On-chip GaN-on-SiC VCO using a tunable substrate integrated waveguide loaded with complementary split ring resonator

ABSTRACT

This paper presents an S-band voltage-controlled oscillator (VCO) using a tunable half-mode substrate integrated waveguide (HMSIW) loaded with complementary split ring resonator (CSRR) in GaN-on-SiC high-electron-mobility transistor technology. A varactor connected to the center of the outer conductor of the HMSIW-CSRR changed the effective capacitance, resulting in a resonance frequency shift but a fixed transmission zero. Therefore, the S-band VCO can be tuned by the HMSIW-CSRR using harmonic suppression. The tunable HMSIW-CSRR VCO exhibited a frequency tuning range of 3.55–3.98 GHz with a varactor voltage of 0–6 V. The maximum output power was 21.1 dBm and rf-to-dc efficiency was 12.8% at 3.98 GHz. The lowest phase noise was −117 dBc/Hz with 1-MHz offset at a 3.56 GHz carrier frequency with 30.55 dBc of harmonic suppression.

KEYWORDS:

• Voltage-controlled oscillator
• tunable HMSIW-CSRR
• GaN-on-SiC
• harmonic suppression

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was partially supported by the Ministry of Science and Technology, Taiwan (107-2221-E-182-042) and the Chang Gung Memorial Hospital, Taiwan (BMRP957 & CMRPD2H0311).

Notes on contributors

Hsuan-Ling Kao

Hsuan-Ling Kao received the B.S. degree in Electrical Engineering from Chang-Gung University, Taoyunan, in 1998, the M.S. and Ph. D. degrees in Electronics Engineering from National Chiao Tung University, Hsinchu, Taiwan in 2000 and 2006, respectively. From 2000 to 2006, she joined the Macronix Company, Hsinchu, Taiwan. Since Oct. 2006, she has been with Department of Electronics Engineering, Chang Gung University, Taoyunan, Taiwan, and is currently a Professor. She has authored or co-authored over 80 SCI journal publications. Her current research interests include inkjet printing technology, microwave and millimeter-wave devices and integrated circuits.

Cheng-Lin Cho

Cheng-Lin Cho was born in Taipei, Taiwan. He received the B.S. degree from the Department of Electronic Engineering, National Formosa University, Yunlin, Taiwan, in 2009, and the M.S. degree from the Department of Electronic Engineering, Chang Chung University, Taoyuan, Taiwan in 2013. He is currently pursuing the Ph.D. degree from the Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan. His current research interests include flexible devices. Now he also joined Chang-Gung University, Taoyunan, and is currently a researchers.