Search

This article presents a fully integrated quadrature cross-coupled voltage controlled oscillator (QVCO) using common-drain transistor instead of common-source transistor as a coupling device.The prototype 3.8 GHz QVCO in 0.18 μm CMOS process is proposed to generate four output phases and it uses two p-core cross-coupled VCOs and nMOS coupling devices. The proposed QVCO oscillates from 3.6 to 3.84 GHz and the power consumption is 7.24 mW at 0.74 V supply voltage. The measured phase noise is -126.19 dBc/Hz at 1 MHz offset frequency from the carrier frequency 3.745 GHz. The VCO occupies a chip area of 1.08 ×0.924 mm2 and provides a figure of merit of -189.05 dBc/Hz. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1262-1266, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27578 [ABSTRACT FROM AUTHOR]

This letter proposes a dual-band divide-by-2 transformer-coupled quadrature injection-locked frequency divider (QILFD).The QILFD is composed of a transformer-coupled quadrature voltage controlled oscillator and two injection MOSFETs. The CMOS QILFD has been implemented with the Taiwan Semiconductor Manufacture Company (TSMC) 0.18 μm CMOS technology, and the core power consumption is 3.997 mW at the supply voltage of 0.7 V. The tank impedance of the QILFD shows a dual resonance behavior, which leads to a dual-band locking range at a fixed bias condition. At the injection input power of 3 dBm, the low-band and high-band divide-by-2 locking ranges are from 6.90 to 8.56 GHz and 9.52 to 12.10 GHz, respectively. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26074 [ABSTRACT FROM AUTHOR]