Radio network controller and channel assignment method by the same

Abstract

To provide a technique of making it possible to shorten a time taken by channel switching. Further, to provide a technique of enabling simplification of a channel switching procedure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing an outline of a W-CDMA system.

FIG. 2 is a conceptual diagram of individual channels and common channels.

FIG. 3 is a diagram showing an operation flow of channel switching.

FIG. 4 is a diagram showing an individual channel setting sequence at the time of apparatus resumption of a radio network controller or a base station.

FIG. 5A is a diagram showing an example of an individual channel management table in the radio network controller.

FIG. 5B is a diagram showing an example of the individual channel management table in the radio network controller.

FIG. 6A is a diagram showing a correspondence between a user equipment and an individual channel.

FIG. 6B is a diagram showing a correspondence between the user equipment and an individual channel.

FIG. 7 is a diagram showing an operation flow of channel switching.

FIG. 8 is a diagram showing a channel switching sequence in the case where an individual channel is held.

FIG. 9 is a diagram showing a processing sequence example at the time of channel switching.

FIG. 10 is a diagram showing a sequence for releasing a held individual channel.

FIG. 11 is a diagram showing a sequence for releasing an individual channel.

Claims

1. A radio network controller for assigning, to each wireless terminal connected to a wireless network, one of an individual channel exclusively used by the wireless terminal and a common channel shared with at least one wireless terminal different from the wireless terminal as a communication channel, the radio network controller comprising:a determination portion for determining that an individual channel is to be assigned to a wireless terminal; andan assignment portion for, when the assignment of the individual channel has been determined, assigning an individual channel resource secured and held before the determination to the wireless terminal.

2. A radio network controller according to claim 1, wherein when the determination portion has determined that a communication channel used by a wireless terminal is to be switched from a common channel to an individual channel, the assignment portion assigns an individual channel resource secured and held before the determination of the switching to the wireless terminal.

3. A radio network controller according to claim 1, further comprising: a storage portion for storing identification information of each individual channel resource secured and held before the determination by the determination portion and a use state thereof,wherein the assignment portion finds an unused individual channel resource from the storage portion and assigns the found individual channel resource to a wireless terminal.

4. A radio network controller according to claim 1, further comprising: a securement portion for securing an individual channel resource for assigning an individual channel to a wireless terminal even when there exists no wireless terminal to which the individual channel should be assigned.

5. A radio network controller according to claim 4, wherein the securement portion secures the individual channel resource at the time of activation of the radio network controller.

6. A radio network controller according to claim 4, wherein when switching from an individual channel to a common channel has been carried out for a certain wireless terminal, the securement portion secures an individual channel resource used by the certain wireless terminal without releasing the individual channel resource.

7. A radio network controller according to claim 6, further comprising: a storage portion for storing the certain wireless terminal and the individual channel resource used by the certain wireless terminal in association with each other,wherein when the determination portion determines that a communication channel used by the certain wireless terminal is to be switched from a common channel to an individual channel again, the assignment portion refers to the storage portion and assigns the individual channel resource originally used by the certain wireless terminal.

8. A radio network controller according to claim 7, wherein the individual channel resource used by the certain wireless terminal is released when the certain wireless terminal moves to a wireless area that is different from a wireless area in which the certain wireless terminal is capable of using the individual channel resource.

9. A radio network controller according to claim 1, wherein at a time of outgoing from a wireless terminal or incoming to the wireless terminal, when the determination portion determines that an individual channel is to be assigned to the wireless terminal that is an outgoing terminal or an incoming terminal, the assignment portion assigns an individual channel resource secured and held before the determination to the wireless terminal.

10. A channel assignment method by a radio network controller for assigning, to each wireless terminal connected to a wireless network, one of an individual channel exclusively used by the wireless terminal and a common channel shared with at least one wireless terminal different from the wireless terminal as a communication channel, the channel assignment method by the radio network controller comprising the steps of:determining that an individual channel is to be assigned to a wireless terminal; andassigning, when the assignment of the individual channel is determined, an individual channel resource secured and held before the determination to the wireless terminal.

11. A channel assignment method by a radio network controller according to claim 10, further comprising the steps of: assigning, when it is determined that a communication channel used by a wireless terminal is to be switched from a common channel to an individual channel, an individual channel resource secured and held before the determination of the switching to the wireless terminal.

12. A channel assignment method by a radio network controller according to claim 10, further comprising the steps of: storing identification information of each individual channel resource secured and held before it is determined that a communication channel used by a wireless terminal is to be switched from a common channel to an individual channel and a use state thereof; andfinding an unused individual channel resource with reference to the identification information of the secured and held individual channel resource and the use state thereof and assigning the found individual channel resource to the wireless terminal.

13. A channel assignment method by a radio network controller according to claim 10, further comprising the steps of: securing an individual channel resource for assigning an individual channel to a wireless terminal even when wireless terminal to which the individual channel should be assigned dose not exist.

14. A channel assignment method by a radio network controller according to claim 13, further comprising the steps of: securing the individual channel resource at a time of activation of the radio network controller.

15. A channel assignment method by a radio network controller according to claim 13, further comprising the steps of: securing, when switching from an individual channel to a common channel is carried out for a certain wireless terminal, an individual channel resource used by the certain wireless terminal without releasing the individual channel resource.

16. A channel assignment method by a radio network controller according to claim 15, further comprising the steps of: storing the certain wireless terminal and the individual channel resource used by the certain wireless terminal in association with each other, andreferring, when it is determined that a communication channel used by the certain wireless terminal is to be switched from a common channel to an individual channel again, to associations among identification information of each secured and held individual channel resource, a use state thereof, and the individual channel resource used by the certain wireless terminal and assigning the individual channel resource originally used by the certain wireless terminal.

17. A channel assignment method by a radio network controller according to claim 16, further comprising the steps of: releasing the individual channel resource used by the certain wireless terminal when the certain wireless terminal moves to a wireless area that is different from a wireless area in which the certain wireless terminal is capable of using the individual channel resource.

18. A channel assignment method by a radio network controller according to claim 10, further comprising: assigning, at a time of outgoing from a wireless terminal or incoming to the wireless terminal, when it has been determined that an individual channel is to be assigned to the wireless terminal that is an outgoing terminal or an incoming terminal, an individual channel resource secured and held before the determination to the wireless terminal.