Relative Coverage of Large Ground Antennas

The relative coverages provided by an Azimuth-Elevation (Az-El) mount antenna and an equitorial mount antenna are computed and sketched in a plane tangent to the earth's surface at the antenna site. Coverage diagrams are determined for polar orbiting satellites as a function of altitude and with the allowable antenna movements about the polar and declination axis as parameters. The extent of the field of view blocked by imposing a masking angle is also considered and qualitative estimates of the relative dynamic coverages are presented. Advantages offered by each particular type of antenna are dependent upon the orbit and mission of the vehicle being tracked.