Abstract: In order to extract the characteristic information of the target echo signal and improve the simulation accuracy of the echo signal, a digital simulation method was adopted to record the echo data in the ground verification test. Quadric surface element was used as the basic element of geometric modeling to establish the target geometric model. Based on the material of the target surface and the measured data of bidirectional reflectnace distrbution function (BRDF), five-parameter modeling was carried out for samples of different wavelength from different angles by combining genetic optimization algorithm. The amplitude of point return wave of target under different environment was verified by the method of region joint discrimination of echo envelope rising rate. The results show that the deviation between the voltage in the cloud environment and the ideal environment is about 65.3%, the enveloped trend satisfies the criterion of target recognition, and the anti-interference is realized in the cloud environment, which can modify and improve the simulation model of target echo signal in the cloud and smoke environment and improve the simulation accuracy.