Research Of Precoding Technology In Comp Based On LTE-A System

CoMP (Coordinated Multi-Point) is one of the key technologies in LTE-A system. CoMP transports data to users combining antennas of multiple cells, improves throughput capacity and spectral efficiency in the cell edge, and enhances support for the edge user. Pre-coding as an important module in LTE physical layer, can eliminate the interference among users or data streams, enhance the performance of the system. It has theoretical and research value combined with CoMP.The thesis studies the combination of pre-coding with CoMP technology in LTE-A physical layer. Firstly, this thesis introduces the main features of LTE-A system, followed CoMP technology for pre-coding technology in depth analysis of the traditional pre-coding algorithm, such as:ZF, MMSE, BD, SLR, THP, etc. In this thesis, we design pre-coding scheme, compare the performance differences between the various pre-coding algorithms. Secondly, we optimize some of algorithms, combining the BD algorithm with the MMSE criterion, combining SLNR algorithm with ZF criterion. We make the simulation in CoMP scenarios of LTE downlink, concluding BER performance and system capacity. Finally, we discuss the THP algorithm for further study. We make the theoretical derivation of the GMD-THP pre-coding, BD-GMD-THP and improved BD-GMD-THP algorithm, compare the advantages and disadvantages of different algorithms. The BER performance of improved algorithm is better than the others in lower SNR environment, improving the reliability of the system.