VCO utilising bilaterally coupled transformer-based resonator

The bilateral transformer coupling technique is proposed to improve the phase noise of the transformer-based voltage controlled oscillator (VCO). Current-reuse and self-injection locking techniques are also included and demonstrated in CMOS 0.18 μm technology. The oscillation frequency ranges from 5.02 to 5.41 GHz. The output power is - 1.2 dBm, the phase noise at 1 MHz offset frequency is - 128 dBc/ Hz and the chip size is 0.478 mm2. The power consumption is 3.6 mW. The figure-of-merit of this oscillator is - 197.