Patent ID: 7940867

Claim:
A method for correlating scattered pilot locations in a sequence of orthogonal-frequency-division-multiplexing (OFDM) symbols transmitted by a transmitter and received by a receiver in a multi-carrier transmission system, said OFDM symbols comprising continuous pilot symbols and scattered pilot symbols, said method comprising: mapping pilot locations comprising pilot symbols having predetermined known values, wherein said pilot symbols are positioned among data subcarriers in time and frequency dimensions consisting of received pilot symbols and having a predetermined position pattern in said time and frequency dimensions, wherein said predetermined position pattern comprises a finite number of sub-position patterns each corresponding to positions of said pilot symbols; estimating a Doppler spread in a frequency spectrum between said transmitter and said receiver in said multi-carrier transmission system; estimating a channel length of a set of channel paths received at said receiver; providing a predetermined method of correlating said scattered pilot locations in said sequence of OFDM symbols; and said receiver automatically selecting said predetermined method of correlating said scattered pilot locations in said sequence of OFDM symbols based only on the estimating processes, wherein the selecting process comprises: grouping a range of all occurrences of the same pilot symbol located across multiple subcarriers corresponding to a single time dimension and multiple frequency dimensions, wherein said range comprises all occurrences of the same pilot symbol located between and including a first received scattered pilot symbol and a second received scattered pilot symbol received across multiple subcarriers; creating a graphical pilot correlation sequence corresponding to the grouped range of all occurrences of the same pilot symbol located across multiple subcarriers; locating peaks in said pilot correlation sequence; and identifying said peaks as scattered pilot symbol locations.