An Analog Modulation Using a Spiral Mapping

This work presents the spiral analog modulation, which is a mapping scheme for continuous in value discrete in time samples based on the spiral locus S (x) = xeix. A mapping function is used to map the source onto the spiral. The Maximum Likelihood (M.L.) optimal demodulator is presented followed by approximated demodulators. The SNR gain and the threshold SNR are analyzed and simulated. Finally we optimize classes of mapping functions with regard to maximum SNR for a given threshold SNR.