An enhanced echo MIMO channel estimation method

An echo channel estimation method in the multi-input multi-output(MIMO) system under the frequency-flat fading channel is presented. The key idea of echo MIMO estimation method is to reflect, or “echo”, back the received training signal to the transmitter. But the noise reflected back to the BS together with the training signal will critically decrease the accuracy of channel estimation. In this paper, we propose a preprocessing method, which can eliminate the impact of noise, before reflecting back the training signal to solve this problem. Moreover, based on Kronecker channel model, different designs of preprocessing matrix are proposed under different antenna configuration, which will result in different estimation performance. Simulation results show that the enhanced echo MIMO channel estimation method could effectively decrease the mean square errors (MSEs) of channel estimation.