Why are there so many satellite locations?

DIRECTV uses four satellite locations for US HD programming. DISH uses two different sets of three. If you have international programming, tack on another two satellite locations. Why is that all so necessary?

Here’s the thinking. A satellite is just about the size of a car give or take. An orbital “slot” like the 101 degree spot where DIRECTV has its satellites is about 420 miles wide. You’d think that they could put a lot of satellites in that 420 miles, right?

Well right but…

There are rules for how widely spaced satellites must be. This is partially because satellites tend to drift around a little bit and if they hit each other that would be BAD. It’s also because satellites run on solar power so we don’t want them casting shadows on each other, and partially because we don’t want the high-powered beams from each satellite to interfere with each other. A little bit of research suggests that each satellite must be about 46 miles from each other one, meaning that precious 101 slot, which is right in the middle of the country and does such a good job covering it, can only hold 9 satellites. There are other companies who want that “slot” so there’s some competition there. There is also a limitation as to how much satellite bandwidth can be allocated to each location, and that is a concern as well.

When they chose to expand, DIRECTV got some prime real estate right in the middle of the country, at the 99 and 103 slots, while phasing out their other slots at 110 and 119. On the other hand, DISH chose to have two sets of three satellites, one on the far west end of the US and one on the east. This choice actually saved them money since even though satellites themselves cost a lot of money. The cost of those highly desirable mid-South licenses was the real dealbreaker.

In the next 18 months or so DIRECTV will be moving all residential broadcasts to the 99/101/103 range which will make aiming easier. It could possibly lead to smaller dishes but that’s not likely as DIRECTV seems to have settled into its slimline dish design.