Patent ID: 7145955

Claim:
A method of generating and transmitting a preamble signal in an OFDM (Orthogonal Frequency Division Multiplexing) system, comprising the steps of: generating said preamble signal comprising at least a first part, a second part following said first part in the time domain, and a third part following said second part in the time domain, wherein said first part is designed for a frame detection and/or an AGC (automatic gain control), said second part is designed for a coarse timing and frequency synchronization, and said third part is designed for fine synchronization, and wherein each of said first and second parts contains a frequency domain sequence comprising 12 complex symbols mapped on every four subcarriers of all available 52 subcarriers of said ODFM system, and said third part contains 52 symbols, each set to 1 or −1, mapped on said all available 52 subcarriers; generating a time domain signal from said preamble signal by performing an inverse fast Fourier transform (IFFT) on said frequency domain sequences; and transmitting said time domain signal from a transmitter-side to a receiver side of said OFDM system; wherein said 12 complex symbols in the frequency domain sequences of said first and second parts are set so that a synchronization performed in the receiver side includes correlating said frequency domain sequence of said first part and said frequency domain sequence of said second part, and a last six symbols of the first part are each identical to each of respective last six symbols of the second part.