Generalized principal ratio combining for space-time codes in slowly fading channels

We present a generalized version of principal ratio combining (PRC), which is a near-optimum detection scheme for space-time codes in quasistatic flat fading environments. In Tarokh and Lo (1998), the performance penalty increases as the number of receive antennas increases. In the proposed scheme, receive antennas are optimally grouped by K, and the PRC detection method is applied to each group. This shows a flexible tradeoff between performance and decoding complexity by choosing the appropriate K.