A novel channel identification method for fast wireless communication systems with transmitter and receiver diversity

In a recent paper we had enunciated a novel dual channel identification approach for fast time-varying wireless communication systems. Unlike traditional identification methods that rely on training symbols, our method involved a bent-pipe feedback mechanism which requires the mobile unit to send portions of its received signal back to the transmitter for wireless channel identification. We introduced an effective algorithm that can identify both the forward and the reverse channels based only on this feedback information without reverse-link training, provided both the links were single input single output (SISO). To capture receiver and transmitter diversity, in this paper we extend these ideas to settings where both the links are potentially multiple input multiple output (MIMO).