Abstract: Airborne microwave imaging Radar for remote sensing plays an important role in earth observation, especially in the application to cities. Linear frequency modulation continuous wave (LFMCW) radar with the feature of high reliability and compactness is suitable for multiple applications in airborne radar. The advantages and application environment of LFMCW SAR is analyzed in this paper, and the methods of signal design and signal processing in LFMCW SAR are studied. A point target simulation result is given that shows LFMCW SAR has good space resolution.