Research Of Radar Reconnaissance Detection System

The radio technology has been broadly used in various fields.Especially during war,the radio technology and equipment can be used to investigate the enemy's situation,and the radio equipment can also be used as the alarm equipment to provide favorable conditions to win the war.In general,the radio equipment frequently used in the war includes radar,reconnaissance system and other devices.They can be used to intercept the intelligence,process and analyze the obtained information and determine the enemy's location.Therefore,radar has a very important status in the history of modern warfare,and various military powers have attached great importance to research on radar.In general,after the information is collected by radar,it needs to be received by the receiver,and the radar receiver includes the digital receiver,analog receiver,digital-analog hybrid receiver and other types.Among them,the analog receiver can provide high response speed and real-time processing of signal.This is because in the channel of this type of receiver,the signal is mainly processed through the devices of amplifier,frequency spectrograph,oscilloscope,etc.,so it can significantly improve the signal processing speed.However,due to this processing method,the receiver algorithm has low flexibility,and it is difficult to convert according to the actual requirement,which has poor adaptability.After the digital receiver has received the signal,it can conduct digital processing of the signal through the reception channel and transfer it to digital signal.Therefore,compared to the analog receiver,the digital receiver is more flexible,which can provide conversion according to the actual requirement,but it has certain time delay,which cannot realize real-time processing of signal.For the radar receiver,its reception performance should be verified with specific evaluation system.In this paper,first,we analyze the radar signal monitoring technology and countermeasure principle;then,various signal recognition technologies,including the radar signal intra-pulse parameter estimation technology and signal collection technology,are combined to realize the design of radar reconnaissance and monitoring system construction plan;the radar signal frequency measurement algorithm and signal modulation recognition algorithm are analyzed based on simulation.With this system as the platform,we completed the FPGA analysis and verification of the algorithm;for research on the band channel,we mainly conducted test on frequency domain during collection of ADC data,and conducted related test of narrowband pulse coarse and fine scanning output.After performance test of the broadband and narrowband channel of radar signal collection board,the comprehensive performance of radar reconnaissance and monitoring system was verified.The signals within the range of 100MHz~3000MHz were divided into three sub-bands with instantaneous monitoring bandwidth of around 1GHz,and we converted their frequency to 1180MHz±500MHz through secondary frequency mixing.As a result,we could complete reception of signal with the sensitivity of-20dBm~-80 dBm within the range of 100MHz~3000MHz.Furthermore,we verified the accuracy of channelization and data collection plant,and the effectiveness of various signal modulation technologies.It could process the following types of signal: modulated radar signals of normal pulse,linear frequency modulation,nonlinear frequency modulation,frequency coding(2~3 frequency points),frequency agility,frequency diversity,PRI fixation,staggering and jittering;in the meantime,it cannot process more than 5 signals simultaneously.In this design,the simulation test and experimental verification are combined to improve the accuracy of research conclusion.