Method and apparatus for increasing a probability that a dual-band mobile station will acquire a desired autonomous system

• US 6,229,996 B1
• Filed: 12/12/1997
• Issued: 05/08/2001
• Est. Priority Date: 12/12/1997
• Status: Expired due to Fees

• Current Assignee: Nokia Mobile Phones UK Limited (Nokia Corporation)
• Original Assignee: Nokia Mobile Phones UK Limited (Nokia Corporation)
• Inventors: Uistola, Ari
• Primary Examiner(s): Chang, Vivian
• Assistant Examiner(s): MEHRPOUR, NAGHMEH
• Application Number:
  US08/990,043
• Time in Patent Office: 1,243 Days
• Field of Search: 455/552, 455/553, 455/150.1, 455/180.1, 455/186.1, 455/168.1, 455/188.1, 455/513, 455/515, 455/434, 455/458, 455/161.3
• US Class Current: 455/168.1
• CPC Class Codes: H04B 1/00 Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
• CPC Class Codes: H04B 1/406 with more than one transmission mode, e.g. analog and digital modes
• 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 8/183 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 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A method for operating a dual-band mobile station (10) includes a first step of (a) storing information in the mobile station. The stored information includes an ordered list of frequency bands (Band Order Table 24A). For example, at least one frequency band is an 800 MHz frequency band and at least one other frequency band is a 1900 MHz frequency band. The stored information further includes an identity (24B) of a band wherein an acceptable control channel was last located. A next step (b) is executed in response to a user invoking a search procedure to locate a new non-public system. This step accesses the memory to determine the identity of the band wherein an acceptable control channel was last located, and marks this band as a band to be searched. A next step (c) collects signal strength measurements on channels in the band to be searched and executes a channel search procedure to locate a control channel of a desired non-public system within the band to be searched. If a desired non-public system is not located in the band to be searched, a next step (d) accesses the memory to obtain a next band to be searched from the Band Order Table. The method repeats steps (c) and (d) until either the ordered list of frequency bands is exhausted or a desired non-public system is located, thereby enabling a non-public system to be located in a band other than the current band of the mobile station.

Claims

1. A method for operating a mobile station, comprising steps of:

(a) storing information in a memory of the mobile station, the stored information comprising an ordered list of frequency bands, each frequency band comprising at least one frequency channel, the stored information further comprising an identity of a band wherein an acceptable control channel was last located;

(b) in response to a user invoking a search procedure to locate a new non-public system, accessing the memory to determine the identity of the frequency band wherein an acceptable control channel was last located, and marking the frequency band wherein the acceptable control channel was last located as a band to be searched;

(c) collecting signal strength measurements on frequency channels in the frequency band to be searched and executing a channel search procedure to locate a control channel of a desired non-public system within the frequency band to be searched;

(d) if a desired non-public system is not located in the frequency band to be searched, accessing the memory to obtain a next band to be searched from the ordered list of frequency bands and marking the next band as the frequency band to be searched; and

repeating steps (c) and (d) until either the ordered list of frequency bands is exhausted or a desired non-public system is located.

2. A method as in claim 1, wherein the desired non-public system is one of a Residential system or a Private system.

3. A method as in claim 1, wherein the control channel is a digital control channel (DCCH).

4. A method as in claim 1, wherein at least one frequency band is an 800 MHz frequency band, and wherein at least one other frequency band is a 1900 MHz frequency band.

5. A method as in claim 1, wherein if the step of accessing the memory to determine the identity of the frequency band wherein an acceptable control channel was last located is not successful, the method instead includes a step of accessing the memory to obtain a predetermined frequency band to be searched from the ordered list of frequency bands and marking the predetermined frequency band as the frequency band to be searched.

6. A method as in claim 5, wherein the predetermined frequency band is the first band in the ordered list of frequency bands.

7. A method as in claim 1, wherein the step of storing information is accomplished in cooperation with a user interface of the mobile station.

8. A method as in claim 1, wherein the step of storing information is accomplished by receiving the information over the air from a remote location.

9. A mobile station, comprising:

a RF transceiver for bidirectionally communicating with base stations of public or autonomous communications systems;

a user interface for displaying information to a user and for receiving an input from a user;

a memory for storing information, the stored information comprising an ordered list of frequency bands, each frequency band comprising at least one frequency channel, the stored information further comprising an identity of a band wherein an acceptable control channel was last located; and

a controller coupled to said transceiver, to said user interface, and to said memory, said controller being responsive to a user invoking a search procedure to locate a new non-public system for accessing said memory to determine the identity of the frequency band wherein an acceptable control channel was last located, and for marking the frequency band wherein the acceptable control channel was last located as a frequency band to be searched, said controller tuning said transceiver for collecting signal strength measurements on frequency channels in the frequency band to be searched and executing a channel search procedure to locate a control channel of a desired non-public system within the frequency band to be searched, said controller being responsive to a condition that a desired non-public system is not located in the frequency band to be searched, for accessing said memory to obtain a next frequency band to be searched from said ordered list of frequency bands and for marking the next frequency band in said ordered list as the frequency band to be searched, said controller continuing to collect signal strength measurements and executing the search procedure until either the ordered list of frequency bands is exhausted or a desired non-public system is located.

10. A mobile station as in claim 9, wherein the desired non-public system is one of a Residential system or a Private system.

11. A mobile station as in claim 9, wherein the control channel is a digital control channel (DCCH).

12. A mobile station as in claim 9, wherein at least one frequency band is an 800 MHz frequency band, and wherein at least one other frequency band is a 1900 MHz frequency band.

13. A mobile station as in claim 9, wherein said controller is responsive to a condition wherein accessing said memory to determine the identity of the frequency band wherein an acceptable control channel was last located is not successful, for instead accessing said memory to obtain a predetermined frequency band to be searched from the ordered list of frequency bands and for marking the predetermined frequency band as the frequency band to be searched.

14. A mobile station as in claim 13, wherein said predetermined frequency band is the first band in the ordered list of frequency bands.

15. A mobile station as in claim 9, wherein at least a portion of said ordered list of frequency bands is stored in said memory in cooperation with said user interface.

16. A mobile station as in claim 9, wherein at least a portion of said ordered list of frequency bands is stored in said memory by receiving information over the air from a remote location.

17. A method for operating a mobile station, comprising steps of:

(a) storing information in a memory of the mobile station, the stored information comprising a list having a plurality of entries, each entry corresponding to a frequency band comprising at least one frequency channel, the stored information further comprising an identity of a frequency band wherein an acceptable digital control channel (DCCH) was last located;

(b) in response to a search procedure being invoked to locate a desired one of a Residential system or a Private system, accessing the memory to determine the identity of the a frequency band wherein the acceptable DCCH was last located, and marking the frequency band as a frequency band to be searched, else if the identity of the frequency band wherein the acceptable DCCH was last located is not available, then selecting a predetermined entry in the list of frequency bands and marking the corresponding frequency band as the frequency band to be searched;

(c) collecting signal strength measurements on frequency channels in the frequency band to be searched and executing a channel search procedure to locate a control channel of a desired Residential system or Private system within the frequency band to be searched;

(d) if a desired Residential system or Private system is not located in the frequency band to be searched, accessing the memory to obtain a next entry from the list of frequency bands and marking the corresponding frequency band as the frequency band to be searched; and

repeating steps (c) and (d) until either the list of frequency band s is exhausted or the desired Residential system or Private system is located.

18. A method as in claim 17, wherein at least one frequency band is an 800 MHz frequency band, and wherein at least one other frequency band is a 1900 MHz frequency band.

19. A method as in claim 17, wherein the step of storing information includes a step of inputting information for at least one of adding an entry to the list, deleting an entry from the list, or re-ordering entries in the list.

20. A method as in claim 19, wherein the inputted information is received at least in part from one of a user interface of the mobile station or from a remote location.

21. A method for operating a mobile station, comprising steps of:

(a) storing information in a memory of the mobile station, the stored information comprising a list having a plurality of entries, each of said plurality entries corresponding to a band of frequencies comprising a plurality of frequency channels;

(b) in response to a search procedure being invoked to locate a desired one of a Non-Public wireless system, specifically one of a Residential wireless system or a Private wireless system, accessing a first entry of the list to determine a first band of frequencies to be searched for the desired one of the Residential wireless system or the Private wireless system;

(c) executing a search procedure in the band of frequencies being searched in an attempt to locate a control channel of the desired one of the Residential wireless system or the Private wireless system within the band of frequencies being searched;

(d) if the control channel of the desired one of the Residential wireless system or the Private wireless system is not located within the band of frequencies being searched, accessing a next entry in the list to determine a next band of frequencies to be searched for the desired one of the Residential wireless system or the Private wireless system; and

repeating steps (c) and (d) until either all of the entries of the list have been accessed or the control channel of the desired one of the Residential wireless system or the Private wireless system is located.

22. A method as in claim 21, wherein one said plurality of entries comprises an identity of a band of frequencies wherein an acceptable control channel was last located.