Patent ID: 8446990

Claim:
A carrier frequency offset (CFO) synchronization method of an orthogonal frequency division multiplexing (OFDM) receiver, wherein an OFDM frame comprises a guard interval including pseudo-noise (PN) sequences as a training signal, the CFO synchronization method comprising: step (a1) calculating a CFO estimation value e Λ by widening a CFO tracking range by setting a correlation interval P between a first correlation operation C 1 and a second correlation operation C 2 to be less than a predetermined value in double correlation in which the first correlation operation C 1 and the second correlation operation C 2 are used to calculate the CFO estimation value e Λ , wherein the first correlation operation C 1 is a function of a local copy of the PN sequence and not of the correlation interval P, and wherein the second correlation operation C 2 is a function of the local copy of the PN sequence and of the correlation interval P; step (b1) calculating the CFO estimation value e Λ by narrowing the CFO tracking range by setting the correlation interval P to be greater than the predetermined value in step (a1); and step (c1) calculating the CFO estimation value e Λ using auto-correlation.