SYSTEM AND METHOD FOR EFFICIENTLY PERFORMING IFFT AND FFT FOR ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING (OFDM) COMMUNICATIONS SIGNALS

摘要

A system communicates data and includes a transmitter for transmitting a communications signal that carries communications data. It includes an efficient modulator (100) for approximating the sine/cosine basis waveforms using complex exponential functions and adding and subtracting the complex exponential functions to generate an Orthogonal Frequency Division Multiplexed (OFDM) communications signal as a plurality of N data subcarriers that carry communications data. A receiver receives the OFDM communications signal and includes a demodulation circuit for demodulating the OFDM communications signal using logical shifts of multiples +/-2P based on the complex exponential functions corresponding to the sine/cosine basis waveform approximations to extract amplitude and phase values from a plurality of N data subcarriers within the OFDM communications signal.