Analysis Of Interference Power Threshold Based On Lock-lose Of Receiver And Study On Anti-jamming Of Array GPS

With the application of GPS in modern military gradually expanded,the research on the performance of GPS receiver and the anti-jamming technology in a complex interference environment is increasingly urgent. GPS receiver is divided into CA code and P code,while our country mainly use the weak anti-jamming CA code receiver at present.So GPS jamming and anti-jamming has become the research center for scholars.Firstly, according to the acquisition tracking and demodulation principle of GPS receiver,the article simulate the software GPS receiver. The article proposes that using the interference power threshold which makes GPS receiver lose lock to determine the jamming effectiveness. Analyze the effectiveness to GPS receiver from broadband,narrowband,pulse and deception jamming through simulation experiments. Find that when the power of GPS signal is constant,the least interference power to make GPS reciever lose lock is broadband jamming, then the deception, pulse and narrowband jamming.Then take 4 element Y array GPS signal as an example, the article simulates and finds the anti-jamming capability of MVDR,power inversion and MMSE anti-jamming algorithm. The experiment concludes that the best anti-jamming capability is from power inversion algorithm,second is from MVDR algorithm, the worst is from MMSE algorithm. In view of the MVDR algorithm,the article simulates and researches the anti-jamming performance of the algorithm under different interference and finds that the best anti-jamming effect for MVDR algorithm is under pulse jamming, the second is under deception jamming, then under narrowband jamming, the worst is under broadband jamming. At the same time,considering the three algorithm above,aiming at the interference noise ratio and interference source number may affect the anti-jamming ability of GPS receiver,the article do the simulation analysis and verification for this. The simulation results show that with the increase of interference noise ratio, interference from a part of channel is not adaptively set to zero well and the anti-jamming algorithm performance decreases, proving that the influence of interference noise ratio on anti-jamming ability of receiver exists,and the larger the interference noise ratio is, the greater the influence is. Reduce the number of interference source,the path which can not adaptively set to zero recovers.proving that the number of interference source has influence on the anti-jamming ability of the receiver.At last according to the problem which the failure of main channel for multi-channel GPS receiver will seriously affect the receiver anti-jamming capability, the article presents the compensation to main channel after the channel amplitude and phase correction,and proves the correctness of the plan.