Research And Implementation Of Anti-jamming Technology For Satellite Navigation Receiver Based On Array Antenna

The global navigation satellite system(GNSS)provides users with highly accurate positioning information while enabling navigation.However,due to the lack of measurement accuracy,it is still not widely used in aircraft landing.Therefore,differential positioning technology has been introduced into the aircraft landing system.The airport's reference satellite navigation receiver has gradually developed into a ground-based augmentation system(GBAS)to provide nearby aircraft.Navigation and precision approach services.However,the electromagnetic environment of the airport is complex and there are various kinds of interference.During the landing stage of the aircraft,the satellite navigation receiver used in the GBAS system is vulnerable to various electromagnetic interferences and cannot work.It challenges the reliability.The related technologies of navigation receiver anti-interference have been studied and implemented.This thesis revolves around the problem of anti-interference of satellite navigation receivers in GBAS system by using array antennas.In the algorithm selection,two kinds of algorithms commonly used in satellite navigation receivers are discussed.They are the algorithm of zero-fall formation and beam pointing.Class algorithm.After detailed analysis and simulation of the algorithm and comparison,combined with the development requirements of the anti-jamming satellite navigation receiver in the subject,the anti-interference algorithm based on power inversion is determined as the core of the anti-interference algorithm of the receiver array antenna.In the implementation of the algorithm,the FPGA implementation process based on the power inversion anti-jamming algorithm is described in detail.The research content of this paper includes:1.Read the relevant literature,understand the basic composition principle of satellite navigation receivers,study how to use array antennas to increase the anti-interference function of traditional satellite navigation receivers,and investigate the current relevant design and research status at home and abroad.2.The existing satellite navigation receiver and array antenna anti-jamming technology are briefly introduced and analyzed.Then,two kinds of anti-interference algorithms widely used in satellite navigation receivers are discussed in detail,respectively.Algorithm and beam pointing algorithm.In the algorithm of null formation algorithm,the algorithm analysis and performance simulation of power inversion algorithm and subspace projection method are carried out.In the beam pointing algorithm,the algorithm analysis and performance simulation of the traditional beamformer and blind beamformer are performed.Combined with the development requirements of anti-interference satellite navigation receivers for array antennas,the anti-jamming performance and implementation complexity of the four algorithms are compared and analyzed in detail.Finally,the power-inversion-based anti-deformation algorithm in the null-forming algorithm is adopted.The interference algorithm is the core of the receiver array antenna anti-interference algorithm.3.On the seven-element anti-jamming receiver board,Verilog programming is used to implement the anti-interference algorithm based on power inversion.The algorithm is disassembled and divided into three basic modules:digital down conversion module,power inverted anti-interference module and digital up-conversion module.The basic working principle and design steps of each module are explained in detail,and then Modelsim is used.The simulation verifies the correctness of the work of each module.And the test environment was actually built,and the anti-jamming performance of the satellite navigation receiver was tested.The test results show that the anti-interference algorithm based on power inversion can additionally increase the dry-noise ratio suppression capability of the receiver by about 45dB in narrow-band interference,and additionally increase the dry-to-noise ratio suppression capability of the receiver by about 35dB in wideband interference.The correctness of the algorithm is verified.