Focused assistance data for WiFi access points and femtocells

摘要

Systems, apparatus and methods for reducing a long list of access points (APs) to a short list of access points are presented. Advantageously, a mobile device only need to search for access points on the short list thereby more quickly discovering access points, saving battery power, determining a position fix based on the discovered access points, and reducing a time to fix. Embodiments enable a mobile device to determine which access points should be detectable at a new location of the mobile device. Various embodiments comprise: (1) a linked database; (2) a grouped database; (3) an associated database; and (4) database feedback.

主权项

1. A method in a mobile device for determining a position fix in a wireless network, the method comprising:
determining a first position fix of the mobile device; receiving, at the mobile device, a linked database from a location server, wherein the linked database is in response to the first position fix of the mobile device, comprising a first set of access points associated with the first position fix of the mobile device, and wherein
the linked database provides links associating access points in the first set of access points with corresponding sets of access points, wherein an at least one link to a corresponding set of access points indicates access points that are visible, for determining a second position fix, utilizing at least one radio frequency (RF) scan conducted in a coverage area of an associated access point in the first set of access points; searching for access points in the first set of access points utilizing at least one radio frequency (RF) scan conducted in the coverage area of a first access point in the first set of access points; and discovering for position determination a second set of access points based on the first access point that is visible and the at least one link between the first access point and the corresponding set of access points associated with the first access point provided in the linked database, and wherein the second position fix for the mobile device is determined using the second set of access points.