Systems and Methods for Digital Signal Synthesis with Variable Sample Rate DAC

Abstract

Systems and methods for digital signal synthesis with variable sample rate digital-to-analog converters (DACs) in accordance with embodiments of the invention are described. One embodiment includes a digital frequency generator that includes a direct digital frequency synthesizer (DDFS); a digital-to-analog converter (DAC); a frequency/phase estimation circuit; a stable reference clock (REF CLK); a variable frequency sample clock; a frequency control word (FCW); where the DAC is sampled by the variable frequency sample clock; where the DDFS is clocked by the variable frequency sample clock; where the frequency/phase estimation circuit receives a the stable REF CLK and the variable frequency sample clock and estimates a FCW frequency error and adjusts the FCW to the DDFS; where the DDFS receives the FCW and outputs a digital sine codeword at the variable frequency sample clock to the DAC, where the FCW is continuously adjusted to track the variable frequency sample clock.

Dependencies are inferred from the claim text.