Qualcomm Incorporated

Vijay Kumar Dewangan

Praveen Dua

Purushotham Kamath

Sivakumar Panneer Selvam

A network based positioning (NBP) system is disclosed that allows any of its access points (APs) to initiate ranging operations with a station device (STA), regardless of whether the STA is in power save mode and regardless of whether a particular AP is currently associated with the STA. For example, to initiate ranging operations with the STA from a non-associated AP, the non-associated AP obtains the TSF timer of the associated AP, and then uses the obtained TSF timer to derive the associated AP's beacon transmission schedule and thereby determine when the STA's corresponding wake-up periods occur. Thereafter, the non-associated AP can initiate ranging operations with the STA during the STA wake-up periods, thereby ensuring that probes sent from the non-associated AP will arrive at the STA while the STA is awake from power save mode.

Method for ranging to a station in power saving mode

A wireless network is disclosed that allows an access point (AP) to keep a station (STA) in an awake state for an extended duration by periodically sending 'keep-awake' frames to the STA. The keep-awake frames may be NULL frames having an asserted 'more data' bit. For some embodiments, the AP transmits a beacon frame to the STA, wherein the beacon frame includes an asserted traffic indication bit that causes the STA to remain in the awake state for an additional wake-up period. Then, the AP transmits a sequence of keep-awake frames to the STA, wherein each keep-awake frame causes the STA to remain in the awake state for an additional time period.

Method and apparatus for extending an awake state of a station

A wireless local area network (WLAN) positioning system is disclosed that allows the WLAN system to determine the location attributes of a client device operating in a power save mode, operating on a different channel than the WLAN's access points, and/or operating in an ad-hoc mode. The client device periodically performs scanning operations during which beacon frames broadcast by a selected AP(s) can be received. The client device parses information embedded in the beacon frames, and in response thereto selectively initiates ranging operations to determine its location attributes. After determining its location attributes, the client devices sends the location attributes back to the selected AP(s).

Growing community of inventors

Santa Clara, CA, United States of America

Vijay Kumar Dewangan