Gain Improvement in Time-Modulated Linear Arrays Using SPDT Switches

Time-modulated linear arrays (TMLAs) based on single-pole-single-throw (SPST) switches usually have higher reduction in gain due to the sideband radiation and power absorption of the off-state absorptive switches. In this letter, a novel approach is proposed to improve the gain of TMLAs using single-pole-double-throw (SPDT) switches. The gain of the proposed TMLA can be improved significantly by controlling two array elements with each SPDT switch. Moreover, the proposed TMLA has a constant instantaneous directivity, which is favorable for some applications. Numerical results are presented to illustrate the proposed approach by considering a 16-element linear array with a -30 dB sidelobe level.