Transmitter Noise Effect on the Performance of a MIMO-OFDM Hardware Implementation Achieving Improved Coverage

This paper presents analysis of performance measurements from a MIMO-OFDM IEEE 802.11n hardware implementation at 5.2 GHz using four transmitters and four receivers. Two spatial multiplexing systems are compared; one which uses a zero-forcing (ZF) detector and the other a list sphere detector (LSD). We show that the measured results do not align with standard prediction based on simulation assuming uncorrelated receiver noise. We show that the discrepancy can be explained by the inclusion of transmitter noise into the channel model. This effect is not included in existing MIMO-OFDM channel models. The measured results from our hardware implementation show successful packet transmission at 600 Mb/s with 15 bits/s/Hz spectral efficiency at 73% coverage for ZF and 84% coverage for LSD with an average receiver signal to noise ratio (SNR) of 26 dB.

[1]  G. Santella,et al.  A hybrid analytical-simulation procedure for performance evaluation in M-QAM-OFDM schemes in presence of nonlinear distortions , 1998 .

[2]  Stephan ten Brink,et al.  Achieving near-capacity on a multiple-antenna channel , 2003, IEEE Trans. Commun..

[3]  Jinhong Yuan,et al.  Performance of MIMO-OFDM-BICM on Measured Indoor Channels , 2006, 2006 IEEE 63rd Vehicular Technology Conference.

[4]  S. Reisenfeld,et al.  Optimal quantization of OFDM at digital IF , 2008, TENCON 2008 - 2008 IEEE Region 10 Conference.

[5]  X. Jin.  Factor graphs and the Sum-Product Algorithm , 2002 .

[6]  Davide Dardari,et al.  Joint clip and quantization effects characterization in OFDM receivers , 2006, IEEE Transactions on Circuits and Systems I: Regular Papers.

[7]  Robert G. Gallager,et al.  Low-density parity-check codes , 1962, IRE Trans. Inf. Theory.

[8]  Iain B. Collings,et al.  A zero-forcing approximate log-likelihood receiver for MIMO bit-interleaved coded modulation , 2004, IEEE Communications Letters.

[9]  Sanjiv Nanda,et al.  A high-performance MIMO OFDM wireless LAN , 2005, IEEE Communications Magazine.

[10]  Hiroyuki Kawai,et al.  Experiments on real-time 1-Gb/s packet transmission using MLD-based signal detection in MIMO-OFDM broadband radio access , 2006, IEEE Journal on Selected Areas in Communications.

[11]  H. Bölcskei,et al.  MIMO-OFDM wireless systems: basics, perspectives, and challenges , 2006, IEEE Wireless Communications.

[12]  Tim C. W. Schenk,et al.  Implementation of a MIMO OFDM-based wireless LAN system , 2004, IEEE Transactions on Signal Processing.

[13]  Iain B. Collings,et al.  Characteristics of MIMO-OFDM Channels in Indoor Environments , 2007, EURASIP J. Wirel. Commun. Netw..

[14]  Elena Costa,et al.  M-QAM-OFDM system performance in the presence of a nonlinear amplifier and phase noise , 2002, IEEE Trans. Commun..

[15]  Sync TGn.  TGn Sync Proposal Technical Specification , 2004 .

[16]  Iain B. Collings,et al.  Implementation of 4X4 MIMO-OFDM-LDPC for 600 Mbps packet transmission , 2006 .

[17]  Mark Hedley,et al.  Design Criteria of MIMO Systems , 2006, 2006 IEEE 63rd Vehicular Technology Conference.

[18]  Matthew R. McKay,et al.  Capacity and performance of MIMO-BICM with zero-forcing receivers , 2005, IEEE Transactions on Communications.

[19]  M. Hedley,et al.  Computational efficiency of list sphere detection , 2006, 2006 Australian Communications Theory Workshop.

[20]  Philippe Loubaton,et al.  MIMO channel blind identification in the presence of spatially correlated noise , 2002, IEEE Trans. Signal Process..

[21]  Geoffrey Ye Li,et al.  Broadband MIMO-OFDM wireless communications , 2004, Proceedings of the IEEE.

[22]  H. Suzuki,et al.  Real-time wideband MIMO demonstrator , 2007, 2007 International Symposium on Communications and Information Technologies.

[23]  Brett T. Walkenhorst,et al.  Implementation and experimental results of a three-transmitter three-receiver OFDM/BLAST testbed , 2004, IEEE Communications Magazine.

[24]  Aris L. Moustakas,et al.  MIMO capacity through correlated channels in the presence of correlated interferers and noise: a (not so) large N analysis , 2003, IEEE Trans. Inf. Theory.