Methods and apparatuses for searching for satellite signals are provided.
One of the proposed methods of searching for satellite signals includes:
searching for satellite signals according to measurement predictions;
searching for satellite signals of a reference satellite without
referring to the measurement predictions; determining if measurements
derived from the reference satellite are consistent with the measurement
predictions; and searching for satellite signals of other satellites
without referring to the measurement predictions if the measurements
derived from the reference satellite are determined to be inconsistent
with the measurement predictions. If the measurements derived from the
reference satellite are determined to be inconsistent with the
measurement predictions, navigation information for use in the generation
of the measurement predictions is determined to be stale.