Theory And Test Of Target Detection For Ultra-Wideband Radar

The hopeful potential of UWB (Ultra Wideband) impulse radar is attracting many scholar and researchers to devote into its study, and a new technical revolution in radar field is coming maybe. In this paper, theory and test of impulse radar system, especially which's on mid/long-range, are discussed.Theory of target detection for an impulse radar system is analyzed minutely. Firstly, an expression is given to describe the impulse's waveform spreading effect by target's moving, and measurement principles of range, velocity, and angle, are discussed. Then, couplings among measurement's fields of impulse radar are mentioned, and the ambiguous functions of one or two dimensions are remarked exactly. Moreover, the analytic expressions, for both infinite and finite number of pulses, are deducted originally, and their physics essences are pointed out. Furthermore, the impulse radar equation in time domain is derived from using a time delay factor particularly, and according as the equation, the model of ideal optimized correlation receiver in time domain is explored out.Both transmitter and receiver of impulse radar are analyzed deeply. Firstly, the basic parameters of them are defined strictly. Then, sub-sources with high stability are designed out, theory of pulse sources' open-loop synchronization and synthesis is studied, and a series of full-solid high-stability pulse sources with 4 or 30 MW peak power are realized, using synchronization and synthesis technology. Similarly, the model and performance of the ideal optimized correlation receiver in time domain is discussed, and a series of receivers realized, including both leading-edge detector and quadrature demodulation receiver.Some signal processing algorithms for impulse radar are introduced. Based on the thought of distinguishing time-domain feature and adding software wave-gate, algorithms of both time domain RFI suppression and double-threshold recognizing detection are pointed out. Based on the slope difference between echo and clutter or RFI, a Time-Domain Slope-Filter Clutter Suppression (TDSF-CS) is explored out, which is fitter for lower SNR.Finally, a prototype of mid/long-range impulse radar and its outdoor test are shown.