用于卫星导航终端的抗同频干扰电路研究与设计OA

To address the problem of satellite navigation terminal systems being interfered by radar co-frequency signals,this study proposed a design method for anti-co-frequency interference circuits applied to satellite navigation terminals.Utilizing the inherent characteristic differences between linearly polarized waves and circularly polarized waves,a combined circuit consisting of a 90°coupler and a radio frequency(RF)unidirectional circuit was adopted to suppress linearly polarized waves while maintaining the normal reception of circularly polarized satellite navigation signals.A matching network was designed for the dual B1 and B2 frequency bands to solve the technical difficulties of resisting co-frequency interference from linearly polarized radar waves.Measured results showed that the suppression depth of linearly polarized interference waves was less than-5 dB within both frequency bands,among which the suppression depth of linearly polarized interference waves reached-10.3 dB at 1.207 GHz and 1.561 GHz.This study provides an effective solution to the problem of satellite navigation terminals being interfered by co-frequency signals and has significant engineering application value.