GNSS Imaging: A Case Study of Tree Detection Based on Beidou Geo Satellites

Abstract

Abstract-Curved trajectories of traditional navigation satellites limit their performance in bistatic radar imaging system. Instead of using common Inclined Geosynchronous Orbit (IGSO)/Medium Earth Orbit (MEO) satellites in motion, a new global navigation satellite system (GNSS) imaging system based on Beidou geo synchronous orbit (GEO) satellites is presented to deal with this problem. The most prominent feature of GEO satellites is that they are still relative to the earth. This work includes three parts. First, a reasonable parallel assumption is provided to simplify the geometric topology of the imaging system, and the relevant path delay formula is deduced. Second, the principle of imaging based on multiple GEO satellites is proposed, and the simulation result is presented. Third, the entire signal processing, which uses a multi-correlator, is designed to improve the range resolution. Two imaging experiments targeting at the trees are described and conducted in Wuhan University to verify the imaging system. The first experiment is targeted at isolated trees, and the second experiment is focused on groves along the road. Conclusion can be obtained: the imaging result is highly consistent with the imaging area, which validates the feasibility of the method and confirms the potential use of GNSS imaging system in forest monitoring.

SNR Improvement for Maneuvering Ship Using Weak Echo Under the Condition of Beidou GEO Satellites

“…Because the periodic offset of the azimuth angles is similar to that of the elevation angles, we ignore the information about the azimuth angles. The offset of azimuth angle can be seen in [27].…”

SNR Enhancement of Back Scattering Signals for Bistatic Radar Based on BeiDou GEO Satellites

“…When the radio signal transmitted from the navigation satellite impinges on the target, it is reflected and contains the target information, then a satellite-based, aircraft-based, or ground-based receiver is employed to capture this signal and retrieve the physical parameters such as vegetation optical depth, soil moisture, sea ice surface, and ocean surface wind speed [1,2]. Especially, when the receiver is installed at a fixed position on the ground, the receiver can be used for target imaging [3][4][5][6], maritime target detection [7,8], and surface deformation monitoring [9,10]. GNSS signals are particularly attractive given their advantages of multiple frequencies, low cost, and global coverage.…”