KR100976488B1 - scheduling method of uplink - Google Patents

Abstract

The present invention relates to a scheduling method of an uplink performed by a Node-B in a communication system of the wideband-code division multiple access (W-CDMA) scheme. The RNC determines the scheduling weight value for each UE based on the information managing the UE and informs the Node-B of the UE, thereby causing the Node-B to schedule the weight. The present invention is to apply scheduling to user terminals (UEs) in its service area.

Scheduling, Enhanced Uplink Dedicated Channel (E-DCH), Node-B, Radio Network Controller (RNC)

Description

Uplink Scheduling Method {scheduling method of uplink}

1 is a diagram showing a partial configuration of a communication system for explaining a scheduling method according to the present invention.

The present invention relates to a communication system, and more particularly, to an uplink scheduling method performed by a Node-B in a wideband-code division multiple access (W-CDMA) communication system.

Conventional uplink scheduling (= scheduling for uplink channel) and rate control are performed by a scheduler existing in a Radio Network Controller (hereinafter, abbreviated as RNC).

However, there is a problem that the RNC scheduler does not quickly cope with the change in the load of the uplink. That is, the RNC scheduler could not quickly control the amount of uplink load on each user equipment (hereinafter referred to as UE).

Accordingly, the 3GPP asynchronous standardization group is preparing a more efficient scheme for uplink scheduling.

SUMMARY OF THE INVENTION An object of the present invention is to devise in view of the above points, and in particular, to provide an uplink scheduling method suitable for enabling Node-B to quickly control an uplink load by controlling an uplink load amount.

A feature of the uplink scheduling method according to the present invention for achieving the above object is the step of determining a scheduling weight value for each UE based on the information that the radio network controller (RNC) manages the UE, and the wireless The network controller (RNC) informing the at least one Node-B managing the determined scheduling weight value thereof, and the Node-B applies the scheduling weight value And scheduling the UEs in its service area.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a view showing a part of the configuration of the communication system for explaining the scheduling method according to the present invention, and shows a part of the system configuration of the 3GPP asynchronous method.

Referring to FIG. 1, a system includes a plurality of UEs and a UMTS Terrestrial Radio Access Network (UTRAN).

The UTRAN includes a plurality of RNCs and a plurality of Node-Bs managed by each RNC. Here, each Node-B includes a scheduler that performs scheduling for uplink and / or uplink channels.                     

According to the dependency relationship between RNC and Node-Bs in the UTRAN, the RNC in charge of managing a particular Node-B has traffic load control for the service area of each Node-B, congestion control and a new one set within the service areas. Perform admission control for the radio link.

In addition, the RNC manages information such as path attenuation information of each UEs to Node-Bs (or path attenuation of serving UEs and neighboring cells of each UE) and uplink interference amount of serving cells and neighboring cells of each UEs. .

Especially for UEs in soft handover situation, the RNC manages path attenuation information to Node-Bs in handover of each UE. Accordingly, the RNC can more accurately know the amount of interference for neighbor cells generated by the UE, which is a handover situation.

In the present invention, the above-described information managed by the RNC is informed to Node-B. Accordingly, Node-B performs scheduling using management information provided from RNC.

In addition, the present invention is a method for efficiently performing Node-B scheduling for an enhanced uplink dedicated channel (E-DCH).

Hereinafter, an uplink scheduling procedure according to the present invention will be described.

The RNC determines a scheduling weight value for each user terminal (UE) based on the information for managing each UE. In this case, the UE management information includes a serving cell to which each UE belongs and / or a path attenuation for a neighboring cell to the serving cell, a serving cell and / or a cell neighboring the serving cell. The amount of uplink interference, and service priority of each UE. The serving cell is a service area of Node-B to which a specific UE belongs.

By way of example, the RNC assigns a small scheduling weight value to a UE located near the cell boundary, where the path attenuation for the neighboring cell is relatively small and thus may cause large interference to the neighboring cells.

The RNC then informs each Node-B of the determined scheduling weight value. Thus, each Node-B performs scheduling for each UE in its service area (= cell).

Thereafter, if necessary, the RNC notifies Node-B by updating a scheduling weight value for each UE.

Hereinafter, an example in which Node-B performs scheduling for each UE using a scheduling weight value provided from the RNC will be described.

First Embodiment

Node-B applies the scheduling weight value provided from the RNC to determine transmission priority of each UE. That is, Node-B determines the transmission priority that allows transmission to the UEs belonging to its service area.

For example, the Node-B performs scheduling in any manner to determine to allow transmission to specific UEs among UEs belonging to its service area.

Subsequently, Node-B further applies the probability determined by the scheduling weight value to the UEs that allow the transmission to finally determine whether to allow the UEs.                     

In other words, candidate UEs that are temporarily allowed to transmit by specific scheduling may not be finally allowed to transmit if they do not pass the probability check that applies the scheduling weight value.

For example, if a scheduling weight value of a UE that is allowed to transmit according to a specific scheduling scheme is 0.7, the Node-B again checks whether to allow transmission to the UE and allows the UE to have a probability of 0.7. do. At this time, the scheduling weight value is 0 or more and 1 or less.

Second Embodiment

Node-B applies the scheduling weight value provided from the RNC to determine transmission power (rate) of each UE.

For example, Node-B performs an arbitrary scheduling to temporarily allocate allowable transmission power (transmission rate) to UEs belonging to its service area. Here, UEs can transmit data at any power and / or speed within the range of allowed transmission power (rate).

At this time, Node-B sets the maximum allowable transmit power (= maximum allowable transmit power) that can be allocated to the UEs and schedules the allowable transmit power to be allocated to each UE to be finally determined within the above maximum. do.

In the present invention, Node-B performs scheduling so that the final allowable transmit power (rate) does not exceed {scheduling weight value x maximum allowable transmit power (rate)). Here, the maximum allowable transmission power (transmission rate) is a predetermined value for each UE, and the scheduling weight value is 0 or more and 1 or less.

As another example, the Node-B performs scheduling in an arbitrary manner to allocate temporary allowable transmission power (transmission rate) to specific UEs belonging to its service area.

At this time, Node-B performs scheduling so that the final allowable transmit power (rate) of each UE becomes {scheduling weight value x temporary allowable transmit power (rate)]. In this case, the scheduling weight value is a number between 0 and 1, inclusive.

As another example, the Node-B performs scheduling in an arbitrary manner to allocate temporary allowable transmission power (transmission rate) to specific UEs belonging to its service area.

At this time, Node-B does not exceed {scheduling weight value x maximum allowable transmit power (rate)} for the final allowable transmit power (rate) for each UE. The scheduling is performed so that the transmission power (transmission rate) is smaller than the temporary allowable transmission power (transmission rate).

For example, Node-B performs scheduling so that the final allowable transmit power (rate) of each UE is as shown in Equation 1 below.

P _TX = (W-1) × (P _TX '/ P _MAX ) +1

In Equation 1 above, P _TX is an allowable transmission power (transmission rate) finally determined for each UE, and P _TX 'is a temporary allowable transmission power (transmission rate) temporarily allocated by a specific scheme of scheduling for each UE. W is a scheduling weight value for each UE, and P _MAX is a maximum value (= maximum allowable transmit power) of allowable transmit power that can be allocated to predetermined UEs. At this time, the scheduling weight value is 0 or more and 1 or less.

Although the second embodiment described above has been described with respect to the transmission power, since the transmission power is directly related to the transmission rate (= transmission data rate), the second embodiment described above is equally applicable to the transmission rate.

According to the present invention described above, since the information managed by the RNC can be reflected in Node-B scheduling by the scheduling weight value provided by the RNC, the uplink load can be controlled quickly. Thus, it can cope with the uplink load change quickly.

In addition, by scheduling the uplink Node-B according to the present invention, it is possible to more efficiently control the uplink noise rise.

In addition, Node-B scheduling according to the present invention is more efficient in controlling the load of the uplink quickly by adjusting the transmission power and / or transmission rate of each UE, thereby making the load change of the uplink smaller. It also allows for relatively small noise rise margin of the uplink.

Furthermore, the capability of Node-B scheduling according to the present invention (quick response to load change in uplink) leads to gains in cell throughput and cell coverage expansion.

In addition, the present invention can be more efficiently applied to scheduling of an enhanced uplink dedicated channel (E-DCH), which is to be applied to a 3GPP wireless mobile communication system in accordance with a demand for higher speed of uplink.

Claims (7)

Determining, by the radio network controller (RNC), a scheduling weight value for each user terminal (UE) based on information for managing the user terminal (UE); Notifying, by the radio network controller, at least one Node-B managing the determined scheduling weight value thereof; And scheduling, by the Node-B, the user terminal (UEs) of its service area by applying the scheduling weight value. The method of claim 1, wherein the information managing the user terminal (UE) is: Path attenuation for at least one of a serving cell to which each user terminal UE belongs and neighbor cells adjacent to the serving cell, an upward direction of at least one of the serving cell and cells neighboring to the serving cell The amount of link interference, and the service priority of each user terminal (UE), the scheduling method of the uplink. The method of claim 1, wherein the scheduling, Uplink scheduling method according to claim 1, wherein the Node-B determines a transmission priority for allowing transmission to UEs belonging to its service area. The method of claim 3, wherein the scheduling, Allowing the Node-B to perform scheduling in any manner to temporarily allow transmission to specific UEs among UEs belonging to its service area; The Node-B further applies the probability determined by the scheduling weight value to the UEs whose transmission permission has been determined to finally determine whether to allow transmission for the UEs whose transmission permission has been determined. Uplink scheduling method comprising the. The method of claim 1, wherein the scheduling, Uplink scheduling method according to claim 1, wherein the Node-B determines at least one of transmission power and transmission rate of UEs belonging to its service area. The method of claim 1, wherein the scheduling, Uplink scheduling method according to claim 1, wherein the Node-B allocates an uplink channel to UEs belonging to its service area. 7. The method of claim 6, wherein the uplink channel is an enhanced uplink dedicated channel (E-DCH).

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