Level Crossing Rates of MIMO-MRC Ricean Channels and Their Implications on Adaptive Systems

Abstract

The second-order statistics of the time varying signal to noise ratio at the output of a multiple-input-multiple-output (MIMO) system with maximal ratio combining (MRC) are analyzed. Exact closed-form expressions for the level crossing rate and the average fade duration are derived for the Ricean propagation and arbitrary channel matrix dimensions. Novel expressions are compared with the special case of MRC receive diversity. The analytical results are validated by simulation.

Signal power variation with applications to cognitive radio

“…The following integrals over x , y can be performed by using the polar coordinates, x = r cos θ, y = r sin θ. The final resulting integral is solely a function of d = x 2 + y 2 and gives the final result in (12).…”

“…the level crossing rate (LCR) of signal strength across a given threshold is particularly useful in CR analysis. LCR analysis for Rayleigh fading [10], [11] is very well known and more recently, exact [12] and approximate [13] results have appeared for the LCRs of multiple-input multiple-output (MIMO) eigenvalues. For shadow fading, an excellent LCR analysis is given in [14].…”