Patent ID: 7564927

Claim:
A band averaging circuit applied in a multi-band multi-carrier communication system, a packet of the multi-band multi-carrier communication system transmitted via a plurality of carriers, each carrier having a center frequency, and the band averaging circuit utilized for generating a carrier frequency offset of each carrier; the band averaging circuit comprising: a frequency offset estimation unit for generating a plurality of carrier frequency offset ratios corresponding to the plurality of carriers according to a received packet; and a frequency offset adjustment circuit coupled to the frequency offset estimation unit for calculating a weighted average carrier frequency offset ratio according to the carrier frequency offset ratios and comparison results between the carrier frequency offset ratios, and also for calculating the carrier frequency offset of each carrier according to the weighted average carrier frequency offset ratio and the center frequency of each carrier; wherein the frequency offset adjustment circuit comprises: a difference computing unit for calculating a plurality of difference values between each two of the carrier frequency offset ratios; a frequency offset computation module coupled to the difference computing unit for calculating a plurality of weight values according to the plurality of difference values, and for calculating the weighted average carrier frequency offset ratio according to the weight values and the carrier frequency offset ratios, wherein each of the weight values corresponds to each of the carrier frequency offset ratios; and a computing unit coupled to the frequency offset computation module for determining the carrier frequency offset of each carrier according to the weighted average carrier frequency offset ratio and the center frequency of the carrier.