초록 ▼

A method of demultiplexing OFDM signals and a receiver for such signals. More particularly the method is concerned with synchronization in an OFDM receiver. A signal is read into a synchronization unit, in the time domain, i.e., before fourier transforming the signal by means of an FFT processor. In

A method of demultiplexing OFDM signals and a receiver for such signals. More particularly the method is concerned with synchronization in an OFDM receiver. A signal is read into a synchronization unit, in the time domain, i.e., before fourier transforming the signal by means of an FFT processor. In the synchronization unit, a frame clock is derived for triggering the start of the FFT process and for controlling the rate at which data is supplied to the FFT processor. For OFDM reception, it is vital that the FFT process commences at the right point in time. Once the frame clock has been recovered, a frequency error can be estimated by the synchronization unit. The frequency error is used to control; an oscillator which generates a complex rotating vector which is, in turn, multiplied with the signal to compensate for frequency errors. The method can be used both with OFDM systems in which symbols are separated by guard spaces, and with OFDM systems in which symbols are pulse shaped.

대표청구항 ▼

[ What is claimed as new and desired to be secured by Letters Patent of the United States is:] [11.] An OFDM receiver, arranged to demultiplex an OFDM signal, said OFDM receiver comprising:an A/D convertor for digitizing said OFDM signal,synchronization means for performing a cross-correlation of sa

[ What is claimed as new and desired to be secured by Letters Patent of the United States is:] [11.] An OFDM receiver, arranged to demultiplex an OFDM signal, said OFDM receiver comprising:an A/D convertor for digitizing said OFDM signal,synchronization means for performing a cross-correlation of said OFDM signal and for outputting a frame clock,a phase locked loop for producing a synchronized digitized OFDM signal, anda FFT processor, arranged to receive said synchronized digitized OFDM signal based on said frame clock and to demultiplex said synchronized digitized OFDM signal based on said frame clock.