A 312-GHz CMOS Injection-Locked Radiator with Chip-and-Package Distributed Antenna

This paper presents an injected-locked THz radiator integrating a half-quadrature voltage-controlled oscillator (HQVCO), four injection-locked frequency quadruplers (ILFQs), and a chip-and-package distributed antenna (DA). At the system level, an architecture based on injection locking is employed to allow individual optimization of the output power and the phase noise. At the circuit level, intrinsic-delay compensation and harmonic boosting techniques are proposed to optimize the phase noise of the HQVCO and the output power of the ILFQs, respectively. The proposed DA composed of four exciting elements on silicon chip and a primary radiator in low-temperature co-fired ceramic (LTCC) package features a wide bandwidth of 13% and a gain of 3.8 dBi without using lens at 312 GHz. Implemented in a 65-nm CMOS process, the radiator system occupying a core area of 0.36 mm² achieves output frequency from 311.6 to 315.5 GHz and maximum equivalent isotropically radiated power (EIRP) of 10.5 dBm while consuming 300 mW. The output phase noise measures -109.3 dBc/Hz at 10-MHz offset and the dc-to-THz efficiency is 0.42%.