50th Gps Satellite Ready To Launch

[+PDOP's]

U.S. ready to launch its 50th GPS satellite

[+Hemlock]

The amount of technical details in this article is interesting to me. Surprisingly, I understand most of it except one thing.

The solid-propellant third stage is then lit, boosting its cargo into a highly elliptical orbit stretching from 101 nautical miles at perigee to 10,998 nautical miles at apogee. The inclination is expanded to 39.0 degrees on either side of the equator.

....

In the following days, the satellite will circularize its orbit at 11,000 miles and raise the orbital inclination to 55 degrees to join the GPS constellation.

How exactly does it "circularize its orbit"?

[+Wienerdog]

To circularize the orbit the satellite maneuvering rocket is fired briefly at the high point of the orbit over a period of several passes. The added velocity “lifts” the orbital low point each time around until the low and high points are equal or circular at a height of around 11,000-12,000 miles.