The System Of Weather Detection In The Primary Surveilence Radar

The primary surveilence radar of all solid transmitter is studied for the international and the civil aviation or the military aviation. It would change the situation that is most of the primary surveilence radar in the CHINA are imported. The function of weather detection is one important part of the primary surveilence radar. This article describes the function which how to accomplish weather detection in the airway under the condition of one radar system. The radar serves for plane starting and arriving, and provides alarm of dangerous weather.This weather detection system is named of weather channel of the radar. The antenna and the transmitter of the radar are used for both of the weather channel and target channel. Weather signal is picked up by signal process after the echo signal is magnified in the receiver. The dynamic range of receiver is made sure 90dB and the sensitive of it is - 107dB. The receiver has two unique channels for high and low beam. Each of them is composed of high frequency amplifier, intermediate frequency amplifier and sampling, digital phase uprightness intersector, DDS and the S band signal inspirator for the transmitter. The receiver adopts dynamic range compressing, logarithm amplifing circuit and STC control. The MTD filters are applied in the digital wheather signal processing to delete false echo, jam and etc. The value of sidelobe of digital pluse compress is about -40dB. The channel performs detecting the intensity of weather signal and divides them into 6 grades. The teiminal displays weather map of 6-levels contours.This system has been used in the primary radar reseached by the CETC 14th Research Institute.It has been proved successful.