Damping shift keying (Dsk): A new modulation space for single carrier communications

While the amplitude, frequency and phase, are the well-known carrier features that can be modulated according to digital data stream, there is still another unexploited sinusoidal feature. Sinusoidal damping factor is the suggested modulation technique that can be used in carrier communication. In this paper, damping shift keying (DSK) is proposed as a new modulation space that can be combined with conventional modulation techniques to increase the data rate per symbol. In addition to the complex amplitude modulation, the carrier can be modulated using multi-damping factors according to the data stream. Combination of DSK with quadrature amplitude modulation (QAM) increases the data rate of the so called Damped QAM (D-QAM). Simulation results measures the performance of the proposed D-4PSK (carrying 3 bits/symbol) against conventional QPSK (carrying 2 bits/symbol). The proposed scheme exhibits nearly the same bit-error-rate (BER) performance but with 50% increase in the data rate. Moreover, in this paper all-feature shift-keying (ALFSK) schemes will be defined which allows modulating of all sinusoidal features (amplitude, phase, frequency and damping factor) simultaneously.