A Strong Interference Suppressor for Satellite Signals in GNSS Receivers

摘要

In this paper, we discuss a method to protect satellite signals from strong time-varying interferers. Time-domain, transform-domain, and space-domain algorithms have been widely used for interference suppression. However, when used under high dynamic conditions, these methods cause serious suppression of satellite signals in the GPS receivers along with inhibiting interferers. To address this problem, we optimize the satellite and interference steering vectors using a multi-star forming approach to distinguish satellite signals and strong interferers. In order to detect time-varying interferers, we further introduce a novel hidden Markov model (HMM), and power inversion (PI) and Multi-star interference suppressed (Multi-PI) model anti-interference synthesis scheme.A bank of HMM filters are operated to track the on-off interferers in the frequency domain, and decide if an anti-interference algorithm needs to be used. After HMM, the Multi-PI algorithm is implemented to inhibit broadband interferers. The experimental results show that our novel scheme adapts quickly when tracking time-varying interferers and protects GPS signals from losses.