Paper Info
Title
Aliasing-Free Digital Pulse-Width Modulation for Burst-Mode RF Transmitters.
Abstract
Burst-mode operation of power amplifiers (PAs) is a promising concept towards higher power efficiency in radio frequency (RF) transmitters. Such transmitters use pulse-width modulation (PWM) to create the driving signal for the PA, and a reconstruction filter after amplification to obtain the transmission signal. However, conventional digital pulse-width modulated signals contain a large amount of distortion that cannot be removed by the reconstruction filter in a satisfactory manner.This paper introduces a method for digital PWM that is free of destructive aliasing distortion. First, a set of mathematical closed-form equations fully describing all baseband processing steps required in conventional PWM-based RF transmitters is developed. Analysis of the equations leads to the conclusion that destructive distortion in digital PWM systems originates from aliasing induced by the infinite bandwidth of pulsed signals that is entailed by the nonlinear operation of the pulse-width modulator. Based on this knowledge, a PWM method is developed that ensures that the generated signals are bandlimited and hence completely avoids destructive aliasing distortion. Simulations as well as measurements demonstrate the improvement that can be achieved with the proposed method compared to conventional methods. The results indicate that by using the proposed method it becomes feasible to implement filters that allow for obtaining satisfying transmission signal quality.
Year
DOI
Venue
2013
10.1109/TCSI.2012.2215776
IEEE Trans. on Circuits and Systems
Keywords
Field
DocType
distortion,power amplifiers,pulse width modulation,radio transmitters,PWM-based RF transmitters,aliasing distortion,aliasing-free digital pulse-width modulation,amplification,baseband processing,burst-mode RF transmitters,burst-mode operation,destructive aliasing distortion,digital PWM systems,digital pulse-width modulated signals,power amplifiers,pulse-width modulation,pulse-width modulator,radio frequency transmitters,transmission signal,transmission signal quality,Aliasing distortion,Fourier series expansion,burst-mode operation,pulse-width modulation (PWM),radio frequency (RF) transmitters
Transmitter,Reconstruction filter,Pulse-width modulation,Pulse-frequency modulation,Electronic engineering,Modulation,Aliasing,Amplitude modulation,Mathematics,Amplifier
Journal
Volume
Issue
ISSN
60-I
2
1549-8328
Citations 
PageRank 
References 
14
1.02
9
Authors
4
Name
Order
Citations
PageRank
Katharina Hausmair1201.86
Shuli Chi2222.50
Peter Singerl3466.20
Christian Vogel436128.88