Page 104 - Satellite Communications, Fourth Edition
P. 104
84 Chapter Three
Figure 3.4 Azimuth-elevation angles for an earth-station location of
48.42°N, 89.26°W (Thunder Bay, Ontario). Ku-band satellites are shown.
The preceding results do not take into account the case when the
earth station is on the equator. Obviously, when the earth station is
directly under the satellite, the elevation is 90°, and the azimuth is
irrelevant. When the subsatellite point is east of the equatorial earth
station (B < 0), the azimuth is 90°, and when west (B > 0), the azimuth
is 270°. Also, the range as determined by Eq. (3.11) is approximate, and
where more accurate values are required, as, for example, where prop-
agation times need to be known accurately, the range is determined by
measurement.
For a typical home installation, practical adjustments will be made to
align the antenna to a known satellite for maximum signal. Thus the look
angles need not be determined with great precision but are calculated
