Stepped Waveform Time-Modulated Multibeam Array With Beam Suppression Functionality

Time-modulated array (TMA) naturally generates a large number of sidebands to achieve multibeam radiation. Conventional multibeam TMAs using rectangular modulation signals lack design flexibility, and recent high-flexibility designs are mostly theoretical without experimental validation. To balance flexibility and feasibility, this letter proposes a stepped waveform multibeam TMA with beam suppression functionality. It uses in-phase/quadrature (I/Q) time modulators with digital attenuators and 0/pi phase shifters to independently generate stepped waveforms in both in-phase and quadrature channels. These waveforms can fit various complex modulation signals, enabling the realization of diverse multibeam radiations and the suppression of specific beams. Experimental verification is conducted on the same TMA hardware system, achieving a 5-beam TMA and a 4-beam TMA by adjusting the time-modulated signals. The suppressed beams achieve a suppression level of up to -36 dB, making it effective for anti-interference.