A CMOS highly linear hybrid current/voltage controlled oscillator for wideband polar modulation

Abstract

A highly linear oscillator is presented for wideband polar modulation. It has both a varactor voltage tuning input for frequency locking and temperature compensation of phase locked loop (PLL) as well as an inductive current tuning input for linear phase modulation of PLL. Implemented in 65 nm CMOS technology, it achieved a frequency tuning gain variation of less than ±2% over more than 32 MHz frequency range meeting the WCDMA polar modulation requirement. At 3.8 GHz and 3 MHz offset, its phase noise is -136.5 dBc/Hz with current consumption of 18 mA from 2.1 V supply.