US 8219061

Patent Overview — US8219061B1

Title: Method and system for obtaining emergency caller location
Patent number: US8219061B1
Application number: US13/206,522
Filing date: 2011-08-10
Publication (grant) date: 2012-07-10
Prior art date / priority date: 2005-07-14 (described in the source as an assumption, not a legal conclusion)
Inventor(s): Chi Fai Ho; Shin Cheung Simon Chiu
Original assignee: TP Lab Inc.
Current assignee (per source, which notes listed assignees may be inaccurate): Lab Technology LLC
Status: Active; anticipated expiration listed as 2027-05-17
Source: https://patents.google.com/patent/[US8219061](/patent/US8219061)/en

Purpose
The patent relates generally to telecommunications, and more specifically to providing location information for voice calls. The excerpt frames the problem through emergency calling: in traditional residential telephone service, a service provider assigns a telephone number, allocates an access line, and records the telephone number and subscription location (typically the street address) in an Automatic Location identity (ALI) database, which a 911 selective router and Public Safety Answering Point (PSAP) use to locate and dispatch emergency services. That assumption breaks down for VoIP service, because an IP telephone can be connected at a home gateway, a neighbor's cable modem gateway, or a hotel network, so the caller's actual location may differ from the registered subscription location.

Plain-language scope (from the excerpt)
Embodiments include systems and methods for obtaining a caller's location during a telephone call. A phone system obtains the subscriber access line identity of a subscriber access line and sends it to a subscriber location query system, which returns a subscriber location or subscriber location record. Subscriber phone equipment or a phone can store a subscriber access line identity; the stored identity can be used to retrieve the subscriber location record, comparing known-location data against identities obtained during calls to determine whether the subscriber phone equipment has changed location. Emergency call capabilities of a subscriber access line are determined by an emergency call test module sending a test signal or query.

What the excerpt does not establish
The supplied text is explicitly marked as an excerpt with omitted portions. It supplies no claim language, no complete written description, and no figures. It does not establish the full claimed scope, the specific test signal or query contents, or the detailed operation of the location query system.