Positioning API Developer's Guide

Tips for Optimizing Data Accuracy

  • To ensure that the Positioning API returns high-quality results, provide high-quality measurements.

    The result quality depends on the measurement freshness and correctness.

  • Your APIs for listing available WLANs may include some old or cached WLANs that are no longer relevant. If such stale WLANs are included in a positioning request, the resulting location estimate may be inaccurate, incorrect, or simply not available.

    Filter out any old WLANs from the measurements and do not send them in your requests.

  • During cell handovers (from one cell to another) and during cell technology handovers (between 2G/3G/4G), the cell parameters returned by external APIs may be temporarily incoherent. For example, the cell identifier may be measured from the new cell, but the LAC code may still be the one for the old cell. Beware of such corrupt measurements, as they may result in incorrect location estimates. They may also even prevent the service from being able to determine a position.

    You can compare several subsequent measurements to better detect such anomalies or recheck the parameter values a few seconds after a cell change is detected.

  • During an ongoing call or data transfer, the cell identifier reported by your APIs may be stale. The values may identify the cell in which the call started, instead of the current cell, when the device has moved during the call.

    In such cases, the location estimate can be incorrect. You can detect these situations on the client side by checking the Radio Resource Control State.

  • Include cell measurements in a WLAN-based positioning requests to get better positioning results.