Preferred system selection techniques for mobile terminals

• US 5,734,980 A
• Filed: 01/31/1995
• Issued: 03/31/1998
• Est. Priority Date: 01/31/1995
• Status: Expired due to Term

• Current Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Inventors: Collins, Daniel G., Hooper, Jeff Duwayne
• Primary Examiner(s): Urban, Edward F.
• Application Number:
  US08/381,105
• Time in Patent Office: 1,155 Days
• Field of Search: 455/33.1, 455/33.4, 455/54.1, 455/54.2, 455/56.1, 455/62, 455/166.1, 455/166.2, 455/432, 455/433, 455/434, 455/517, 455/524, 379/58, 379/59
• US Class Current: 455/434
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support

Abstract

Method for selecting a preferred system for wireless communications with a mobile terminal or subscriber. To select a preferred system for wireless communications with a mobile terminal or subscriber using a mobile terminal, a range of operating frequencies are scanned to detect wireless systems. Each time a wireless system is detected, a determination is made as to whether the detected wireless system is a most preferred system or a lesser preferred system for the mobile terminal or subscriber. If the detected wireless system is determined to be the most preferred system, scanning is terminated and the detected wireless system is selected for wireless. If, however, the detected wireless system is determined to be one of the lesser preferred systems, selection information for the detected wireless system is stored in a memory subsystem of the mobile terminal and scanning continues. Upon completion of the scanning, if no wireless system has been selected as the most preferred system, a highest ranking lesser preferred system is selected using the selection information stored in the memory subsystem for wireless communications.

Claims

1. For a mobile terminal having a memory subsystem, a method for selecting a preferred system for wireless communications therewith, comprising the steps of:

storing, in said memory subsystem of said mobile terminal, a system identifier and a rank for a most preferred system and each one of a plurality of lesser preferred systems;

scanning a range of operating frequencies to detect wireless systems operating within said range of frequencies;

each time a wireless system is detected during said scanning;

acquiring a system identifier for said detected wireless system;

comparing said acquired system identifier to said system identifier for said most preferred system;

if said acquired system identifier matches said system identifier for said most preferred system, determining that said detected wireless system is said most preferred system;

if said detected wireless system is determined to be said most preferred system for said mobile terminal, terminating said scanning and selecting said most preferred system for wireless communications with said mobile terminal;

comparing said acquired system identifier to said system identifier for said plurality of lesser preferred systems;

if said acquired system identifier matches said system identifier for one of said plurality of lesser preferred systems, determining that said detected wireless system is one of said plurality of lesser preferred systems for said mobile terminal and storing, in said memory subsystem of said mobile terminal, selection information which includes an operating frequency at which said detected wireless system transmits and said rank of said detected wireless system; and

upon completion of said scanning, if no detected wireless system has been determined to be said most preferred system for said mobile terminal, selecting, using said selection information stored in said memory subsystem, a highest ranking lesser preferred system for wireless communications with said mobile terminal;

and further comprising the steps of;

prior to scanning said range of operating frequencies, scanning a home frequency to detect wireless systems operating at said home frequency;

if a wireless system operating at said home frequency is detected, determining if said detected wireless system is a home system for said mobile terminal;

if said detected wireless system operating at said home frequency is determined to be said home system for said mobile terminal, selecting said home system for wireless communications with said mobile terminal;

if said detected wireless system operating at said home frequency is determined to not be said home system for said mobile terminal, determining if said detected wireless system operating at said home frequency is said most preferred system or one of said plurality of lesser preferred systems for said mobile terminal;

if said detected wireless system operating at said home frequency is determined to be said most preferred system for said mobile terminal, selecting said detected wireless system operating at said home frequency for wireless communications with said mobile terminal; and

if said detected wireless system operating at said home frequency is determined to be one of said plurality of lesser preferred systems for said mobile terminal, storing selection information for said detected wireless system operating at said home frequency in said memory subsystem of said mobile terminal.

2. For a mobile terminal having a memory subsystem and operable in at least one standard, a method for selecting a preferred system for wireless communications therewith, comprising the steps of:

storing, in said memory subsystem of said mobile terminal, a system identifier and a rank for a most preferred system and each one of a plurality of lesser preferred systems;

scanning a home frequency to detect wireless systems operating at said home frequency;

if a wireless system operating at said home frequency is detected, determining if said detected wireless system is operating in accordance with one of said at least one standard for said mobile terminal;

if said detected wireless system operating at said home frequency is determined to not be operating in accordance with one of said at least one standard for said mobile terminal, ignoring said detected wireless system not operating in accordance with one of said at least one standard for said mobile terminal;

if said detected wireless system operating at said home frequency is determined to be operating in accordance with one of said at least one standard for said mobile terminal, determining if said detected wireless system is a home system for said mobile terminal;

if said detected wireless system operating at said home frequency is determined to be said home system for said mobile terminal, selecting said home system for wireless communications with said mobile terminal;

if said detected wireless system operating at said home frequency is determined to not be said home system for said mobile terminal, determining if said detected wireless system operating at said home frequency is said most preferred system or one of said plurality of lesser preferred systems for said mobile terminal by acquiring a system identifier for said detected wireless system operating at said home frequency, comparing said acquired system identifier to said system identifier for said most preferred system, determining that said detected wireless system is said most preferred system if said acquired system identifier matches said system identifier for said most preferred system, comparing said acquired system identifier to said system identifier for said plurality of lesser preferred systems if said acquired system identifier fails to match said system identifier for said most preferred system and determining that said detected wireless system is one of said plurality of lesser preferred systems if said acquired system identifier matches said system identifier for one of said plurality of lesser preferred systems;

if said detected wireless system operating at said home frequency is determined to be said most preferred system for said mobile terminal, selecting said detected wireless system operating at said home frequency for wireless communications with said mobile terminal;

if said detected wireless system operating at said home frequency is determined to be one of said plurality of lesser preferred systems for said mobile terminal, storing an operating frequency at which said detected wireless system operating at said home frequency operates and said rank of said detected wireless system operating at said home frequency in said memory subsystem of said mobile terminal;

if said detected wireless system operating at said home frequency is determined to not be said home system or said most preferred system for said mobile terminal, scanning a range of operating frequencies to detect wireless systems operating within said range of frequencies;

each time a wireless system is detected during said scanning, determining if said detected wireless system is a most preferred system or one of a plurality of lesser preferred systems for said mobile terminal by determining if said detected wireless system is operating in accordance with one of said at least one standard for said mobile terminal, if said detected wireless system is determined to not be operating in accordance with one of said at least one standard for said mobile terminal, ignoring said detected wireless system not operating in accordance with said standard for said mobile terminal and continuing with said scanning of said range of frequencies, if said detected wireless system is determined to be operating in accordance with one of said at least one standard for said mobile terminal, acquiring a system identifier for said detected wireless system, comparing said acquired system identifier to said system identifier for said most preferred system, determining that said detected wireless system is said most preferred system if said acquired system identifier matches said system identifier for said most preferred system, comparing said acquired system identifier to said system identifier for said plurality of lesser preferred systems if said acquired system identifier fails to match said system identifier for said most preferred system and determining that said detected wireless system is one of said plurality of lesser preferred systems if said acquired system identifier matches said system identifier for one of said plurality of lesser preferred systems;

if said detected wireless system is determined to be said most preferred system for said mobile terminal, terminating said scanning and selecting said most preferred system for wireless communications with said mobile terminal;

if said detected wireless system is determined to be one of said plurality of lesser preferred systems for said mobile terminal, storing an operating frequency at which said detected wireless system transmits and said rank of said detected wireless system in said memory subsystem of said mobile terminal; and

upon completion of said scanning, if no detected wireless system has been determined to be said most preferred system for said mobile terminal, selecting, using said selection information stored in said memory subsystem, a highest ranking lesser preferred system for wireless communications with said mobile terminal.

3. A method for selecting a preferred system for wireless communications according to claim 2 wherein said mobile terminal is operable in a selected one of the GSM-based, IS-95 and IS-136 standards and wherein said system identifier for said most preferred system and each one of said plurality of lesser preferred systems is either a combined MCC/MNC value, a NID value or a PSID value.

4. A method for selecting a preferred system for wireless communications according to claim 2 wherein the step of scanning a range of operating frequencies further comprises the steps of:

scanning a first range of operating frequencies to detect cellular systems operating within said first range of frequencies; and

scanning a second range of operating frequencies to detect PCS systems operating within said second range of frequencies.

5. For a multiple subscriber mobile terminal having a memory subsystem and constructed to receive a user interface module having information stored therein, a method for subscriber selection of a preferred system for wireless communications between said preferred system and said multiple subscriber mobile terminal, comprising the steps of:

providing a user interface module having a home frequency, a range of frequencies, a system identifier for a most preferred system and each one of plurality of lesser preferred systems and a rank for said most preferred system and each one of said plurality of lesser preferred systems stored therein;

inserting said user interface module into said multiple subscriber mobile terminal to transfer, from said user interface module to said memory subsystem of said multiple subscriber mobile terminal, said home frequency, said range of frequencies, said system identifier for said most preferred system and each one of said plurality of lesser preferred systems and said rank for said most preferred system and each one of said plurality of lesser preferred systems;

scanning said range of operating frequencies to detect wireless systems operating within said range of frequencies;

each time a wireless system is detected during said scanning;

acquiring a system identifier for said detected wireless system;

comparing said acquired system identifier to said system identifier for said most preferred system;

if said acquired system identifier matches said system identifier for said most preferred system, determining that said detected wireless system is said most preferred system for said subscriber;

if said detected wireless system is determined to be said most preferred system for said mobile terminal, terminating said scanning and selecting said most preferred system for wireless communications with said multiple subscriber mobile terminal;

comparing said acquired system identifier to said system identifier for said plurality of lesser preferred systems;

if said acquired system identifier matches said system identifier for one of said plurality of lesser preferred systems, determining that said detected wireless system is one of said plurality of lesser preferred systems for said subscriber and storing, in said memory subsystem of said multiple subscriber mobile terminal, selection information which includes an operating frequency at which said detected wireless system transmits and said rank of said detected wireless system; and

upon completion of said scanning, if no detected wireless system has been determined to be said most preferred system for said subscriber, selecting, using said selection information stored in said memory subsystem, a highest ranking lesser preferred system for wireless communications with said multiple subscriber mobile terminal;

and further comprising the steps of;

prior to scanning said range of operating frequencies, scanning said home frequency to detect wireless systems operating at said home frequency;

if a wireless system operating at said home frequency is detected, determining if said detected wireless system is a home system for said subscriber;

if said detected wireless system operating at said home frequency is determined to be said home system for said subscriber, selecting said home system for wireless communications with said multiple subscriber mobile terminal;

if said detected wireless system operating at said home frequency is determined to not be said home system for said subscriber, determining if said detected wireless system operating at said home frequency is said most preferred system or one of said plurality of lesser preferred systems for said subscriber;

if said detected wireless system operating at said home frequency is determined to be said most preferred system for said subscriber, selecting said detected wireless system operating at said home frequency for wireless communications with said multiple subscriber mobile terminal; and

if said detected wireless system operating at said home frequency is determined to be one of said plurality of lesser preferred systems for said subscriber, storing selection information for said detected wireless system operating at said home frequency in said memory subsystem of said multiple subscriber mobile terminal.

6. For a mobile terminal having a memory subsystem, a method for selecting a preferred system for wireless communications therewith, comprising the steps of:

scanning a home frequency to detect wireless systems operating at said home frequency;

if a wireless system operating at said home frequency is detected, determining if said detected wireless system is a home system for said mobile terminal;

if said detected wireless system operating at said home frequency is determined to be said home system for said mobile terminal, selecting said home system for wireless communications with said mobile terminal;

if said detected wireless system operating at said home frequency is determined to not be said home system for said mobile terminal, determining if said detected wireless system operating at said home frequency is a most preferred system or one of a plurality of lesser preferred systems for said mobile terminal;

if said detected wireless system operating at said home frequency is determined to be said most preferred system for said mobile terminal, selecting said detected wireless system operating at said home frequency for wireless communications with said mobile terminal;

if said detected wireless system operating at said home frequency is determined to be one of said plurality of lesser preferred systems for said mobile terminal, storing selection information for said detected wireless system operating at said home frequency in said memory subsystem of said mobile terminal and scanning a range of operating frequencies to detect wireless systems operating within said range of frequencies;

each time a wireless system is detected during said scanning, determining if said detected wireless system is said most preferred system or one of said plurality of lesser preferred systems for said mobile terminal;

if said detected wireless system is determined to be said most preferred system for said mobile terminal, terminating said scanning and selecting said most preferred system for wireless communications with said mobile terminal;

if said detected wireless system is determined to be one of said plurality of lesser preferred systems for said mobile terminal, storing selection information for said detected wireless system in said memory subsystem of said mobile terminal; and

upon completion of said scanning, if no detected wireless system has been determined to be said most preferred system for said mobile terminal, selecting, using said selection information stored in said memory subsystem, a highest ranking lesser preferred system for wireless communications with said mobile terminal.

7. For a multiple subscriber mobile terminal having a memory subsystem and constructed to receive a user interface module having information stored therein, a method for subscriber selection of a preferred system for wireless communications between said preferred system and said multiple subscriber mobile terminal, comprising the steps of:

providing a user interface module having a home frequency, a system identifier for a most preferred system and each one of a plurality of lesser preferred systems and a rank for said most preferred system and each one of said plurality of lesser preferred systems stored therein;

inserting said user interface module into said multiple subscriber mobile terminal to transfer, from said user interface module to said memory subsystem of said multiple subscriber mobile terminal, said home frequency, said system identifier for said most preferred system and each one of said plurality of lesser preferred systems and said rank for said most preferred system and each one of said plurality of lesser preferred systems;

scanning said home frequency to detect wireless systems operating at said home frequency;

if a wireless system operating at said home frequency is detected, determining if said detected wireless system is a home system for said subscriber;

if said detected wireless system operating at said home frequency is determined to be said home system for said subscriber, selecting said home system for wireless communications with said multiple subscriber mobile terminal;

if said detected wireless system operating at said home frequency is determined to not be said home system for said subscriber, determining if said detected wireless system operating at said home frequency is said most preferred system or one of said plurality of lesser preferred systems for said subscriber;

if said detected wireless system operating at said home frequency is determined to be said most preferred system for said subscriber, selecting said detected wireless system operating at said home frequency for wireless communications with said multiple subscriber mobile terminal;

if said detected wireless system operating at said home frequency is determined to be one of said plurality of lesser preferred systems for said subscriber, storing selection information for said detected wireless system operating at said home frequency in said memory subsystem of said multiple subscriber mobile terminal and scanning a range of operating frequencies to detect wireless systems operating within said range of frequencies;

each time a wireless system is detected during said scanning, determining if said detected wireless system is said most preferred system or one of said plurality of lesser preferred systems for said subscriber;

if said detected wireless system is determined to be said most preferred system for said subscriber, terminating said scanning and selecting said most preferred system for wireless communications with said multiple subscriber mobile terminal;

if said detected wireless system is determined to be one of said plurality of lesser preferred systems for said subscriber, storing selection information for said detected wireless system in said memory subsystem of said multiple subscriber mobile terminal; and

upon completion of said scanning, if no detected wireless system has been determined to be said most preferred system for said subscriber, selecting, using said selection information stored in said memory subsystem, a highest ranking lesser preferred system for wireless communications with said multiple subscriber mobile terminal.