Theory And Pivotal Technology Of Moving-target Detection And Tracking For UWB Impulse Radar

Ultra wideband (UWB) technology is widely attracting scholars and researchers because of it huge potential. In communication and radar fields, UWB technology has rapidly improved in recent years and may be causing a new technical revolution. As a kind of UWB radar, UWB impulse radar transmits and receives short pulse signals, then achieves some useful information of target from echo, such as distance, velocity and construction, etc. Relative to traditional radar, UWB impulse radar has very wide work band, so it has much advantage and huge military application merit. Because of the easier technology, short-range UWB impulse radar has been rapidly developed, and some productions have been manufactured. But there are few reports about middle- and far-range UWB impulse radar, so the theory and pivotal technology are expected to be deeply developed.In the period of "the tenth five-year plan", a UWB impulse radar system is built, its maximum detection range 5 km, and much study on the theory and experiment about middle- and far-range UWB impulse radar has been accomplished in our laboratory. This paper is subsequent study, and emphasizes on the theory and pivotal technology of moving-target detection (MTD) and tracking.Firstly, the pulse source of middle- and far-range is deeply studied. The influential factors on the stability index of a pulse source are minutely analyzed, and full-solid and high-stability pulse source units, based on avalanche dynatron, are designed. Through tow coherent synthesis of units, circuital and special types, high-power and high-repetitive pulse sources are designed, which is necessary for the middle- and far-range detection of UWB impulse radar.Secondly, the methods of UWB impulse radar moving-target detection are the study emphasis of the paper. Time-domain Doppler velocity-measuring is an important kind of the methods, and the principle is deeply analyzed, then it is pointed that the effective integration of echoes is the pivotal problem of velocity-measuring. To accumulate echo signals and improve measurement accuracy, three methods are put forward: arrived time estimating, subsection accumulating and subsection accumulating of arrived time estimating. And, their accumulating effect and applicability is analyzed. it is shown through a lot of simulation that echo signals can be effectively accumulated by forward methods in their applicability range. And, a new method of velocity-measuring, time-domain cancellation of echo waveform, is put up. The method converts time difference of arrival as voltage which is measured to compute the velocity of target.The theory of time-domain antenna array scan is analyzed. To realize time-domain antenna array scan, the pivotal problem is accurate delay-controlling to trigger of pulse sources. Contrasting to phased-array radar, the concept of timed- array radar is pointed out. According to the engineering requirement, eight-way delay-controller is designed, and many experiments are finished to validate the theory.Kalman filtering and tracking is traditional theory. It is introduced in moving-target tracking of UWB impulse radar in this paper.Finally, to realize moving-target tracking of UWB impulse radar, a full-numeric servo system which has excellent performance is designed. The experiment proves that the servo system can satisfy the requirement of tracking.