A 5-GHz low-phase-noise CMOS LC-VCO for China ETC applications

A 5-GHz fully integrated for China ETC applications, low-phase-noise and wide-band LC voltage controlled oscillator is presented. Low-phase-noise has been achieved by using control line filtering technology and avoiding the tail current source. The circuit is implemented in the 0.18um TSMC CMOS process. The oscillator is tuned from 5.27 to 6.41 GHz with switched capacitors. This VCO consumes 5.6mA from a 1.8V supply and features a phase noise of -117 dBc/Hz at 1 MHz frequency offset.