Go to  Advanced Search

A new radio frequency switch-mode power amplifier concept for wireless applications

Show full item record

Files in this item

Files Size Format Description   View
ubc_2012_fall_ali_sheikh.pdf 28.20Mb Adobe Portable Document Format   View/Open
 
Title: A new radio frequency switch-mode power amplifier concept for wireless applications
Author: Ali, Sheikh Nijam
Degree Master of Applied Science - MASc
Program Electrical and Computer Engineering
Copyright Date: 2012
Publicly Available in cIRcle 2012-08-27
Abstract: Although RF switch-mode power amplifiers (SMPAs) are theoretically attractive with the potential to achieve very high power efficiencies, experimental realizations at high frequencies have yet to yield significantly better efficiency than conventional analog technology. Most SMPA designs are based on class D or class S circuits, and in these circuits, power efficiency is significantly reduced when the switching signal is changed from periodic to non-periodic. In this work, a new SMPA architecture is proposed. Instead of employing reflective out-of-band matching conditions used in class D/S circuits, the switch is matched to a broadband load which creates dissipative out-of-band impedances. The broadband load significantly improves switching conditions especially for non-periodic signals. The broadband load is implemented as a complementary diplexer which separates in-band and out-of-band signal power at the output of the SMPA. An energy recovery loop using out-of-band signal power is proposed to significantly reduce the sensitivity of the overall power efficiency to changes in the peak to average power ratio of the source signal. Experimental and simulation results are shown for the new SMPA architecture.
URI: http://hdl.handle.net/2429/43065
Scholarly Level: Graduate

This item appears in the following Collection(s)

Show full item record

All items in cIRcle are protected by copyright, with all rights reserved.

UBC Library
1961 East Mall
Vancouver, B.C.
Canada V6T 1Z1
Tel: 604-822-6375
Fax: 604-822-3893