English: Parabolic antenna used in the White Alice Communication System built around 1958 in Alaska by Western Electric and the US Air Force, which provided telephone communication between isolated communities. It was a tropospheric scatter system; large antennas like this beamed 50 kW signals at about 900 MHz at a low angle into the horizon, where they scattered off the tropopause, with a tiny fraction returning to Earth beyond the horizon. Looking East. The tower at right supports the feed horn for the antenna. The system became obsolete with the advent of communications satellites in the 1960s.