ANALYSIS OF MEDIUM- AND HIGH-FREQUENCY ATMOSPHERIC RADIO NOISE IN THAILAND
Special technical rept. no. 37
STANFORD RESEARCH INST MENLO PARK CA
Pagination or Media Count:
Measurements of atmospheric radio noise have been made in Thailand since early 1966 using equipment similar to the ARN-2 noise-measuring sets employed in the worldwide noise-measuring network coordinated by the Environmental Science Services Administration ESSA of the U.S. Department of Commerce. Emphasis is placed in this report on noise power measurements at 0. 53, 2.3, 5.0, and 10.0 MHz. The analysis of data from almost two years of measurements shows that the variation in the magnitude of noise power from day to night in Thailand is typically 25 dB and indicates that a seasonal variation of about 10 dB is superimposed upon the diurnal effect. The day-to-day variation of noise power at any given hour is considerable. An investigation of the effects of local electrical storms--as indicated by lightning-flash counters--shows that the hour by average noise power tends to increase as the number of flash counts increases, and this effect is greater at the lower frequencies.
- Atmospheric Physics
- Radio Communications