Antenna Orientation
Q: What is the “Antenna Orientation” in the Fixed Facility database? Is it the Azimuth for the antenna’s major lobe?
A: Orientation and Azimuth (for the major lobe of the antenna directional pattern) usually are the same. The idea is, "How much do I need to rotate the pattern from the way it looks in the library from the manufacturer to make it point the way I want?"
If all manufacturers recorded their patterns with the major lobe to the North (like a compass when you read a map) then Orientation and Azimuth would be the same thing and we would call it Azimuth and there would be less confusion.
However, since some manufacturers choose to show their patterns with the major lobe to the right we use the idea of Orientation to indicate the amount the antenna pattern needs to be rotated.
For example, suppose you have a pattern with the major lobe to the north at 0 degrees and you want your coverage to the southeast (on Azimuth 135).
In this case you would enter an orientation of 135, the program would rotate the antenna 135 degrees and the major lobe would be pointing where you want it.
BUT, if the antenna you want to use has the major lobe pointing to the right, then the pattern needs to be rotated 45 more degrees to point on an Azimuth of 135 - in that case the Orientation would not be the same as the Azimuth. This is relatively rare, but you need to notice how the pattern is in the library and then assign the Orientation value to get the antenna major lobe pointed in the desired direction.
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