Nonlinear FMCW Laser Ranging System Based on Sinusoidal Frequency Modulation

This study presents the design of a nonlinear Frequency Modulated Continuous Wave (FMCW) laser ranging system. Contrasting the commonly used triangular wave linear modulation, this study employs sinusoidal wave modulation. The frequency information of the original sinusoidal modulation signal is calculated using the IQ demodulation method. Following the fitting of the measured interference signal at equal frequency intervals, the corresponding distance information is obtained using Fast Fourier Transform (FFT). The principle of this method is thoroughly analyzed and derived, with its correctness subsequently verified through experimental validation.