LOCATION FINGERPRINTING FOR TRANSIT SYSTEMS

摘要

Methods, program products, and systems for building a location fingerprint database for a transit system are described. The transit system can be a subway system including underground train stations and routes where location determination using GPS signals is difficult or impossible. A sampling device can measure signals, e.g., radio frequency (RF) signals detected at the stations or on the routes. A location server can construct a location fingerprint for each of the stations and the routes. Each location fingerprint can represent expected signal measurements by a user device if the user device is located at the respective station or route. The location server can provide the location fingerprint to a user device for the user device to determine a location of the user device within the station or on the route.

主权项

1. A method comprising:
receiving, by one or more computer processors and from a sampling device, a plurality of sensor readings, each of the sensor readings corresponding to a reading of an attribute of an environment at a portion of a transit system, the portion comprising a station of the transit system or at least a portion of a route of the transit system; determining, from the sensor readings, an environment profile for the portion of the transit system, the environment profile comprising a distribution of frequency of a number of occurrences of each particular value among the sensor readings over values of the readings; determining, from the environment profile, a location fingerprint for the portion of the transit system, the location fingerprint comprising projected readings of sensors of a mobile device when the mobile device is located at the portion of the transit system; and providing the location fingerprint to a user device for determining a location of the user device when the user device is in the transit system.