| UWB radio technology is a research hotspot in recent years, time domain antenna has its special advantages in ultra-wideband radar, impulse radar, electromagnetic compatibility and other areas of transient electromagnetic field. It's put forward higher request to effectively radiate and receive the transient pulse signal. With rapid development of the modern wireless communication technology, there have been several narrow-band communication system. In order to reduce the interference between the UWB and several narrow-band communication system, it is necessary to study the band notched ultra wideband antenna. In addition, because of the limited application occasions, time domain antenna and UWB antenna of miniaturization, integration are also put forward higher request.Firstly, the background and significance of research on ultra-wideband radio technology and impulse radar are described in this thesis. The state of ultra broadband technology in radar and communication applications is expressed. Several typical time-domain antennas and ultra-wideband antennas are introduced. The research technology of time-domain antenna are summarized. High-power and miniaturization is a hot spot in time-domain antenna and planar UWB band-notched antenna research.Secondly, the relationship between time-domain antennas and ultra-wideband antennas are figured out. Requests and parameter performances of time-domain antennas are identified, and several transient pulse signals are analysed in frequency and time domain respectively. According to the radiating power and miniaturization required by impulse radar systems, the work processes of Blumlein line is analized. The Blumlein line which outputs Gauss pulse has been studied, and monocycle Gauss pulse would be generated when a short-circuit coaxial line connected to the output port of the Blumlein line, and it has been designed and tested by experiments.In the next part, according to the special requests of impulse radar system antenna, a resistance-patch loaded antipodal Vivaldi antenna is designed, which improves radiating performance, so the waveform fidelity is better and the waveform trailing is lower, and it has been tested by experiments. Then, an antenna array is designed using antennas mentioned above. A number of array elements achieve the electromagnetic pulse-phase synthesis in axial direction to realize beam focusing, the half power lobe width is narrowed, and a high gain radiation is realized.Lastly, for ultra-wideband radio technology in communications applications, some methods of how to generate bandstop characteristics are proposed. Besides, several miniature ultra wideband antennas are designed and fabricated, the experimental performance is satisfied with the band of 3.1 GHz-10.6 GHz, which meets the requirement of UWB technology. What's more, bandstops are generated in unnecessary band, such as 3.4-3.69 GHz(WiMAX) and 5.15-5.825 GHz(WLAN). |
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