Research And Implementation On A Kind Of Modulation Recognition Algorithm For Communication Signals

With the rapid development of communication technology,types of modulation also increase rapidly and traditional methods of recognition cannot meet the actual needs.In modern communication countermeasures,obtaining the modulation type of intercepted signals in time is the vital prerequisite for further information extraction and interference guidance.Aiming at the communication reconnaissance in modern electronic countermeasures,based on the supervisory concept of “Real-time +Accuracy” of actual combat,this paper designed a combined modulation recognition algorithm to recognize the modulation type of signals.This paper has studied and explored 2 goals with progressive relationship.First is analyzing the instantaneous characteristics,high order cumulants for the modulated signal,set the reasonable threshold values and judgment conditions to classify communication signals.Second,according to the similarity and specificity,the modulation signals are divided to several types to optimize the structure of the algorithm.Main research achievements in this paper include:(1).Study on the decision tree algorithm and high order cumulants algorithm,analyze the advantages and disadvantages of them and a combined modulation recognition algorithm is designed.(2).Study on the modulation recognition technology of MSK signal and mixed modulation signal.(3).Optimize the structure of the modulation recognition algorithm by the non-linear transformation to extract the characteristic parameters.In this paper,the algorithm was evaluated by simulated signals in Matlab and verified by the real communication signals in outfield environment.After the experiments of simulation signals and real signals,the real-time and accuracy of the recognition algorithm was verified.Furthermore,a reliable sub module was finally set up in the communication reconnaissance system.