HFIA Position Paper on HF Channel Simulator Modem Testing

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HFIA Position Paper on HF Channel Simulator /
Modem Testing

• W.N.Furman / J. W. Nieto
• wfurman_at_harris.com, jnieto_at_harris.com
• Harris Corporation
• RF Communications Division

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Background

• Modems tested with similar channel simulators,
  both implemented under existing guidelines, can
  have different results.
• Previous work has shown that existing guidelines
  do not specify HF channel simulators adequately.
• HFIA June 2000
• Nordic HF01
• HFIA June 2002
• At the last HFIA meeting it was suggested that
  the HFIA put together a working group to generate
  a white/position paper on this topic.

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Goals of This Meeting

• Discuss feasibility of position paper
• Discuss alternatives
• Software library
• Discuss format
• Create list of topics that must be addressed
• HF01 paper as a starting point
• Create e-mail list so that a document can be
  passed around, comments can be collected, and a
  draft paper generated for the next HFIA meeting

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Channel Simulator Elements
Frequency Offset
Fading Process
Power Calibration
Frequency Offset
Fading Process
A/D
Tx Filter
Hilbert
Delay
D/A
AGC
Rx Filter

CCIR 322 Noise
Jammer Suite
Gaussian Noise
Core Functions
Added Features
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HF Channel Simulator Topics

• Basic Parameters
• Sampling rate
• A/D D/A precision
• Clock stability
• Floating point / fixed point
• Electrical Interface
• GUI / debugging
• Baseband / RF
• Others?

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HF Channel Simulator Topics

• Mutipath
• Maximum number of paths
• Power control for each path
• Delay range
• Doppler spread
• Min/max supported
• Independence
• SNR
• Min/max

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HF Channel Simulator Topics

• Calibration
• Transmit/Receive radio filtering
• Considered?
• Type?
• Hilbert Transform
• Design parameters
• Frequency offset and differential frequency
  offset

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HF Channel Simulator Topics

• Fading tap generation process
• Spectral shape
• Interpolation
• Noise Generation
• AWGN
• CCIR 322

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HF Channel Simulator Topics

• Jammers
• Types
• Parameters
• Dynamic range issues with large jammers
• AGC
• Considered?
• Type

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The Way Ahead
?