On the Performance of Orthogonal Space-Time Block Codes over Independent, Nonidentical Rayleigh/Ricean Fading Channels

We consider the bit error performance of orthogonal space-time block codes (STBC) over independent, non-identically distributed, Rayleigh/Ricean, block fading channels with perfect channel state information. With symbol-by-symbol detection, we derive the expressions for the exact bit error probability (BEP) in both Rayleigh and Ricean fading channels. The results are applicable to any number of transmit and receive antennas for which orthogonal STBC's are defined. A simple but insightful upper bound on the BEP is also obtained. From the expressions of the BEP, we find that in Rayleigh channels, the nonidentical distributions degrade the performance. However, for Ricean case, the nonidentical distributions can have different effects on the performance.