Research On The Key Technologies Of The W-band Dual-Polarization Monopulse System For Multi-Mode Seeker

The detection and recognition of targets under complex electronic countermeasures and background clutter are the key problems that need to be solved for Terminal Guidance System(TGS).The multi-mode guidance technology is the inevitable trend of the terminal guided weapons because the recognition ability of a single mode TGS is limited and it hard to meet the requirement of “Fire and Forget”.The Laser/infrared/millimeter-wave combined tri-mode guidance technology has the advantage of all-weather,high target recognition precision and anti-interference ability,and thus make it the best choice for general TGS.The full polarization scattering parameter and the high range resolution image of the W-band millimeter-wave radar can characterize the internal and external characteristics of the target from different dimensions.Thus,to a certain extent,will improve the ability of target identifying and anti-jamming capability.The further combination with the infrared image can significantly improve the target recognition and anti-jamming capability,and improve the guidance precision of the composite TGS.In this situation,a W-band planar dual-polarization detection system for laser/infrared/millimeter-wave tri-mode seeker is presented in this paper,and the key technologies in this system are studied.The main work is as follows:1)The design and optimization of the tri-mode seeker.Several different composite schemes for the tri-mode seeker are studied in detail.The combination of planar millimeter wave antenna with a reflect laser lens and a catadioptric infrared optical system is selected as the best solution for common aperture tri-mode seeker.To overcome the limitation of the traditional millimeter wave seeker in tri-mode seeker application,a multi-subarray digital monopulse radar system based on planar dual polarized antenna is proposed.The antenna with multi-subarray architecture has the beam adjustment ability,which can correct the beam distortion and aiming error caused by the optical system.By using the space power synthesis technology,it can also overcome the restricted output power of the w-band devices.More over,the effects of the amplitude and phase error on the power synthesis efficiency,the accuracy of digital monopulse angle measurement,the circular polarization axis ratio and the accuracy of polarization scattering matriex parameter extraction are studied.2)Study on W-band full-corporate-feed planar dual-polarized antenna.A W-band fullcorporate-feed planar dual-polarized antenna is proposed based on a TM210 resonant mode radiator and two-layer siw-feeding network.The dual-polarization feeding network is achieved with the "one feed multiple" radiator and the offset reverse feeding technology.Moreover,the feeding network is easy to achieve the horizontal expansion.The antenna has the advantages of simple structure,low profile and low cost.An 8×8 dual-polarized antenna subarray is optimized and designed.The measured bandwidth is wider than 4GHz,the gain is above 23 dBi,and the cross polarization level is better than 30 dB.Based on the 8×8 double polarized subarray,a dual-polarized antenna array for tri-mode seeker is designed.The simulation result shows that the antenna can meet the requirements of composite TGS.3)Study on the miniaturization and planarization of W-band transceiver.A planar Wband transceiver is designed,assembled and measured considering the miniaturization and thermal design.The planarized filter and low loss interconnection are further studied.Considering the requirements of both the electrical and mechanical properties of the transceiver,a low-cost,easy-to-assemble and quasi-planar "embedded" waveguide filter is proposed and fabricated.To further improving the integration level,a GaAs SIW filter based on a new singlet was proposed,and a multi-functional chip has been designed based on the filter and a balanced mixer.The assembly process of the transceiver is simplified based on the multi-functional chip,therefore.Besides,the equivalent structure of the W-band wire bonding structure is analyzed and the corresponding matching structure is given.A low-loss matching interconnection between W-band devices is realized for further improving the reliability and stability of the W-band transceiver.4)Study on the calibration method for multi-channel amplitude and phase error.A multichannel amplitude and phase calibration method based on six-port technology is proposed.This method only needs the existing transceiver and embedded calibration network between the antenna and transceiver.Then,the amplitude and phase errors of each transmit and receive channel in the transceiver can be measured and calibrated.Based on the GaAs process,a sixport calibration chip,which can be directly integrated in the transceiver,is designed.The power splitter,coupler and diode detector of the calibration chip are optimized.Besides,the calibration method is verified based on the waveguide structure.The results show that the measurement accuracy is better than ± 4° in the range of 0 ~ 360°,which can meet the required accuracy of the system very well.The above work and results have laid a foundation for the design and engineering realization of the laser/infrared/millimeter wave composited tri-mode TGS.