Many-carrier signal and transmission and reception thereof

摘要

An OFDM signal having a large plurality of data-bearing carriers (80;84) spaced by a predetermined spacing includes a plurality of pilot carriers (82;86). Each pilot carrier is spaced from the nearest data-bearing carrier and the other pilot carriers by not less than a multiple of the predetermined spacing, the multiple being at least two. A receiver for the OFDM signal includes a receiver and demodulator section (12-30) for receiving and demodulating the OFDM signal to provide a plurality of data carriers and a plurality of pilot carriers; a phase detecting section (40) for detecting phase error in the pilot carriers; a phase compensating circuit (38) for phase compensating the data carriers in dependence upon pilot carrier phase; and a main Fourier transform circuit (32) connected to the output of the phase compensating circuit. The phase compensating circuit includes a second Fourier transform circuit which provides a number of points which is a sub-multiple of the number of points provided by the main Fourier transform circuit, this sub-multiple being at least two.