Design of A 28-GHz CMOS Reconfigurable Dual-Function Switch Network

This paper presents a 28-GHz reconfigurable switch for millimeter-wave beamforming applications, which can be reconfigured with two functionalities, serving as a single-pole double-throw (SPDT) switch or an equal power dividing mode (PD). In the SPDT switch mode, the measured insertion and return losses are <6.4 dB and >7 dB, respectively, and the isolation is >20 dB in 26.5-29.5 GHz band. The input P
1dB
is 20 dBm at 28 GHz. For the PD mode, the measured isolation is better than 17 dB with an insertion loss of 9.6 dB from 26.5 to 29.5 GHz. This circuit was realized in 90-nm CMOS technology with a chip size of 0.58×0.60 mm
²
(excluding the I/O pads) and zero power consumption.