Patent · US Active

Locationing using differential phase measurements of IEEE 802.11 preambles

US9137680B2 · kind B2 · utility

1Cited by
1References
15Claims
0Family size

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Key dates

Filing dateOct 3, 2012
Grant dateSep 15, 2015
Priority date—
Expiry dateMar 13, 2034

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04W64/00
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and apparatus for locationing using differential phase measurements of IEEE 802.11 preambles. A first step includes providing a local clock at the same frequency as the IEEE 802.11 preambles. This step includes synchronizing the local clocks at multiple receivers with a reference clock, for example, using Synchronous Ethernet. A next step includes receiving IEEE 802.11 packets from a transmitter by at least three fixed receivers. A next step includes determining a phase offset between the local clock and any nearest cycle of a preamble in the received packets in each of the receivers. A next step includes locating the transmitter using each of the phase offsets.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.