Bistatic Sensing with Reflected GPS Signals Observed With a Digital Beam-Steered Antenna Array

Reflected GPS signals have applications for remote sensing including: earth mapping, ocean surface mapping, terrain modeling and digital mapping through application of bistatic signal processing techniques. Previous research in such uses of reflected GPS has been limited by the weak signal power of these bistatic GPS signal returns. This paper describes the design of a Digital Beam-Steered antenna array, which is used to increase the Signal/Noise ratio of the GPS bistatic signal returns to allow sensing of both specular and diffuse GPS signals. Flight test data is presented to demonstrate the performance improvements possible using Digital-BeamSteering for improved GPS bistatic signal processing and remote sensing.