Abstract: Radar-while-drilling is playing an important role in ensuring drilling safety. Linear frequency modulation continuous wave (LFMCW) signal is usually used by radar-while-drilling. The paper analyzes working principle and realization method of LFMCW radar-while-drilling theoretically, and then the information extraction of target echoes of LFMCW radar-while-drilling is achieved by using fast Fourier transform (FFT) technique. The simulation result verifies the correctness of theoretical analysis and feasibility of implementation method.