Research On Precoding Algorithm In CoMP For LTE

LTE system introduced CoMP technology to improve the performance of users locaded in the cell edge and meet the requirements spectrum efficiency in the cell edge.CoMP technology can achieve that channel informations and data informations are shared between multiple cells, in order to optimize the performance of cell-edge users and the whole system.And the main way to achieve the improvement of system performance for the CoMP technology is precoding technique.The basic idea of precoding is that precoding matrix is computed by a state of channel information gained in the transmitting terminal and uses the matrix to preprocess the transmitting signal, so as to achieve the purpose of reducing the system error rate and improving system capacity.The precoding technique of the joint treatment for CoMP technology is mainly researched in this paper.First of all, the technology of CoMP is analyzed detailly,such as the classification of the CoMP technology,the transmission model and the application scenarios.Then,the basic ideas of precoding and the species of precoding also is given in the paper,the most important point is paid on four kinds of precoding algorithm under the way of linear precoding,namely the ZF,MMSE,SLNR and BD precoding,on the basis of theoretical analysis,four precoding algorithm is simulated by Matlab with error rate and systerm capacity as its performance indicators.Finally,according to the conclusion of analysis,two kinds of improved algorithm is put forward,namely the BD-MMSE and the ZF-SLNR precoding algorithm, and the original algorithms and the improved algorithms are simulated.Final results shows that the improved algorithm has better performance than the original algorithm. the improved algorithm achieves that error rate is reduced and system capacity is improved.