Radar Frequency Synthesizer Module And The If Receiver Module Design And Implementation

Many Radar systems have been used in the modern warfare. Radar operating frequency has developed from decimeter wave bands and centimeter wave bands to millimeter wave bands. The solid-state millimeter radar has advantages of small size, light weight, more precision distance and azimuth resolution and more Doppler frequency shift. According to the technical and tactical requirements of a certain type of radar, a frequency synthesizer module and an IF receiver module have been designed.Frequency synthesizer module is a very important part in the radar system, which provided coherent frequency source. In this paper, the frequency synthesizer module provides system clock (100MHz), A/D clock (400MHz/1.2GHz), D/A clock (2.4GHz), the first LO(S Band) and the second LO(X Band) for the radar. PLL, PLL and frequency doubter, double PLL and mixer are used in the frequency synthesizer module. The most difficult part in designing is spurious suppression. After two rounds of design, the module has been completed.IF receiver module is a super heterodyne receiver. There are three channels in the module, each channel includes amplifier, mixer, filter and IF amplifier and automatic gain control circuits (AGC). The difficulties in designing are amplitude/phase consistency and spurious suppression. The AGC circuit for different pulse widths and pulse periods is another difficulty. After two rounds of design, the module has been completed.