Patent ID: 8218427

Claim:
A method of configuring a preamble for synchronization and channel estimation in a wireless local area network system, the preamble comprising a first preamble and a second preamble, the method comprising: a) arranging the first preamble, used for time and frequency synchronization in a receiver, at starting points of an uplink burst and a downlink burst, wherein arranging the first preamble comprises: arranging, within a data symbol period, 16 S symbols in the starting points of the uplink burst and the downlink burst, and arranging an IS symbol after the 16 S symbols, wherein the IS symbol has a length of a predetermined guard interval and is 180°-phased with respect to the S symbols; and b) arranging the second preamble, used for fine frequency offset estimation and channel estimation in the receiver, after the first preamble, wherein arranging the second preamble comprises arranging two L symbols after the first preamble, wherein a frequency domain signal SPk of the first preamble is given as the following Equation: SP k = { 200 / 24 × ( C 1 , m + 1 4 + j ⁢ ⁢ C 8 , m + 1 4 ) , k = 16 × m , 0 ≤ m < 6 200 / 24 × ( C 1 , m + 1 4 + jC 8 , m + 1 4 ) , k = 16 × ( m + 1 ) + 4 , 6 ≤ m ≤ 11 0 , otherwise where √{square root over (200/24)} is a normalized power value resulted from using 12 sub-carriers among 200 sub-carriers C s,m+1 4 is calculated by inverting 0 into −1 in a matrix generated by an m-sequence generator of a fourth degree polynomial x 4 +x+1, and s is an initial value.