Phased Array Featuring Independent, Simultaneous Beamsteering for Widely Separated mmWave Dual-Band Using Compact, Low-Loss, Selective Coupler

This article introduces a new concept of a phased array that can independently and simultaneously perform beamsteering across two frequency ranges: a lower band encompassing 24 GHz and a higher band including 48 GHz. This concept is exemplified for millimeter-wave (mmWave) applications. The overall structure is realized in conjunction with a newly devised compact, low-loss, selective coupler (CLSC) feed network. The peak realized gain of the exemplified
$1\times4$
antenna array is 9.2 dBi at 24 GHz (fundamental frequency) and 12.2 dBi at 48 GHz (second harmonic), respectively, with a scanning angle of ±45° at both frequencies. To the best of the authors’ knowledge, this work is the first to contribute to the realization of phased arrays that simultaneously operate for widely separated mmWave dual-band.