Application Study Of Interference Suppression For Adaptive Antenna Array In GNSS Receiver

Global Positioning System use satellite navigation signal for navigation and positioning.Global navigation satellite systems(GNSS)have been applied in many fields.Because of its inherent weaknesses,the GNSS is vulnerable to interfere by various radio signals.Anti-jamming technology has become one of the essential functions of the satellite navigation receiver,because of increasingly complex electromagnetic environment of space and the increasing number of hostile anthropogenic interference.Satellite navigation receiver adaptive antenna system can suppress interference effectively and improve signal-to-interference ratio of the received signal simultaneously in the airspace,which has become a research focus at home and abroad.The work of this paper is directed to the airspace interference related knowledge for research and innovation.Firstly,domestic and foreign satellite navigation terminal about interference and anti-jamming is summarized,analyzing the characteristics of the existing anti-jamming technology.Moreover,this paper introduces the structure of GPS signal,and analyzes the characteristics of weak GPS signals,which has various types of serious interference.According to the characteristics of the weak GPS signal,the math model has been established.The simulated digital IF signal provides the conditions for the research of acquisition algorithm.Secondly,the paper focuses on the airspace anti-interference principles,classifications,signal model and Adaptive forming Algorithm,the core technology analysis.The paper discusses several criteria of the adaptive forming algorithm,introducing two kinds of typical adaptive algorithms RLS and LMS,the MATLAB simulation results show the limitations of RLS and LMS adaptive algorithm in interference in the application?Adaptive antenna array,which mitigates interference signals by the spatial adaptive processing(SAP),has been widely used for interference suppression in GNSS receiver.As an impacetful filtering tool in spatial domain,adaptive antenna arrays have played a key role in interference suppression for GNSS receivers.Moreover,the space-time adaptive processing(STAP)is applied to improve the performance of anti –jamming of the antenna array.This paper analyzes the working principles of SAP and STAP,and then shows the anti –jamming performance of SAP and STAP by simulation.Ii is proved that STAP has a better performance in the case of multiple jamming signals.