A Research On Radio Direction Finding Algorithms Based On Software Defined Radio

In recent years,with the continuous development of software defined radio technology,more and more traditional radio technology began to combine with software defined radio platform.Because the radio monitoring and direction finding system based on software defined radio can solve the problem of limited monitoring range in traditional radio services,more and more researchers are studying the direction finding system based on software defined radio.This system adopts a combination of hardware and software,which reduces the size of the system while controlling the cost.It is more convenient to compile the algorithm module of the software part on the basis of the general hardware,which is also the main direction of the development of the direction finding system at present.In view of the above situation,this paper designs an algorithm testing system based on software defined radio's software platform--GNURadio.At the same time,the corresponding direction finding algorithms are deeply studied.Firstly,based on the principle of spatial spectrum direction finding algorithm,combined with the actual project requirements,an improved MUSIC algorithm with better performance under small snapshot number and low signal-to-noise ratio is designed.Considering the large computational complexity of the algorithm,a joint improved algorithm combined with interferometer direction finding algorithm is proposed.Combined with the technical indicators,the performance of the improved MUSIC algorithm is analyzed by using the simulation software MATLAB,and the time consumed by the proposed joint improved algorithm is analyzed.Finally,the advantages of the proposed algorithm are verified.Then,considering the limitation of signal processing speed of current hardwares,the compressed sensing direction finding algorithm is studied in this paper.Among them,this paper focuses on the OMP direction finding algorithm and L1-SVD direction finding algorithm.The above two algorithms are simulated and analyzed by MATLAB.In addition,the above two algorithms are compared with the improved MUSIC algorithm,and the related performance is analyzed.Then the corresponding conclusions are drawn.Finally,this paper used GNURadio,a software platform of software defined radio,to build a simulation test platform for direction finding algorithm,which can load the previous algorithms to test the previous algorithms.In this software platform,the corresponding algorithm can be loaded to get the corresponding result graph,and the influence factors of the algorithm can be analyzed by the results.The algorithms studied in this paper can be loaded into the radio direction finding system based on software defined radio.It is mainly used in the scene of radio monitoring and direction measurement commonly used by departments such as radio committees,focusing on the civil field.Of course,because of the flexibility of the system,the corresponding algorithm can be changed at any time to be used in practice to improve the accuracy,portability and real-time performance in the actual direction finding process.