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Unitary Matrix Design via Genetic Search for Differential Space-Time Modulation and Limited Feedback Precoding

A. Ghaderipoor, M. Hajiaghayi, C. Tellambura
2006 2006 IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications  
For DUSTM and limited feedback MIMO systems, a codebook of unitary matrices should be designed. Conventionally, design parameters are optimized based on a cost function depending on the application.  ...  In multipleinput multiple-output (MIMO) communication systems, there are two main applications that use unitary matrices: differential space-time modulation (DUSTM) and precoding.  ...  : cyclic group design and cyclic-rotated design.  ... 
doi:10.1109/pimrc.2006.253935 dblp:conf/pimrc/GhaderipoorHT06 fatcat:u4ce77ogrzc25g5lgwg6xyh4va

Improved Differential Unitary Space-Time Signal Design for Two to Six Transmit Antennas

D. Smith
2006 2006 IEEE International Conference on Communications  
We demonstrate that the union bound on the block error probability of DUSTM codes can be considerably simplified for various cases of non-group DUSTM constellations.  ...  This paper addresses optimization of differential unitary space-time modulation (DUSTM) for more than two transmit antennas.  ...  ACKNOWLEDGMENT The author thanks Thushara D. Abhayapala for reading this paper and providing some helpful comments and insights.  ... 
doi:10.1109/icc.2006.254923 dblp:conf/icc/Smith06 fatcat:2dwdomuxbbgd3dvszsosdez6ly

Optimum Design of Differential Unitary Space-Time Modulation

Mahdi Hajiaghayi, Chintha Tellambura
2006 IEEE Vehicular Technology Conference  
In this paper, we propose an extended class of unitary signal constellations for differential unitary space-time modulation (DUSTM).  ...  We also derive an approximation of the upper bound on the symbol error probability (SEP) as a general criterion to find the optimum codes.  ...  Without loss of generality, we focus here on designing optimum DUST codes based on proposed constellation in section (III) and non-group constellation in [10] .  ... 
doi:10.1109/vtcf.2006.118 dblp:conf/vtc/HajiaghayiT06 fatcat:lgxzou2w65bvvhyvlidoo3kbyy

Orthogonal delay diversity realization and cyclic group codes for MIMO-OFDM

Yao Chen, U. Tureli, E. Aktas
2004 2004 IEEE International Conference on Communications (IEEE Cat. No.04CH37577)  
A delayed space-frequency cyclic group code is proposed in this paper, which applies a new bandwidth and powerefficient space-frequency processing on the orthogonal-frequencydivision-multiplexing (OFDM  ...  Without a tradeoff of the diversity gain, the proposed code can be easily expanded to achieve high data rate and generalized to more than two transmit antennas.  ...  R , every full-rank unitary space-time group G is equivalent to an (M ; h 1 , · · · , h N ) cyclic or dicyclic code.  ... 
doi:10.1109/icc.2004.1312492 dblp:conf/icc/ChenTA04 fatcat:samqomqrbrhdjnaiyriddoq4ly

Matrix rotation based signal design for differential unitary space-time modulation

Thanongsak Himsoon, Weifeng Su, K.J. Ray Liu
2004 2004 IEEE Wireless Communications and Networking Conference (IEEE Cat. No.04TH8733)  
In this paper, we consider the design of Matrix Rotation Based (MRB) space-time signals based on the design criterion of minimizing the union bound on pairwise block error probability (P BEP ).  ...  With our proposed design for two transmit antennas and one or two receive antennas, we achieve the coding gain of about 1 dB over that of the previous design. 0-7803-8344-3/04/$20.00  ...  The proposed design of unitary space-time signals in [6] , [7] is based on minimizing pairwise block error probability (P BEP ).  ... 
doi:10.1109/wcnc.2004.1311656 dblp:conf/wcnc/HimsoonSL04 fatcat:6dfh2dp6sfbppf7w3wqimwpmui

Differential unitary space-time signal design using matrix rotation structure

T. Himsoon, Weifeng Su, K.J. Ray Liu
2005 IEEE Signal Processing Letters  
We consider the design of matrix rotation based space-time signals based on the design criterion of minimizing the union bound on block error probability.  ...  With our proposed design for two transmit antennas and one or two receive antennas, we achieve the coding gain of about 1 dB over that of the previous design.  ...  The proposed design of unitary space-time signals is based on minimizing pairwise block error probability (PBEP).  ... 
doi:10.1109/lsp.2004.838196 fatcat:yoqsajpu4bdzlessh6oxv7haim

A Gray-Code Type Bit Assignment Algorithm for Unitary Space-Time Constellations

Adam Panagos, Kurt Kosbar
2007 IEEE GLOBECOM 2007-2007 IEEE Global Telecommunications Conference  
The algorithm can be used on constellations constructed using any technique.  ...  This work proposes a prioritized distance (PD) algorithm for making this assignment in an optimal manner by minimizing the probability of bit error union bound.  ...  Cyclic unitary space-time constellations [2] and Weak Group Givens codes [10] were used to investigate the performance of the proposed PD bit assignment algorithm.  ... 
doi:10.1109/glocom.2007.761 dblp:conf/globecom/PanagosK07 fatcat:daxpcvvehbesddxsodszz4p7fe

Differential space-time modulation over frequency-selective channels

Hongbin Li
2005 IEEE Transactions on Signal Processing  
A unitary structure is imposed on the differential encoder to admit linear, decoupled maximum likelihood (ML) detection in space and time.  ...  Optimum criteria based on pairwise error probability analysis are developed for spectral encoder design.  ...  Differential modulation is performed on each subcarrier using the cyclic group differential space-time codes [9] , which encode across space and time but not frequency. • DSTF-NSE: The proposed DSTF modulation  ... 
doi:10.1109/tsp.2005.847853 fatcat:buvfuk7zfjf2tbiixr2gcxelty

Unitary Space–Time Codes From Alamouti's Scheme With APSK Signals

A. Song, G. Wang, W. Su, X.-G. Xia
2004 IEEE Transactions on Wireless Communications  
Unitary space-time codes have been used in differential space-time modulation, when neither the transmitter nor the receiver of a multiple antenna system knows the channel state information in Rayleigh  ...  Among the codes in literature, unitary orthogonal space-time codes, constructed from Alamouti's scheme, have the advantage of fast maximum likelihood (ML) decoding but they require signal constellations  ...  There are many constructions of unitary space-time codes in the literature, for example, diagonal codes [1] , [2] , dicyclic codes [2] , [4] fixed-point-free group unitary codes [5] , Manuscript  ... 
doi:10.1109/twc.2004.837277 fatcat:jcntmxyizrcsvgatgrruja6rtu

Differential Space-Time Coding Scheme Using Star Quadrature Amplitude Modulation Method

Xiangbin Yu, DaZhuan Xu, Guangguo Bi
2006 EURASIP Journal on Advances in Signal Processing  
One is based on differential unitary space-time coding (DUSTC) scheme, and the other is based on differential orthogonal space-time coding (DOSTC) scheme.  ...  Differential space-time coding (DSTC) has received much interest as it obviates the requirement of the channel state information at the receiver while maintaining the desired properties of space-time coding  ...  The authors would like to thank the two anonymous reviewers for their useful comments and constructive suggestions throughout the course of reviewing this paper, and thank Prof.  ... 
doi:10.1155/asp/2006/89849 fatcat:axmtjvn5sne3bmxt5wbmo63r44

Partially-coherent distributed space-time codes with differential encoder and decoder

Kiran T., B. Rajan
2007 IEEE Journal on Selected Areas in Communications  
Distributed space-time coding is a mean of achieving diversity through cooperative communication in a wireless relay network.  ...  For such a setup, we derive a Chernoff bound on the pairwise error probability and propose code design criteria.  ...  ACKNOWLEDGMENT The authors thank Dr. F. Oggier for sending a copy of her paper. They are grateful to the reviewers for their comments which helped to improve the paper considerably.  ... 
doi:10.1109/jsac.2007.070217 fatcat:6qpnayxjafhllofiefqyky356m

Partially-Coherent Distributed Space-Time Codes with Differential Encoder and Decoder

T. Kiran, B. Rajan
2006 2006 IEEE International Symposium on Information Theory  
Distributed space-time coding is a mean of achieving diversity through cooperative communication in a wireless relay network.  ...  For such a setup, we derive a Chernoff bound on the pairwise error probability and propose code design criteria.  ...  ACKNOWLEDGMENT The authors thank Dr. F. Oggier for sending a copy of her paper. They are grateful to the reviewers for their comments which helped to improve the paper considerably.  ... 
doi:10.1109/isit.2006.261776 dblp:conf/isit/KiranR06a fatcat:rc7kojapqfbvvc3igwdwkl2k7u

Full-rate full-diversity space-frequency codes with optimum coding advantage

Weifeng Su, Z. Safar, K.J. Ray Liu
2005 IEEE Transactions on Information Theory  
We show that the diversity product can be decomposed as the product of the "intrinsic" diversity product, which depends only on the used signal constellation and the code design, and the "extrinsic" diversity  ...  product, which depends only on the applied interleaving method and the power delay profile of the channel.  ...  Assuming that the delay paths are equally spaced and fall onto the sampling instances of the receiver, an optimum subcarrier grouping method was proposed in [36] .  ... 
doi:10.1109/tit.2004.839496 fatcat:ueiwufr5ibbofiwdo6uue42r3a

Space-time-frequency (STF) coding for MIMO-OFDM systems

A.F. Molisch, M.Z. Win, J.H. Winters
2002 IEEE Communications Letters  
An optimum code would thus code across all antennas and tones (as well as time) simultaneously.  ...  This similarity immediately allows us to essentially reuse all space-time codes designed for flat-fading channels in MIMO-OFDM systems operating in frequency-selective channels.  ...  They also thank the anonymous reviewers for helpful suggestions, especially for pointing out the analogy between antennas and block codes.  ... 
doi:10.1109/lcomm.2002.802047 fatcat:n5upct5x55gyfgmmcsvmv43dam

Single-block differential transmit scheme for broadband wireless MIMO-OFDM systems

T. Himsoon, Weifeng Su, K.J. Ray Liu
2006 IEEE Transactions on Signal Processing  
The design criteria reveal that the existing diagonal cyclic codes can be applied to achieve full diversity.  ...  In frequency-selective multiple-input multiple-output (MIMO) channel, differential space-time-frequency (DSTF) modulations are known as practical alternatives that are capable of exploiting the available  ...  During the review process, one of the reviewers brought to the authors' attention an independent work [30] . 1  ... 
doi:10.1109/tsp.2006.877645 fatcat:l64ooqr5wffr3ii4pqnydbdz7m
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