A Research On Technology Of K-Band Multi-Channel Radar Front-End

Since the discovery of radar technology,it has gradually been improved.In the fields of automobile autopilot,imaging and medical instruments,it has been widely used and has raised higher demand.Smaller size,lighter weight,shorter measurement time,lower cost,lower power consumption,wider bandwidth,higher sensitivity and greater dynamic range are required to achieve.This paper develops a K-band low-power low-cost radar front-end that can be used to measure target distance,speed,angle and imaging based on the frequency modulation continuous wave system and multi-channel structure,and combines a vertically connected array antenna to achieve a compact structure.The following is the main work done in this paper for the development of important components of the radar front-end:1.According to the requirements of the subject demand,appropriate design plan was formulated.2.According to the negative resistance type and the feedback type,the oscillation principle and design method of the oscillator were studied respectively,and a voltage controlled oscillator was developed: the output frequency range is 5.85GHz-6.1GHz,the output power is greater than 5 dBm,and the power consumption is 0.05 W.3.The basic theory and design method of the low-noise amplifier were applied,and a K-band low-noise amplifier and an X-band small-signal amplifier were developed.In the frequency range of 23.4GHz-24.4GHz,the gain of K-band low-noise amplifiers is greater than 20 dB,the gain flatness is less than 1dB,and the noise figure is better than 3.5dB;in the frequency range of 11.7GHz-12.2GHz,the gain of the X-band small-signal amplifier is greater than 11 dB,and the gain flatness is less than 2dB.4.The theory,structure and design method of FET active mixer had been applied. An active mixer had been developed in the form of drain mixing: from 23.4GHz to 24.4GHz,the frequency conversion gain is greater than-10 dB.5.The theory of FET active frequency doubler had been applied,and an active frequency doubler had been developed: from 11.6GHz to 12.4GHz,the output power of the doubled frequency is-2dBm,and the fundamental wave suppression is better than-25 dB.6.The basic theory of microstrip rectangular patch antenna and array antenna had been applied,the characteristics of the vertical interconnection structure had been analyzed,and an array antenna group in the form of back feed had been developed: from 23.4GHz to 24.4GHz,the transmit antenna gain is greater than 18dBi,the receiving antenna gain is greater than 17 dBi,and the VSWR of the ports are better than 1.5.7.Finally,the designed important components were combined in a reasonable layout to complete the radar front-end,and the test and debugging of the entire front end were completed.