Abstract:The traditional frequency-domain anti-interference technology of satellite navigation signals is processed in the frequency domain of the received signal, and the spectrum of the interference signal is suppressed to achieve anti-interference. This method suppresses the interference while suppressing part of the signal, resulting in the loss of signal energy. Aiming at this problem, a frequency domain anti-interference algorithm using the spectrum symmetry of satellite navigation signals is proposed. This method utilizes the spectrum redundancy of satellite navigation signals and uses it in the process of interference spectrum suppression. A complete signal spectrum can be obtained by recovering the symmetrical undisturbed lines. The simulation data of Beidou B3 frequency point code shows that when the spectrum of the interference signal appears on one side of the center frequency, the proposed method is not sensitive to the bandwidth of the interference signal, even if the spectrum of the interference signal accounts for half of the signal spectrum, the energy of the output signal remains stable; the loss of signal energy is reduced during the interference line rejection compared to that in conventional methods.Simulation experiments show that in typical scenarios, the proposed method can improve the carrier-to-noise ratio by about 1 dB compared with the traditional zero-setting method.