Millimeter-Wave and Sub-Terahertz Parametric Harmonic Generation

Abstract

The theory of parametric harmonic generation is described in this thesis. It is shown that for Nth-order harmonic generation the time-varying parameter (P), such as elastance (S), capacitance (C), conductance (G), or resistance (R), exhibits N−1 periods of a sine wave under one sinusoidal pumping cycle, which is named sinusoidal representation of pumped parameters. The maximum conversion efficiency of reactive frequency multipliers is 1/N. The related P-V curves are described by the Chebyshev polynomials. Impulse representation of pumped parameters is also developed to represent a transient train of pulses to describe the resistive multipliers. Several circuits are designed to demonstrate the validity of the theory and explore the parametric circuits in millimeter-wave and sub-THz bands. A frequency tripler is designed in the 28-GHz 5G band, using the topology of symmetric antiparallel pair of series varactors to achieve about 24-dB conversion loss (CL), −8-dBm maximum output power (POUT), and 18% relative bandwidth (BW). Two reconfigurable frequency multipliers (RFMs) are designed based on antiparallel nMOS-varactor pairs (APNVP) and switched-capacitor varactor (SCV) pairs. The SCV can obtain the ratio of maximum-to-minimum capacitance as high as 20, almost 10 times better than that of MOS varactors. The SCV-based RFM demonstrates much better performance than the APNVP-based RFM. A resistive tripler based on an antiparallel diode-connected nMOS transistor pair is also designed and measured in the D-band, with wide 28% BW and −16 dBm POUT. The CL can be improved by increasing the non-linearity of the resistance by tuning the back-gate control voltage. A voltage-controlled inductor is proposed based on a transistor-controlled capacitor and demonstrated in a D-band injection-locked oscillator with a ≥16% tunable operating frequency range, dc power as low as 5.6 mW, and a compact 0.018-square-mm core size.