Potentials of ultra-short-pulse time-domain scattering measurements

This article illustrates the potentials of ultra-short-pulse time-domain sc attering measurements, and describes a facility to perform such measurement s. The main advantages of measuring in the time domain are the high range r esolution and the relatively simple measurement setup. A time-domain radar cross section measurement of a flat plate is performed, to illustrate the a dvantages of such methods over a conventional frequency-domain setup. The m easurement was performed with a sampling oscilloscope, a pulse generator, a nd two 2-12 GHz ridged-horn antennas. Because the horns were not designed f or transmitting transient signals, an additional system-response measuremen t, in combination with a software deconvolution algorithm, restored the imp ulse response of the object under test. Further processing separated the re sponse of the object from clutter. A comparison of the time-domain data wit h calculated and measured frequency-domain radar cross sections shows good agreement. The high range resolution (100 ps) enabled the separation of sca ttering mechanisms (i.e., reflection, single and multiple diffraction). It is concluded that ultra-short-pulse time-domain measurements could be very beneficial.