The Effect of Scintillations on Transionospheric Communications
ELECTRONICS RESEARCH LAB ADELAIDE (AUSTRALIA)
Pagination or Media Count:
Consideration is given to the bearing ionospheric scintillation on the design and on the evaluation of the performance of satellite communication links. Emphasis is placed on establishing a design parameter of universal application. The cumulative amplitude distribution function cdf, which was found application in this regard, is shown experimentally to be well represented by the Nakagami m-distribution at all scintillation levels. However, the cdf is demonstrated to be strictly valid only for amplitude modulated signals of short duration. Autocorrelation, power spectra and level crossing techniques are investigated in an effort to establish a design parameter more universally applicable than the cdf. A quantity message reliability, is defined which removes the short duration restriction inherent in the cdf. A formula for message reliability is developed which allows it to be evaluated for any fade margin and message length, given the scintillation index and the half width of the autocorrelogram of the scintillating channel. A design chart, embodying this information, is also illustrated.
- Atmospheric Physics
- Radiofrequency Wave Propagation
- Radio Communications