This paper presents a low-noise class-F23voltage-controlled oscillator (VCO) with harmonic resonance expansion and$2^{\mathrm {nd}}$/$3^{\mathrm {rd}}$-harmonic outputs for multiband mm-wave applications. By using a single four-coil transformer to extend the common-mode (CM) and differential-mode (DM) harmonic resonance bandwidths, the$2^{\mathrm {nd}}$- and$3^{\mathrm {rd}}$-harmonic resonances can be acquired without additional frequency alignment calibration. Meanwhile, benefiting from the favorable differential response at the$2^{\mathrm {nd}}$- and$3^{\mathrm {rd}}$-harmonic frequencies, the corresponding harmonic frequency outputs are extracted, simultaneously. Fabricated in 65-nm CMOS process, the proposed VCO achieves a frequency tuning range (FTR) of 20.8% from 10.71 GHz to 13.20GHz with 1-MHz offset phase noise (PN) from -117.4 to -114.5 dBc/Hz, while consuming 7.8-9.8 mW at 0.6 V. The VCO core area is only 0.054 mm2and the flicker noise corner is 310-450 kHz. The figure-of-merit (FoM) at 10-MHz offset scores 189.8-191.7 dBc/Hz. The harmonic outputs achieve a FTR of 21.42-26.40 GHz and 32.13-39.60 GHz, with a 1-MHz-offset PN from –110.5 to –107.5 dBc/Hz and –107.6 to –104.8 dBc/Hz.

We propose a miniaturized wideband metasurface antenna for 60-GHz antenna-in-package applications. With the glass integrated passive device manufacturing technology, we introduce a coplanar-waveguide-fed (CPW-fed) ring resonator to characterize the material properties of the glass substrate. The proposed antenna is designed on a high dielectric constant glass substrate to achieve antenna miniaturization. Because of the existence of gaps between patch units compared with the conventional rectangular patch in the TM 10 mode, the radiation aperture of this proposed antenna is reduced. Located right above the center feeding CPW-fed bow-tie slot, the metasurface patch is realized, supporting the TM 10 mode and antiphase TM 20 mode simultaneously to improve the bandwidth performance. Using a probe-based antenna measurement setup, the antenna prototype is measured, demonstrating a 10-dB impedance bandwidth from 53.3 to 67 GHz. At 60 GHz, the antenna gain measured is about 5 dBi in the boresight direction with a compact radiation aperture of 0.31 λ ×0.31 λ 0 and a thickness of 0.06 λ 0 .