| Impulse radar (IR), which radiates, receives and processes transient impulse signals, is a new style of Ultra-wideband (UWB) radar. It operates on a large bandwidth and presents a great potential in target discrimination, target identification, rejection of clutter and multipath interference, stealth aircraft detection, fine range imaging. Recently,it has been generated broad interests in the research community. Since there is a great value to develop a receiving antenna used in UWB carrier-free impulse radar system, and the study of power combining theory for antenna arrays in time domain is also an important subject.UWB impulse radiating antenna and its application in impulse radar are involved in this thesis. First, the characteristics of UWB antennas and time domain antennas are summarized, and several kinds of UWB antennas for impulse radiation are analyzed, in which the tapered slot antenna (TSA) is introduced in detail. And then, a TSA is developed for short-pulse radiation based on the requirements of the application. The radiation characteristics of the antenna are calculated in models built in CST. Through the comparing between the simulated results and the measured results, some improvements are made to the TSA. To satisfy the high gain of radar application, A TSA array is made. Meanwhile, a time domain measuring system is designed and used to measure the array. Time domain waveform, normalized energy pattern, normalized peak-amplitude pattern are employed to analyze the measuring results of the antenna array, and the time domain characteristics of the UWB antenna arrays for impulse radiation is summarized. At the end of this paper, the antenna array is applied in the target detecting impulse radar system. Some results are derived from a long time outdoor experiment, and some valuable rules are summed up to the impulse radar target detection. |
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