GB2371183A

GB2371183A - Managing a cell resource in a mobile communication system to carry out radio resource management between base and control stations

Info

Publication number: GB2371183A
Application number: GB0126034A
Authority: GB
Inventors: Sang-Ho Kim
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2000-11-02
Filing date: 2001-10-30
Publication date: 2002-07-17
Anticipated expiration: 2021-10-30
Also published as: CN1177495C; GB0126034D0; KR20020034067A; CN1352508A; GB2371183B

Abstract

A mobile communication system and a method for managing a cell resource in a mobile communication system is disclosed. A resource status report message including UARFCN (UTRA Absolute Radio Frequency Channel Number where UTRA means UMTS Terrestrial Radio Access) and sector relating information is reported from a base station to a control station by the unit of CDMA absolute frequency, whereby the control station enables to manage a resource of the base station by the frequency unit. The report is received by the unit of local cells having a same frequency from the base station and the control station generates cells as many as a count of implemented sectors in accordance with the resource status report message.

Description

METHOD FOR MANAGING CELL RESOURCE IN MOBILE

COMMUNICATION SYSTEM BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a mobile communication system, and more particularly, to a method for managing a cell resource in mobile communication system.

Background of the Related Art Generally, a UMTS structure is constructed with a user equipment (hereinafter abbreviated UE) 30, UTRAN 20, and a core network (hereinafter abbreviated CN) 10, which is shown in FIG. 1.

FIG. 2 illustrates a block diagram of a connection between CN 10 and UTRAN 20 and a basic structure of UTRAN 20 in a basic structure of UMTS.

Referring to FIG. 2, UTRAN 20 includes radio network subsystems (hereinafter abbreviated RNS) 21 and 22 connected to CN 10 through logical interfaces each of which is called Iu.

Each of RNSs 21/22 includes a radio network controller (hereinafter abbreviated RNC) 21a/22a and at least one of logical nodes 21b, 21c, 22b, and 22c.

The respective logical nodes (hereinafter abbreviated Node B) 21b, 21c, 22b, and 22c take charge of radio transmission with various UEs 30 located in their service areas, and Node B is

connected to RNC 21a or 22a in its RNS 21 or 22 through an interface which is called Iub.

The RNC 21a or 22a is responsible for using a radio resource and controlling an integrity, takes charge of handover requiring a signal processing for various UEs, and includes assembly/disassembly functional blocks for supporting massive diversity between different Node B 21b, 21c, 22b, and 22c.

RNC 21a and 22a of the different RNS 21 and 22 in UTRAN 20 are connected to each other through a logical interface called Iur, and each RNS takes charge in managing its cell resource.

When local cells, which are equipments mounted on Node B 21b, 21c, 22b, and 22c, are valid for RNC 21a and 22a to construct cells, the RNC 21a and 22a establishes cells, common physical channels, and common transport channels in the local cells taken charge of by Node B 21b, 21c, 22b, and 22c.

FIG. 3 illustrates a diagram of a status transition of a local cell of a base station on an Iub interface between control base stations in UTRAN.

FIG. 4 illustrates a procedure that a base station transmits a resource status report message to a control station.

Referring to FIG. 3 and FIG. 4, when a local cell is generated from Node B, the Node B transmits a message that the local cell is available to RNC through the resource status report message of the base station in FIG. 4.

When it is impossible-to use the local cell at Node B, the base station sends a message that the local cell is deleted to RNC so that RNC releases various resources allocated to the local cell.

FIG. 5 illustrates contents of a resource status report message according to a related art.

Referring to FIG. 5, information regarding Node B should contain information elements of DL or Global Capacity Credit, Common Channels Capacity Consumption Law, and Dedicated Channels Consumption Law, and may include UL Capacity Credit selectively.

Information regarding a local cell should include Local cell ID, Add/Delete Indicator, and Maximum DL Power Capability. When a local cell is added, the information should include DL or Global Capacity Credit, Common Channels Capacity Consumption Law, and Dedicated Channels Consumption Law, and may include UL Capacity Credit selectively.

Local cell ID is an identifier information of the local cell about a report unit of the base station transporting the resource status report message.

The RNC, based on information in connection with the Node B and local cell, establishes a cell, a common physical channel CPCH, and a common transport channel CTCH at the corresponding Node B.

In the related art, such a resource status report message is reported to RNC by a unit of local cell or Node B, whereby the following problems are brought about.

First of all, because DL and UL Capacity Credit included in the resource status report message reported from Node B is allocated from the respective sectors of the same UARFCN of the corresponding base station, RNC fails to notice the information change of such DL and UL Capacity Credit. Hence, it is difficult to manage a cell resource.

Besides, the number of sectors and UARFCN used by the local cell is a local cell add information of Node B regardless of RNC, which should be reported on NBAP protocol in RNC. Yet, the standard according to the related art fails to include this information element. Thus, RNC fails to provide information about the number of sectors and UARFCN possibly processed by a random base station. Hence, a vendor should gain access to Node B and RNC.

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to a method for managing a cell resource in mobile communication system that addresses one or more problems due to limitations and disadvantages of the related art.

It would be desirable to provide a method for managing a cell resource in mobile communication system which allows RNC manages a resource of Node B by a frequency unit.

It would also be desirable to provide a method for managing a cell resource in mobile communication system which enables RNC to avoid managing a resource of Node B doubly.

Additional advantages, objects, and features---. of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Accordingly, the invention provides, in a radio resource management between a base station and a control station, a method of managing a cell resource in a mobile communication system, such as a UMTS system, including the steps of receiving a resource status report message by the unit of local cells having a same frequency from the base station, having the control station generate cells as many as a count of implemented sectors in accordance with the resource status report message, and having the control station carry out the radio resource management of the base station by the unit of the generated cells.

Preferably, the resource status report message includes an identifier of the unit of the local cells having the same frequency in the base station, information about the same frequency, a count of sectors available for the base station, and information about the count of the sectors implemented to the base station.

Preferably, an identifier of a local cell corresponding to the generated cell is generated by combining the identifier of the unit of the local cells with an identifier of the implemented sector.

Preferably, the method further includes the step of setting up common channels and exclusive channels as many as the count of the implemented sectors between the base and control stations.

Preferably, the resource status report message includes radio resource capacity that the base station enables to provide on uplink or down link.

Preferably, the control station manages the radio resource capacity to use commonly or exclusively by the unit of the same frequency in accordance with the resource status report message.

In another aspect of the present invention, in a radio resource management between a base station and a control station, a method of managing a cell resource in a mobile communication system, such as a UMTS system, includes the steps of transmitting a resource status report message including information about

allocated frequency and sector of the base station to the control station and receiving allocation of a resource from a cell mapped to a local cell generated as many as the count of the sectors by the unit of the allocated frequency.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment (s) of the invention and together with the description serve to explain the principle of the invention. In the drawings: FIG. 1 illustrates a structure of UMTS; FIG. 2 illustrates a structure of UTRAN in UMTS; FIG. 3 illustrates a diagram of a status transition of a

local cell of a base station on an Iub interface between control base stations in UTRAN ; FIG. 4 illustrates a procedure that a base station transmits a resource status report message to a control station; FIG. 5 illustrates contents of a resource status report message according to a related art;

FIG. 6 illustrates contents of a resource status report message according to an embodiment of the present invention ; and FIG. 7 illustrates a flowchart of generating a base station cell from a control station according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

The preferred embodiment is characterized in that a resource status report message including UARFCN and sector-relating information is reported from a base station to a control station by the unit of CDMA absolute frequency, whereby the control station enables to manage a resource of the base station by the frequency unit.

Moreover, the preferred embodiment is characterized in that more local cells of a base station are installed through NBAP protocol without Implementation O & M message relating to UARFCN and sector of the local cell to be added to the base station.

FIG. 6 illustrates contents of a resource status report message according to the preferred embodiment.

Referring to FIG. 6, information in connection with Node B should include DL (downlink) or Global Capacity Credit, Common

Channels Capacity Consumption Law, and Dedicated Channels Consumption Law. And, the information relating to Node B may further include UL (uplink) Capacity Credit selectively.

The DL or Global Capacity Credit is the information which may be provided by a base station transporting the resource status report message on downlink or the information of total radio resource capacity.

The Common Channels Capacity Consumption Law and Dedicated Channels Consumption Law are the information of radio resource consumption used by the base station transmitting the resource status report message for setting up common channels and dedicated channels.

The UL Capacity Credit is the information of radio resource capacity on uplink, which the base station transmitting the resource status report message enables to provide.

Information in connection with local cell group should include Local Cell Group ID, Add/Delete Indicator, UARACN, Sector User, Implemented Sector, and Maximum DL Power Capability. When a local cell is added, the information should include DL or Global Capacity Credit, Common Channels Capacity Consumption Law, and Dedicated Channels Capacity Consumption Law and may further include UL Capacity Credit selectively.

The Local Cell Group ID is the identifier information about a report unit by which the Node B transmits the resource status

report message. Namely, because the number of local cells is determined by {FA number x Sector number} where FA is frequency assignment, some of the local cells having the same UARFCN are segregated into one group. Thus, the Local Cell Group ID indicates the identifier information of the segregated group.

The Add/Delete Indicator is the information indicating whether the local cell group is added to or deleted from the corresponding base station by the base station transmitting the resource status report message.

The Maximum DL Power Capability is the information of transmission power available most when the base station transmitting the resource status report message downlinks.

The UARACN is the information about an absolute frequency allocated to the local cell group in the base station transmitting the resource status report message. The Sector Use is the information about the number of sectors available for the base station. And, the Implemented Sector is the information about the number of the implemented sectors.

Namely, in the preferred embodiment, the base station provides the control station with the information of the UARFCN able to be allocated by the base station and the UL and DL Capacity Credits available per each UARFCN by adding UARFCN, the number of available sectors, and the number of implemented sectors to the information element called the local cell group.

RNC having provided with such information generates cells in accordance with the following procedure in FIG. 7.

FIG. 7 illustrates a flowchart of generating a base station cell from a control station according to the preferred embodiment.

Referring to FIG. 7, RNC receives a resource status report message including the contents in FIG. 6 in connection with a local cell group (local cells having the same UFRACN) from Node B (S20).

The RNC enables to recognize UARFCN information and the number of available sectors (Sector Use) and presently implemented sectors (Implemented Sector) from the resource status report message, and manages the amount (UL/DL Capacity Credit) of a radio resource to use commonly and exclusively by the UARFCN unit.

For such a purpose, first of all, the RNC generates cells amounting to the number of the implemented sectors. In this case, a local cell ID of the generated cell is attained by adding the ID of the local cell group to a sector ID (S21). Namely, the ID of the local cell group and ID of the implemented sector are added so as to generate the local cell ID. Thus, the RNC organizes the cell.

The RNC carries out the procedure of generating cell, common channel, and exclusive channel with Node B as many as the number of sectors implemented by the unit of the local cell ID (S22, S23).

If the cells fail to organize the local cell group completely, the RNC makes the local cell ID again (S21).

Accordingly, the embodiments of the invention use Node B in a manner that sectors are divided by the UARFCN unit and allocates dynamically a radio resource between sectors by the UARFCN unit, thereby enabling to reduce an overlapping possibility, which is lower than is managed by the cell unit in the related art, of a resource and facilitate the resource management.

Moreover, the present invention enables to establish more local cells of a base station without Implementation O & M message between RNC and Node B.

Furthermore, the present invention is applicable to a field of adding cells between RNC and Node B in IMT-2000 system of DS method.

The forgoing embodiments are merely exemplary and are not to be construed as limiting the present invention. The present teachings can be readily applied to other types of apparatuses. The description of the preferred embodiment is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art.

Claims

CLAIMS :

1. A method of managing a cell resource in a mobile communication system, to carry out radio resource management between a base station and a control station, comprising the steps of: receiving a resource status report message by the unit of local cells having a same frequency from the base station; having the control station generate cells as many as a count of implemented sectors in accordance with the resource status report message ; and having the control station carry out the radio resource management of the base station by the unit of the generated cells.

2. The method of claim 1, wherein the resource status report message includes an identifier of the unit of the local cells having the same frequency in the base station, information about the same frequency, a count of sectors available for the base station, and information about the count of the sectors implemented to the base station.

3. The method of claim 2, wherein an identifier of a local cell corresponding to the generated cell is generated by

combining the identifier of the unit of the local cells with an identifier of the implemented sector.

4. The method of claim 1, further comprising the step of setting up common channels and exclusive channels as many as the count of the implemented sectors between the base and control stations.

5. The method of claim 1, wherein the resource status report message includes radio resource capacity that the base station enables to provide on uplink or down link.

6. The method of claim 5, wherein the control station manages the radio resource capacity to use commonly or exclusively by the unit of the same frequency in accordance with the resource status report message.

7. A method of managing a cell resource in a mobile communication system, to carry out radio resource management between a base station and a control station, comprising the steps of: transmitting a resource status report message including information about allocated frequency and sector of the base station to the control station ; and

receiving allocation of a resource from a cell mapped to a local cell generated as many as the count of the sectors by the unit of the allocated frequency.

8. The method of claim 7, wherein the resource status report message includes an identifier of the unit of the local cells having the same frequency in the base station, information about the same frequency, a count of sectors available for the base station, and information about the count of the sectors implemented to the base station.

9. The method of claim 8, wherein an identifier of a local cell corresponding to the generated cell is generated by combining the identifier of the unit of the local cells with an identifier of the implemented sector.

10. The method of claim 7, further comprising the step of setting up common channels and exclusive channels as many as the count of the implemented sectors between the base and control stations.

11. The method of claim 7, wherein the resource status report message includes radio resource capacity that the base station enables to provide on uplink or down link.

12. The method of claim 7, wherein the control station allocates the radio resource capacity to use commonly or exclusively by the unit of the same frequency in accordance with the resource status report message.

13. Apparatus adapted to carry out the steps of the method of any of claims 1 to 12.

14. A mobile communication system adapted to carry out the steps of the method of any of claims 1 to 12.

15. A method of managing a cell resource in a mobile communication system substantially as herein described with reference to figures 6 and 7 of the accompanying drawings.