A Research On Radio Frequency System With Key Technologies Of LTE-FDD Base Station Based On AD9375

The fourth generation mobile communication technology is another evolution of wireless communication technology after the third generation mobile communication.According to duplex mode,LTE system can be divided into FDD-LTE and TD-LTE.The development of LTE puts forward higher requirements for radio frequency(RF)system.With the evolution of mobile communication technology and the popularization of commercialization,the research of RF system based on LTE base station is also developing continuously.This paper focuses on AD9375 RF transceiver chip of ADI company to study FDD-LTE RF system.The main work of this paper is summarized as follows:1.Design the power supply module around AD9375 RF system,providing the corresponding power supply voltage for each module of the whole radio frequency system,and ensuring the normal operation of the whole system.2.Design clock management module around AD9375 RF system,cooperating with JESD204 B serial high-speed transmission interface to provide the corresponding reference clock and synchronous clock for each module of the whole RF system,and complete the synchronous operation of data transmission.3.Design RF transceiver module around AD9375 RF system.The signal from the AD9375 chip is amplified,filtered and selected to achieve the functions required by the base station system.4.Aiming at the situation that ADI company no longer provides register map about products after AD937 x series,the embedded system is constructed with Xilinx development board to control the overall configuration of custom RF board.5.A broadband high-efficiency power amplifier based on the third generation semiconductor material GaN is designed with a new design idea combining Simplified Real Frequency Technique(SRFT)and Class-F technology for the communication distance and working frequency band of AD9375 RF System.This paper designs and implements a FDD-LTE RF system based on AD9375.The system includes a complete radio frequency transceiver function.It can achieve up to 12.5 Gbps transmission rate in the process of communication with the baseband.It has the characteristics of a variety of working modes and application scenarios.The power added efficiency(PAE)of the broadband power amplifier is more than 60% in the band range of 1.6 GHz-2.8 GHz,and the gain is between 10.7 dB-12.7 dB.The relative bandwidth of the power amplifier reaches 54.5%.The RF system is connected with Xilinx's development board through FMC connector,which is of great significance to the research and development of RF applications.