Abstract: In one embodiment, Wi-Fi access point data is cached on a mobile client device in response to distances to WPS tile boundaries. The mobile client device identifies one or more Wi-Fi access points in range based on signals received by a Wi-Fi radio, and estimates its location utilizing the identified one or more Wi-Fi access points and Wi-Fi access point data of one or more Wi-Fi positioning system (WPS) tiles in a WPS tile store on the mobile client device. Based on the estimated location, the mobile client device determines it is within a threshold distance of a boundary of the one or more WPS tiles present in the WPS tile store and requests one or more new WPS tiles from a reference database of a remote server. Upon receipt, the one or more new WPS tiles are cached in the WPS tile store on the mobile client device.
Type:
Grant
Filed:
July 11, 2016
Date of Patent:
February 6, 2018
Assignee:
Shyhook Wireless, Inc.
Inventors:
Nicholas Brachet, Farshid Alizadeh-Shabdiz, Joel N. Nelson, Russel K. Jones
Abstract: A method of delta-encoding and compressing a table containing 6-byte MAC addresses is provided. The MAC addresses are sorted, a first MAC address is stored, and only the binary differences between succeeding MAC addresses are stored. A method of reading a delta-encoded and compressed MAC address table is provided. A first unencoded MAC address is read. The remaining MAC addresses are generated by successively adding stored binary differences to the result of the previous addition. A method of encoding and compressing a location table is provided. A reference latitude and longitude is selected and stored. The offsets from the reference latitude and longitude are stored for the remaining locations. A method of reading an encoded location table is provided. A stored reference latitude and longitude is read. Stored offsets are read and applied to the reference latitude and longitude to generate a set of latitude and longitude locations.