Patent ID: 8160165
Filing Date: 2012-04-17
Classification: H04L

Abstract:
1. A communications device, comprising: a source of communications data and a training sequence corresponding to a preamble; a modulation and mapping circuit that modulates the communications data and training sequence into a plurality of multiple subcarriers that are orthogonal to each other to form an Orthogonal Frequency Division Multiplexing (OFDM) communications signal having modulated subcarriers carrying the communications data forming a data payload and modulated subcarriers forming the preamble; a pseudo-random signal generator operative with the modulation and mapping circuit and configured to generate pseudo-random signals to the modulation and mapping circuit based on an encryption algorithm to frequency hop each subcarrier at an OFDM symbol rate and turn ON and OFF selected subcarriers; and wherein said modulation and mapping circuit is configured to apply a quadratic modulation to each of the subcarriers carrying the training sequences and apply a specific phase angle to each sinusoid forming the modulated subcarrier carrying the training sequence to produce a low peak-to-average power ratio (PAPR) preamble.