Abstract: A method for validating time assistance data includes receiving, at a mobile device, the time assistance data via a first wireless communication technology from a serving cell. The method also includes obtaining a reference global navigation satellite system (GNSS) time, at the mobile device, via a second wireless communication technology and determining whether the time assistance data is valid based on the reference GNSS time. Further included in the method is determining a validated GNSS time based on the time assistance data in response to determining that the time assistance data is valid.

Abstract: A method for validating time assistance data includes receiving, at a mobile device, the time assistance data via a first wireless communication technology from a serving cell. The method also includes obtaining a reference global navigation satellite system (GNSS) time, at the mobile device, via a second wireless communication technology and determining whether the time assistance data is valid based on the reference GNSS time. Further included in the method is determining a validated GNSS time based on the time assistance data in response to determining that the time assistance data is valid.

Abstract: Methods and systems are disclosed for processing satellite positioning system (SPS) signals at a mobile device. In an embodiment, SPS signals may be acquired at multiple instances over a first duration while the mobile device is camped on one or more signals transmitted by a first access device. The mobile device may then determine a second duration of time to acquire a subsequent SPS signal based, at least in part, on the acquired SPS signals, representations of system time in signals received from the first access device contemporaneously with acquisition of the SPS signals and an indication of stationarity of the mobile device during the first duration.

Abstract: Disclosed embodiments pertain to combining Reference Signal Time Difference (RSTD) measurements from partial measurement sessions that result when a single measurement session is interrupted by one or more interruption events including Out of Service (OOS) or Inter-Frequency Handover (IFH) events. In some embodiments, first Time Of Arrival (TOA) measurements of cellular signals during a plurality of discontiguous partial measurement sessions separated by one or more interruption events may be obtained. Second TOA measurements based on a reference time source may be obtained for a plurality of the first TOA measurements from at least two partial measurement sessions. A cell associated with a second TOA measurement may be selected as a reference cell and for each non-reference cell associated with a second TOA measurement, a corresponding RSTD measurement may be obtained relative to the selected reference cell.

Abstract: Techniques disclosed herein help a location server identify inaccuracies in a list of neighboring cells provided by the location server by enabling mobile devices to, during an OTDOA session to opportunistically take Reference Signal Time Difference (RSTD) measurements of additional cells not on the neighboring cell list. The mobile device can then provide these RSTD measurements back to the server, which can optimize its algorithm for determining neighboring cells based on these measurements.

Abstract: A mobile device is capable of accurately maintaining a global time based on Satellite Position System (SPS) time decoded from an SPS signal using a clock signal acquired from a wireless communication transmitter, such as a base station or access point. The time uncertainty is reduced or minimized by determining a relative change in position of the mobile device with respect to a base position, e.g., a reference position determined from a previous SPS session. The time uncertainty may be determined based on the relative change in position with respect to the base position by transforming it into time units based on the speed of light. The global time may be updated based on the determined time uncertainty, which may be used in a subsequent SPS session to reduce the search window to acquire SPS satellite signals.

Abstract: Techniques disclosed herein help a location server identify inaccuracies in a list of neighboring cells provided by the location server by enabling mobile devices to, during an OTDOA session to opportunistically take Reference Signal Time Difference (RSTD) measurements of additional cells not on the neighboring cell list. The mobile device can then provide these RSTD measurements back to the server, which can optimize its algorithm for determining neighboring cells based on these measurements.

Abstract: Disclosed embodiments pertain to combining Reference Signal Time Difference (RSTD) measurements from partial measurement sessions that result when a single measurement session is interrupted by one or more interruption events including Out of Service (OOS) or Inter-Frequency Handover (IFH) events. In some embodiments, first Time Of Arrival (TOA) measurements of cellular signals during a plurality of discontiguous partial measurement sessions separated by one or more interruption events may be obtained. Second TOA measurements based on a reference time source may be obtained for a plurality of the first TOA measurements from at least two partial measurement sessions. A cell associated with a second TOA measurement may be selected as a reference cell and for each non-reference cell associated with a second TOA measurement, a corresponding RSTD measurement may be obtained relative to the selected reference cell.