System and method for estimating the probability of movement of access points in a WLAN-based positioning system
AssigneeSkyhook Wireless, Inc.
InventorsFarshid Alizadeh-Shabdiz, Oleksiy Ignatyev
Life of this patent
Estimating the term…
Abstract
Methods of and systems for estimating the probability of movement of access points in a WLAN-based positioning system are provided. Disclosed are methods to quantify the probability that a particular location estimate of a mobile device made by a Wi-Fi based positioning system is correct to within an arbitrary accuracy. Implementations use observed access point cluster size, age information for access point location determination, and/or the probability that one or more access points detected by the mobile device have relocated based on historic information about the movement of a collection of access points to make the probability determinations.
Claims22
A method of estimating the likelihood of a Wi-Fi enabled device being located within an estimated geographical area, the method comprising:
- identifying at least one Wi-Fi access point in range of the Wi-Fi enabled device based on signals received by the Wi-Fi enabled device transmitted by the at least one Wi-Fi access point;
- consulting a reference database to determine for the at least one Wi-Fi access point from which signals were received a last-known estimated position of each of the at least one Wi-Fi access point and time information associated with each of said last known positions for describing the age of each said last-known position relative to other information in the reference database;
- estimating a likelihood that the at least one Wi-Fi access point has moved from its corresponding last-known position based on a number of Wi-Fi access points from which signals were received and the associated time information;
- and
- inferring the likelihood of the Wi-Fi enabled device being located within an estimated geographical area based, at least in part, on the likelihood that the at least one Wi-Fi access point has moved from its corresponding last-known position.
A method of estimating the likelihood of a Wi-Fi enabled device being located within an estimated geographical area, the method comprising:
- extracting information from signals received by the Wi-Fi enabled device transmitted by at least one Wi-Fi access point in range of the Wi-Fi enabled device, the signals identifying each of the at least one Wi-Fi access points from which signals were received;
- consulting a reference database to determine for at least one of the Wi-Fi access points from which signals were received a set of information identifying a corresponding set of Wi-Fi access points from which signals are expected to be received when the Wi-Fi enabled device receives signals from the at least one Wi-Fi access point of the plurality;
- and
- estimating the likelihood of the Wi-Fi enabled device being located within an estimated geographical area based on a comparison of the information identifying Wi-Fi access points from which signals were received, the number of Wi-Fi access points from which signals were received, and the set of information identifying the corresponding set of Wi-Fi access points from which signals are expected to be received.
A method of estimating the likelihood of a Wi-Fi enabled device being located within an estimated geographical area, the method comprising:
- extracting information from signals received by the Wi-Fi enabled device transmitted by a plurality of Wi-Fi access points in range of the Wi-Fi enabled device, the signals identifying each of the plurality of Wi-Fi access points which signals were received;
- consulting a reference database to determine if the identity of each of the plurality of the identified Wi-Fi access points from which signals were received are present in the reference database;
- estimating a likelihood that a Wi-Fi access points has moved from a corresponding last-known position based on the number of Wi-Fi access point from which signals were received and for which identities are present in the reference database and based on time information associated with the Wi-Fi access points from which signals were received for describing the age of the signals received from the Wi-Fi access points relative to other information in the reference database;
- and inferring the likelihood of the Wi-Fi enabled device being located within an estimated geographical area based on the likelihood that a Wi-Fi access point has moved from a corresponding last-known position.
Dependencies are inferred from the claim text.