Multi-user Precoding Technology Discovery Of MIMO System

The precoding is a transmit signal preprocessing technique, through the use of channel state information to adapt the appropriate channel conditions to improve system performance. The key problems of the precoding technology can be described as:how to exploit CSI, and how to process with CSI. This dissertation aims to discuss the second question.How to access to CSI have two modes:feedback and reciprocity.According to its accuracy, CSI can be divided into three categories:ideal CSIR and ideal CSIT; ideal CSIR and part statistical CSIT; part statistical CSIR and ideal CSIT.In the paper, first, single-user precoding techniques in case of various CSI are study, and their simulation and performance are compared. Then, as the channel variability, the estimation error of the receive channel and the feedback delay, it is difficult to obtain perfect channel information, the limited feedback is analyzed Through simulation.In the paper, multi-user precoding is studied. First, some basic linear precoding techniques are simulated and compared. Then, for the problem of the total channel interference cancellation, BD algorithm is analyzed and verified by simulation that the CCI can be cancelled. In this paper, the combination of BD and MMSE algorithm presents a multi-user joint transceiver design, better use of their advantages, and simulation verification.Finally, a general summary of the full text is done, and clearly the work of the next step to be studied.