A first location determining receiver determines a first location estimate
of a vehicle. The first location determining receiver is associated with
satellite beacons. A second location determining receiver determines a
second location estimate of a vehicle. The second location determining
receiver is exclusively associated with terrestrial beacons. A selector
selects the first location estimate of the vehicle as a preferential
location in accordance with an initialization scheme for the vehicle in a
work area. A filtering module applies a first weight to a first location
and a second weight to the second location to derive a weighted estimate
as the preferential location upon satisfactory completion of the
initialization scheme.