Approximate Rate Adaptation for MIMO-OFDM Systems with Delayed Feedback

We present an approximate rate adaptation algorithm for MIMO spatial multiplexing transmission over multiple time-variant subchannels, based on delayed inaccurate feedback. The algorithm exploits an approximation to the mutual-information-averaged post-equalization signal-to-interference-and-noise- ratio statistics. It is suited for linear and successive interference cancelation MIMO receivers. We demonstrate that the algorithm successfully exploits frequency diversity in order to mitigate the rate loss at increasing velocities. In addition, the interference cancelation receiver gain, as compared to linear receivers, can be maintained even with error propagation.