|
NISCAIR ONLINE PERIODICALS REPOSITORY (NOPR) >
NISCAIR PUBLICATIONS >
Research Journals >
Indian Journal of Radio & Space Physics (IJRSP) >
IJRSP Vol.41 [2012] >
IJRSP Vol.41(3) [June 2012] >
| Title: | Duct-induced terrestrial microwave link degradation in Nigeria: Minimization factors |
| Authors: | Oyedum, O D |
| Keywords: | Surface duct
Shadow zone
Antenna height
Signal degradation
Link degradation
Link disruption
Terrestrial microwave path fading loss |
| Issue Date: | Jun-2012 |
| Publisher: | NISCAIR-CSIR, India |
| PACS No.: | 41.20jb; 92.60.Ta |
| Abstract: | Radio propagation at VHF and higher frequency bands are characterized by
fading and anomalous enhancements associated with meteorological conditions. In
particular, link disruptions on line-of-sight terrestrial microwave paths are
often associated with fading losses that often depend on the height and
position of the receiver as well as season of the year. Such propagation
problems may be minimized by appropriate choice of the height and relative
position of the transmitting and receiving antenna. Using results based on
analysis of radiosonde data obtained during 1991-1999 for surface air
temperature, pressure and relative humidity from the Nigerian meteorological
stations of Lagos (06°28´N,
03°28´E), on the Atlantic coast of
West Africa; and an inland city of Kano (12°02´N, 08°30´E),
height-distance curves have been derived for estimating suitable heights and
relative positions of antennas, to minimize fade losses on line-of-sight
terrestrial paths during surface duct events. A detailed account of theoretical
applications of such curves in both cities is also attempted. |
| Page(s): | 339-347 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-105X (Online); 0367-8393 (Print) |
| Source: | IJRSP Vol.41(3) [June 2012]
|
|
