300-335 GHz Highly Efficient Beam-Steerable Radiator Based on Tunable Boundary Conditions

This paper presents a 299.4 GHz–335 GHz highly efficient beam-steerable radiator based on tunable boundary conditions. By controlling the states of switches, the equivalent boundary condition for the radiator is changed, enabling beam steering. The output of the harmonic voltage control oscillator (VCO) is boosted through two-dimensional harmonic boosting technique. The radiator is implemented in 130-nm SiGe BiCMOS process. It enables 20° scan ranges in the
$E$
-plane and 28° scan ranges in the
$H$
-plane. With/without lens, it achieves an equivalent isotropic radiated power (EIRP) of 20.8 dBm/2.4 dBm, 0.8 dBm/-2.6 dBm radiation power, 2.24%/1.02% DC-to-RF efficiency, and a competitive tuning-range of 11.2% for 1.7 V supply.