Patent ID: 6115354
Filing Date: 2000-09-05
Classification: H04H,H04L

Abstract:
An apparatus used in a transmitter and/or receiver for multiple carrier modulated (OFDM modulated) digitally coded data,comprising at the transmitter side:means for generating a time sequence of OFDM symbols;means for patterning said generated OFDM symbols into successive OFDM transmission frames, with each OFDM transmission frame being comprised of a frame head with one or several control symbols and an information data range with a plurality of data symbols, and with guard intervals preceding said data symbols; andcomprising at the receiver side:means for extracting said data symbols and said control symbols from the received OFDM symbols;means for synchronizing the received OFDM symbols in response to the time length of said guard intervals;whereina predetermined means provided at the transmitter side and at the receiver side for selecting in each OFDM transmission frame the time length of the guard intervals for said symbols to be shorter than the time length of the guard intervals for said control symbols.