Research On Radio Surveillance &direction-finding And Localization Technology

Radio monitoring refers to the activities which use advanced equipment and technology to detect, search, intercept, recognize and monitor the wireless signal, and to obtain its technical parameters, work characteristics and the position of radiation and other technical information. With the rapid development of wireless technology, radio interference happens frequently, making the radio monitoring tasks increasingly burdensome. Most of the radio monitoring networks which used widespread currently are composed of several large monitoring stations, the construction cost is high, volume is huge. Vehicle-mounted miniature radio monitoring systems become the powerful supplement of large radio monitoring system due to the advantages of low cost, strong maneuverability and extensive use-area.This thesis takes the radio monitoring technology as the topic and mainly studies vehicle-mounted miniature radio monitoring platform, the processing and direction finding of radio monitoring signal, DOA positioning, etc. Based on the above discussion,the main research content of this thesis is divided into the following four parts.First of all, it gives a general introduction of the hardware structure and the main index of the radio monitoring system, based on which the following researches are carried: the SG simulation and FPGA implementation of QPSK signal timing and carrier recovery, including Gardner algorithm and DD algorithm.Secondly, it researches the algorithm of correlation interferometer and dimension reduction optimization, proposes the phase accumulation algorithm to improve DF errors in low SNR. After that, it discusses the effect of error factors to the DF accuracy through simulation, including the antenna array aperture, SNR, signal frequency, etc.According to the characteristics of FPGA, it optimizes the cost function by Archimedes correlation function, improves the computing speed and reduces resource consumption of FPGA. At last it implements the dual channel correlation interferometer system based on FPGA platform.Lastly, it studies the DOA location technology and analyzes the influence of positioning accuracy by the DF errors, base station positioning accuracy and the length of baselines through the simulation. And it makes systematic study and comparison on the two dimension optimum intersection angle of cross positioning problem, then presents particle swarm optimization(PSO) algorithm to improve 3D altitude locationaccuracy through suitable Fitness function. Lastly, it implements the DOA location and PSO algorithm in FPGA.This thesis concentrates on the vehicle-mounted miniature radio monitoring technology, and it covers the researches of basic algorithm, miniaturization, integration of project implementation, DOA location and DF algorithm innovation, etc. Optimizes the original IF processing structure of the FPGA + DSP + PXI with single slice FPGA system, and implements the signal processing, DF, DOA location and PSO algorithm,interface between lower computer and upper computer. This research improves the system integration and miniaturization, reduces the cost of the vehicle-mounted miniature radio monitoring system.