Key Techniques Of Joint Processing In LTE-Advanced Comp System

Coordinated Multi-Point (CoMP) is one of the key technologies in LTE-A (Long Term Evolution-Advanced) system. It solved the problem that users in the edge of the cell are with poor quality of service and low throughput. On one hand, we use the pre-coding technology to suppress the interference between cells and users in CoMP systems. On the other hand, the number of users that can be served in the base station is limited at one time. So the performance of user scheduling scheme will directly affect the capacity of the CoMP system. Thus, the research of CoMP pre-coding system and user scheduling technology is of great importance.The thesis analyzes the pre-coding technology in the CoMP transmission system, which include the advantages and disadvantages of the MMSE (Minimum Mean Square Error) pre-coding and SLNR (Signal to Leakage and Noise Ratio) pre-coding. As we know, the SLNR algorithm cannot eliminate the interference from itself. The thesis has combined the SLNR algorithm and the ZF (Zero Forcing) criterion. Meanwhile, the author has done some simulation of it. The result showed that the BER (Bit Error Rate) and the system capacity will be greatly improved in the combination of the SLNR algorithm and the ZF criterion. At the same time, the thesis has compared the simulation result of the RR (Round Robin) the Max C/I (Carrier to Interference ratio), the PF (Proportional Fair) scheduling and the integrated scheduling algorithm in the CoMP system, which shows that the integrated scheduling algorithm can fully consider the inter-cell interference. To a certain extent, the average user spectral efficiency in the cell edge and the cell average spectral efficiency are improved in terms of the PF scheduling algorithm.