Accession Number : ADA189132

Title :   HF (High Frequency) Maximum Usable Frequency (MUF) Model Uncertainty Assessment.

Descriptive Note : Research rept.,

Corporate Author : NAVAL OCEAN SYSTEMS CENTER SAN DIEGO CA

Personal Author(s) : Roy, T N ; Sailors, D B

PDF Url : ADA189132

Report Date : Jun 1987

Pagination or Media Count : 116

Abstract : A statistical analysis of observed oblique sounder median maximum observed frequencies (MOF) and predicted maximum usable frequencies (MUF) was used to assess the accuracy of high-frequency MUF prediction. A database of 13,054 hours of oblique sounder MOFs measured on 70 paths was compared with the predicted MUF values from MINIMUF-3.5, MINIMUF 85, and an unrelated MUF model, the HF Broadcast WARC model (HFBC84). The data were screened into subsets to determine the effect of particular paths, path length and orientation, season, month, latitude, sunspot number, diurnal trends, geographic region, and sounder type. The accuracy of all three models was very close, with the MINIMUF-3.5 model having the lowest RMS error of 4.44 MHz. MINIMUF 85 was next, with an RMS error of 4.58 MHz, and HFBC84 was last, with an error of 4.67 MHz, and MINIMUF 85 last, with 1.28 MHZ. Correlation was good for all three models. Correlation coefficients were .824, .819, and .827 for MINIMUF-3.5, MINIMUF 85, and HFBC84, respectively. Future improvements to the MINIMUF model are discussed and current MUF computer algorithms are included in the appendices. Keywords include: HF propagation, MOF, Maximum observable frequency, MUF, Maximum usable frequency, and HF model, MINIMUF.

Descriptors :   *COMPUTER PROGRAMS, *DIURNAL VARIATIONS, *PROPAGATION, *SOUNDING, ACCURACY, COEFFICIENTS, CORRELATION, FREQUENCY, GEOGRAPHIC AREAS, HIGH FREQUENCY, LATITUDE, LENGTH, PATHS, PATTERNS, SEASONS, STATISTICAL ANALYSIS, SUNSPOTS

Subject Categories : Radiofrequency Wave Propagation
      Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE