Accession Number : AD0617361

Title :   COMPARISON OF HF PROPAGATION PREDICTIONS AND OBLIQUE-INCIDENCE SOUNDER OBSERVATIONS ON THE OKINAWA/OAHU CIRCUIT.

Descriptive Note : Interim rept. no. 2,

Corporate Author : STANFORD RESEARCH INST MENLO PARK CALIF

Personal Author(s) : Bartholomew,Richard R.

Report Date : DEC 1964

Pagination or Media Count : 34

Abstract : The propagating frequencies predicted by the United States Army Signal Radio Propagation Agency (RPA) for the Okinawa/Oahu trunk are compared with frequencies observed by an oblique-incidence sounder circuit paralleling the communication trunk. Predictions derived from the world-wide frequency predictions made by the National Bureau of Standards Central Radio Propagation Laboratory (CRPL) are also compared with the sounderobserved frequencies. The predicted maximum usable frequency (MUF) is compared with the monthly median of the observations for three months, and the predicted lowest usable frequency (LUF) is compared with the monthly median of the observations for two months. The observations on the Controllers Data Display (CDD) are compared with observations on film records and found to be in good agreement. It is shown that neither the RPA or the CRPL MUF predictions truly represent median conditions on this trunk. The MUF is higher than almost 80 percent of the observations; the FOT (0.85 MUF) exceeds the median of the observations for 56 percent of the time. The LUF predictions are found to be representative of median conditions but with a slight tendency to be higher than the observations. (Author)

Descriptors :   (*HIGH FREQUENCY, RADIO TRANSMISSION), (*IONOSPHERIC PROPAGATION, HIGH FREQUENCY), HAWAII, RYUKYU ISLANDS, ATMOSPHERIC SOUNDING, RADIOSONDES

Distribution Statement : APPROVED FOR PUBLIC RELEASE