A Wavelet-Based Multiple-Access Spread Spectrum Modulation Scheme

A multiple access communication scheme using wavelet-based orthogonal codes is described. The message bit stream in each channel is encoded as a sequence of time-shifted replicates of a mother wavelet symbol at a particular scale. Different channels use the same wavelet symbol but a different scale. The messages are decodable if the time-shifted and dilated replicates of the wavelet symbol used in the encoding are orthogonal. Variations and potential applications of this scale-division multiple access scheme in low probability of exploitation communication systems are discussed. An example is presented to demonstrate the (Fourier) spectral spreading that can be obtained using this approach.