Patent ID: 6625174
Filing Date: 2003-09-23
Classification: H04B,H04L

Abstract:
A process for transmitting data in packets, the packets comprising a header at a first carrier frequency, followed by an information field at a second carrier frequency, a start of transmission of the information field being tied to a start of transmission of the header of the corresponding packet, comprising:using N distinct and simultaneous subcarriers for transmission in the information field, where N is an integer greater than 1; splitting the data to be transmitted in the information field into successive groups of N symbols; assigning the N symbols respectively to the N subcarriers by OFDM multiplexing; modulating the N subcarriers respectively by the N symbols thereby obtaining a modulating signal made of the N subcarriers; generating a signal at the second carrier frequency varying over time according to a linear ramp for optimizing bandwidth use; modulating the signal at the second carrier frequency by the modulating signal; and mixing the signal, upon reception, corresponding to the information field with a ramp signal corresponding to the signal at the second carrier frequency to obtain a signal corresponding to the modulating signal and to extract from the signal data of the information field.