Design of D-band G$_{max}$-based CMOS low noise amplifier for B5G/6G communication

Abstract

This thesis proposes single-ended and single-ended to differential low-noise amplifiers (LNAs) operating in the 150 GHz band. This thesis newly proposes a pseudo-simultaneous noise and input matched (p-SNIM) G$_{max}$ core for a high gain, wideband, and low power LNA. In addition to the SNIM G$_{max}$ technology, in which SNIM is applicable only to a single frequency, a p-SNIM G$_{max}$ , which can apply approximate SNIM with only a 0.5 dB level difference in wideband, has been proposed. The proposed technique is applied by increasing the conductance value required for conjugate matching through the boosting of the stability factor (Kf ) of the G$_{max}$-core. The measurement results show a maximum gain of 16.3 dB at 148 GHz, a 3-dB bandwidth of 23 GHz, and a noise figure of 4.9 dB. The fabricated LNA achieves the highest FoM among other reported CMOS-based D-band LNAs. This thesis proposes a new differential dual-peak G$_{max}$-core based on coupled transmission lines to resolve the problem of existing single-ended topology. Unlike the single-ended G$_{max}$-core that required a transmission line longer than the quarter wavelength, a newly proposed differential G$_{max}$-core can be implemented with a much smaller area by adopting a coupled transmission line. To suppress the loss component of the balun, which is essential by adopting a differential mode, a single-ended to differential mode topology is adopted in which a single-ended amplifier is placed at the first stage. That single-ended amplifier is implemented based on lumped elements with a much smaller area.