Ultra-low power Ka-band phase noise optimized LCVCO with enhanced FOM of −197.300 dBc/Hz

The NMOS cross-coupled LC Voltage-Controlled Oscillator (LCVCO) is considered an indispensable element in modern wireless communication systems. This research explores the design and implementation of a cross-coupled NMOS LCVCO using the UMC 65 nm CMOS process. The primary objective of this work is to achieve low Phase Noise for ka-band frequency applications with less power consumption. This article proposes Thermal and High frequency noise suppressed LCVCO (TH-LCVCO) technique. The TH-LCVCO technique incorporates a parallel capacitive filter to get rid of thermal noise at high frequencies and an LC tail filter to reduce the second-order harmonics. These techniques help to achieve low phase noise in all 16 tuning bands. The proposed TH-LCVCO technique consumes only 3.29 mW of power, achieving a frequency span from 32.17 GHz to 35.55 GHz with a Phase Noise of -112.6 dBc/Hz at 1 MHz and an Figure of Merit (FoM) of -197.300 dBc/Hz. • The NMOS cross-coupled LC-VCO is crucial for modern wireless communication systems. • This study designs a cross-coupled NMOS LCVCO using the UMC 65 nm CMOS process. • The TH-LCVCO technique suppresses thermal noise and second-order harmonics with parallel and LC tail filters. • The design achieves a frequency span of 32.17–35.55 GHz with -112.6 dBc/Hz Phase Noise. • The proposed LCVCO consumes only 3.29 mW, offering high efficiency for ka-band applications.