Abstract :
A compact ultrawideband (UWB) monopole antenna with a small size of 60 mm × 60 mm × 30mm and operates over the frequency band between 1.4 and 2.8 GHz, excited by a pulse with 1ns duration has been design. The subnanosecond pulser, in which avalanche transistor is used as its switch, can generate high repetition and stability short-pulse. A 12 class avalanche transistor Marx circuit is used to increase the peak power of the pulser. The pulse with 230 ps width, 350 V Amplitude (measured on 50 Ω load) and a tailing less than 10% was achieved. When the pulse is used to feed the proposed antenna, the antenna shows good radiation performance. The antenna is optimized so that the antenna has a very wide bandwidth, good time-domain radiation performance. Experimental results are good agreement with the simulations offered by the commercial software (CST MWS).