Research On GPS Anti-jamming Adaptive Antenna Algorithm

GPS (global positioning system) is the most advanced and most widely-used satellite-based radio navigational and positioning system. However, because of some limits of GPS itself, weak anti-jamming performance is always a urgent problem of the system. Even some weak interferences can lead the GPS receiver unable to work. Thus, GPS anti-jamming has been a hot topic in both academic and industry research areas all around the world. Within the research achievements of this topic, utilizing adaptive antenna to mitigate the impact of interferences has been considered a very effective method.Based on elaborating the system structure of GPS, GPS signal characteristics, and the principle of adaptive antenna, we have compared and analyzed two GPS anti-jamming adaptive algorithms, which are the power inversion algorithm, and linear constrained RLS algorithm. With simulation on Matlab, two algorithms’ output SINR, convergence performance and the antenna pattern of the adaptive array, has been fully analyzed under interferences’ different arriving direction, number and power. Moreover, the performance of two algorithms in many aspects have been compared, and the selection advice in different application circumstances has been given as well.In the following, to study the improvement that the algorithm has brought to the GPS receiving system, we introduced the realization of GPS link simulation based on anti-jamming adaptive antenna algorithm, given the simulated GPS signal acquisition results in different conditions. And based on the simulation results, the effectiveness of the algorithm has been analyzed.