QOSTBC coded MIMO system with reduced complexity and optimised decoding for rank deficient channels

In multiple-input multiple-output (MIMO) systems, rank deficient channels are the most common and key areas of research. In these channels, the number of transmit antennas (M Tx) is higher than receive antennas (M Rx) and subsequently the unknown variables are more than the number of equations. In such situations, the conventional sphere decoder (SD) fails due to the presence of zero diagonal elements in Cholesky decomposition. This study analyses the quasi-orthogonal space-time block code (QOSTBC) of symbol rate-2 for M Tx = 4 with modified double-layer SD detection to overcome rank deficiency problem. The first half of transmitted symbols is detected using two partially dependent SDs with optimised search radii. The remaining half is detected by employing single symbol maximum likelihood detection. Simulation and analytical results indicate that the proposed detection scheme reduces bit error rate and complexity compared to existing techniques.

[1]  Xiaoli Xu,et al.  Degrees of Freedom of the Three-User Rank-Deficient MIMO Interference Channel , 2012, IEEE Transactions on Wireless Communications.

[2]  Zongkai Yang,et al.  A new approach for fast generalized sphere decoding in MIMO systems , 2005, IEEE Signal Process. Lett..

[3]  Reinaldo A. Valenzuela,et al.  Simplified processing for high spectral efficiency wireless communication employing multi-element arrays , 1999, IEEE J. Sel. Areas Commun..

[4]  Mostafa Shahabinejad,et al.  A New Approach to Fast Decode Quasi-Orthogonal Space-Time Block Codes , 2015, IEEE Transactions on Wireless Communications.

[5]  Jingxian Wu,et al.  Two-Stage List Sphere Decoding for Under-Determined Multiple-Input Multiple-Output Systems , 2013, IEEE Transactions on Wireless Communications.

[6]  Hamid Jafarkhani,et al.  Quasi-Orthogonal Space-Frequency and Space-Time-Frequency Block Codes for MIMO OFDM Channels , 2008, IEEE Transactions on Wireless Communications.

[7]  Davinder S. Saini,et al.  A Rate $$\text{ M }_{\mathrm{T}}$$ Full Diversity STF Block Coded $$4\times 4$$ MIMO-OFDM System with Reduced Complexity , 2013, Wirel. Pers. Commun..

[8]  Siavash M. Alamouti,et al.  A simple transmit diversity technique for wireless communications , 1998, IEEE J. Sel. Areas Commun..

[9]  Giuseppe Caire,et al.  On maximum-likelihood detection and the search for the closest lattice point , 2003, IEEE Trans. Inf. Theory.

[10]  Yide Wang,et al.  Robust Fixed-Complexity Sphere Decoders for Rank-Deficient MIMO Systems , 2013, IEEE Transactions on Wireless Communications.

[11]  Hamid Jafarkhani.  A quasi-orthogonal space-time block code , 2001, IEEE Trans. Commun..

[12]  Louay M. A. Jalloul,et al.  Performance of the 3GPP LTE Space–Frequency Block Codes in Frequency-Selective Channels With Imperfect Channel Estimation , 2015, IEEE Transactions on Vehicular Technology.

[13]  M. O. Damen,et al.  Generalised sphere decoder for asymmetrical space-time communication architecture , 2000 .

[14]  Chungyong Lee,et al.  A simplified adaptive modulation scheme for D-STTD systems with linear receivers , 2005, IEEE Communications Letters.

[15]  Davinder S. Saini,et al.  Multiple Rake Combiners and Performance Improvement in 3G and Beyond WCDMA Systems , 2009, IEEE Transactions on Vehicular Technology.

[16]  Davinder S. Saini,et al.  Space–Time/Space–Frequency/Space–Time–Frequency Block Coded MIMO-OFDM System with Equalizers in Quasi Static Mobile Radio Channels Using Higher Tap Order , 2013, Wirel. Pers. Commun..

[17]  Il-Min Kim,et al.  Fast ML Detection for Quasi-Orthogonal STBCs of Rate 2 in Under-Determined Systems [Transactions Papers] , 2008, IEEE Transactions on Communications.

[18]  John S. Thompson,et al.  Extending a Fixed-Complexity Sphere Decoder to Obtain Likelihood Information for Turbo-MIMO Systems , 2008, IEEE Transactions on Vehicular Technology.

[19]  David Gesbert,et al.  From theory to practice: an overview of MIMO space-time coded wireless systems , 2003, IEEE J. Sel. Areas Commun..

[20]  Inbar Fijalkow,et al.  Analysis of One-Bit Quantized Precoding for the Multiuser Massive MIMO Downlink , 2016, IEEE Transactions on Signal Processing.

[21]  Chintha Tellambura,et al.  An efficient generalized sphere decoder for rank-deficient MIMO systems , 2004, IEEE 60th Vehicular Technology Conference, 2004. VTC2004-Fall. 2004.

[22]  Tho Le-Ngoc,et al.  A low-complexity generalized sphere decoding approach for underdetermined linear communication systems: performance and complexity evaluation , 2009, IEEE Transactions on Communications.

[23]  Davinder S. Saini,et al.  Moment generating function-based pairwise error probability analysis of concatenated low density parity check codes with Alamouti coded multiple input multiple output-orthogonal frequency division multiplexing systems , 2014, IET Commun..

[24]  Chau Yuen,et al.  Quasi-orthogonal STBC with minimum decoding complexity , 2005, IEEE Transactions on Wireless Communications.

[25]  Lajos Hanzo,et al.  Generic iterative search-centre-shifting K-best sphere detection for rank-deficient SDM-OFDM systems , 2008 .

[26]  Alex B. Gershman,et al.  A Low Complexity Decoder for Quasi-Orthogonal Space Time Block Codes , 2011, IEEE Transactions on Wireless Communications.