Evaluation of Coherent FSK Performance in Atmospheric Radio Noise.
Abstract
Communications in the very low frequency/low frequency range are primarily degraded by the influence of atmospheric radio noise ARN. It is the purpose of this thesis to evaluate the performance of a continuous frequency shift keying (CFSK) communications system operating in an ARN channel. Beckmann's model for the amplitude probability distribution (PDF) of the envelope voltage for ARN is used in the analysis. Beckmann's model provides a theoretical foundation for an empirical APD compiled by Crichlow. The parameters for Beckmann's model are determined which give APD curves that correspond to Crichlow's statistics for Vd ratios of 4 and 5. The marginal density for the in-phase component of ARN is derived from Beckmann's noise model. The performance of a binary CFSK detector operating in an ARN channel is calculated using the very low frequency/low frequency derived in phase density. The M-ary performance is also calculated is also calculated for M equal to 3 and 4. A comparison is made to experimental CFSK performance data. The theoretical performance curves provide a tight upper bound on the probability of error for the experimental performance. The conclusion is reached that the probability of error for ARN does not decrease significantly with an increase in signal-to-noise ratio. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1977
- Accession Number
- ADA055237
Entities
People
- Allen L. Nejezchleb
Organizations
- Air Force Institute of Technology