Implementation Of Digital Multi-beam Anti-jamming GNSS Processor System

Global Navigation Satellite System not only provides the civil service for Ocean Rescue,Land Surveying and Mapping,Disaster Survey,Personnel and vehicle navigation positioning,ect.But also provides high precise time information and navigation service for military operation,force and soldiers,and became something indispensable in modern war(.The network of GPS satellites provides precise location information everyplace in the world. GPS is particularly vulnerable to jamming, because the receivers are very sensitive, they have to receive the extremely weak signal from orbiting satellites.)Owing to the weak signal of GNSS that arriving at the earth surface,easily be interfered in the complex electromagnetic surroundings,it is very significant to study the GNSS receivers under jamming environments.Firstly,this paper introduces the basic concept of GNSS,and summarize ways and means of the interference and anti-jamming. Secondly,the paper has analyzed technology of GNSS anti-jamming based on adaptive array processing. Thirdly,by analysis of anti-jamming technology and the status of anti-jamming device,the paper provides method of designing anti-jamming GNSS receiver. Finally,the paper provide the testing result and the testing method of the every module.We can see that the system of GNSS anti-jamming can satisfy the need of design.The method of anti-jamming based on adaptive array always has two form,adaptive nulling liner and adaptive beam-forming. Adaptive beam-forming not only eliminate the interference but also form high gain to orientation of GNSS signal.The design of GNSS anti-jamming device apply the mode of mutil-beamformer,and form at least four beams which point to GNSS star, moreover,The device can finish estimating orientation of the interference signal.The design of hardware based on the conception of modularization and Software Radio.and the Implementation of the primary function complete by FPGA. Data transfer between mutil-module depend on LVDS. The module can communicate by high speed,And the capability of system can improve enormously.