Effects of Cyclic Prefix Jamming Versus Noise Jamming in OFDM Signals

Abstract

Signal jamming of an orthogonal frequency-division multiplexing (OFDM) signal is simulated in MATLAB. Two different means of jamming are used to see, which is a more efficient way to disrupt a signal using the same signal power. The first way is a basic additive white Gaussian noise (AWGN) jammer that equally jams the entire signal. The second way is an AWGN jammer that targets only the cyclic prefix (CP) of the signal. These two methods of jamming are simulated using different channel models and unknowns to get varying results. The three channel models used in the simulations are the no channel case, the simple multipath case, and the fading multipath case. The general trend shows that as the channel model becomes more complex, the difference in the effectiveness of each jamming technique becomes less. The unknown in this research is the symbol-time delay. Since OFDM signals are characterized by multipath reception, the signal arrives at a symbol-time delay which is known or unknown to the jamming signal and the receiver. Realistically, the symbol-time delay is unknown to each and in that case, a Maximum Likelihood (ML) Estimator is used to find the estimated symbol-time delay. This research simulates the symbol-time delay as a known and an unknown at the jammer and receiver. The general trend shows that jamming the cyclic prefix is more effective than noise jamming when the symbol-time delay is unknown to the receiver.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 2011
Accession Number
ADA541883

Entities

People

  • Amber L. Scott

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Cyber
  • Energy and Power Technologies
  • Space

DTIC Thesaurus Topics

  • 4G Wireless Networks
  • Air Force
  • Air Force Research Laboratories
  • Data Transmission
  • Frequency Bands
  • Frequency Division Multiple Access
  • Global Positioning Systems
  • Governments
  • Information Operations
  • Intersymbol Interference
  • Mobile Phones
  • Modulation
  • Multiple Access
  • Orthogonal Frequency Division Multiplexing
  • Radar
  • United States Government
  • Wireless Communications

Fields of Study

  • Engineering

Readers

  • Radio communications and signal processing.