The Design And Implementation Of CoMp Wireless Communication System

Compared to the 3G technology based on CDMA, the modern wireless communication system based on MIMO and OFDM technology has higher data transmission capacity and spectrum utilization. However, orthogonal multiple access in LTE systems leads to serious inter-cell interference, and the traditional inter-cell interference coordination technology cannot effectively improve cell-edge user performance. In order to satisfy the requirement of IMT-Advanced system, Coordinated Multi-Point Transmission(CoMP) technique is introduced in LTE-Advanced system, which can provide data services for a single or multiple users through the cooperation of multiple transmission points in different position. And this technology shall eliminate or suppress inter-cell interference and enhance the cell coverage, which can benefit the cell-edge throughout and overall system capacity. In this thesis, we build up CoMP wireless communication system through hardware implementation to complete the functional verification of CoMP technology. The main work of this thesis includes the following three parts:(1) Firstly the research background and the current industry situation are presented. The key technology of CoMP is summarized, and the transmission mode including Joint Processing and Beamforming are focused on. The author starts from the precoding technology in the physical layer, and design the suitable scheme for the hardware implementation through simulation and analysis of different precoding algorithm.(2) Subsequently, in view of the hardware implementation of precoding algorithm,matrix operations are studied. And the author detail matrix cholesky decomposition, QR decomposition and matrix inversion based on systolic array and the main eigenvector solving based on power method. Then hardware implementation of each module is designed which provide solutions of the key baseband processing in CoMP wireless communication system.(3) At last the system design scheme is demonstrated for the application of scenario of two base station and two user terminals. And the downlink simulation is built up to provide theoretical support for the realization of the system. The hardware implementation of several baseband processing modules including turbo decoder, MIMO equalizer and modulator-demodulator is completed, mapping in the Network on Chip platform based on multiple FPGAs. And system board debugging and uplink and downlink wireless test is completed. Test results show that this system can effectively improve cell-edge user performance.