Design of a Voltage-Controlled Oscillator for Ka-Band Applications

Abstract

A varactor-less cross-coupled voltage-controlled oscillator based on triple frequency is presented in this paper, which is optimized for a low phase noise and low power at high frequency. The VCO consists of voltage to current, a triple frequency, and a mixer with band-pass filter. The varactor-less VCO adjusts the frequency with the current and voltage of transconductance cell. A network R_F–C_F–R_F is applied to filter out the noise of current source at 2${\omega }_0$. The proposed circuit was simulated in a 0.18 µm CMOS RF technology with a 1.5 V supply voltage. The designed VCO demonstrates an oscillation frequency range from 11.59 to 13.96 GHz with the triple frequency from 35.8 to 40.3 GHz. The simulated VCO presents a phase noise of −110.1 dBc/Hz at 1 MHz offset from a 40.3 GHz carrier frequency. The total figure of merit (FOM_T) is −193.113 and −190.83 dBc/Hz with a DC power of 11.32 and 19.56 mW for VCO and total structure, respectively. The layout of the VCO occupies an area of 695.10 µm $\times$627.80 µm.

KEYWORDS:

• Oscillation frequency
• Phase noise
• Triple frequency
• Tuning range
• VCO

Additional information

Notes on contributors

Abbas Nasri

Abbas Nasri was born in Qazvin in 1991. He received a degree in electronics engineering from Zanjan University (ZNU), Iran in 2015. He is currently working toward his PhD degree at the University of Zanjan. He has worked with the DET group of the Politecnico di Torino in the Microelectronics-Integrated Circuits Lab. His research interests include RF and microwave integrated circuits. Email: [email protected]

Mostafa Yargholi

Mostafa Yargholi received the BSc degree in communication engineering from Iran University of Science and Technology (IUST), Iran in 2002, and the MSc and PhD degrees in electronics engineering from Tarbiat Modares University (TMU), Iran in 2004 and 2009, respectively. He has been working as an associate professor with the Department of Electrical Engineering, University of Zanjan, since 2009. His current research interests include designing of RF integrated circuits, UWB systems, data converters, and CMOS integrated circuits. Corresponding author. Email: [email protected]