Time domain synthesis of pulsed arrays

Pulsed arrays are becoming popular in new ultrawideband applications to enhance the robustness of transmitted and received signals in complex environments and to identify the angle of arrival of multiple echoes. A global synthesis technique is here proposed to shape the array field in accordance to given angle-time constraints. The synthesis problem is cast as the inverse Radon transform of a desired array mask, applying the alternate projections method to include constraints over the input signals' waveform and to improve the synthesis robustness. The unknown array currents are generated as linear combinations of Hermite--Rodriguez functions in order to achieve a simple and realizable beamforming network. The effectiveness of the method is demonstrated by many examples. Index Terms--Alternate projections, array synthesis, pulsed arrays, Radon transform, space-time beamforming, ultrawideband (UWB) antennas.