Anti-Jamming Algorithm Research And Implementation Based On Polarization Space-Frequency Adaptive Processing

The global satellite navigation plays an increasingly important role in the field of military and civilian,especially in military field,it is of great significant.In recent years,with the rapid development of China's Beidou satellite navigation system,and in the face of increasingly complex electromagnetic environment of space,anti-jamming technology of the satellite navigation receiver,which with the characteristic of miniaturization and high performance,has been widely research and application.Based on polarization sensitive array signal processing theory,this dissertation focuses on the anti-jamming technology based on the polarization space-frequency domain,and optimizes the robust performance of the algorithm,which can effectively enhance the anti-jamming performance of satellite navigation receiver.The major work of this dissertation includes:(1)Polarization-space beamforming is introduced,and its inherent characteristics are analyzed by establishing a mathematical model.In addition,the performance of the polarization sensitive array is compared with the performance of the traditional scalar array by a large of simulation analyzes.So these features are proved that polarization-space beampattern has no grating-lobes in sparsely spaced array and can effectively restrain the jamming signal,which has the same DOA parameters and the different polarization parameters with the desired signal.(2)Aiming at the orthogonality between channels of the polarization sensitive array,polarization-space-frequency adaptive processing based on quaternion(QPSFAP)is proposed.And it is proved through the simulation analysis that compared with the polarization-spacefrequency adaptive processing based on longer steering vector,QPSFAP has better robust performance.(3)Probability constraints are imposed for designing a robust QPSFAP algorithm against random steering vector mismatch.In order to solve the problem of the probability constraints,a Bernstein-type inequality for stochastic is employed to transform the probability constraints to a convex optimization problem which can be solved.This method effectively improves the robust performance of the QPSFAP algorithm with random steering vector mismatch.(4)A robust QPSFAP algorithm based on generalized sidelobe cancellation(GSC)and the broadening technology of covariance matrix is proposed against the jamming with rapid changes in position.As a result,the complexity of the QPSFAP algorithm is reduced and the beampattern is effectively widened at the jamming null position.And then,the robust performance of the QPSFAP algorithm against the jamming with rapid changed in position is enhanced.(5)The QPSFAP algorithm,which combined with the robustness optimization strategy,is applied to the satellite navigation anti-jamming system.And the system architecture,combined with the actual engineering project,is established.Additionally,the design of FPGA software module and the key optimization strategy are elaborated.In order to further prove the superiority and the practicality of the technology,the measured results of the system are analyzed in detail.