TMA–FDA Range-Angle Beamforming With Periodic Linear-Phase Time-Modulating Waveforms

Frequency diverse arrays (FDAs) provide range-angle time-invariant transmit–receive beamforming, although a fine focus of their radiation patterns is costly since high-resolution mixers and phase shifters are required. An innovative approach to FDAs is proposed in which mixers and phase shifters are replaced by the application of periodic linear-phase time-modulating waveforms to the antenna excitations implemented with 2-bit variable phase shifters controlled with periodic
on–off
instants of binary sequences, which leads to a simple and precise method for FDA beam focusing.