Research On OFDM Wireless Communication Technology Based On AD9361

How to implement the coexistence of multiple systems is an important topic in the field of wireless communication.Software-defined Radio is one of the solutions,which has been frequently proposed in recent years.Due to its small size,low bandwidth,and low cost,the AD9361 is widely favored in the software radio field.At the same time,the XILINX ZYNQ7000 series SOC has been recognized in the industry due to the popularity of the ARM/DSP+FPGA concept in the baseband processing field.Therefore,the AD9361+SOC is a reasonable solution for the current software-defined radio.Orthogonal Frequency Division Multiplexing(OFDM)technology is one of the most widely used technologies in the field of communication technology in recent years,including the popular LTE technology and a lot of future communication technologies.The OFDM technology performs data transmission through mutually orthogonal subcarriers,and therefore has the characteristics of high spectrum utilization and anti-multipath,and is especially suitable for a communication mode of burst transmission.Based on the above considerations,this thesis develops an OFDM wireless communication board based on AD9361,designs the program of OFDM modulation and demodulation,and realizes the joint adjustment of OFDM modulation and demodulation on the board.The specific work is as follows:Designing and implementing the module circuit of the terminal board of the wireless communication system based on AD9361,including RF chip peripheral circuit,RF front-end circuit,baseband processing unit,interface circuit,clock circuit and power supply circuit.Designing and implementing the AD9361 configuration procedure and OFDM modulator and demodulator procedures,including configuration of the AD9361 register,SPI interface timing,digital data interface timing,OFDM training sequence,16-QAM,DFT IP core usage,and frame synchronization,Carrier synchronization,symbol synchronization.Finally,testing and analyzing the overall functions and indicators on the hardware board of the AD9361-based OFDM wireless communication system,and doing the OFDM communication test and analysis on the board.The test results show that the AD9361-based OFDM wireless communication system developed by this project,whose transmitter can transmit signals whose frequency from 70MHz to 6GHz.When the local oscillator is 2290MHz,the difference value of mirror frequency after single-carrier mixing and transmission frequency is about 40dB.Meanwhile,under the condition that the sampling rate of the data is set to 15.36 MHz,the bandwidth of the OFDM spectrum is 30.72 MHz,and the subcarrier interval is about 240 kHz;the receiver AGC can stabilize the average power near-5 dBFS.System index meet the requirements of the program design.Therefore,this system can well integrate not only RF circuits with digital circuits but also hardware and software,and is compatible with a variety of communication systems and communication standards.