Extracting the novel signal parameters is an effective means to solve the sorting problems of complex radar emitter signals. The features of the slice of ambiguity function main ridge are one of the most feasible parameters among various characteristics. To search the slice of ambiguity function main ridge of signal more quickly, a smart search algorithm based on superiority inheritance was constructed and statistical hypothesis testing theory was used to analyze and test the obtained data. The results of simulation show that, the proposed method can reduce the search time to 28.6% that of original method while obtaining the right slice with higher success rate and higher accuracy.