A Fully On-Chip Frequency-Stabilization Mechanism for Terahertz Sources Eliminating Frequency Reference and Dividers

Terahertz (THz) sources with stabilized output frequencies are desired in many systems, however, the design of conventional THz phase-locked loops encounters many challenges. In this paper, a fully on-chip frequency-stabilization feedback mechanism is proposed, which avoids the use of both frequency dividers and the off-chip reference, achieving much lower power consumption and system integration cost. Using this scheme, two circuit prototypes are designed in a 0.13-μm SiGe BiCMOS technology. The first one is a 302-332-GHz frequencystabilized source with ultralow power consumption. It achieves a -13.9-dBm probed output power with a dc power consumption of only 51.7 mW. The second design is a 308-317-GHz frequency-stabilized high-output-power radiating array, which achieves a peak-radiated power and EIRP of 4.6 mW and 24.7 dBm, respectively, with a total dc power consumption of 1.18 W. With significantly lower system integration cost and power consumption, the proposed scheme is attractive for many applications that require short coherence time, such as THz active imaging systems and short-range millimeter-wave (mm-wave)/THz FMCW radars. With further calibration and enhancement in long-term stability, this scheme will also be useful in systems like communication transceivers.