A 56.6-63.1GHz LO generator with a low PN VCO and an ILFT

Abstract

ABSTRACT In this paper, we propose an mm-wave local oscillator generation (LOG) method based on a voltage-controlled oscillator (VCO) with low phase noise (PN) and a novel injection-locked frequency tripler (ILFT), which can significantly improve the PN performance and power efficiency. The VCO features the source-to-gate feedback architecture with a third-impedance enhancement transformer so that the fundamental signal with the boosted third-harmonic output voltage in the source terminal is delivered to ILFT and the relatively pure 20-GHz signal from the gate node can be fed back to the phase-locked loop (PLL). The proposed ILFT adopts the high-order transformer-based resonator, injection-current-boosting (ICB), and class-D tail-switching techniques leading to a wide locking range (LR). Designed and simulated in 40-nm CMOS technology, the post-simulation results exhibit 1-MHz offset PN of better than −102 dBc/Hz over a continuous frequency tuning range (FTR) of 10.9% from 56.6 to 63.1 GHz while consuming 23.5 mW. The figure-of-merit (FoM) achieves up to 186.2 dBc/Hz at 1-MHz offset.