Patent ID: 6744807
Filing Date: 2004-06-01
Classification: H04B,H04J,H04L

Abstract:
A multi-dimensional spread spectrum modulator comprising:a spreading sequence generator for generating a set of substantially mutually orthogonal spreading sequences; a first frequency spreading means comprising a first input for a first set of parallel input data streams; a second input for the set of spreading sequences, respective input data streams being associated with respective spreading sequences in the set of spreading sequences; and an output; a second frequency spreading means comprising a first input for a second set of parallel input data streams; a second input for the set of spreading sequences, respective input data streams being associated with respective spreading sequences in the set of spreading sequences; and an output; and a quadrature modulator comprising first and second inputs and an output, the first input of the quadrature modulator being connected to the output of the first frequency spreading means and the second input of the quadrature modulator being connected to the output of the second frequency spreading means, wherein the set of spreading sequences are derived from at least one complex sequence comprising a real part and an imaginary part, wherein each spreading sequence in the set of spreading sequences comprises a combination of at least two parts of the at least one complex sequence, wherein the combination is an arithmetic sum of the real part and the imaginary part, and wherein a first spreading sequence in the set comprises the sum of the real part and a negative of the imaginary part of the complex sequence and wherein a second spreading sequence in the set comprises a negative sum of said real part and said imaginary part of the complex sequence.