Study Of Receiver Technology Based On Intermediate Frequency Digitization

Passive detector and location system belongs to the electronic detector/aiding system, which is an important part of Electronic War(EW) System. It detects, recognizes and traces aircraft by processing the electromagnetic wave signal reflected by aircraft, which is transmitted by broadcasting station, TV station and even base station of mobile system, so it has been developed by many countries until now, and the digital receiver technology has been adopted or will be adopted within the receiver system. Within this paper, the IF(intermediate frequency) digitized receiver platform technology will be studied, according to the requirements of the army project"PCL(passive coherent locater) system based on TV transmit station". This is very useful in both theory study and engineering development.There are three key issues within this system: technology of analyzing pulse signal,time synchronization technology and accurate location technology. The traditional analog EW receiver is usually used to demodulate the radar signals and convert them into video frequency pulses, but it could not work well when they deal with these key technologies. Sometimes they report some signal that does not exist, and other times they miss some signal. To effectively solve these issues, the digitized receiver scheme is studied within this paper. Because of the digitized processing in IF or RF(radio frequency), those issues, such as the temperature excursion caused by analog circuit,the gain variation,DC excursion and so on, will be solved effectively. This will help the system to gain excellent stability.Digitized receiver is made of RF converter unit,A/D converter unit,spectrum analyzer unit,encoder unit and so on. And A/D converter and...