Patent ID: 8155073

Claim:
A wireless communication system including a transmitter for transmitting data using a multipath fading channel and a receiver for receiving them from the transmitter, comprising: a mapper for mapping an externally received binary information sequence to at least one symbol according to the MQAM (M-ary quadrature amplitude modulation) method; a serial to parallel converter for converting the mapped symbols into vector data which are information transmit vectors; a first IDFT (inverse discrete Fourier transform) unit including m IDFT units for performing IDFT on the converted information transmit vectors; an interleaver for writing subchannel values of the respective transmit vectors received from the IDFT unit in an m×n memory buffer in the first direction; a second IDFT unit including n IDFT units for reading the subchannel values written in the first direction in the second direction when the writing in the first direction is finished, performing IDFT on the read subchannel values, and modulating them to OFDM (orthogonal frequency division multiplexing) signals; a third IDFT unit for modulating a pilot symbol vector for predicting an amplitude and a phase of the multipath fading channel to an OFDM signal; and a parallel to serial converter and guard interval inserter for inserting a guard interval into the signal received from the second IDFT unit, converting the guard interval inserted information transmit vector into a serial signal, transmitting the serial signal, converting the guard interval inserted pilot symbol vector into a serial signal, and transmitting it to the transmitter; a guard interval eliminator and serial to parallel converter for eliminating the guard interval from the converted and received serial signal, and converting the guard interval eliminated serial signal into an information transmit vector and a pilot symbol vector respectively; a first DFT unit including M DFT units for demodulating the converted information transmit vector into an OFDM signal; a third DFT unit for demodulating the converted pilot symbol vector into an OFDM signal; a channel predictor and interpolator for predicting the amplitude and phase of the multipath fading channel using the demodulated pilot symbol vector; a channel compensator for compensating the amplitude and phase of the channel multiplied to the demodulated information transmit vector according to the predicted amplitude and phase of the channel; a deinterleaver for writing the compensated channel signals in an M×N memory buffer in the first direction; a second DFT unit including N DFT units for reading the signal with less channel autocorrelations in the second direction from among the channel compensated signals written in the first direction, performing DFT on the read signals, and demodulating them into OFDM signals; a parallel to serial converter for converting the demodulated signals into serial signals; and a decoder for restoring the converted serial signals into a binary information sequence, and outputting the binary information sequence.