Adaptive Intra-Symbol SMSE Waveform Design Amidst Coexistent Primary Users

An analytic approach is presented for optimizing spectrally modulated, spectrally encoded (SMSE) waveforms using independent selection of intra-symbol (within a symbol) subcarrier power and modulation order. The SMSE framework is well-suited for cognition-based, software defined radio (SDR) applications. By exploiting statistical knowledge about the spectral and temporal behavior of interfering signals, the inherent SMSE framework flexibility is leveraged to substantially increase system throughput while limiting coexistent interference. Results for a coexistent scenario are provided in which the analytic optimization of the SMSE waveform is demonstrated in the presence of multiple direct sequence spread spectrum (DSSS) signals. The results reveal significant performance benefits that demonstrate the potential of the SMSE framework to dynamically adapt to changing environmental conditions-key functionality required for future SDR implementations.