Estimation of speed and direction of travel in a WLAN positioning system

• US 8,090,386 B2
• Filed: 11/12/2010
• Issued: 01/03/2012
• Est. Priority Date: 05/08/2006
• Status: Active Grant

• Current Assignee: Skyhook Wireless Incorporated (Liberty Broadband Corp.)
• Original Assignee: Skyhook Wireless Incorporated (Liberty Broadband Corp.)
• Inventors: Alizadeh-Shabdiz, Farshid, Morgan, Edward James, Pahlavan, Kaveh
• Primary Examiner(s): DOAN, KIET M
• Application Number:
  US12/945,266
• Publication Number:
  US 20110058495A1
• Time in Patent Office: 417 Days
• Field of Search: 455/456, 455/456.5, 455/456.1, 455/456.2, 455/522, 455/515, 455/438, 455/436, 455/418, 455/404.2, 455/440, 455/441, 342/387, 342/457, 370/338, 370/328, 370/332, 370/295
• US Class Current: 455/456.1
• CPC Class Codes: G01S 11/02 using radio waves G01S19/00 takes precedence
• CPC Class Codes: G01S 11/06 using intensity measurements
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/027 using movement velocity, acceleration information
• CPC Class Codes: H04W 64/006 with additional information processing, e.g. for direction or speed determination

Abstract

A method for estimating the speed and bearing of a Wi-Fi enabled device using WLAN radio signals in a WLAN based location service is provided. A method used to estimate a speed of travel of a Wi-Fi enabled device comprises the Wi-Fi enabled device receiving signals transmitted by Wi-Fi access points in range of the Wi-Fi enabled device, and using the signals to estimate the speed of and/or direction of travel of the Wi-Fi enabled device.

Claims

1. A method of estimating a speed of travel of a Wi-Fi enabled device without requiring position estimates of the Wi-Fi enabled device, the method comprising:

the Wi-Fi enabled device receiving signals transmitted by at least one Wi-Fi access point in range of the Wi-Fi enabled device, the receiving occurring over time;

measuring at least one amount of time during which the Wi-Fi enabled device detects signals transmitted by the at least one Wi-Fi access point;

determining at least one interval of time based on the at least one amount of time during which the Wi-Fi enabled device detects signals transmitted by the at least one Wi-Fi access point; and

estimating the speed of travel of the Wi-Fi enabled device based on the at least one interval of time, so that the speed of travel of the Wi-Fi enabled device can be estimated without requiring position estimates of the Wi-Fi enabled device.

2. The method of claim 1, wherein the length of time is determined over a given duration of time, or it is calculated during a limited window of time.

3. A system for estimating a speed of travel of a Wi-Fi enabled device without requiring position estimates of the Wi-Fi enabled device, the system comprising:

a computer readable medium including instructions that when executed cause a computer system to;

measure at least one amount of time during which the Wi-Fi enabled device detects signals transmitted by at least one Wi-Fi access point in range of the Wi-Fi enabled device;

determine at least one interval of time based on the at least one amount of time during which the Wi-Fi enabled device detects signals transmitted by the at least one Wi-Fi access point; and

estimate the speed of travel of the Wi-Fi enabled device based on the at least one interval of time, so that the speed of travel of the Wi-Fi enabled device can be estimated without requiring position estimates of the Wi-Fi enabled device.

4. The system of claim 3, wherein the length of time is determined over a given duration of time, or it is calculated during a limited window of time.