Title page for ETD etd-09082000-23270013

Type of Document Master's Thesis
Author Johnson, Daniel Eric
Author's Email Address dej@vt.edu, dej@n4scs.dyn.dhs.org
URN etd-09082000-23270013
Title Adaptive Digital Predistortion with Applications for LMDS Systems
Degree Master of Science
Department Electrical and Computer Engineering
Advisory Committee
Advisor Name Title
Bostian, Charles W. Committee Chair
Reed, Jeffrey Hugh Committee Member
Sweeney, Dennis G. Committee Member
  • Nonlinear Amplification
  • Broadband
  • Measurement
  • AM-PM
  • AM-AM
  • Simulation
Date of Defense 2000-08-25
Availability unrestricted
A limiting factor in the widespread deployment of LMDS systems is the limited distance of current systems. Rain attenuation and limited transmitter power are the primary causes of the limited distance. Adaptive digital predistortion is presented as a method of increasing effective transmitter power.

A background on LMDS link design, non-linear amplification, and predistortion is presented to assist the reader. A developed simulation uses AM-AM and AM-PM characteristics obtained from laboratory measurements of a 28 GHz amplifier to determine the effect of several predistortion implementation options and to confirm the feasibility of the proposed architecture.

The potential impact of this predistortion architecture on LMDS system design is considered. The presented multi-stage predistortion architecture is found to be capable of implementation at Msymbol/second rates utilizing a FPGA or custom IC and a moderate speed digital signal processor.

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  dej-thesis.pdf 990.06 Kb 00:04:35 00:02:21 00:02:03 00:01:01 00:00:05

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