Patent ID: 7558245
Filing Date: 2009-07-07
Classification: H04L

Abstract:
1. An orthogonal frequency division multiplexing (OFDM) communication device, comprising: an OFDM receiver for receiving an OFDM signal containing a multitone synchronization signal; a synchronization interval sampler for receiving said OFDM signal and producing a sequence of samples therefrom; an initial time and frequency offset estimator coupled to said synchronization sampler for producing from said sequence of samples a time offset estimate and an initial frequency offset estimate, said time offset estimate being supplied to said receiver; and a frequency offset estimate refinement unit coupled to said sampler and said estimator, said frequency offset estimate refinement unit receiving a reference multitone synchronization signal in addition to said sequence of samples and said initial frequency offset estimate and producing therefrom an improved frequency offset which is supplied to said receiver.