Patent ID: 7606138

Claim:
An OFDM receiver for receiving a multi-symbol encapsulated (MSE) OFDM signal transmitted along a transmission channel, said MSE OFDM signal comprising a preamble sequence having a pre-determined structure, the OFDM receiver comprising: an A/D converter for sampling the received OFDM signal at a sampling frequency and for producing a sequence of received waveform samples; a synchronization and channel estimation unit adapted to identify the preamble sequence in the sequence of received waveform samples and to perform channel and frequency offset estimation from the received preamble sequence and the pre-determined structure of the preamble sequence; a cyclic guard removing unit adapted to identify information-bearing OFDM frames in the sequence of received waveform samples, to remove the cyclic guard portions from each identified OFDM frame and to produce a sequence of guard-removed OFDM frames; a channel equalizer, comprising: first processing means adapted to perform at least an M×N points DFT and M×N complex multiplications for converting the guard-removed OFDM frames to frequency domain, and for frequency-domain equalization to produce a sequence of equalized frame spectra; and, second processing means adapted to perform at least an M×N point inverse DFT on each equalized frame spectrum to produce a sequence of equalized guard-less OFDM frames, each comprising M OFDM symbols; third processing means adapted for splitting the equalized frame into M OFDM symbols, performing M N-point inverse DFTs for demodulating the equalized guard-less OFDM frames and for producing a set of M×N received m-ary symbols from each equalized OFDM frame; and, a parallel-to-serial converter adapted to convert the set of M×N received m-ary symbols into a received sequence of m-ary data symbols.