Reaserch And FPGA Implementation Of Physical Downlink Shared Channel In LTE System

Based on the research of LTE physical layer protocol,this paper mainly studies the processing of LTE Downlink Shared Channel Data,and gives the realization scheme based on FPGA.In this paper,we first introduce the background of TD-LTE and the development of Cellular Mobile Communication,then in the second chapter we mainly describe TD-LTE physical layer related technologies,such as frame structure,resource allocation scheme,TD-Downlink related channel,physical layer communication process and briefly introduced OFDM and MIMO technology.OFDM and MIMO technology is the key technology that LTE can improve the system performance,OFDM technology can improve the spectral efficiency of the system and MIMO technology can provide the channel capacity and reliability.This paper focuses on the LTE physical downlink shared channel processing,the physical downlink shared channel mainly carries downlink service information and partial paging information,the data processing includes CRC,code block segmentation,turbo coding,rate matching,scrambling,modulation,layer mapping,precoding and other processes,and then intorduce its FPGA implementation scheme.Taking into account the physical downlink shared channel carrying a large amount of data so we provide a data pipeline parallel processing program to reduce its data processing time,leave a lot of time to the upper scheduling algorithms;In the symbol-level processing we propose a pre-mapping algorithm,the idea is to allocate resources before making the symbol-level processing,storage the bit-level data according to a predetermined sub-frame format to avoid storage the symbol-level data,saving the RAM resources of the FPGA chip.At the end of this paper,we introduce the downlink simulation platform of matlab,and describe the specific process of the receiver and the sender,and analyze the the simulation results of absence of business process and business process,which verifies the correctness of the algorithm.