Miniaturized X-band Navigation Radar Receiver Technology Research

The main purpose is to do research on miniaturization of the front end receiver for certain boat-carried direction-oriented radar, so as to minimize the producing cost of it with the performance and coherence guaranteed. The miniaturization could lead to future mass producing.The developing trend of the front end receiver for radar and its utilization in boat-carried direction-oriented radar are described in chapter one, according to which, the structure of the front end is decided. In chapter two, the principle of VCO is introduced, the influence, coming from phase noise of local oscillator, on performance of the front end of receiver and the factors that may have effect on phase noise in oscillator designing are analyzed, so the X band VCO needed is designed as regarded. In chapter three, after presenting the working principle of mixer and image-reject mixer, some problems which should be paid attention to during the mixer design are discussed. In chapter four, the basic theory of low noise amplifier is introduced, some factors that might affect the noise performance of radar receiver are analyzed. In chapter five, the design scheme and specific design processes of the front end receiver for certain boat-carried direction-oriented radar are given. Through testing, its noise figure is 5.5dB, mixing gain is 5dB, its image frequency rejection adds up to 19dB, which all meet the requirements for the system (NF=7.5dB, Gain=3dB) .The designed front end of received has been applied in certain boat-carried direction-oriented radar to debug, which functions from -40-70℃. In the end, the existing problems of this front end of receiver are analyzed, along with the improvement direction and means.