Sub-mm-Wave and terahertz frequencies have many applications such as medical imaging, spectroscopy and communication systems. CMOS signal generation at this frequency range is a major challenge due to the limited cut-off frequency of transistors and their low breakdown voltage. A recent work has demonstrated generation of high power at a fixed frequency in the sub-mmWave range using a harmonic oscillator [1]. However, for most applications a tunable signal source is necessary. In previous works, frequency multipliers are used as an alternative for tunable power generation above 150GHz [2]. In this work, for the first time we introduce a tunable high-power oscillator at sub-mmWave frequencies in low-power (LP) bulk CMOS. There is a tradeoff between power generation and tuning range in high-frequency VCOs. This is primarily because the quality factor of tuning varactors decreases rapidly with frequency. Therefore, tuning frequency with varactors results in
Yahya M. Tousi, Omeed Momeni, Ehsan Afshari
Cornell University, Ithaca, NY