Low phase noise highly power efficient oscillators

The phase noise in oscillators is inversely proportional to the power dissipated in the oscillator. For requirements where low phase noise and low DC power consumption are critical, as is often the case in many mobile communications systems, it is important to design low phase noise oscillators using highly power efficient (possibly switching) amplifiers to obtain minimum noise for minimum DC input power. This also offers the possibility of direct transmission from a phase locked power oscillator