Research On Detection Technology Of Frequency Modulated Continuous-Wave (FMCW) Laser And Radio Combination Fuze

At present,the combination fuze has become a new research hotspot.The combination fuze adopts various detection systems or different frequency bands in the same detection system or different physical detection fields.It can make up the deficiency of different detection methods to improve the anti-jamming capability.It can also use different detection methods to obtain more target information for data fusion and remove the obstruction interference to avoid early burst,mistakenly burst and improve the reliability of the fuze.In order to improve the anti-jamming capability and the reliability of fuze in complex environment,this paper puts forward the overall design scheme of FMCW laser and radio combination fuze based on the FMCW detection principle,and focuses on the anti-jamming theory of combination fuze and the theory of target height recognition in the detection area,the prototype of the combination fuze based on the common diameter structure is designed and implemented.Finally,the target distance measurement and anti-jamming experiment are carried out in different environments.Firstly,the aerosol backscatter interference model based on Mie scattering theory is established to quantitatively calculate the backscatter interference in the FMCW laser beat signal.A radio fuze ground detection model is established and the influence of the incident angle on the backscatter coefficient of the radio in different ground conditions is quantitatively calculated.Secondly,an adaptive filtering algorithm EMD-IT-Spearman based on Empirical Mode Decomposition(EMD)is proposed.The simulation results show that the algorithm can effectively denoise the nonlinear and non-stationary signal.Then real laser beat signal obtained in smoke environment is filtered by EMD-IT-Spearman,the result shows that EMD-IT-Spearman can maximize the retention of the target information,filter backscatter interference and high frequency noise,and improve the anti-smoke interference capability of the FMCW laser detection system.On this basis,a precision burst height control strategy of combination fuze is proposed.This mode selection scheme takes full advantage of the characteristics of different physical field in combination fuze.So the combination fuze own precise burst height control capacity in the electromagnetic interference environment and smoke environment.Again,a target height detection algorithm is proposed,which utilizes precise distance informationthe of laser detection system and the radio detection system in the combination fuze.At the same time,the angle of the shells,the assembly angle formed by the optical path of the laser detection system and the center of the radio antenna are considered,the target height can be highly identified.Thus the target height information can be used in the fuze detection process to avoid early burst,mistakenly burst and improve the reliability of the fuze.In the simulation environment,the real-time fuze and target intersection process is simulated and the feasibility of the algorithm is verified.Finally,the prototype of the combination fuze is designed and implemented.The laser and radio coaxial aperture transmission and reception structures are proposed,and the laser transmitting and receiving optical system and the double layer dielectric plate microstrip antenna are designed respectively.The common aperture structure has good electromagnetic compatibility ability.The laser and radio transmitter and receiver circuit are design through circuit multiplexing to reduce the space volume and power consumption.A FPGA-based echo signal processing platform is designed that is used to synchronize the digital signal processing of laser and radio beat signals in the combination fuze,and obtain the target distance information.The anti-jamming algorithm and taget height recognition algorithm are implemented in the host computer.A combination fuze test platform was built,and target distance measurement experiment was firstly carried out in non-interference environment.It was verified that the laser detection system and the radio detection system in the combination fuze were not interfered with each other.Then anti-jamming experiment was carried out in the smoke chamber,which proved that the combination fuze had stronger anti-interference ability.Experimental results confirm that the design scheme of the combination fuze is feasible.This paper provides former exploring research for combination fuze anti-jamming,target recognition and engineering realization of combination fuze based on common aperture structure.