If we want to make use of Doppler technique of the ships in navigational radar, first we must get the Doppler frequency, but the related circuit is very complicated, therefore, the cost of the radar is very much.

To develop the passive acoustic detecting intellectual mine fuse of antiarmed helicopter,this paper presents a method of the motional parameter estimation of he-licopter target through processing the Doppler shift equation of helicopter noise signal byweighted least square algorithm on the basis of analysing helicopter noise signal received inthe acoustic detecting array.

Based on traditional techniques of passive location,single-station passive location is achieved by adding observation information,which is bearing and Doppler frequency joint location method.

When detecting the high-speed moving target by using phase-coded signals,Doppler frequency compensation is necessary because of the Doppler frequency sensitivity of phase-coded signals.

Amplitude distortion and phase distortion of signal caused by radar transmitter and receiver and Doppler frequency produced by target radical movement are three key factors that influence the performance of pulse compression.

According to the principle of view the Doppler frequency detection, the detector makes up of the transmitter, the transfer circuit, receiver and signal processing circuit.

Errors caused by the aircraft motion and orientation lead to the errors of the Doppler centroid and Doppler rate,thus some significant distortions appear in images.

A new method for estimating the Doppler rate in synthetic aperture radar (SAR) imaging is presented based on the four-parameter Chirplet decomposition of the signal in a range bin.

This paper analyzes the relation between the Doppler rate and phase gradient,and proposes algorithm for the Doppler rate estimation with the PGA,then the performance of this algorithm is verified by the computer simulation data and airborne SAR data.