A Study Of The Optimization Design Of Radar Anti-jamming Waveform

Radar transmitting signal not only determines the signal processing method, but also directly affects the other important indicators such as the system power, precision, resolution and anti-jamming performance, therefore radar waveform optimization design becomes more and more important. The launch of radar waveform design is based on the target environment and target information requirements. For one thing target environment requirement is determined by the target's radar working environment, for another target information demand is determined by the type of radar transmitting signal. Main task of radar waveform optimization design is according to the tactical requirements of a given target environment conditions to choose the appropriate signal, setting signal type and related parameters, so research on optimization design of radar waveform became the most important part of radar applications.With the continuous development of radar now, radar waveform optimization design has become an important subject research, and also is an important branch of radar system. The radar waveform of commonly used optimization design is introduced firstly, including to the theories of the nonlinear frequency modulation signal, linear frequency modulation signal, noise frequency modulation signal and the phase coded signal, all kinds of waveform analysis method of lower sidelobe and doppler sensitivity, and relevant computer simulation verification. Then this thesis focuses on how to produce multiple sets of orthogonal signal when interference is dexterous forward type interference because interference and signal waveform characteristics is the same. It is more sensitive to doppler frequency when the phase encoding signal is long, and the alternative orthogonal phase coded signal is corresponding reduced, so the linear frequency modulation signal generated on upper and lower frequency modulation and the nonlinear frequency modulation signal based on different S curve of frequency modulation is added into multiple sets of orthogonal signal. In addition this thesis put forward a new method for the optimization of pulse pressure filter based on genetic algorithm, and it makes radar stronger anti-interference ability, especially the ability to resist interference and forwarded when radar transmit signal and interference signal is incomplete orthogonal.Finally, not only common radar waveform and orthogonal waveform optimization design platform but also source of radar simulation software platform is established on the background of practical application of radar, the waveform of optimization and design, performance analysis and data encapsulation.They are satisfied to the actual demand of emission waveforms through setting signal type and related parameters in the interface. Commonly radar waveform and orthogonal waveform optimization design platform is mainly depending on the type of different transmitting into the linear frequency modulation signal module, nonlinear frequency modulation signal module, phase encoding module, the orthogonal phase encoding module and noise frequency modulation module.All of them are processed by matched filtering and mismatch filtering, all kinds of the method of lower sidelobe and analysis of doppler sensitivity according to different signal types. What's more,the source of radar simulation software platform is mainly to simulate the multi target data process baded on different pulse under different waveform in the transmission and reception scenarios. The abstract the algorithm and programming are embedded in the image of the specific interfacestructure and good choice of the mode of the signal, the main task of radar waveform optimization design is accomplished effectively.