Over the last few years, the radio frequency (RF) technology has experienced an exponential growth. With the requirement for more integration, new RF wireless architectures are needed. One of the most critical blocks in a wireless transceiver is the oscillator. Phase noise from radio frequency (RF) oscillators is one of the major limiting factors affecting wireless transceiver performance. Phase noise directly affects short-term frequency stability, Bit-Error-Rate (BER), and phase-locked loop adjacent-channel interference.