Algorithm development for multistatic GNSS radar technology

Abstract: Bistatic GNSS radar has received increased attention in recent years within both the radar and the GNSS communities. Its major advantages are that it has complete earth coverage and that more information is available due to the geometric diversity of the transmitters. Also, the receiver in a multistatic radar system does not have to transmit a signal which enables development of low power and low cost equipment. This thesis describes contributions made to multistatic GNSS radar algorithms for surface characterization and object detection. By analyzing the strength and shape of the reflected signal's waveform properties of the surface and the height above ground can be determined. In addition to this primary reflection, transient secondary reflections can be found in bistatic GNSS radar data. These are due to reflections in buildings and other structures only when the geometry between the GNSS satellite, measurement platform, and the reflecting body is correct. An algorithm to detect these reflections and determine the location of the reflecting object has been developed and tested experimentally. Previously, significant effort has been put into develop the synthetic aperture radar (SAR) theory to include the bistatic situation. These algorithms are here developed further into a more generic multistatic GNSS SAR system for surface characterization. This is done by using range and doppler processing techniques on signals transmitted by multiple satellites to determine the angular dependence of the surface reflectivity. The developed algorithm have also been tested experimentally.