Neighborhood cordless service call handoff

• US 7,738,872 B1
• Filed: 04/18/2006
• Issued: 06/15/2010
• Est. Priority Date: 12/30/1998
• Status: Expired due to Fees

• Current Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Original Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Inventors: Chow, Albert, Wang, Spencer, Ying, Wenchu, Kim, Jinman
• Primary Examiner(s): Ly; Nghi H
• Application Number:
  US11/405,820
• Time in Patent Office: 1,519 Days
• Field of Search: 455/436, 455/442, 455/435.1, 455/450, 455/552.1, 455/426.1, 455/462, 455/465, 370/331
• US Class Current: 455/436
• CPC Class Codes: H04W 36/00835 Determination of neighbour cell lists
• CPC Class Codes: H04W 84/16 WPBX [Wireless Private Branch Exchange]

Abstract

A method and apparatus for providing telephone call hand offs between a local cordless service and a different wireless cellular service such as a macro-cellular service. The local cordless service may be configured such that a mobile telephone equipped subscriber may place or receive calls for a fixed rate, for example, per month without having to pay radio frequency air time charges any time they are located within their selected subscribed-to zones. If the subscribed-to zones are adjacent to one another and the mobile subscriber roams from one zone to another, the subscriber may continue their free call uninterrupted and without paying air time charges. However, when the subscriber roams outside their subscribed-to zones they may be switched from the present local cordless services to conventional personal communications services and pay air time charges. However for an active call, no air-time charges are incurred as the user transitions between the cellular/DPCS environment and the local cordless service environment. Associated apparatus comprises an IBS for automatically changing radio frequency channels as the subscriber roams within a subscribed-to neighborhood zone, roams to another subscribed-to zone or roams outside a subscribed-to zone. Subscribers may choose to use their mobile identification number, their current directory telephone number for wired public switched telephone service or obtain a new directory number.

Claims

1. A telephony system configured to handoff a mobile station between a local cordless network and a cellular network, the system comprising:

a local cordless system comprising a plurality of radio transmitters, a network server platform, and a local digital switch coupled between the plurality of radio transmitters and the network server platform; and

a cellular system comprising a plurality of cellular base stations coupled to a mobile switching center, said mobile switching center coupled between the plurality of cellular base stations and the local digital switch,

wherein each of the plurality of radio transmitters is configured to communicate with the network server platform to request a hand-off of the mobile station from the radio transmitter, and the network server platform is configured to communicate with the mobile switching center to request a hand-off of the mobile station to one of the cellular base stations in response to said request for a hand-off of the mobile station from the radio transmitter.

2. The telephony system of claim 1, wherein the network server platform is configured to communicate with the mobile switching center using IS-41 protocol.

3. The telephony system of claim 1, further comprising a remote digital terminal coupled between the plurality of radio transmitters and the local digital switch.

4. The telephony system of claim 1, wherein each of the plurality of radio transmitters serves a zone located within an area served by the cellular network.

5. A local cordless system configured to handoff a mobile station between the local cordless system and a cellular system, the cellular system having a mobile switching center coupled to a plurality of cellular base stations, the local cordless system comprising:

a plurality of radio transmitters each for serving the mobile station within a respective zone;

a server; and

a local digital switch coupled between the plurality of radio transmitters and the server and configured to switch a connection of a local cordless system subscriber; and

wherein the server is configured to communicate with the mobile switching center in order to handoff the mobile station between one of the radio transmitters of the local cordless system and one of the cellular base stations.

6. The local cordless system of claim 5, wherein the server is configured to communicate with the mobile switching center using IS-41 protocol in order to perform the handoff.

7. The local cordless system of claim 5, wherein the server is configured to receive a signal from the mobile station through one of the radio transmitters indicating an impending handoff, and in response to receipt of said signal to communicate with the mobile switching center in order to handoff the mobile station from one of the radio transmitters to one of the cellular base stations.

8. The local cordless system of claim 5, wherein the server is configured to receive a signal from the mobile switching center indicating an impending handoff, and in response to receipt of said signal to communicate with the mobile station in order to handoff the mobile station to one of the radio transmitters.