Title
Multiplierless Implementation of an Aliasing-Free Digital Pulsewidth Modulator
Abstract
Digital pulsewidth modulators are used to transform nonconstant amplitude signals into pulsed signals, such that the information lying in the signal amplitude is encoded in the widths of pulses. Because of the inherent aliasing distortion in digital pulsewidth-modulated signals, additional signal processing steps are required to make pulsewidth modulation (PWM) suitable for applications like digital audio amplification or burst-mode radio-frequency transmitters. These processing steps, however, entail an undesirable increase in computational effort. This brief presents a multiplierless implementation of a digital aliasing-free pulsewidth modulator using lookup tables, adders, and arithmetic shifts only. Mathematical equations of asymmetric double-edge PWM are given, as well as a modified aliasing-free version of this PWM technique that directly integrates the distortion-avoiding signal processing steps into the pulsewidth modulator. Based on these equations, a multiplierless implementation of the aliasing-free PWM (AF-PWM) is developed. Simulation results obtained with a Simulink fixed-point model show that the proposed modulator implementation provides a feasible solution for realizing AF-PWM with low computational effort.
Year
DOI
Venue
2013
10.1109/TCSII.2013.2268431
Circuits and Systems II: Express Briefs, IEEE Transactions
Keywords
Field
DocType
adders,distortion,modulators,pulse width modulation,signal processing,table lookup,AF-PWM,PWM,Simulink fixed-point model,adders,aliasing distortion,aliasing-free digital pulsewidth modulator,arithmetic shifts,asymmetric double-edge PWM technique,burst-mode radio-frequency transmitters,digital audio amplification,digital pulsewidth-modulated signals,distortion-avoiding signal processing,lookup tables,mathematical equations,multiplierless implementation,nonconstant amplitude signals,pulsed signals,Aliasing-free digital pulsewidth modulation (PWM),burst-mode radio-frequency (RF) transmitters,computational effort,switched-mode power amplifiers (PAs)
Lookup table,Signal processing,Adder,Control theory,Pulse-width modulation,Modulation,Electronic engineering,Aliasing,Digital audio,Distortion,Mathematics
Journal
Volume
Issue
ISSN
60
9
1549-7747
Citations 
PageRank 
References 
4
0.42
8
Authors
3
Name
Order
Citations
PageRank
Katharina Hausmair140.42
Peter Singerl240.42
Christian Vogel336128.88