Civil GPS Jammer Geolocation from a UAV Equipped with a Received Signal Strength Indicator Sensor

Abstract

This paper aims to develop a GPS Jammer localisation scheme using a single UAV platform fitted with a low cost sensor. This is primarily achieved with power measurements from a GPS monopole antenna placed on the UAV and with a Differential Received Signal Strength (DRSS) geolocation approach. In order to select which type of estimation filter would fit well with the gelocation problem considered, a few stochastic filters and batch
processing methods are investigated. As a simple Extended Kalman Filter (EKF) provides comparable performance against other, potentially more complex, filters, this paper considers the EKF as the baseline filter. Since the performance of the EKF is degraded under the target’s highly anisotropic radiation patterns, this paper proposes an innovative, but simple, approach which uses a bank of EKF to cope with the anisotropic radiation patterns. The guidance scheme consists of a straight & level area flyby followed by an orbital adaptation phase using a Lyapunov Vector Field Guidance (LVFG) that refines the position estimation and brings the UAV onto a stand-off orbit around the target. The performance of the proposed scheme is verified via numerical examples.