Research And Implementation Of Key Technology For LTE-A DL Physical Layer

Recentily, with the rapid development of wireless communication technology and the increasingly improvement of LTE technical standards. Including China, many countries have already enjoied the LTE service. Nowdays, LTE has become a mainstream technology in the field of mobile communications.Meanwhile in order to promote the 5G development in China, researching on key technologies of LTE-A system is very necessary.The paper combines the working experience on 4G basestation in Beijing Northen FiberHome, introduces the framework of LTE-A system、the downlink physical layer and the MIMO and OFDM technology. On the basis of the understanding of the physical layer protocol, paper mainly studies the downlink symbol processing and multiple bandwidth OFDM design. And test the design on the hardware platform.According to the LTE-A request to the system performance, baseband process unit uses FPGA+DSP+PowePC architecture firstly. Then introduce the function division between each chip and how they connect with each other.LTE downlink symbol processing is composed of scrambling module, modulation module, resouce element mapping module and OFDM module.Through Matlab simulation platform generate test data for each module to simulate;During the design, taking the advantage of parallel process in FPGA, scrambling and resources mapping module desing in a resources saving but whit high throughout method. Associating with modern EDA tools and Xilinx IP core, realizes multiple bandwidth OFDM system.This provides the reference to other communications system design.