If we consider a constellation of satellites in lower orbits the most efficient plan is to have satellites equally phased within a given orbital plane, and a rough estimate is that if you put them around the equator, the total number of satellites is given to you by an equation N equals to ps, where "p" is the number of planes, and "s" is the number of satellites for plane, and the values of "p" and "s" can be obtained in terms of the central angle, and the central angle is given to us in terms of a relationship which concerns, which is related to the radios of the earth, the satellite orbital altitude, and the minimum elimination angle.

---