Progress Towards Fully On-Chip Frequency-Stabilization for Sub-Terahertz Sources

Abstract

All promising applications of sub-terahertz (sub-THz) and millimeter-wave (mm-wave) systems, from molecular spectroscopy with absolute spectral specificity, high-resolution imaging and sensing, and ultra-high-speed communications, require the design of frequency-stabilized signal generators. In this paper, we review the recent progress made in UNIC group at the University of Michigan, to implement stabilized-frequency signal generators at sub-THz frequencies. First, we report a coherent imaging transceiver at 319–323 GHz, which utilizes a conventional phase-locked loop technique for frequency locking. It achieves radiated power of 2 mW with the total DC power consumption of 605 mW. To eliminate the frequency divider and off-chip reference in the PLL loop, we report another work based on the new idea of on-chip frequency stabilization feedback. It is a 308–317 GHz frequency stabilized high-output-power radiating array with peak-radiated power of 4.6 mW and total DC power consumption of 1.18 W. All of the above circuits are fabricated using 130 nm SiGe:C BiCMOS technology.