Patent ID: 7489731

Claim:
A method of communicating over a wireless network using OFDM communication system comprising the steps of: in each transmitter, providing a stream of data, arranging the data into packets, appending a pilot symbol comprising a repeated pseudo random binary sequence to the start of each data packet, multiplexing the packets to convert the data from serial to parallel, performing an inverse fast Fourier transform on the data to convert the multiplexed data from the frequency domain to the time domain, sampling the data at a rate greater than the nominal data rate, digitally low pass filtering the data, converting the data from the digital data to analogue data, and using the data to modulate an RF carrier thereby frequency shifting the data to a higher frequency band for transmission, in each receiver, demodulating an RF carrier from the received data thereby shifting the date to baseband, converting the demodulated analogue signal into a stream of digital data at an oversampled data rate, digitally low pass filtering the digital data to remove out of band noise, down-sampling (decimating) the filtered data to the nominal sample rate, detecting the start packet of the down-sampled data by searching for significant correlations within the pilot symbol within the data stream, making an estimate of at least one signal parameter, removing the estimated frequency-offset and phase-offset using a digital phase locked loop, transforming the data using a fast Fourier transform from time domain data to frequency domain data, removing the estimated sub-sample timing offset from the transformed data using a linear phase shifter, assigning each bit of the transformed data to an allowable data point to produce noise free data, and demultiplexing the noise free data from parallel data to serial data.