In response to the widespread application of Doppler maps in radar signal processing,but facing the issue of low accuracy in complex situations,this paper proposes a Canny edge detection-based spatial-frequency combined image enhancement algorithm.This method first utilizes an existing dataset to perform spatial-frequency combined processing on the original images using histogram equalization and homomorphic filtering.Then,it applies the Canny edge detection oper-ation aiming to enhance spectral information.Finally,the KNN(K-Nearest Neighbors)algorithm is employed for the recogni-tion and classification of the spectral maps.The experimental results indicate that the proposed algorithm can effectively im-prove the recognition accuracy of six types of actions,such as jumping and running,to 94%.This validates the feasibility of the proposed method for processing spectral maps and performing classification.