A pulsed power source to drive an innovative autonomous scanning UWB radiation system

Abstract

Ultra Wide Band (UWB) antenna arrays offer the possibility to generate a wide band signal in a sharp direction, which can drastically improve the detection sensitivity. With a configuration including as many antennas as generators, an UWB array presents the advantage of increasing the radiation power on one hand and offering the agility to the array on the other hand. Indeed, the application of time delays between the feeding pulses of the antennas permits to steer the radiated fields in each wanted direction and to realize a coherent sum of each initial power. However, a major difficulty with such a configuration is the minimization of the radiation source jitters, to obtain the best synchronization possible. A solution consists of using pulsed optoelectronic devices, operating in linear switching regime, which permits to bypass this difficulty and to obtain ultra-short electrical waveforms with small temporal jitters (2ps typically). Many applications such as transient radar cross section (RCS) measurements, UWB synthetic aperture radar (SAR) and high power UWB radiation source can be developed by using such systems. In this paper, the design of an innovative autonomous scanning radiation system will be approached. The first experimental results will be also presented. These results are essentially focused on the high voltage pulsed power source which is previously described. This source aims at driving the pulsed optoelectronic devices. It consists of a series-connected IGBTs component.