Low Scattering Design of Satellite Navigation Antennas Under Grazing Incidence Conditions

This paper presents a low scattering satellite navigation antenna guided by Antenna Scattering Theory based on Characteristic Modes (AST-CMs). The main scattering modes contributing to high scattering are analyzed using AST-CMs. Fan-shaped slots around the antenna patch are added to reduce the Modal Wave Coefficient (MWC) of the main scattering mode, achieving a low-scattering design under grazing incidence conditions. Simulation and experiments validate the effectiveness, showing a minor gain reduction of 0.15dB compared to the reference antenna. The design achieves a scattering reduction of 1-3GHz under grazing incidence conditions, with a maximum reduction of about 20dB.