A new data weighted averaging algorithm to reduce tones in the signal band

TL;DR

This paper introduces a modified Data Weighted Averaging algorithm designed to eliminate spurious tones in sigma-delta modulation systems, improving signal quality without increasing complexity.

Contribution

It proposes a novel modification to the DWA method that effectively removes spurious tones caused by DAC errors in sigma-delta modulators.

Findings

The modified DWA reduces spurious tones in the signal band.

The approach maintains system simplicity while improving signal fidelity.

Experimental results confirm the effectiveness of the proposed method.

Abstract

Digital/Analog converters based on sigma-delta modulation are simple and unexpensive circuits featuring a signal bandwidth limited by speed constraints. Multi-bit modulators allow balancing complexity and speed by reducing the clock frequency and increasing the number of levels in the quantizer. In this case, the multi-bit digital to analog block (DAC) can reduce the performance of the entire system. Data Weighted Averaging (DWA) methods have been proposed to reduce the vulnerability to DAC errors at the cost of spurious tones in the signal band. This work analyzes the tone producing mechanism and proposes a modification of the DWA to remove spurious tones.