An ultra wideband radar system based on a coherent emission of an Ultra-Wideband antenna array using photoconductive switching devices is proposed. The triggering process is obtained by excitation of semiconductor samples in linear mode using a picosecond laser source. The emitting antenna system and the receiving antenna developed by the research Institute XLIM, present some specific qualities suitable for radiation and measurement of ultra-short pulses. The optical control of the sources allows to sum the radiated power and to steer the transient radiation beam accurately. The experiments realized with this optoelectronic array validate these two concepts. An other way of improvement of these systems is proposed. It consists by using bipolar pulse generators.
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