Frequency Synthesizer Settling Time and Phase Noise Issues For WLAN Transceiver Application in IEEE 802.11n Standard

Frequency synthesizer design issues for WLAN applications in IEEE 802.11n standard (draft) are proposed in a systematic aspect. A new concept is introduced on effective phase noise traded off with the settling time which is optimized through widening the loop filter band-width. Simulations are carried out through PLL Design Assistant. Expected phase noise and settling behavior of standard are translated to synthesizer. The effects of phase noise on OFDM constellation error is demonstrated by ADS software.