Wireless position determination using adjusted round trip time measurements

An apparatus for wireless position determination, comprising:

• a wireless transceiver;
• a processor coupled to the wireless transceiver;
• and
• a memory coupled to the processor, wherein the memory stores executable instructions and data for causing the processor to
• measure a round trip time (RTT) to each of a plurality of wireless access points,
• estimate a first distance to each wireless access point based upon the round trip time delay and an initial processing time associated with each wireless access point,
• estimate a second distance to each wireless access point based upon supplemental information,
• combine the first and second distance estimates to each wireless access point, and
• calculate the position of the mobile station based upon the combined distance estimates.

An apparatus for wireless position determination, comprising:

• means for measuring a round trip time (RTT) to each of a plurality of wireless access points;
• means for estimating a first distance to each wireless access point based upon the round trip time delay and an initial processing time associated with each wireless access point;
• means for estimating a second distance to each wireless access point based upon supplemental information;
• means for combining the first and second distance estimates to each wireless access point;
• and
• means for calculating the position of the mobile station based upon the combined distance estimates.

A method for wirelessly determining a position of a mobile station using signals provided by a plurality of wireless access points, comprising:

• measuring a distance to each wireless access point based upon a wireless signal model;
• calculating a position of the mobile station based upon the measured distance;
• determining a computed distance to each wireless access point based upon the calculated position of the mobile station;
• updating the wireless signal model based upon the measured and computed distances to each wireless access point;
• and
• determining whether the wireless signal model has converged.

An apparatus for wireless position determination of a mobile station using signals provided by a plurality of wireless access points, comprising:

• a wireless transceiver;
• a processor coupled to the wireless transceiver;
• and
• a memory coupled to the processor, wherein the memory stores executable instructions and data for causing the processor to
• measure a distance to each wireless access point based upon a wireless signal model,
• calculate a position of the mobile station based upon the measured distance,
• determine a computed distance to each wireless access point based upon the calculated position of the mobile station,
• update the wireless signal model based upon the measured and computed distances to each wireless access point, and
• determine whether the wireless signal model has converged.

An apparatus for wireless position determination of a mobile station using signals provided by a plurality of wireless access points, comprising:

• means for measuring a distance to each wireless access point based upon a wireless signal model;
• means for calculating a position of the mobile station based upon the measured distance;
• means for determining a computed distance to each wireless access point based upon the calculated position of the mobile station;
• means for updating the wireless signal model based upon the measured and computed distances to each wireless access point;
• and
• means for determining whether the wireless signal model has converged.

A method for wirelessly determining a position of a mobile station, comprising:

• measuring a round trip time delay to each of a plurality of wireless access points;
• estimating an initial processing time for each of the wireless access points;
• calculating the position of the mobile station based upon the measured round trip time delays and estimated processing times;
• and
• updating the estimated processing time for each of the wireless access points based upon the calculated position of the mobile station.

An apparatus for wirelessly determining a position of a mobile station, comprising:

• a wireless transceiver;
• a processor coupled to the wireless transceiver;
• and
• a memory coupled to the processor, wherein the memory stores executable instructions and data for causing the processor to
• measure a round trip time delay to each of a plurality of wireless access points,
• estimate an initial processing time for each of the wireless access points,
• calculate the position of the mobile station based upon the measured round trip time delays and estimated processing times, and
• update the estimated processing time for each of the wireless access points based upon the calculated position of the mobile station.

An apparatus for wirelessly determining a position of a mobile station, comprising:

• means for measuring a round trip time delay to each of a plurality of wireless access points;
• means for estimating an initial processing time for each of the wireless access points;
• means for calculating the position of the mobile station based upon the measured round trip time delays and estimated processing times;
• and
• means for updating the estimated processing time for each of the wireless access points based upon the calculated position of the mobile station.