A satellite navigation system using multiple antennas for providing the
position of multiple fiduciary points on an object even when fewer than
four satellites are visible to some or all the antennas. Satellite
signals from the multiple antennas are fed into at least one receiver.
The receiver or receivers utilize constraint information, which is
independent of the satellite signals. These external constraints are used
to augment the signals received from the satellites, to obtain the
position solution for each antenna. In a preferred embodiment, a common
reference clock is used to provide an external constraint. Examples of
other external constraints that can be used in the current invention are
distance between the antennas, inertial measurement of attitude,
rotational or linear position sensors, etc.