Simulation Research On Signal Modulation Identification And Parameter Estimation Of Ground Wave Radar

Radar signal modulation identification and parameter estimation are the important steps of radar reconnaissance and confrontation. This dissertation analyses lfmicw and pmpcw which ground wave radar commonly using .The process simulation of modulation identification and parameter estimation is under the Gaussian white noise background.Firstly, the dissertation introduces the calculation method of the analytical signal instantaneous range, instantaneous frequency and instantaneous phase. It lays the groundwork for future feature extraction. Then, it introduces mathematical models of LFMCW and PMPCW, inspects their characteristics in the time domain and frequency domain through simulation. At the same time, it gives the time-domain waveform and spectrum map. Instantaneous frequency of LFM is linear. The frequency of the phase coded signal has a sudden change when the element changes. Different signals with different characteristics of the instantaneous frequency, modulation recognition in this dissertation will be based on the instantaneous frequency characteristics of the signals.After that, it introduces the instantaneous frequency extraction algorithms, mainly including instantaneous correlation algorithm, phase reconstruction algorithm, the short time Fourier transform, Wigner-Ville distribution, wavelet analysis and zero-crossing detection. In this dissertation, it uses the instantaneous correlation algorithm. It can gain a high recognition rate of signals with less operation.Next, it introduces the extraction method of the time-domain parameters such as pulse width, pulse repetition rate and pulse range. In this dissertation, it uses radar time domain parameter extraction algorithm based on instantaneous autocorrelation and analyses the extraction accuracy in different signal-to-noise ratio. Compared with the traditional algorithms, it can get high pulse measurement accuracy. The algorithm is simple and needs less operation.On the basis of the instantaneous frequency and time domain parameter extraction, it researches on the modulation recognition method of ground wave radar signals and the success rate in different signal-to-noise ratio. Ground wave radar parameter extraction is based on the parameter extraction of each pulse. The process simulation of modulation identification and parameter estimation is in different signal-to-noise ratio. According to the simulation results, it calculates estimation error. It can be seen that the algorithm has a high accuracy.In this dissertation, the research is based on the background of single-carrier frequency, additive white Gaussian noise. The background of multi-carrier frequency and non-additive white Gaussian noise will be the future research direction.