Yes thats correct as long as the satelittes are designed to work with the base station. 

If they're DECT phones you can have up to six handsets.

danepak: Thanks.
Just looking at something basic where they come in a pack of 2 (where one of them rests on a base station).

Yup then that would work where the 2nd phone only needs power. Once its charged - its doesnt even need that because it communicates to the base station all of the time via DECT. It just needs power to charge it.