Characterization of Phase and Amplitude Quantization Effects in a Direct Digital Synthesis-based Waveform Generator for Future Software-Defined GPS Payloads

This paper describes a software-defined GPS signal generator with a direct digital synthesis (DDS) architecture to examine the effects of quantization on a signal. We explore the power and cardinality of spurious frequency components due to phase and amplitude quantization on the generated signal. MATLAB® models are developed to match the hardware that is implemented in a field programmable gate array (FPGA) with a high speed digital-to-analog converter (DAC). Once the MATLAB model is validated against hardware, it is used to determine the optimal phase and amplitude resolution for given implementation.