https://www.sciencedaily.com/releases/2018/06/180606122638.htm

"It's actually very easy to determine how many satellites you need to get global coverage. You can do the math by hand," said Koki Ho, assistant professor in the Department of Aerospace Engineering at U of I. "But total global coverage isn't necessarily what a company wants or needs.

It might not be the best way for the company to maximize their profit. We looked at different ways to design a satellite constellation that first provides regional coverage and then can be expanded stage by stage, keeping areas with uncertain demand in consideration to maximize profit."