does not require selecting quadrature points.", };


	CONFERENCES:


	23)	R. Shams, R. A. Kennedy and P. Sadeghi, "Efficient image registration by decoupled parameter estimation using gradient-based techniques and mutual information," Proc. TENCON 2007, Taipei, Taiwan, 2007, pp. 1-4. PDF \| bibtex
		@inproceedings{shams:kennedy:sadeghi:tencon:2007, Address = "Taipei, Taiwan", Author = "Shams, R. and Kennedy, R. A. and Sadeghi, P.", Booktitle = "Proc. TENCON 2007", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 12:09:56 +1100", Doi = "10.1109/TENCON.2007.4428829", Era-Rank = "C", Google-Scholar = "2", Gsdoi = "No", Link = "papers/2007/TENCON_2007.pdf", Linkname = "PDF", Month = "October-November", Pages = "1-4", Pdf-Url = "http://users.rsise.anu.edu.au/~rod/papers/2007/04428829.pdf", Rating = "2", Status = "Published", Title = "Efficient Image Registration by Decoupled Parameter Estimation Using Gradient-Based Techniques and Mutual Information", Year = "2007", Abstract = "We present an efficient and accurate method for similarity (rigid+scale) registration of 3D images by decoupled estimation of transformation parameters. The estimated parameters are used to initialize the search for a more accurate alignment by optimizing a mutual information-based cost function. We use computationally inexpensive methods based on image gradients to obtain the original estimates. Our method improves the efficiency of the overall registration task by allowing the more expensive optimization step to converge quickly. It also makes the registration more robust and less sensitive to the shape of the cost function by reducing the chance of the optimization algorithm being caught by a local minimum. Our experiments demonstrate up to 10-fold increase in computational efficiency and significant reduction in misalignment.", };


	22)	R. Shams, R. A. Kennedy, P. Sadeghi and R. I. Hartley, "Gradient intensity-based registration of multi-modal images of the brain," Proc. Eleventh IEEE International Conference on Computer Vision, ICCV 2007, Rio de Janeiro, Brazil, 2007, pp. 1-8. PDF \| bibtex
		@inproceedings{shams:kennedy:sadeghi:hartley:iccv:07, Address = "Rio de Janeiro, Brazil", Author = "Shams, R. and Kennedy, R. A. and Sadeghi, P. and Hartley, R. I.", Booktitle = "Proc. Eleventh IEEE International Conference on Computer Vision, ICCV 2007", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 11:23:38 +1100", Doi = "10.1109/ICCV.2007.4409080", Era-Rank = "A", Google-Scholar = "12", Link = "papers/2007/ICCV_2007.pdf", Linkname = "PDF", Month = "October", Pages = "1-8", Pdf-Url = "http://users.rsise.anu.edu.au/~rod/papers/2007/04409080.pdf", Rating = "4", Status = "Published", Title = "Gradient Intensity-Based Registration of Multi-Modal Images of the Brain", Year = "2007", Abstract = "We present a fast and accurate framework for registration of multi-modal volumetric images based on decoupled estimation of registration parameters utilizing spatial information in the form of `gradient intensity'. We introduce gradient intensity as a measure of spatial strength of an image in a given direction and show that it can be used to determine the rotational misalignment independent of translation between the images. The rotation parameters are obtained by maximizing the mutual information of 2D gradient intensity matrices obtained from 3D images, hence reducing the dimensionality of the problem and improving efficiency. The rotation parameters along with estimations of translation are then used to initialize an optimization step over a conventional pixel intensity-based method to achieve sub-voxel accuracy. Our optimization algorithm converges quickly and is less subject to the common problem of mis-registration due to local extrema. Experiments show that our method significantly improves the robustness, performance and efficiency of registration compared to conventional pixel intensity-based methods.", };


	21)	R. Shams, P. Sadeghi and R. A. Kennedy, "Gradient intensity: A new mutual information based registration method," Proc. IEEE Conference on Computer Vision and Pattern Recognition, CVPR '07, Minneapolis, Minnesota, 2007, pp. 1-8. PDF \| bibtex
		@inproceedings{shams:sadeghi:kennedy:cvpr:07, Address = "Minneapolis, Minnesota", Author = "Shams, R. and Sadeghi, P. and Kennedy, R. A.", Booktitle = "Proc. IEEE Conference on Computer Vision and Pattern Recognition, CVPR '07", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 11:23:39 +1100", Doi = "10.1109/CVPR.2007.383425", Era-Rank = "A", Google-Scholar = "9", Link = "papers/2007/CVPR_2007.pdf", Linkname = "PDF", Month = "June", Pages = "1-8", Pdf-Url = "http://users.rsise.anu.edu.au/~rod/papers/2007/04270423.pdf", Rating = "4", Status = "Published", Title = "Gradient intensity: {A} new mutual information based registration method", Year = "2007", Abstract = "Conventional mutual information (MI)-based registration using pixel intensities is time-consuming and ignores spatial information, which can lead to misalignment. We propose a method to overcome these limitation by acquiring initial estimates of transformation parameters. We introduce the concept of `gradient intensity' as a measure of spatial strength of an image in a given direction. We determine the rotation parameter by maximizing the MI between gradient intensity histograms. Calculation of the gradient intensity MI function is extremely efficient. Our method is designed to be invariant to scale and translation between the images. We then obtain estimates of scale and translations parameters using methods based on the centroids of gradient images. The estimated parameters are used to initialize an optimization algorithm which is designed to converge more quickly than the standard Powell algorithm in close proximity of the minimum. Experiments show that our method significantly improves the performance of the registration task and reduces the overall computational complexity by an order of magnitude.", };


	20)	P. Sadeghi, Y. Liu, R. A. Kennedy and P. B. Rapajic, "Pilot symbol transmission for time-varying fading channels: an information-theoretic optimization," Proc. International Conference on Signal Processing and Communication Systems, ICSPCS'2007, Gold Coast, Australia, 2007, pp. 34-40. PDF \| bibtex
		@inproceedings{sadeghi:liu:kennedy:rapajic:icspcs:07, Address = "Gold Coast, Australia", Author = "Sadeghi, P. and Liu, Y. and Kennedy, R. A. and Rapajic, P. B.", Booktitle = "Proc. International Conference on Signal Processing and Communication Systems, ICSPCS'2007", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 15:21:06 +1100", Era-Rank = "-", Google-Scholar = "4", Link = "papers/2007/ICSPCS_2007.pdf", Linkname = "PDF", Month = "December", Pages = "34-40", Pdf-Url = "http://users.rsise.anu.edu.au/~rod/papers/2007/ICSPCS07_34-40.pdf", Rating = "1", Status = "Published", Title = "Pilot Symbol Transmission for Time-Varying Fading Channels: An Information-Theoretic Optimization", Year = "2007", Abstract = "We consider the optimal design of pilot-symbol-ulation (PSAM) in time-varying flat-fading channels (FFC). The FFC is modeled as an autoregressive Gauss-Markov random process, whose realization is unknown at the transmitter or at the receiver. Our measure of optimality for channel estimation is the rate of information transfer through the channel. The parameters that are available for this optimization are the power ratio and the fraction of time that are allocated to pilot transmission. Our approach is different from (and builds upon) a recent study of PSAM for the Gauss-Markov FFC, where the aim was to minimize the maximum steady-state minimum mean square error (MMSE) of channel estimation for equal power allocated to pilot and data symbols and for a fixed pilot insertion ratio. To this end, we examine a lower bound on the capacity and find the optimal pilot transmission parameters that maximize this bound. Our analysis shows that this capacity lower bound is more sensitive to the pilot power allocation ratio in relatively slow fading channels (with the normalized fading rate fD Ts 0.01). We observe that for such slow fading rates, optimal power allocation and optimal pilot spacing are more sensitive to the operating SNR. Another finding is that equal power allocation strategy is suboptimal by at most 1 dB for the slow fading rate of fD Ts = 0.01.", };


	19)	S. Taylor and P. Sadeghi, "Capacity analysis of time-varying flat-fading channels using particle methods," Proc. Australian Telecommunication Networks and Applications Conference (ATNAC), Christchurch, New Zealand, Dec. 2007, pp. 425-430. PDF \| bibtex
		@inproceedings{taylor:sadeghi:atnac:07, Address = "Christchurch, New Zealand", Author = "Taylor, S. and Sadeghi, P.", Booktitle = "Proc. Australian Telecommunication Networks and Applications Conference (ATNAC)", Date-Modified = "2011-01-21 15:17:17 +1100", Doi = "10.1109/ATNAC.2007.4665274", Era-Rank = "-", Google-Scholar = "0", Link = "papers/2007/ATNAC_2007.pdf", Linkname = "PDF", Month = dec, Pages = "425-430", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2007/ATNAC_2007.pdf", Rating = "1", Status = "Published", Title = "Capacity Analysis of Time-Varying Flat-Fading Channels Using Particle Methods", Year = "2007", };


	18)	P. Sadeghi, P. O. Vontobel and R. Shams, "Optimizing information rate bounds for channels with memory," Proc. IEEE Int. Symp. on Inform. Theory (ISIT), Nice, France, June 2007, pp. 171-175. PDF \| bibtex
		@inproceedings{sadeghi:vontobel:shams:isit:07, Address = "Nice, France", Author = "Sadeghi, P. and Vontobel, P. O. and Shams, R.", Booktitle = "Proc. {IEEE} Int. Symp. on Inform. Theory ({ISIT})", Date-Modified = "2011-01-21 15:18:32 +1100", Doi = "10.1109/ISIT.2007.4557222", Era-Rank = "B", Google-Scholar = "5", Link = "papers/2007/ISIT_2007.pdf", Linkname = "PDF", Month = jun, Pages = "171-175", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2007/ISIT_2007.pdf", Rating = "3", Status = "Published", Title = "Optimizing information rate bounds for channels with memory", Year = "2007", Abstract = "We consider the problem of optimizing information rate upper and lower bounds for communication channels with (possibly large) memory. A recently proposed auxiliary-channel-based technique allows one to efficiently compute upper and lower bounds on the information rate of such channels. Towards tightening these bounds, we propose iterative expectation-maximization (EM) type algorithms to optimize the parameters of the auxiliary finite-state machine channel (FSMC). From a channel coding perspective, optimizing the lower bound is related to increasing the achievable mismatched information rate, i.e. the information rate of a communication system where the maximum-likelihood decoder at the receiver is matched to the auxiliary channel and not to the true channel. We provide explicit solutions for optimizing the upper bound and the difference between the upper and the lower bound and we discuss a method for the optimization of the lower bound for data-controllable channels with memory. We discuss examples of channels with memory, for which application of the developed theory results in noticeably tighter information rate bounds.", };


	17)	R. Shams and P. Sadeghi, "Bar code recognition in highly distorted and low resolution images," Proc. IEEE Int. Conf. on Acoustics, Speech, and Signal Processing (ICASSP), Honolulu, HI, Apr. 2007, pp. I-737-I-740. PDF \| bibtex
		@inproceedings{shams:sadeghi:icassp:07, Address = "Honolulu, HI", Author = "Shams, R. and Sadeghi, P.", Booktitle = "Proc. {IEEE} Int. Conf. on Acoustics, Speech, and Signal Processing ({ICASSP})", Date-Modified = "2011-01-21 15:21:35 +1100", Doi = "10.1109/ICASSP.2007.366013", Era-Rank = "B", Google-Scholar = "6", Link = "papers/2007/ICASSP_2007.pdf", Linkname = "PDF", Month = apr, Pages = "I-737-I-740", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2007/ICASSP_2007.pdf", Rating = "3", Status = "Published", Title = "Bar Code Recognition in Highly Distorted and Low Resolution Images", Volume = "1", Year = "2007", Abstract = "In this paper, we present a novel approach to detection of one dimensional bar code images. Our algorithm is particularly designed to recognize bar codes, where the image may be of low resolution, low quality or suffer from substantial blurring, de-focusing, non-uniform illumination, noise and color saturation. The algorithm is accurate, fast, scalable and can be easily adjusted to search for a valid result within a specified time constraint. Our algorithm is particularly useful for real-time recognition of bar codes in portable hand-held devices with limited processing capability, such as mobile phones.", };


	2006


	CONFERENCES:


	16)	P. Sadeghi, T. D. Abhayapala and R. A. Kennedy, "Intrinsic finite dimensionality of random multipath fields," Proc. Int. Conf. on Acoustics Speech and Signal Processing, ICASSP'06, Toulouse, France, 2006, pp. 17-20. PDF \| bibtex
		@inproceedings{sadeghi:abhayapala:kennedy:icassp:06, Address = "Toulouse, France", Author = "Sadeghi, P. and Abhayapala, T. D. and Kennedy, R. A.", Booktitle = "Proc. Int. Conf. on Acoustics Speech and Signal Processing, ICASSP'06", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 12:09:45 +1100", Doi = "10.1109/ICASSP.2006.1660894", Era-Rank = "B", Google-Scholar = "3", Gsdoi = "0", Link = "papers/2006/ICASSP_2006.pdf", Linkname = "PDF", Month = "May", Pages = "17-20", Pdf-Url = "http://users.rsise.anu.edu.au/~rod/papers/2006/01660894.pdf", Rating = "3", Status = "Published", Title = "Intrinsic finite dimensionality of random multipath fields", Volume = "4", Year = "2006", Abstract = "We study the dimensions or degrees of freedom of random multipath fields in wireless communications. Random multipath fields are presented as solutions to the wave equation in an infinite-dimensional vector space. We prove a universal bound for the dimension of random multipath field in the mean square error sense. The derived maximum dimension is directly proportional to the radius of the two-dimensional spatial region where the field is coupled to. Using the Karhunen-Loeve expansion of multipath fields, we prove that, among all random multipath fields, isotropic random multipath achieves the maximum dimension bound. These results mathematically quantify the imprecise notion of rich scattering that is often used in multiple-antenna communication theory and show that even the richest scatterer (isotropic) has a finite intrinsic dimension.", };


	15)	P. Sadeghi, T. D. Abhayapala and R. A. Kennedy, "Directional random scattering MIMO channels: entropy analysis and capacity optimization," Proc. IEEE International Conference on Communications, ICC'06, Istanbul, Turkey, 2006, pp. 1331-1336. PDF \| bibtex
		@inproceedings{sadeghi:abhayapala:kennedy:icc:06, Address = "Istanbul, Turkey", Author = "Sadeghi, P. and Abhayapala, T. D. and Kennedy, R. A.", Booktitle = "Proc. IEEE International Conference on Communications, ICC'06", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 12:09:43 +1100", Doi = "10.1109/ICC.2006.254933", Era-Rank = "B", Google-Scholar = "2", Gsdoi = "0", Link = "papers/2006/ICC_2006.pdf", Linkname = "PDF", Month = "June", Pages = "1331-1336", Pdf-Url = "http://users.rsise.anu.edu.au/~rod/papers/2006/04024325.pdf", Rating = "3", Status = "Published", Title = "Directional Random Scattering {MIMO} Channels: Entropy Analysis and Capacity Optimization", Volume = "3", Year = "2006", Abstract = "In this paper, we study the effect of directional random scattering on the capacity of multiple-input multiple-output (MIMO) systems. First, we use the spatial decomposition of the MIMO channel matrix to analyze the randomness (entropy) of directional scattering. The analysis shows that directional scatterers (with at least a null in the angular power spectrum) will no longer be random when the receiver observation radius is sufficiently large. Therefore, directional scattering limits the expected linear increase of MIMO capacity with increasing the number of antennas. Second, we consider the effect of receiver antenna arrangement (positions) on the capacity of MIMO systems. For any random scatterer with a given angular power spectrum, we show that it is possible to choose the receiver antenna arrangement with the optimum whitening of the MIMO channel matrix that, in turn, maximizes MIMO channel capacity.", };


	14)	P. Sadeghi, P. B. Rapajic, T. D. Abhayapala and R. A. Kennedy, "Autoregressive time-varying flat-fading channels: model order and information rate bounds," Proc. International Symposium on Information Theory, ISIT 2006, Seattle, Washington, 2006, pp. 1061-1065. PDF \| bibtex
		@inproceedings{sadeghi:rapajic:kennedy:abhayapala:isit:06, Address = "Seattle, Washington", Author = "Sadeghi, P. and Rapajic, P. B. and Abhayapala, T. D. and Kennedy, R. A.", Booktitle = "Proc. International Symposium on Information Theory, ISIT 2006", Date-Added = "2011-01-20 17:47:09 +1100", Date-Modified = "2011-01-21 12:09:45 +1100", Doi = "10.1109/ISIT.2006.261890", Era-Rank = "B", Google-Scholar = "3", Gsdoi = "Yes", Link = "papers/2006/ISIT_2006.pdf", Linkname = "PDF", Month = "July", Pages = "1061-1065", Pdf-Url = "http://users.cecs.anu.edu.au/~rod/papers/2006/04036127.pdf", Rating = "3", Status = "Published", Title = "Autoregressive Time-Varying Flat-Fading Channels: Model Order and Information Rate Bounds", Year = "2006", Abstract = "In this paper, we study the effect of channel memory order on the information rate bounds in time-varying flat-fading (FF) channels. We model time variations of the FF channel with autoregressive (AR) processes with varying degrees of model order. We observe that in high SNR conditions (SNR 20 dB), the information rate penalty of not knowing the AR channel is a non-increasing function of the AR model order. This is expected, since the AR channel predictability cannot decrease with increasing its order. However, in low SNR conditions, the information rate penalty in low-order AR channels can be lower than those in high-order AR channels. Likewise, the intuitive and universal monotonic increase of the information rate bounds with the AR model order is only observed in almost noiseless conditions. In the low SNR regime, however, the achievable information rate bounds in low-order AR channels can be higher than those in high-order AR channels.", };


	13)	P. Sadeghi, J. Manton and P. Rapajic, "An information-theoretic measure for the selection of effective memory order in flat-fading channels," Proc. NEWCOM-ACORN joint workshop, Vienna, Austria, Sept. 2006. PDF \| bibtex
		@inproceedings{sadeghi:manton:rapajic:newcom:06, Address = "Vienna, Austria", Author = "Sadeghi, P. and Manton, J. and Rapajic, P.", Booktitle = "Proc. NEWCOM-ACORN joint workshop", Date-Modified = "2011-01-21 15:21:51 +1100", Era-Rank = "-", Google-Scholar = "1", Link = "papers/2006/NEWCOM_ACORN_2006.pdf", Linkname = "PDF", Month = sep, Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2006/NEWCOM_ACORN_2006.pdf", Rating = "1", Status = "Published", Title = "An Information-Theoretic Measure for the Selection of Effective Memory Order in Flat-Fading Channels", Year = "2006", Abstract = "In this paper, we consider an information-theoretic measure for the selection of effective memory order in time-varying flat-fading (FF) channels in the Jakes-Clarke's model. The measure is based on how many past realisations of the fad- ing channel actively contribute to an achievable information rate lower bound through the channel. The lower bound signifies the achievable information rate when the receiver is equipped with a sup-optimal mismatched decoding rule, which would have only been optimal for a finite-state Markov channel (FSMC) with a finite memory order. The sensitivity of the mismatched decoding rule to memory order is used to find the optimum channel memory order for decoding at the receiver side, with a negligible information rate loss. Our case study shows that the FF channel has an effective information-theoretic memory order of M=1 for the normalised fading rates f_D<=0.01, where F_D is the Doppler spread and T is symbol period. For faster fading rates, the use of first-order models at the receiver incurs a non-negligible information rate loss. The results are, generally, in accordance with our previous findings.", };


	2005


	JOURNALS AND MAGAZINES:


	12)	"Capacity analysis for finite-state Markov mapping of flat-fading channels," IEEE Trans. Commun., pp. 833-840, May 2005. PDF \| bibtex
		@article{sadeghi:rapajic:trans:com:05, Journal = "{IEEE} Trans. Commun.", Link = "papers/2005/TCOM_2005.pdf", Linkname = "PDF", Month = may, Number = "5", Pages = "833-840", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2005/TCOM_2005.pdf", Rating = "5", Status = "Published", Title = "Capacity analysis for finite-state {Markov} mapping of flat-fading channels", Volume = "53", Year = "2005", Abstract = "In this paper, time-varying flat-fading channels are modeled as first-order finite-state Markov channels (FSMC). The effect of this modeling on the channel information capacity is addressed. The approximation accuracy of the first-order memory assumption in the Markov model is validated by comparing the FSMC capacity with the channel capacity assuming perfect state information at the receiver side. The results indicate that the first-order Markovian assumption is accurate for normalized Doppler frequencies fdT &lsim 0.01, in amplitude-only quantization of the channel gain for noncoherent binary signaling. In phase-only and joint phase and amplitude quantization of the channel gain for coherent binary signaling, the first-order Markovian assumption is accurate for fdT &lsim 0.001. Furthermore, the effect of channel quantization thresholds on the FSMC capacity is studied. In high signal-to-noise ratio (SNR) conditions, nonuniform two-level amplitude quantization scheme outperforms equiprobable quantization method by 0.8-1.5 dB.", };


	CONFERENCES:


	11)	S. Krusevac, P. B. Rapajic, R. A. Kennedy and P. Sadeghi, "Mutual coupling effect on thermal noise in multi-antenna wireless communication systems," Proc. 6th Australian Communications Theory Workshop, AusCTW'2005, Brisbane, Australia, 2005, pp. 209-214. PDF \| bibtex
		@inproceedings{krusevac:rapajic:kennedy:sadeghi:ausctw:05, Address = "Brisbane, Australia", Author = "Krusevac, S. and Rapajic, P. B. and Kennedy, R. A. and Sadeghi, P.", Booktitle = "Proc. 6th Australian Communications Theory Workshop, AusCTW'2005", Date-Added = "2011-01-20 17:56:37 +1100", Date-Modified = "2011-01-21 11:21:55 +1100", Doi = "10.1109/AUSCTW.2005.1624253", Era-Rank = "-", Google-Scholar = "1", Link = "papers/2005/AUSCTW_2005.pdf", Linkname = "PDF", Month = "February", Official-Url = "http://ieeexplore.ieee.org/search/wrapper.jsp?arnumber=1624253", Pages = "209-214", Pdf-Url = "http://homepage.mac.com/rodken/PDF/C2005/01624253.pdf", Rating = "1", Status = "Published", Title = "Mutual coupling effect on thermal noise in multi-antenna wireless communication systems", Year = "2005", Abstract = "This paper presents a framework for the thermal noise analysis of mutually-coupled antennae in the multi-antenna system. The electromagnetic coupling for thermal noise is included in the analysis of the multi-antenna system with small antenna element spacings. The method for thermal noise power calculation for the multi-antenna system with coupled antennae is presented. The thermal noise behavior in the multi-antenna system is determined by applying the Nyquist's thermal noise theorem. The partial correlation of thermal noise for antenna spacing lower then a wavelength is confirmed. The signal-to-noise ratio (SNR) for the closely spaced antennae in the multi-antenna system is then estimated, using presented method for thermal noise analysis. Simulation results confirm that as the antenna spacing decreases to zero, the multi-antenna system starts to act like a single antenna system.", };


	10)	P. Sadeghi, P. B. Rapajic and Z. B. Krusevac, "The effect of memory order on the capacity of finite-state Markov and flat-fading channels," Proc. IEEE Int. Symp. on Inform. Theory (ISIT), Adelaide, Australia, Sept. 2005, pp. 525-529. PDF \| bibtex
		@inproceedings{sadeghi:rapajic:krusevac:isit:05, Address = "Adelaide, Australia", Author = "Sadeghi, P. and Rapajic, P. B. and Krusevac, Z. B.", Booktitle = "Proc. {IEEE} Int. Symp. on Inform. Theory ({ISIT})", Date-Modified = "2011-01-21 15:23:40 +1100", Doi = "10.1109/ISIT.2005.1523390", Era-Rank = "B", Google-Scholar = "3", Link = "papers/2005/ISIT_2005.pdf", Linkname = "PDF", Month = sep, Pages = "525-529", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2005/ISIT_2005.pdf", Rating = "3", Status = "Published", Title = "The effect of memory order on the capacity of finite-state {Markov} and flat-fading channels", Year = "2005", Abstract = "In this paper, we study the effect of memory order on the capacity of finite-state Markov channels (FSMC). We analytically compare the capacity of an originally high-order FSMC model with the capacity of its reduced memory order version. We show that the capacity difference is caused by two factors: 1) the channel entropy difference, and 2) the channel observability difference between the two models. While the first factor, alone, results in underestimation of the original FSMC capacity by the reduced-order FSMC model, due to the existence of the second factor, capacity overestimation can also occur. Explicit examples of FSMC models are provided, where the reduced-order FSMC model overestimates the capacity of the original high-order channel. To show the practical significance of the analysis, we model time-varying flat-fading (FF) channels with FSMC models. It is observed that the first-order FSMC models can provide both higher and lower estimates of the FF channel capacity, compared to higher order FSMC models.", };


	9)	Z. B. Krusevac, P. B. Rapajic and P. Sadeghi, "Channel estimation and differential detection for MPSK signalling in time-varying flat-fading communication channels," Proc. IEEE Veh. Technol. Conf. (VTC), Dallas, TX, Sept. 2005, pp. 1347-1351. PDF \| bibtex
		@inproceedings{krusevac:rapajic:sadeghi:vtc:05, Address = "Dallas, TX", Author = "Krusevac, Z. B. and Rapajic, P. B. and Sadeghi, P.", Booktitle = "Proc. {IEEE} Veh. Technol. Conf. (VTC)", Date-Modified = "2011-01-21 15:23:59 +1100", Doi = "10.1109/VETECF.2005.1558146", Era-Rank = "B", Google-Scholar = "2", Link = "papers/2005/VTC_2005.pdf", Linkname = "PDF", Month = sep, Pages = "1347-1351", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2005/VTC_2005.pdf", Rating = "3", Status = "Published", Title = "Channel estimation and differential detection for {MPSK} signalling in time-varying flat-fading communication channels", Year = "2005", Abstract = "This paper addresses the issue of capacity achieving reliable information transfer over time-varying flat-fading com- munication channels. We use M-state, M-ary symmetric finite- state Markov channels (FSMC) to model time variations of flat- fading channels. We analyze the conventional (separate) approach to channel parameter estimation and data detection by using decision-feedback and output-feedback FSMC estimators. Our analysis includes the metric function update analysis for the decision-feedback estimator and the mutual information rate penalty caused by the input signal entropy reduction, for the output-feedback estimation. Then, we consider the implementa- tion of differential detection instead of channel estimation. We show that differential detection transfers the memory of the channel process into a latent form, which does not interfere with the operation of standard ML coding for memoryless channels. Furthermore, we show that multiple-symbol differential detection practically achieves the channel information capacity with observation times only on the order of a few additional symbol intervals.", };


	8)	Z. B. Krusevac, P. B. Rapajic and P. Sadeghi, "Channel estimation and coding for BPSK signalling in time varying fading communication channels," Proc. Int. Symp. on Commun. Theory and Applications (ISCTA), Ambleside, Lake District, UK, July 2005, pp. 467 - 472. PDF \| bibtex
		@inproceedings{krusevac:rapajic:sadeghi:iscta:05, Address = "Ambleside, Lake District, UK", Author = "Krusevac, Z. B. and Rapajic, P. B. and Sadeghi, P.", Booktitle = "Proc. Int. Symp. on Commun. Theory and Applications (ISCTA)", Date-Modified = "2011-01-21 11:33:09 +1100", Era-Rank = "-", Google-Scholar = "0", Month = jul, Pages = "467 - 472", Rating = "1", Status = "Published", Title = "Channel estimation and coding for {BPSK} signalling in time varying fading communication channels", Year = "2005", };


	2004


	CONFERENCES:


	7)	P. Sadeghi and P. Rapajic, "Capacity performance analysis of coherent detection in correlated fading channels using finite state Markov models," Proc. IEEE Veh. Technol. Conf. (VTC), Los Angeles, CA, Sept. 2004, pp. 2158-2162. PDF \| bibtex
		@inproceedings{sadeghi:rapajic:vtc:04, Address = "Los Angeles, CA", Author = "Sadeghi, P. and Rapajic, P.", Booktitle = "Proc. {IEEE} Veh. Technol. Conf. (VTC)", Date-Modified = "2011-01-21 15:24:46 +1100", Doi = "10.1109/VETECF.2004.1400422", Era-Rank = "B", Google-Scholar = "9", Link = "papers/2004/VTC_2004.pdf", Linkname = "PDF", Month = sep, Pages = "2158-2162", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2004/VTC_2004.pdf", Rating = "3", Status = "Published", Title = "Capacity performance analysis of coherent detection in correlated fading channels using finite state {Markov} models", Year = "2004", Abstract = "In this paper, an information theoretic approach is taken to the problem of joint channel estimation and coherent data detection in time varying flat fading channels. At the receiver side, the fading phase process is partitioned or mapped into a finite state Markov channel (FSMC). Using simulation-based capacity analysis of FSMC models, accurate capacity calculation of time varying fading channels is carried out and the effect of number of channel phase partitions on the channel capacity performance is studied. In the BPSK scheme, the capacity is saturated beyond 8 to 16 channel phase partitions. In QPSK signalling, the channel capacity gap between 16/32 channel phase partitions and 128 channel phase partitions is less than 0.3 dB. Moreover, the capacity performance of BPSK and QPSK in unknown correlated fading is compared. The comparison reveals that to maintain the superior QPSK capacity performance, care must be taken in the choice of average transmitted power and symbol duration.", };


	6)	P. Sadeghi and P. Rapajic, "Analysis of pilot symbol assisted modulation in fading channels using finite state Markov models," Proc. IEEE Int. Symp. on Spread Spectrum and it Applications (ISSSTA), Sydney, Australia, Aug. 2004, pp. 458-461. PDF \| bibtex
		@inproceedings{sadeghi:rapajic:isssta:04, Address = "Sydney, Australia", Author = "Sadeghi, P. and Rapajic, P.", Booktitle = "Proc. {IEEE} Int. Symp. on Spread Spectrum and it Applications (ISSSTA)", Date-Modified = "2011-01-21 15:25:01 +1100", Doi = "10.1109/ISSSTA.2004.1371742", Era-Rank = "-", Google-Scholar = "0", Link = "papers/2004/ISSSTA_2004.pdf", Linkname = "PDF", Month = aug, Pages = "458-461", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2004/ISSSTA_2004.pdf", Rating = "1", Status = "Published", Title = "Analysis of Pilot Symbol Assisted Modulation in Fading Channels Using Finite State {Markov} Models", Year = "2004", Abstract = "We present an analysis for channel state estimation and coherent data detection in pilot symbol assisted modulation (PSAM), which is based on the maximum a posteriori (MAP) criterion. The time varying fading channel is modelled as the finite state Markov channel (FSMC). The exact channel state estimation error probability is analyzed, using the forward recursion in the forward-backward algorithm. The effect of channel state estimation error probability on the receiver symbol error rate (SER) performance in an M-ary phase shift keying (PSK) scheme is formulated. The analysis is applied for different channel phase quantization levels and various pilot symbol numbers. The results indicate that BPSK SER performance is saturated with more than 8 to 16 levels of channel phase quantization. For a QPSK scheme, 16 levels of channel phase quantization are adequate. Moreover, the transmission of 3 consecutive pilot symbols achieves an acceptable SER performance.", };


	5)	P. Sadeghi, P. B. Rapajic and S. J. Johnson, "Numerical capacity analysis for time varying fading channels using finite state Markov models," Proc. IEEE Int. Symp. on Inform. Theory (ISIT), Chicago, IL, June 2004, pp. 180. PDF \| bibtex
		@inproceedings{sadeghi:rapajic:johnson:isit:04, Address = "Chicago, IL", Author = "Sadeghi, P. and Rapajic, P. B. and Johnson, S. J.", Booktitle = "Proc. {IEEE} Int. Symp. on Inform. Theory ({ISIT})", Date-Modified = "2011-01-21 15:25:24 +1100", Doi = "10.1109/ISIT.2004.1365216", Era-Rank = "B", Google-Scholar = "1", Link = "papers/2004/ISIT_2004.pdf", Linkname = "PDF", Month = jun, Pages = "180", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2004/ISIT_2004.pdf", Rating = "3", Status = "Published", Title = "Numerical capacity analysis for time varying fading channels using finite state {Markov} models", Year = "2004", Abstract = "The effect of channel gain quantization on the information capacity of unknown time varying flat fading channels is investigated. The phase and/or amplitude of the flat fading channel gain is modelled as a finite state Markov (FSM) process and the information capacity of the FSM channel is calculated numerically as a measure for choosing the number of channel quantization levels, as well as quantization thresholds. The results indicate that for binary signalling, the capacity is saturated beyond 8 to 16 levels of phase and 8 to 16 levels of amplitude quantization.", };


	2003


	CONFERENCES:


	4)	P. Sadeghi and P. B. Rapajic, "Comparison of receiver training methods in joint iterative channel estimation and data decoding in flat fading channels," Proc. IEEE Int. Symp. on Personal, Indoor, and Mobile Radio Communications (PIMRC), Beijing, China, Sept. 2003, pp. 717-721. PDF \| bibtex
		@inproceedings{sadeghi:rapajic:pimrc:03, Address = "Beijing, China", Author = "Sadeghi, P. and Rapajic, P. B.", Booktitle = "Proc. {IEEE} Int. Symp. on Personal, Indoor, and Mobile Radio Communications ({PIMRC})", Date-Modified = "2011-01-21 15:25:39 +1100", Doi = "10.1109/PIMRC.2003.1264367", Era-Rank = "-", Google-Scholar = "3", Link = "papers/2003/PIMRC_2003.pdf", Linkname = "PDF", Month = sep, Pages = "717-721", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2003/PIMRC_2003.pdf", Rating = "1", Status = "Published", Title = "Comparison of receiver training methods in joint iterative channel estimation and data decoding in flat fading channels", Volume = "1", Year = "2003", Abstract = "In this paper we compare two different methods for receiver training in flat fading channels. The first method is the traditional way in which periodic training sequences are sent to the receiver (explicit training). In the second method, recently proposed, the information source emits bits with unequal probabilities of being '0' and '1'. This method is called implicit training, since the training is implied in the non-symmetrical source structure. BPSK signaling is used as the simplest example of constant-envelope phase modulations. We map the phase component of the flat fading channel response to a simple two-state Markov model. Then joint iterative trellis-based maximum a posteriori probability (MAP) method is used for channel state estimation and decoding. The results of computer simulations for the receiver bit error rate (BER) performance in various channel fading rates and information rates are presented. The results indicate superior performance of implicit training. In slow fading conditions, the gain is 4 dB at information rate of 0.15 bits/channel use and 1.2 dB for information rate of 0.25 bits/channel use.", };


	3)	P. Sadeghi, V. Trajkovic and P. Rapajic, "Implicit and explicit receiver training in flat fading channels modeled as finite state Markov processes," Proc. IEEE Int. Symp. on Inform. Theory (ISIT), Yokohama, Japan, June 2003, pp. 95. PDF \| bibtex
		@inproceedings{sadeghi:rapajic:isit:03, Address = "Yokohama, Japan", Author = "Sadeghi, P. and Trajkovic, V. and Rapajic, P.", Booktitle = "Proc. {IEEE} Int. Symp. on Inform. Theory ({ISIT})", Date-Modified = "2011-01-21 15:25:54 +1100", Doi = "10.1109/ISIT.2003.1228109", Era-Rank = "B", Google-Scholar = "4", Link = "papers/2003/ISIT_2003.pdf", Linkname = "PDF", Month = jun, Pages = "95", Pdf-Url = "http://users.cecs.anu.edu.au/~parastoo/papers/2003/ISIT_2003.pdf", Rating = "3", Status = "Published", Title = "Implicit and explicit receiver training in flat fading channels modeled as finite state {Markov} processes", Year = "2003", Abstract = "We study the effect of training method on the receiver bit error rate (BER) performance in constant envelope phase modulation schemes that are transmitted through flat fading channels. Here we propose a novel method for receiver training by sending information bits with unbalanced probabilities. We call this method implicit training and compare it with traditional (explicit) training scheme in which known periodic training sequences are sent to the receiver. The simulation results show superior performance of implicit training where the gain is 2 dB at information rate of 0.15 bits/channel use.", };


	2)	P. Sadeghi and P. B. Rapajic, "Capacity measure for finite state Markov modeling of the phase process in flat fading channels," Proc. Int. Conf. Telecommun. (ICT), Papeete, Tahiti, Feb. 2003, pp. 572-577. PDF \| bibtex
		@inproceedings{sadeghi:rapajic:ict:03, Address = "Papeete, Tahiti", Author = "Sadeghi, P. and Rapajic, P. B.", Booktitle = "Proc. Int. Conf. Telecommun. ({ICT})", Date-Modified = "2011-01-21 12:09:56 +1100", Doi = "10.1109/ICTEL.2003.1191473", Era-Rank = "C", Google-Scholar = "1", Month = feb, Pages = "572-577", Rating = "2", Status = "Published", Title = "Capacity measure for finite state {Markov} modeling of the phase process in flat fading channels", Volume = "1", Year = "2003", Abstract = "We investigate finite state Markov modeling of the phase process in flat fading channels. Phase modulations are often used in mobile communication systems. They rely on the fact that the receiver can estimate the channel phase with acceptable accuracy. In the absence of pilot signals or when the channel varies frequently, this becomes a very challenging task. Inaccuracy in phase estimation results in dramatic performance degradation. We propose mapping of the channel phase process into a finite state Markov model. In particular, we study the effect of the number of phase quantization levels and thresholds on the capacity under different signal-to-noise ratio and fading correlation conditions. In BPSK signaling, non-uniform 4-state phase quantization results in noticeable capacity enhancement under all signal-to-noise and fading correlation conditions, while in low signal-to-noise conditions, the 8-state channel outperforms the 4-state channel slightly. Both constant envelope and Rayleigh envelope models are considered in the numerical capacity analyses. The capacity improvements are also compared with the improvements in finite state Markov mapping of the fading envelope.", };


	2002


	CONFERENCES:


	1)	P. Sadeghi and P. B. Rapajic, "Capacity measure for finite state Markov modeling of Rayleigh fading channels," Proc. Int. Symp. on Inform. Theory and Its Applications (ISITA), Beijing, China, Oct. 2002, pp. 607-610. PDF \| bibtex
		@inproceedings{sadeghi:rapajic:isita:02, Address = "Beijing, China", Author = "Sadeghi, P. and Rapajic, P. B.", Booktitle = "Proc. Int. Symp. on Inform. Theory and Its Applications ({ISITA})", Date-Modified = "2011-01-21 12:09:44 +1100", Era-Rank = "B", Google-Scholar = "3", Month = oct, Pages = "607-610", Rating = "3", Status = "Published", Title = "Capacity measure for finite state {Markov} modeling of {Rayleigh} fading channels", Year = "2002", };

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