Fog backscattering interference suppression algorithm for FMCW laser fuze based on normalized frequency spectrum threshold

Fog backscattering can cause false alarm for laser fuze. The characteristics of the target echo signal and the fog echo signal of FMCW laser fuze are comparatively analyzed. Based on the frequency domain feature of beat signal in these two cases, a fog backscattering suppression method based on the normalized frequency spectrum threshold of beat signal is proposed. Experimental results from simulated laboratory environment showed that the algorithm can identify the target and the fog interference with the correct rate of 91%. This algorithm provides a new method to suppress the fog backscattering for the frequency modulated continuous wave laser fuze.