Zero-Order Reconstruction Optimization of Waveforms (ZOROW) for Modest DAC Rates

The use of waveforms possessing constant envelope and good spectral containment, combined with high-fidelity arbitrary waveform generation (AWG) capability, has been shown to minimize transmitter distortion effects when waveform diversity is needed. Software-defined radios (SDRs) represent a lower cost, attritable alternative to AWGs at the price of lower fidelity. Specifically, the lower digital-to-analog conversion (DAC) rates supported by SDRs introduce new design challenges for the generation of waveforms requiring high fidelity, most notably those containing in-band spectral notches. Here these challenges are addressed via the ZOROW waveform design scheme that accounts for physical attributes of the SDR. Distortion effects arising from the modest DAC rate are characterized and their mitigation is demonstrated using experimental measurements.