Detection, Characterization, and Localization of Interference Signals in Wideband GNSS Environments: the GIMAD System

We present in this paper a design for a monitor-ization station that will be part of a network of receivers in charge of providing a service for detection, characterization, and localization of interfering signals in safety critical GNSS environments. The purpose is to cover a wideband frequency range from 800 MHz to 1900 MHz with a power level mask taken from EGNOS and DFMC GBAS requirements. The proposed design combines two four-element arrays with two USRP units for collecting signals within the desired SNR margins. A comparative simulation study has been done to evaluate different techniques for interference detection, characterization, and estimation of its angle of arrival. The results show that a combination of power and kurtosis monitorization, both in temporal and frequency do-mains, is a proper solution to detect different types of interfering signals. In order to assure the best signal characterization, the use of the three selected techniques serves to overcome their respective limitations. For angle of arrival estimation, the fact of working in a suboptimal array configuration provides more robustness against outliers for certain geometries.