Instead of handing satellite operators raw time-tagged position tables (forcing every operator to extrapolate on his own), orbit data can be delivered as Chebyshev polynomial coefficients that directly encode the state vector and covariance matrix over a time span — derived from a reference orbit by a least-squares fit with a modified geopotential, producing orbit information of predetermined, bounded accuracy for any Earth orbit.

— In our words · Source: Providing orbit information with predetermined bounded accuracy (Vitali Braun)