Study Of The New Fsk / Psk Modulated Signal

In the dissertation that extends based on the military item of '95' advance research, a novel multi-modulation technique designing radar signal waveform is introduced on the base of the analysis of the haven achieved frequency shift keying (FSK) and phase shift keying (PSK). The object of designing is to concentrated the signal energy in spectral location of most importance that contains target's information within the broad spread spectrum bandwidth.This method digitally modulates frequency and phase in the same time and produces pseudo-random FSK/PSK signal. Frequency code is not uniformity distribution and keeps to a probability distribution function defined by the spectral characteristics of the target of interest. The phase code is equally duality pseudo-random sequence and used to reduced the sidelobes of the signal correlation function. Contrast to others hybrid waveforms, the mostly characteristics of this signal is the randomicity and the adaptability of spectral. At every time of transmitting it, the signal certainly satisfy one statistic rule that the amplitude of spectrum is sameness and the time waveform is entirely unlikeness. It shows randomicity. The FSK sequence has the ability to represent arbitrary distribution of spectrum and therefore has the adaptability of spectral. In the dissertation, the signal is analyzed theoretically, studying its specialitis used in radar(frequency spectral, ambiguity function range resolution, volcity resolution and Doppler toleration); studying the correlation speciality the signal with one statistic rule; studying the basis of modeling using radar impulse response and provides the ground of frequency code; explaining target'pole information estimation through a example of a model of multi-scatter centers; giving the two applications of the correlation receiver; analyzing the result of computering correlation and cross-correlation ceveiver using Matlab in without noisiness.Then come to the conclusion that the signal has the efficiency of big BT, high resolution, low probability of intercept, anti-jam and randomicity . The adaptability of spectral allows the radar to more effectively detect or track the target. Additionally, itsfrequency distribution showing the information of the target and its waveform having high range resolution make it important sense to target recognition and imaging.