Automatic Testing Software For Complex Modulated Radar Signals

In modern wars, with the wide use of radar technology, the working environment of radar is becoming more and more complex. The electromagnetic wave in space is more intensive and the signal density of the electromagnetic threat environment is also unprecedented than before. All kinds of jamming signal affect the radar performance seriously. Therefore, the current new radar always adopts complex modulation systems to generate the radar signals, which are quite different from the traditional's in the form of the signal, and these parameters and forms are more flexible and changeable. Therefore, analysis and research on the detected signals, extraction of its main feature, is of great significance to identify the information contained in radar signals. Based on the above situations, this dissertation designs and develops an automatic testing software for complex modulated radar signals, which is able to analyse the parameters automatically according to the form of the radar signals.Based on the Visual Studio 2010 development environment, this software is designed by MFC library and C++ programming language. It adopts the interface layout of dockable window to realize the flexible switch between the tabbed interface and the tile interface, and the software's interface is beautiful and convenient for users to operate. The overall design of the software adopts modularized design philosophy, and divides the software into four modules: the analysis module, the display module, the auxiliary display module and the interface module. The signal processing algorithm of the software analyses the signal from three aspects: time domain, frequency domain and time-frequency domain, and extracts the information of the signal parameter comprehensively. Among them, In time domain analysis, it adopts the smooth filtration algorithm to reduce the influence of noise, then uses the modified threshold method to eliminate the burr and gap caused by noise, and finally uses the average density distribution method to measure the pulse amplitude, thereby, it measure the other time domain parameters of the pulse. In frequency domain analysis, it adopts the short-time fourier transform method and the Decimation In Frequency method of the fast Fourier transform to obtain signal spectrum to measure the signal's frequency domain parameters. Cohen time-frequency domain distribution method mainly includes Wigner-Viller, Pseudo Wigner-Ville, Choi-Williams and Cone-shaed. In the end of this paper, we design a set of test cases to verify the correctness of each functional module.The automatic testing software for complex modulated radar signals designed in this dissertation is able to carry out one-click and auto measurement of various kinds of radar signal parameters. The automatic tesing system, composed of the software, radar equipment and spetrum analyzer connected by the LAN/GPIB interfaces, can realiable measurement of the radar signals.