Cellular network acquisition method and apparatus

• US 7,620,395 B2
• Filed: 11/18/2003
• Issued: 11/17/2009
• Est. Priority Date: 11/19/2002
• Status: Expired due to Fees

• Current Assignee: Lenovo Innovations Ltd Hong Kong (Lenovo Group Ltd.)
• Original Assignee: NEC Corporation
• Inventors: Gabin, Frederic, Legg, Nigel, Downer, Darioush, Ormson, Richard, Yamashita, Osamu
• Primary Examiner(s): Kincaid; Lester
• Assistant Examiner(s): SHEDRICK, CHARLES TERRELL
• Application Number:
  US10/714,672
• Publication Number:
  US 20040229610A1
• Time in Patent Office: 2,191 Days
• Field of Search: 455/434, 455/34, 455/67.11
• US Class Current: 455/434
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

The present invention provides for a cellular communications device comprising determining a most suitable cell based on a characteristic of signals received from a plurality of cells, the signals from each cell being provided over a band of frequencies, and the said determination comprising the steps of taking a series of measurements of the said characteristics for each frequency so as to obtain an average value, wherein each measurement in the said series is taken for all of the frequencies in the said band before the next measurement in the series is taken, and the said series of measurements on each frequency are equally spaced and serve to provide equal intervals therebetween for further processing of signals from network cells.

Claims

1. A method of determining a most suitable cell during network acquisition for a cellular communications device, based on a characteristic of signals received from a plurality of cells, the signals from each cell being provided over a band of frequencies, said method comprising:

taking a series of measurements of said characteristics by said cellular communication device for each frequency of a first frequency band, so as to obtain an average measurement value of said characteristic for each frequency of said first frequency band, wherein the series of measurements on said first frequency band are equally spaced in time, with equal time intervals therebetween; and

during the time intervals between measurements for said first frequency band, taking a series of measurements of said characteristic for each frequency of a second frequency band, wherein said first and second frequency bands operate in different operating modes, wherein said series of measurements on said first frequency band that is equally spaced in time is repeated a predetermined number of times to calculate said average measurement for each said frequency, wherein, before a completion of said predetermined number of times occurs and before said average measurement value is obtained, a second stage search operation processing is initiated for at least one detected strong signal.

2. A method as claimed in claim 1 wherein one operating mode comprises GSM, and the other operating mode comprises UMTS.

3. A cellular communications device including means for determining a most suitable cell during network acquisition for a cellular communications device, based upon a characteristic of signals received from a plurality of cells, the signals from each cell being provided over a band of frequencies, said cellular communications device comprising:

a first unit for taking a series of measurements of said characteristics for each frequency of a first frequency band, so as to obtain an average measurement value of the characteristic for each frequency of the first frequency band, wherein the series of measurements on the first frequency band are equally spaced in time, with equal time intervals therebetween; and

a second unit for taking a series of measurements of the characteristic for each frequency of a second frequency band during the time intervals between measurements for the first frequency band, wherein said first and second frequency bands operate in different operating modes, wherein said first unit and said second unit take said series of measurements on said first frequency band and said second frequency band a predetermined number of times to calculate said average measurement for each said frequency in said first frequency band, wherein before a completion of said predetermined number of times occurs and before said average measurement value is obtained, a second stage search operation processing is initiated for at least one detected strong signal.

4. A device as claimed in claim 3 wherein one operating mode comprises GSM, and the other operating mode comprises UMTS.

5. A method of determining a most suitable cell and a most suitable mode for a cellular communication device capable of operating in at least two modes, each operating mode having a plurality of frequencies occupying a frequency band, said method comprising:

selectively, for each time period of a predetermined number of successive time periods, said cellular communication device sequentially taking measurements of a characteristic for each frequency of each frequency band for each operating mode said cellular communication device is capable, each said time period being equal in time;

calculating an average value of said characteristic for each frequency of each frequency band; and

selecting said most suitable cell and said most suitable mode based upon said average values, wherein, before a completion of said predetermined number of times occurs and before said average measurement value is obtained, a second stage search operation processing is initiated for at least one detected strong signal wherein before a completion of said predetermined number of times occurs and before said average measurement value is obtained, a second stage search operation processing is initiated for at least one detected strong signal.

6. The method of claim 5, wherein said characteristic comprises a signal strength.

7. The method of claim 5, wherein one operating mode comprises GSM and another operating mode comprises UMTS.