Silicon Laboratories Inc.
WLAN Receiver Early Powerdown based on Center Frequency Offset Detection

Abstract:

A wireless local area network (WLAN) station receiver has a center frequency offset (CFO) estimator and an CFO table with an association between a CFO value from a recently received access point packet for which the station is associated according to 802.11. The receiver performs a comparison between the CFO estimate of the received packet and the CFO value from the CFO database, and powers the receiver down if the comparison exceeds a threshold. The threshold may be an absolute value in parts per million, or may include a time drift compensation component.