Patent ID: 8089990

Claim:
An apparatus for preventing a data read error for orthogonal frequency division multiplexing (OFDM) symbol demodulation, comprising: an average time synchronization offset estimating unit estimating average time synchronization offset between a pilot symbol of a time synchronized data frame and pilot symbols of succeeding data frames next to the time synchronized data frame, wherein the time synchronization offset is due to a reference clock frequency difference between a transmitter and a receiver; a data buffer control unit acquiring a start location of a data frame to be read by a data buffer using the estimated average time synchronization offset, and the data buffer control unit controlling the data buffer's reading of the data frame to be read using the acquired start location information of the data frame to be read, wherein the data buffer control unit controls a data pointer in the data buffer, the data pointer indicating a start location of the data frame to be read by the data buffer; and wherein the average time synchronization offset is estimated by Equation, Δ ⁢ ⁢ t F = N 2 ⁢ π ⁢ ⁢ k ⁢ tan - 1 ⁡ ( Y i + F ⁡ ( k ) Y i ⁡ ( k ) ) Equation where, Δt F is average time synchronization offset, Y i (k) is a k-th frequency component of a Discrete Fourier Transform value of an i-th time synchronized pilot symbol, Y i+f (k) is spaced apart from the i-th time synchronized pilot symbol by F pieces, which is a k-th frequency component of a Discrete Fourier Transform value, and N is the number of total sample points included in one OFDM symbol.