Method and apparatus for measurement processing of satellite positioning system (SPS) signals

A method of measuring times of arrival of satellite signals received in a Satellite Positioning System (SPS) receiver, said method comprising:

• receiving a plurality of SPS signals from a plurality of SPS satellites;
• characterizing a signal environment corresponding to the location in which said SPS receiver is located, to produce environment data;
• selecting threshold values for one or more parameters related to one or more characteristics of said satellite signals using said environment data;
• measuring times of arrival of respective satellite signals from two or more satellites of said plurality of satellites, to produce a plurality of measured times of arrival;
• and
• testing data representing said times of arrival using said threshold values for said one or more parameters to produce a set of times of arrival with which to calculate a location fix for said SPS receiver.

A method of processing satellite positioning system signals received by a satellite positioning system (SPS) receiver, said method comprising:

• receiving a plurality of SPS signals from a plurality of in-view SPS satellites;
• determining an integration period for each of said plurality of SPS signals, said integration period corresponding to a period of time used to perform a time-of-arrival measurement for each corresponding SPS signal;
• determining a maximum correlation peak value and a correlation peak-width for each signal of said plurality of SPS signals;
• determining a code phase corresponding to each said maximum correlation peak value;
• determining a Doppler value for each of said plurality of SPS signals;
• and
• determining one or more signal characteristics associated with each of said plurality of SPS signals.

ASPS receiver apparatus comprising:

• an antenna for receiving SPS signals at an RF frequency from a plurality of inview satellites;
• a downconverter coupled to said antenna, said downconverter reducing the RF frequency of said received SPS signals to an intermediate frequency (IF) to produce a baseband signal;
• a digitizer coupled to said downconverter;
• a processor coupled to said digitizer, wherein said processor is configured to:
• determine a signal environment corresponding to the location in which said SPS receiver is located, to produce environment data;
• select threshold values for one or more parameters related to one or more characteristics of said satellite signals using said environment data;
• measure times of arrival of respective satellite signals from two or more satellites of said plurality of in-view satellites, to produce a plurality of measured times of arrival;
• and
• test data representing said times of arrival using said threshold values for said one or more parameters to produce a set of times of arrival with which to calculate a location fix for said SPS receiver.

A method of processing satellite positioning system (SPS) signals, said method comprising:

• determining a first possible correlation peak for a first set of SPS signals from a first SPS satellite;
• determining a second possible correlation peak for said first set of SPS signals wherein said second possible correlation peak follows said first possible correlation peak in time;
• deriving a measurement representing a time-of-arrival of said first set of SPS signals from one of said first possible correlation peak and said second possible correlation peak;
• transmitting from an SPS receiver which received said first set of SPS signals an identification that said first possible correlation peak and said second possible correlation peak have been determined.

A method of processing satellite positioning system (SPS) signals, said method comprising:

• determining a first possible correlation peak for a first set of SPS signals from a first SPS satellite;
• determining a second possible correlation peak for said first set of SPS signals wherein said second possible correlation peak follows said first possible correlation peak in time;
• deriving a measurement representing a time-of-arrival of said first set of SPS signals from one of said first possible correlation peak and said second possible correlation peak;
• identifying a wide peak correlation output and discarding said wide peak correlation output from measurements used to determine a position information for an SPS receiver which received said first set of SPS signals.

A method of processing satellite positioning system (SPS) signals, said method comprising:

• determining a signal environment data which represents a manner in which SPS signals are propagated in a location at which an SPS receiver is located, wherein said signal environment data comprises data representing at least one of multipath conditions or interference conditions for SPS signals near said location;
• determining how data representing SPS signals received by said SPS receiver is processed based on said signal environment data;
• transmitting measurements representing time-of-arrivals of SPS signals at said SPS receiver;
• receiving at a remote processing system said measurements representing time-of-arrivals through a cellular radio frequency communication link;
• processing at said remote processing system said measurements representing time-of-arrivals to determine a position solution for said SPS receiver.

A method of processing satellite positioning system (SPS) signals, said method comprising:

• determining a first possible correlation peak for a first set of SPS signals;
• determining a second possible correlation peak for said first set of SPS signals;
• deriving a measurement representing a time-of-arrival of said first set of SPS signals from one of said first possible correlation peak and said second possible correlation peak;
• transmitting from an SPS receiver which received said first set of SPS signals an identification that said first possible correlation peak and said second possible correlation peak have been determined.

A method of processing satellite positioning system (SPS) signals, said method comprising:

• determining from a cell based information source a signal environment which represents a manner in which SPS signals are propagated in a location at which an SPS receiver is located;
• determining how data representing SPS signals received by said SPS receiver is processed based on said signal environment;
• determining measurements representing time-of-arrivals of SPS signals, said measurements based on said signal environment;
• transmitting said measurements representing time-of-arrivals of SPS signals at said SPS receiver;
• receiving at a remote processing system said measurements representing time-of-arrivals through a cellular radio frequency communication link;
• processing at said remote processing system said measurements representing time-of-arrivals to determine a position solution for said SPS receiver.

A method of processing satellite positioning system (SPS) signals, said method comprising:

• determining a signal environment data which represents a manner in which SPS signals are propagated in a location at which an SPS receiver is located, wherein said signal environment data comprises data representing at least one of multipath conditions or interference conditions for SPS signals near said location;
• determining how data representing SPS signals received by said SPS receiver is processed based on said signal environment data;
• determining an SPS time-of-arrival measurement;
• correcting said time-of-arrival measurement with a bias adjustment based on said signal environment.