Satellite positioning system signal searching methods and apparatuses

An apparatus comprising:

• a satellite positioning system (SPS) receiver;
• memory having stored therein an initial search order for a plurality of SPS signals transmitted from a corresponding plurality of space vehicles (SVs), said initial search order being based, at least in part, on an estimated relative position for each SV;
• and
• at least one processing unit coupled to said SPS receiver and said memory, said at least one processing unit to signal said SPS receiver to:
• selectively initiate a search for at least a first one of said plurality of SPS signals in a received RF signal according to said initial search order, and in response to at least identifying at least said first one of said plurality of SPS signals in said received RF signal, said first one of said plurality of SPS signals being transmitted by a first SV,
• access a refined search order comprising at least a portion of said plurality of SPS signals that have not been searched for, said refined search order being based, at least in part, on an estimated relative position of said first SV, and
• selectively initiate a search for at least a second one of said plurality of SPS signals in said received RF signal according to said refined search order.

An apparatus comprising:

• means for receiving satellite positioning system (SPS) signals
• means for specifying an initial search order for a plurality of said SPS signals transmitted from a corresponding plurality of space vehicles (SVs), said initial search order being based, at least in part, on an estimated relative position for each SV;
• means for selectively searching for and identifying at least a first one of said plurality of SPS signals in a received RF signal according to said initial search order, said first one of said plurality of SPS signals being transmitted by a first SV;
• means for specifying a refined search order comprising at least a portion of said plurality of SPS signals that have not been searched for, said refined search order being based, at least in part, on an estimated relative position of said first SV;
• and
• means for selectively searching for at least a second one of said plurality of SPS signals in said received RF signal according to said refined search order.

An article comprising:

• a computer readable medium having computer implementable instructions stored thereon which if implemented by one or more processing units in a specific apparatus that is for use in and/or with a Satellite Positioning System (SPS) receiver operatively enable the specific apparatus to:
• access an initial search order for a plurality of SPS signals transmitted from a corresponding plurality of space vehicles (SVs), said initial search order being based, at least in part, on an estimated relative position for each SV;
• selectively initiate a search for at least a first one of said plurality of SPS signals in a received RF signal according to said initial search order, and in response to at least identifying at least said first one of said plurality of SPS signals in said received RF signal, said first one of said plurality of SPS signals being transmitted by a first SV;
• access a refined search order comprising at least a portion of said plurality of SPS signals that have not been searched for, said refined search order being based, at least in part, on an estimated relative position of said first SV;
• and
• selectively initiate a search for at least a second one of said plurality of SPS signals in said received RF signal according to said refined search order.