Method for allowing a mobile phone to receive a call through a wireless network for which it is not registered, for emergency purposes

US5864755A · kind A · utility

Assignee

• Siemens Business Communication Systems, Inc. · US

Inventors

• Neal J. King · Munich, DE
• Markku Korpi · Starnberg, DE
• Günter Kleindl · Ybbs an der Donau, AT
• Ernst Horvath · Wien, AT
• Wilhelm Mueller · Nieheim, DE

Key dates

• Filing date: Jun 11, 1996
• Grant date: Jan 26, 1999
• Expiry date: Jun 11, 2016

Classification

• Technology area (CPC H): Electricity
• CPC primary: H04M2242/04
• WIPO field: Telecommunications
• WIPO sector: Electrical engineering

Abstract

A method for operating a wireless telephone system to provide emergency service for a wireless telephone operating in the wireless telephone system. In the present invention, the wireless telephone system receives a request to connect the wireless phone to a predetermined telephone number from the wireless telephone. The telephone system then queries the wireless telephone for a unique identifying number identifying the wireless telephone. The unique identifying number enables the wireless telephone system to connect the wireless telephone to the wireless telephone system. The wireless telephone system maintains a set of direct inward dialing numbers (DIDs) that are used exclusively for emergency calls. Each of the DID allows a caller outside of the wireless telephone system to direct a call to a telephone within the wireless telephone system. The emergency call is assigned one of these DIDs and that DID is linked to the unique identifying number of the telephone placing the emergency call. The wireless telephone is then connected to an emergency operator and the emergency operator is given the assigned DID. The DID enables a call from the emergency operator to the wireless telepho…