Research On Wideband Digital Reconnaissance Receiver

Modern War battlefield electromagnetic environment is more and more complex, the electronic warfare of the opposing sides compete for control of the electromagnetic spectrum usage is increasingly fierce. The receiver which as an important part of electromagnetic battle is faced with more complex, dense, non-cooperative, rapidly changing electromagnetic signal environment. In order to meet the needs of military requirements under the current situation, the development direction of electronic warfare receiver technology is forced to large field, wideband, full-polarized, high sensitivity, large dynamic range, more complex signals simultaneously receiving and processing. From the development of electronic warfare receiver, it is bound to go the development way of precision and digital, the demand for signal processing in the electronic warfare receiver with different functions and performances will be satisfied by the flexibility, accuracy and highly controllability. Wideband Digital Reconnaissance Receiver is an important part of modern electronic warfare system, which uses high-speed A / D converter to convert analog signals into digital signals using digital signal processing technology to complete the analysis and identification of signals, it is possible in a very wide within the frequency range of an electronic environment for testing, measuring and access to information, thus completing a variety of electronic reconnaissance missions. Currently, broadband digital reconnaissance receiver has become an important research topic in the field of electronic surveillance.This article is based on the research of precious people, the channel technology for wideband digital receivers, dual-rate sub-sampling techniques, application polyphase structure filter bank and short-time Fourier transform(STFT) techniques were analyzed and discussed, two efficient wideband digital channelized receiver program are proposed.A new kind of digital channelized receiver is proposed,which is based on double sub-Nyquist sampling technology and digital channelized technology. Analysis of the structure and implementation of the principles of the system, discussed the system for detecting and measuring the signal problem, studied the dual rate under the conditions of under-sampled signal parameter measurement method based on the remainder theorem and the algorithm simulation; use the sampling system for large bandwidth signals, it is possible to effectively alleviate the traditional way of sampling high-demand hardware problem.Wide bandwidth signals could be de-tected by this system,while the transient dynamic range of the receiver can be improved with analog digital convertor(ADC)when high bits are selected. In this paper,for AD sampling resolution can not be achieved at a higher rate baseband sampling will produce aliasing(frequency fuzzy) problem, use remainder theorem to solve fuzzy, and under different SNR its simulation.Another is based on the STFT digital channelized receiver polyphase structure. Analysis of the structure and implementation of the principles of the system, discussed the system for signal detection and measurement method, and the algorithm simulation. Using this system for large bandwidth signal processing, not only to improve the operating speed of the system, and can reduce the cost of the hardware resources of the system.