On the use of Jensen's inequality for MIMO channel capacity estimation

We derive a universal upper bound on the MIMO channel capacity, which is not limited to a particular scenario, using the correlation matrix approach and the Jensen's inequality. This bound accounts for both transmit and receive branch correlation in such a way that the impact of these branches can be estimated separately, which simplifies the procedure substantially. Some simple analytical results, which quantify the impact of correlation on the MIMO capacity in an explicit way, are given. We show that correlation increase is equivalent to SNR decrease in some cases. Finally, we discuss the paradox of zero correlation and provide a statistical explanation for it. We demonstrate why zero mean correlation is not a guarantee of high capacity. The mean magnitude or RMS correlation should be used for the capacity estimation of degenerate MIMO channels.

[1]  S. Loyka,et al.  Channel capacity of n-antenna BLAST architecture , 2000 .

[2]  Gerard J. Foschini,et al.  Layered space-time architecture for wireless communication in a fading environment when using multi-element antennas , 1996, Bell Labs Technical Journal.

[3]  Sergey L. Loyka,et al.  Channel capacity of MIMO architecture using the exponential correlation matrix , 2001, IEEE Communications Letters.

[4]  Emre Telatar,et al.  Capacity of Multi-antenna Gaussian Channels , 1999, Eur. Trans. Telecommun..

[5]  M. J. Gans,et al.  On Limits of Wireless Communications in a Fading Environment when Using Multiple Antennas , 1998, Wirel. Pers. Commun..

[6]  J. H. Winters,et al.  Multiple-input multiple-output (MIMO) radio channel measurements , 2000, Proceedings of the 2000 IEEE Sensor Array and Multichannel Signal Processing Workshop. SAM 2000 (Cat. No.00EX410).

[7]  Sergey Loyka.  Channel capacity of two-antenna BLAST architecture , 1999 .

[8]  R. Valenzuela,et al.  Capacities of multi-element transmit and receive antennas: Correlations and keyholes , 2000 .

[9]  C.C. Martin,et al.  Multiple-input multiple-output (MIMO) radio channel measurements , 2001, IEEE Antennas and Propagation Society International Symposium. 2001 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.01CH37229).

[10]  Joseph M. Kahn,et al.  Fading correlation and its effect on the capacity of multielement antenna systems , 2000, IEEE Trans. Commun..

[11]  Thomas M. Cover,et al.  Elements of Information Theory , 2005 .

[12]  W. C. Jakes,et al.  Microwave Mobile Communications , 1974 .

[13]  Reinaldo A. Valenzuela,et al.  Detection algorithm and initial laboratory results using V-BLAST space-time communication architecture , 1999 .