Long-Range Fading Prediction and Realistic Physical Modeling to Enable Adaptive Transmission for Mobile Radio Networks

Abstract

The feasibility of adaptive transmission enabled by Long Range Fading Prediction (LRP) was investigated for rapidly varying fading channels encountered in peer-to-peer mobile communication systems. The LRP algorithms were tested using the standard Jakes model and the realistic physical model developed by the Principal Investigators. This research was an interdisciplinary effort in communication theory, physics, and signal processing. Correlated fading was exploited in the development of the LRP algorithm to enable adaptive modulation for a Frequency Hopping Spread Spectrum (FH/SS) mobile radio channel. Adaptive frequency diversity transmission for FH systems with partial band interference also was explored. Significant performance gains were demonstrated relative to non-adaptive methods. Efficient channel loading for wireless Adaptive Orthogonal Frequency Division Multiplexing (AOFDM) systems aided by robust LRP was investigated and reduced feedback techniques were developed. The bit rates approaching those of AOFDM with perfect knowledge of fading conditions were achieved. Several linear and nonlinear Multi-Access Interference (MAI) mitigation and frequency diversity combining transmitter precoding methods aided by the LRP were developed for the downlink of the Direct Sequence Spread Spectrum (DS/SS) systems. The proposed techniques were shown to improve upon previously proposed precoding and detection methods while providing the desired performance/complexity trade-off.

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Document Details

Document Type
Technical Report
Publication Date
May 18, 2005
Accession Number
ADA433759

Entities

People

  • A. Duel-hallen
  • H. Hallen

Organizations

  • North Carolina State University

Tags

Communities of Interest

  • Human Systems

DTIC Thesaurus Topics

  • Algorithms
  • Channel State Information
  • Code Division Multiple Access
  • Communication Systems
  • Detection
  • Frequency
  • Frequency Agility
  • Frequency Diversity
  • Frequency Division Multiplexing
  • Information Science
  • Modulation
  • Multiple Access
  • Multiplexing
  • Orthogonal Frequency Division Multiplexing
  • Radio Equipment
  • Spread Spectrum
  • Wireless Communications

Fields of Study

  • Engineering

Readers

  • Radio communications and signal processing.