| Ultra-wideband (UWB) sources and antennas are of interest for a variety of potential applications that range from transient radar systems to communications systems. The generation of ultra-wideband pulses is a challenging problem that involves generating pulses with fast rise times on the order of 100 ps and voltages of more than 10 kV. Pulsewidths from 130 ps to a few nanoseconds (ns) are possible. A critical step involves switching high voltages with precision. The use of both gas and oil for the switching medium has been accomplished with varying results. Photoconductive semiconduction switches are a completely different type of switch than those currently used in pulsed power applications. The most important attributes of PCSS are jitter free triggering, low inductance and capacitance, fast rise time, fast recovery time and high repetition rate. Among PCSS, GaAs PCSS have many advantages over Si in response speed, the transfer efficiency of light into electricity and high voltage resistant, especially they can operate in a nonlinear mode with high gain which can reduce the triggering optical energy by 3-5 orders of magnitude comparing to the conventional linear mode. This makes it realistically possible to realize the miniaturization, practicality and integration of the system of PCSS. So it will be applied widely in ultra-wideband source circuit.In this paper, Auston circuit, Blumlein pulse forming line is introduced and their difference is given. The experiment system is set up and the PCSS samples are tested. The Blumlein microstrip photoconductor switch is designed and the voltage transmission efficiency of 63.1% has been obtained in experiment under resistive and linear operational pattern photoconductive semiconductor switches condition. Moreover, the ultrashort pulse is radiated through slot antenna.In this dissertation, slot antenna and the integration system of circuit and antenna is studied in theory, simulation and experiment. And antenna directivity, side lobe level and input resistive are studied , in order to design slot antenna and integration system on circuit and antennaThe integrate system on circuit and antenna investigated in the dissertation has good application foreground in both scientific research and engineering. The array of this system can realize the synthesizing of space power,the array controlled by light of phase controlling, and enhance electromagnetic interferential effect largely. The system designed in this dissertation has some advantages such as small volume,low facture cost,array forming easily. |
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