Ultra-wideband Linear Fm Signal Channelized Receiver Technology Research

With the development of radar technology, the ultra-wide band radar is developed as one of important directions of new radar system. The low probability of intercept (LPI), the ability in super-resolution and anti-jamming of Ultra-wide band radar challenge to the traditional receivers. It is urgent to research and develop new reconnaissance receiver with the properties of wide band, high sensibility, wide dynamic range and accuracy signal parameter estimation. In this dissertation, the analog-digital channelized receiver is studied. The optimized system, spectrum reconstructing and accuracy signal frequency estimation algorithms are researched. The main achievements of the dissertation are included:(1) The limitations of the traditional channelized reconnaissance receivers indicate that it cannot be used to receive the ultra-wide radar signal. It is pointed that the ultra-wide receiver must satisfy ultra wide monitoring band, high sensibility, wide dynamic range and almost real-time response.(2) An analog-digital channelized receiver is given. Two key techniques of this receiver, including how to achieve data conversion effectively and frequency estimation precisely, are introduced briefly. The change of channelized LFM signal is discussed. It points out that the signal which is located on the edge of filter is changed but still keeps the characteristics of LFM signal, so traditional LFM signal parameter estimation algorithms can be used.(3) The effects of parameters of analog-digital channelized receiver on LFM signal parameters estimation are discussed. Based on the results, the structure of the receiver is optimized to obtain better performance of parameter estimation.(4) The methods of signal spectrum reconstructing are discussed. A method, which uses the spectrum of output signals and response of digital filters to restrict the LFM signal spectrum, is studied.(5) Based on subspace orthogonal algorithm, a method for estimating the parameters of wide-band chirp signal is studied. It is shown that accurate estimation can be obtained for wide-band chirp signal even under low signal-to-noise ratio (SNR)...