Extended home indentification being used by the same service provider as a home identification in a service area other than the home service area for cellular radio telephone systems

• US 5,463,675 A
• Filed: 02/10/1994
• Issued: 10/31/1995
• Est. Priority Date: 06/17/1991
• Status: Expired due to Term

• Current Assignee: AT&T IPM Corp. (AT&T, Inc.)
• Original Assignee: AT&T IPM Corp. (AT&T, Inc.)
• Inventors: Gerszberg, Irwin
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): CUMMING, WILLIAM D
• Application Number:
  US08/195,980
• Time in Patent Office: 628 Days
• Field of Search: 379/56, 379/58, 379/59, 379/60, 379/63, 379/131, 379/140, 455/31.1, 455/33.1, 455/34.1, 455/15, 455/54.1
• US Class Current: 455/551
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 4/00 Services specially adapted for wireless communication networks; Facilities therefor
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 76/10 Connection setup
• CPC Class Codes: H04W 8/183 Processing at user equipment or user record carrier
• CPC Class Codes: H04W 8/22 Processing or transfer of terminal data, e.g. status or physical capabilities
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems

Abstract

Transitions of a mobile radiotelephone between operating on A band service and B band service are controlled to enable the mobile radiotelephone to utilize the bands of a single service provider over a wide area of cellular service areas in which service is provided on either A or B bands by that single service provider. Each mobile radiotelephone served by a single service provider has an extended home system identification entered into its number assignment module (NAM). When the mobile radiotelephone is operating in a roam mode it scans both the A and B bands searching for the extended home system identification. If the system is successful in locking onto one of the extended home system identification channels the mobile radiotelephone uses that setup channel to establish and receive calls from its original service provider within the present service area. If the lockup can not be made the mobile radiotelephone uses the system I.D. and the A or B band as normally set in the NAM.

Claims

1. In a cellular mobile radio telephone communications system having A band and B band frequencies in each service area and in which a service provider is assigned one of the A band and B band of frequencies in a home service area and another different one of the A band and B band of frequencies in a service area other than the home service area, a method for predisposing a mobile radiotelephone to select service from the same service provider in the home service area and the service area other than the home service area, comprising the steps of:

storing in the number assignment of the mobile radiotelephone a home identification number and at least one extended home identification number, the extended home identification being used by the same service provider as a home identification in the service area other than the home service area;

operating the mobile radiotelephone to set up a call;

determining if the operating mobile radiotelephone is located in a service area other than the home service area by determining if the home identification number is operative;

searching overhead/control channels of both the A and B band of frequencies if the home identification number is not operative for use as the extended home identification number,

the mobile radio telephone locking onto a channel provided by the same service provider containing the extended home identification number;

the mobile radiotelephone in response to locking operating in a home mode using its home mode telephone number and establishing a call in the service area other than the home area with the service provider used in the home service area.

2. In a cellular mobile radio telephone communications system having A and B band frequencies in each service area and in which a service provider is assigned one of the A band and B band of frequencies in a home service area and another one of the A band and B band of frequencies in a service area other than the home service area, mobile radiotelephone apparatus predisposed to select service from the same service provider in the home service area and the service area other than the home service area, comprising:

the mobile radiotelephone apparatus including radio equipment and apparatus for operating the mobile radiotelephone apparatus;

and including memory having a number assignment module for storing identification numbers of the service provider used in the home service area and at least an extended home identification code used by the service provider as a home identification code in a service area other than the home service area;

a controller for controlling a frequency of operation of the mobile radiotelephone apparatus, including;

a central processing unit connected for comparing identification codes received via the radio equipment on control channels with the stored home identification code and the extended home identification code and when in a service area other than the home service area responding to the extended home identification code to select service from the service provider serving the home service area and operating in a home mode of operation using its home mode telephone number and selecting a frequency band for operation of the radio equipment based on receipt of the extended home identification code on a control channel of the service area other than the home service area.