1. A method for measuring energy potential in a receiver receiving signals from a plurality of navigation satellites, comprising the steps of: digitizing, by a central processing unit, said received signals; removing, by the central processing unit, information symbols from said digitized received signals; calculating, by the central processing unit, a correlation signal I; averaging, by the central processing unit, said correlation signal I over a time interval T M to obtain an estimate I n of an expected value MI; calculating, by the central processing unit, a variance estimate D n of said correlation signal I over a time interval T D , wherein the time interval T D is greater than the time interval T M ; and calculating, by the central processing unit, an estimate SNR e of energy potential according to the algorithm 
 SNR e =20 log 10 ( I n )− K c −η dB-Hz; wherein: K c is a characteristic constant based at least in part on said variance estimate D n , and η is an energy loss based on digital processing.