Concepts, Development, and Validation of Multiantenna GNSS Receivers for Resilient Navigation

Abstract

Array processing proved itself in the last decades as a powerful approach to suppress harmful radio frequency interference. However, the interference mitigation in the spatial domain can also lead to the attenuation and loss of the desired Global Navigation Satellite System (GNSS) signals that are not sufficiently separated by their directions of arrival from the interfering signals. In order to overcome this effect, this paper proposes an approach to combine array processing and vector tracking in a single receiver. Formerly, the vector tracking loops have been shown to deliver superior performance in scenarios with blocked line-of-sight signals due to aiding of the affected signals during the outage. Since vector tracking loops are susceptible to faked GNSS signals, the proposed receiver architecture also includes a spoofing detection based on the direction-of-arrival estimation. The paper presents the technical concept and details about the realization of the array-based receiver that was developed at the German Aerospace Center (DLR). The techniques used to mitigate brute-force radio frequency interference and to detect spoofing signals are described. Experimental results obtained with these techniques in field are discussed.