Radio communication apparatus connected with a base station used in a service area prior to the others

• US 5,854,980 A
• Filed: 03/16/1995
• Issued: 12/29/1998
• Est. Priority Date: 03/18/1994
• Status: Expired due to Term

• Current Assignee: Fujitsu Mobile Communications Limited (Fujitsu Limited)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Takahashi, Shinya, Tomioka, Munehisa
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): Nguyen, Lee
• Application Number:
  US08/405,204
• Time in Patent Office: 1,384 Days
• Field of Search: 455/33.1, 455/33.2, 455/33.4, 455/34.1, 455/34.2, 455/54.1, 455/56.1, 455/161.1, 455/434, 455/515, 455/516, 455/435, 455/448, 455/455, 455/450, 379/59, 379/60, 379/63, 370/350, 370/324
• US Class Current: 455/434
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 76/10 Connection setup
• CPC Class Codes: H04W 8/183 Processing at user equipment or user record carrier

Abstract

A radio communication apparatus communicates with a base station in a home service area over a paging channel during a standby state for awaiting a call origination or a call reception. Responsive to the call origination or the call reception, the apparatus selects an access channel coincident with the paging channel and communicates with the base station over the access channel for the call origination or the call reception.

Claims

1. A radio communication apparatus for use in a radio communication system, wherein a plurality of radio channels in a predetermined band of frequencies include a first group of channels used while awaiting a call origination or a call reception and a second group of channels used in response to the call origination or the call reception, the system including a plurality of service areas, each of the service areas being assigned a system identification number which is broadcast by one or more base stations over at least one of the radio channels, the radio communication apparatus comprising:

storing means for storing at least one stored system identification number corresponding to at least one of the service areas;

receiving means for receiving a plurality of signals, each of the signals being transmitted over at least one of the radio channels, each of the signals including a system identification number;

first selecting means for selecting one of the channels of the first group, the first selecting means including

first listing means for listing at least two of the channels of the first group over which at least one of the signals are received by the receiving means,

first comparing means for comparing the stored system identification number with the system identification numbers included in the signals received over the channels listed by the first listing means, and

first channel selecting means for selecting one of the channels listed by the first listing means when the first comparing means determines a coincidence between the stored system identification number and the system identification number included in the signals received over the channel; and

second selecting means for selecting one of the channels of the second group, the channel of the second group selected by the second selecting means being a channel over which signals are received by the receiving means, the second selecting means including

second listing means for listing at least two of the channels of the second group over which at least one of the signals are received by the receiving means,

second comparing means for comparing the channel selected by the first channel selecting means with the channels listed by the second listing means, and

second channel selecting means for selecting one of the channels listed by the second listing means when the second comparing means determines a coincidence between the channel selected by the first channel selecting means and one of the channels listed by the second listing means,

and wherein the channel selected by the second selecting means is used for the call origination or the call reception.

2. The radio communication apparatus according to claim 1, wherein the signals received over the channel selected by the first selecting means have an electric field intensity greater than a predetermined electric field intensity.

3. The radio communication apparatus according to claim 1, wherein the signals received over each channel listed by the first listing means have an electric field intensity greater than a first predetermined electric field intensity.

4. The radio communication apparatus according to claim 1, wherein the signals received over each channel listed by the second listing means have an electric field intensity greater than a second predetermined electric field intensity.

5. A radio communication apparatus for use in a radio communication system, wherein a plurality of radio channels in a predetermined band of frequencies include a first group of channels used for initializing operation of the apparatus, a second group of channels used while awaiting a call origination or a call reception, and a third group of channels having at least one channel in common with each of the first and second groups of channels, the third group of channels being used in response to the call origination or the call reception, the system including a plurality of service areas, each of the service areas being assigned a system identification number which is broadcast by one or more base stations over at least one of the radio channels, the radio communication apparatus comprising:

storing means for storing at least one stored system identification number corresponding to a service area;

receiving means for receiving a plurality of signals, each of the signals being transmitted over at least one of the radio channels, each of the signals including a system identification number;

listing means for listing at least one of the channels of the first group, wherein the system identification number included in the signals transmitted over each channel listed by the listing means coincides with the stored system identification number;

first selecting means for selecting one of the channels of the second group from the channels listed by the listing means, the channel of the second group selected by the first selecting means being a channel over which signals are received by the receiving means; and

second selecting means for selecting one of the channels of the third group, the channel selected by the second selecting means being coincident with the channel of the second group selected by the first selecting means, the channel of the third group selected by the second selecting means being a channel over which signals are received by the receiving means,

and wherein the channel selected by the second selecting means is used for the call origination or the call reception.

6. The radio communication apparatus according to claim 5, wherein the signals received over each channel listed by the listing means have an electric field intensity greater than a predetermined field intensity.

7. A radio communication apparatus for use in a radio communication system, wherein a plurality of radio channels in a predetermined band of frequencies include a first group of channels used while awaiting a call origination or a call reception and a second group of channels used in response to the call origination or the call reception, the system including a plurality of service areas, each of the service areas being assigned a system identification number which is broadcast by one or more base stations over at least one of the radio channels, the radio communication apparatus comprising:

storing means for storing at least one stored system identification number corresponding to at least one of the service areas;

receiving means for receiving a plurality of signals, each of the signals being transmitted over at least one of the radio channels, each of the signals including a system identification number;

first selecting means for selecting one of the channels of the first group, wherein the system identification number included in the signals transmitted over the channel selected by the first selecting means coincides with the stored system identification number;

first determining means for determining an electric field intensity of signals received over at least one of the channels of the second group;

listing means for listing at least two of the channels of the second group in an order according to an electric field intensity of the signals received over the channels listed by the listing means and for giving a priority to a channel over which the signals having a strongest electric field intensity determined by the first determining means are transmitted;

second selecting means for selecting one of the channels of the second group, the channel selected by the second selecting means being coincident with the channel of the first group selected by the first selecting means;

priority giving means for giving the priority to the channel selected by the second selecting means and for removing the priority from the channel given priority by the listing means; and

synchronizing means for establishing word synchronization on signals received over the channel of the second group having the priority,

and wherein the channel over which the signals on which word synchronization is established by the synchronizing means is used for the call origination or the call reception.

8. The radio communication apparatus according to claim 7, wherein the listing means lists the channels listed by the listing means in descending order according to electric field intensity of the signals received over the channels listed by the listing means.

9. The radio communication apparatus according to claim 8, wherein the listing means gives a priority to a channel which is listed first by the listing means.

10. The radio communication apparatus according to claim 7, wherein the listing means gives a priority to the channel selected by the second selecting means by listing first the channel selected by the second selecting means.

11. A radio communication apparatus for use in a radio communication system, wherein a plurality of radio channels in a predetermined band of frequencies include a first group of channels used while awaiting a call origination or a call reception and a second group of channels used in response to the call origination or the call reception, the system including a plurality of service areas, each of the service areas being assigned a system identification number which is broadcast by one or more base stations over at least one of the radio channels, the radio communication apparatus comprising:

storing means for storing at least one stored system identification number corresponding to at least one of the service areas;

receiving means for receiving a plurality of signals, each of the signals being transmitted over at least one of the radio channels, each of the signals including a system identification number;

selecting means for selecting one of the channels of the first group, wherein the system identification number included in the signals transmitted over the channel selected by the selecting means coincides with the stored system identification number, and wherein the channel selected by the selecting means is used while awaiting the call origination or the call reception;

listing means for listing at least two of the channels of the second group over which at least one of the signals are received by the receiving means;

determining means for determining whether the channels listed by the listing means include a coinciding channel coincident with the channel selected by the selecting means, and for giving priority to the coinciding channel; and

synchronizing means for establishing word synchronization on signals received over at least the coinciding channel;

and wherein the channel over which the signals are synchronized is used for the call origination or the call reception.

12. The radio communication apparatus according to claim 11, wherein the signals received over each channel listed by the listing means have an electric field intensity greater than a predetermined electric field intensity.

13. The radio communication apparatus according to claim 11, further comprising informing means for informing a user of a service area having a system identification number which coincides with the system identification number included in the signals transmitted over the coinciding channel.

14. The radio communication apparatus according to claim 13, wherein the service area of which the user is informed is a service area not having a system identification number which coincides with the stored system identification number.

15. The radio communication apparatus according to claim 11, wherein the synchronizing means establishes word synchronization on the signals received over one of the channels listed by the listing means other than the coinciding channel when the word synchronization is not established on the coinciding channel.

16. The radio communication apparatus according to claim 11, wherein the listing means lists the channels listed by the listing means in descending order according to electric field intensity of the signals received over the channels listed by the listing means.

17. The radio communication apparatus according to claim 11, wherein the determining means gives the priority to the coinciding channel by listing the coinciding channel first.

18. A radio communication apparatus for use in a radio communication system, wherein a plurality of radio channels in a predetermined band of frequencies include a first group of channels used while awaiting a call origination or a call reception and a second group of channels used in response to the call origination or the call reception, the system including a plurality of service areas, each of the service areas being assigned a system identification number which is broadcast by one or more base stations over at least one of the radio channels, the radio communication apparatus comprising:

storing means for storing at least one stored system identification number corresponding to at least one of the service areas;

receiving means for receiving a plurality of signals, each of the signals being transmitted over at least one of the radio channels, each of the signals including a system identification number;

first listing means for listing at least two of the channels of the first group, wherein the system identification number included in the signals transmitted over each channel listed by the first listing means coincides with the stored system identification number;

selecting means for selecting one of the channels of the first group over which the signals are received by the receiving means, the channel selected by the selecting means being used while awaiting the call origination or the call reception;

second listing means for listing at least two of the channels of the second group, the channels listed by the second listing means being coincident with the channels listed by the first listing means; and

synchronizing means for establishing word synchronization on the signals received over at least one of the channels listed by the second listing means;

third listing means for listing channels of the second group other than the channels listed by the second listing means when the word synchronization is not established on at least one of the signals received over any one of the channels listed by the second listing means,

wherein the channels over which the signals are synchronized are used for the call origination or the call reception, and wherein the synchronizing means establishes word synchronization on the signals received over one of the channels listed by the third listing means.

19. The radio communication apparatus according to claim 24, wherein the signals received over the channels listed by the first listing means have an electric field intensity greater than a first predetermined electric field intensity.

20. The radio communication apparatus according to claim 19, wherein the first listing means lists the channels listed by the first listing means in descending order according to electric field intensity of the signals received over the channels listed by the first listing means.

21. The radio communication apparatus according to claim 24, wherein the signals received over each channel listed by the second listing means have an electric field intensity greater than a second predetermined electric field intensity.

22. The radio communication apparatus according to claim 21, wherein the second listing means lists the channels listed by the second listing means in descending order according to electric field intensity of the signals received over the channels listed by the second listing means.

23. The radio communication apparatus according to claim 18, wherein the signals received over each channel listed by the third listing means have an electric field intensity greater than a third predetermined electric field intensity.

24. The radio communication apparatus according to claim 23, wherein the third listing means lists the channels listed by the third listing means in descending order according to electric field intensity of the signals received over the channels listed by the third listing means.

25. The radio communication apparatus according to claim 18, further comprising informing means for informing a user of at least one of the service areas having the system identification number which coincides with the system identification number included in the signals transmitted over the channel selected by the selecting means.

26. The radio communication apparatus according to claim 18, further comprising informing means for informing a user of at least one of the service areas having the system identification number which coincides with the system identification number included in the signals synchronized by the synchronizing means.

27. The radio communication apparatus according to claim 18, further comprising informing means for informing a user of at least one of the service areas having the system identification number which coincides with the system identification number included in the signals synchronized by the synchronizing means.

28. A method of operating a radio communication apparatus for use in a radio communication system, wherein a plurality of radio channels in a predetermined band of frequencies include a first group of channels used while awaiting a call origination or a call reception and a second group of channels used in response to the call origination or the call reception, the system including a plurality of service areas, each of the service areas being assigned a system identification number which is broadcast by one or more base stations over at least one of the radio channels, the method of operating the radio communication apparatus comprising the steps of:

storing at least one stored system identification number corresponding to at least one of the service areas;

receiving a plurality of signals, each of the signals being transmitted over at least one of the radio channels, each of the signals including a system identification number;

firstly listing at least two of the channels of the first group over which at least one of the signals are received in the step of receiving;

firstly comparing the stored system identification number with the system identification numbers included in the signals received over the channels listed in the step of firstly listing;

firstly selecting one of the channels listed in the step of firstly listing when the step of firstly comparing determines a coincidence between the stored system identification number and the system identification number of the channel;

secondly listing at least two channels of the second group over which at least one of the signals are received in the step of receiving;

secondly comparing the channel selected in the step of firstly selecting with the channels listed in the step of secondly listing; and

secondly selecting one of the channels listed in the step of secondly listing coincident with the channel selected in the step of firstly selecting,

and wherein the channel selected in the step of secondly selecting is used for the call origination or the call reception.

29. A method of operating a radio communication apparatus for use in a radio communication system, wherein a plurality of radio channels in a predetermined band of frequencies include a first group of channels used while awaiting a call origination or a call reception and a second group of channels used in response to the call origination or the call reception, the system including a plurality of service areas, each of the service areas being assigned a system identification number which is broadcast by one or more base stations over at least one of the radio channels, the method of operating the radio communication apparatus comprising the steps of:

storing at least one stored system identification number corresponding to at least one of the service areas;

firstly receiving a plurality of signals, each of the signals being transmitted over at least one of the radio channels, each of the signals including a system identification number;

firstly listing at least two of the channels of the first group over which at least one of the signals are received in the step of firstly receiving;

firstly comparing the stored system identification number with the system identification numbers included in the signals received over the respective channel listed in the step of firstly listing;

secondly receiving at least one of the channels of the first group over which signals including a system identification number coincident with the system identification number stored in the step of storing are received by the step of firstly receiving;

firstly selecting one of the channels of the first group received by the step of secondly receiving when the step of firstly comparing determines a coincidence between the stored system identification number and the system identification number included in the signals received over the channel, the channel selected in the step of firstly selecting being used while awaiting the call origination or the call reception;

secondly listing at least two of the channels of the second group over which at least one of the signals including a second system identification number are received in the step of firstly receiving;

secondly comparing the channel selected in the step of firstly selecting with the channels listed in the step of secondly listing; and

secondly selecting one of the channels of the second group coincident with the channel of the first group selected in the step of firstly selecting when the step of secondly selecting determines a coincidence between the channel selected in the step of firstly selecting and one of the channels listed in the step of secondly listing,

and wherein the channel selected in the step of secondly selecting is used for the call origination or the call reception.

30. A radio communication apparatus for use in a radio communication system, wherein a plurality of radio channels in a predetermined band of frequencies includes a first group of channels used while awaiting a call origination or a call reception and a second group of channels used in response to the call origination or the call reception, the system including a plurality of service areas, each of the service areas being assigned a system identification number which is broadcast by one or more base stations over at least one of the radio channels, the radio communication apparatus comprising:

a storing device for storing at least one stored system identification number corresponding to at least one of the service areas;

a receiving device for receiving a plurality of signals, each of the signals being transmitted over at least one of the radio channels, each of the signals including a system identification number;

a first listing circuit for listing at least two of the channels of the first group over which at least one of the signals is received by the receiving device, each of the signals transmitted over channels listed by the first listing circuit including a first system identification number;

a first comparing circuit for comparing the stored system identification number with each first system identification number included in the signals received over the channels listed by the first listing circuit;

a first selecting circuit for selecting one of the channels of the first group over which at least one of the signals are received by the receiving device, the first system identification number included in the at least one signal being coincident with the stored system identification number, responsive to the first comparing circuit determining a coincidence between the stored system identification number and the first system identification number included in the at least one signal;

a second listing circuit for listing at least two of the channels of the second group over which at least one of the signals is received by the receiving device, each of the signals transmitted over the channels listed by the second listing circuit including a second system identification number;

a second comparing circuit for comparing the channel selected by the first channel selecting circuit with the channels listed by the second listing circuit;

a second selecting circuit for selecting one of the channels of the second group coincident with the channel selected by the first selecting circuit, the channel of the second group selected by the second selecting circuit being a channel over which signals are received by the receiving device, responsive to the second comparing circuit determining a coincidence between the channel selected by the first channel selecting circuit and the channel listed by the second listing circuit,

and wherein the channel selected by the second selecting circuit is used for the call origination or the call reception.