KR20020058613A - Method for Reporting Information for Variable Bit Rate in W-CDMA - Google Patents

Abstract

PURPOSE: A method for reporting information for a diversified bit rate in an IMT-2000 system is provided to make an MAC(Medium Access Control) periodically and repeatedly report the data amount of an RLC(Radio Link Control) buffer to an RRC layer so that the RRC(Radio Resource Control) layer can efficiently manage resources, in case that the operation of the RRC layer is not executed properly when the data amount of the RLC buffer varies at more than or less than a threshold. CONSTITUTION: In an event-triggered periodic mode, in case that an upper threshold is more than the data amount of an RLC buffer and the level is maintained during an upper guard timer, an MAC layer reports the data amount of the RLC buffer to an RRC layer. If a measure suited to the report is not executed by the RRC layer, the MAC layer periodically reports the fact to the RRC layer according to an event-triggered periodic report interval. If an operation for the MAC layer's report is generated from the RRC layer or the data amount of the RLC buffer gets smaller than the threshold, the MAC layers stops the report.

Description

Method for Reporting Information for Variable Bit Rate in W-CDMA

The present invention relates to a next-generation mobile communication system, and in particular, when the amount of data to be transmitted varies according to the characteristics of a variable bit rate service, a radio resource control layer (hereinafter referred to as RRC) layer configures or transmits a physical channel. The present invention relates to a method for reporting information for a variable bit rate in a next generation mobile communication system for reporting an RLC buffer between a medium access control layer (hereinafter referred to as MAC) layer and an RRC layer, which is suitable for performing channel configuration.

As is known, the conventional W-CDMA mobile communication system uses a common medium access control (CMAC) measurement request and a CMAC-measurement indication primitive between the RRC layer and the MAC layer to support a multi-bit bit rate service. The CMAC-measurement request of the Radio Link Control (hereinafter referred to as RLC) buffer defines the RLC buffer report mode and the RLC buffer threshold. The CMAC measurement indication primitive reports the amount of RLC buffer data from the MAC layer to the RRC layer according to the above rule.

For reference, the RLC layer is a layer that is located in the RRC layer and the MAC layer to divide the data size suitable for the air interface, perform a reverse process, and perform functions such as data suitability verification and retransmission. Have. In addition, the RRC layer is a layer for controlling a radio resource stack and a radio interface stack of a control station (hereinafter referred to as RLC), and serves to control the aforementioned RLC layer and CMAC layer. The MAC layer is a layer that manages a transport channel and is classified into a CMAC and a DMAC. The CMAC is generated on a cell basis and serves as a path for generating a dedicated wireless channel. On the other hand, since the DMAC is connected to the network side (UTRAN) through a dedicated wireless channel with a specific terminal, as many as the number of terminals must be generated, but there is a limit to the resource limit.

Accordingly, in the conventional WCDMA system, a measurement request, an indication method, and an information element between the RRC layer and the MAC layer for supporting multi-variable bit rates are as follows.

First, if the radio bearer is a variable bit rate service, the RRC layer sends a CMAC-measurement request primitive message to the MAC layer. In this case, the information included in the message includes a measurement mode for selecting a periodic mode or an event-triggered mode, or both modes, and an event-triggered mode. In this case, the RLC buffer threshold information is included, and in the case of the periodic mode, the information on the report interval is included.

The MAC layer operates as follows according to the mode. In the periodic mode, the MAC layer reports the amount of the RLC buffer to the RRC layer when the interval is reached according to the report interval. However, in the event-triggered mode, the amount of the RLC buffer is higher than the Upper threshold according to the RLC buffer threshold set in the request of the RLC buffer for the MAC layer of the RRC layer. Report the amount of the RLC buffer below the Lower threshold.

According to the periodic mode or the event-triggered mode, the RRC layer that receives a report on the RLC buffer from the MAC layer increases the amount of data transmitted in the downlink according to the amount of the RLC buffer. Physical channel reconfiguration or transmission channel reconfiguration.

For example, as shown in FIG. 1, in the trigger generation mode, physical channel reconfiguration occurs frequently when a ping-pong around the threshold is reported when the MAC layer reports the RRC layer. That is, the RRC layer uses a lower spreading factor due to the report of the first trigger occurrence (reconfiguration of the physical channel). This sends a CMAC-measurement request for the new channel to the MAC layer. After that, there will be a Lower Threshold at a level similar to the current Upper Threshold, and the amount of RLC buffer will drop below the Lower Threshold and report again. As a result, an unnecessary operation is performed, and if the operation for the last report cannot be performed in the RRC layer due to insufficient capacity, no report exists afterwards.

However, in the prior art, the following problems occur in the operation of the RRC using the measurement information.

First, reconstruction may occur frequently due to a phenomenon in which the amount of data frequently pings around a threshold. This ping-pong phenomenon occurs when a bottleneck occurs throughout the network. It also occurs when the frame error rate temporarily increases due to the propagation environment in the common air interface section.

Second, in the event triggered mode (Event-triggered Mode), when reported by the trigger occurs, if the RRC temporarily failed to meet the conditions due to resource shortage (channelization code) or base station capacity, etc. Occasionally, the appropriate performance of a report may be deleted.

Accordingly, an object of the present invention has been made in view of the above-mentioned problems of the prior art, and in the method in which the MAC layer reports the data amount of the RLC buffer to the RRC layer, the data amount of the RLC buffer is greater than or equal to a threshold value. In the case of the following fluctuation, the next-generation mobile communication system for allowing the RRC layer to efficiently manage resources by waiting for a predetermined period and periodically reporting again when proper operation of the RRC layer according to this report is not performed. To provide an information reporting method for a variable bit rate in.

According to the method feature of the present invention for achieving the above object, the radio resource control layer (RRC) for controlling resources for the variable bit rate is a medium access control layer (MAC) with information on the method of reporting the resource information Requesting reporting of the resource information, and periodically reporting the resource information periodically according to the method of reporting the resource information, or periodically after the case where the resource changes above or below a threshold. And reporting the information to the radio resource control layer.

Preferably, the medium access control layer reports on the resource information to the radio resource control layer when the resource is maintained for a predetermined time above or below a threshold, and the operation of the radio resource control layer corresponding to the report is performed. In case it is not performed, the resource information is periodically reported.

1 shows a graph over time according to a prior art RLC buffer reporting method.

Figure 2 shows a graph over time according to the RLC buffer reporting method according to the present invention.

Hereinafter, a configuration and an operation according to an exemplary embodiment of the present invention will be described with reference to the accompanying drawings.

The present invention complements the measurement information reporting between the RRC layer and the MAC layer, so that the system can be stably adapted to multivariate bit rate services.

Information supplemented in the present invention is as follows.

A guard timer is included in the CMAC-measurement request for the MAC layer of the RRC layer. That is, the conventional upper and lower thresholds are applied together with the guard timer.

Therefore, if the amount of data transmitted in downlink is increased, even if the amount of RLC buffer is higher than the upper threshold (Upper threshold), if the level is maintained until the corresponding Guard Timer expires MAC Report the RLC buffer from layer to RRC layer. Even if the amount of data transmitted in the downlink decreases, even if it is lower than the lower threshold of the RLC buffer, the level is maintained until the corresponding Guard Timer expires. Report an RLC buffer.

In addition, the present invention further includes an event-triggered periodic mode in a mode included in a CMAC measurement request for the MAC layer of the RRC layer. In the conventional case, since only the periodic mode and the event-triggered mode exist, when the event-triggered mode is used, the RRC layer temporarily fails to perform appropriate reporting. There was no way to report back. Therefore, the service user may experience a low call quality service when such a case occurs. In this case, in order to support the event-triggered periodic mode, the present invention provides an event-triggered periodic report interval for the event-triggered periodic mode. To perform.

The measurement procedure for supporting the variable bit rate in the W-CDMA system according to the present invention is as follows.

If the radio bearer is a variable bit rate service, the RRC layer sends a CMAC-measurement request primitive to the MAC layer. Information at this time is as follows.

Measurement modes include Periodic Mode, Event-triggered Mode, Event-triggered Periodic Mode (Periodic Mode), upper RLC buffer thresholds, and trigger generation. Mode, upper guard timer included for event-triggered mode, event-triggered periodic mode, lower RLC buffer threshold, and upper bound timer Like the Guard Timer), in case of the Event-triggered Mode, the Lower Guard Timer included in the Event-triggered Periodic Mode, and the Periodic Mode, The included report interval and the event-triggered periodic report interval included in the event-triggered periodic mode are included.

The MAC layer operates as follows, as shown in FIG. 2, depending on the mode.

2 is a diagram showing a graph over time according to the RLC buffer reporting method according to the present invention.

Referring to FIG. 2, in the event-triggered periodic mode, the upper threshold is set according to an RLC buffer threshold and a guard timer set in a CMAC measurement request message requested from the RRC layer to the MAC layer. If the value (Upper Threshold) is higher than this and the level is maintained for the Upper Guard Timer, the amount of the RLC buffer is reported to the RRC layer. If the appropriate action for this report is not performed at the RRC layer, it is reported periodically to the RRC layer according to the Event-triggered Periodic Report Interval. Therefore, when an operation for reporting of the MAC layer occurs in the RRC layer, or when the amount of the RLC buffer falls below the threshold, the MAC layer stops reporting.

When the amount of the RLC buffer is lower than the lower threshold and the level is maintained for the lower guard timer, the amount of the RLC buffer is reported to the RRC layer. If the appropriate action for this report is not performed at the RRC layer, it is reported periodically to the RRC layer according to the Event-triggered Periodic Report Interval. Therefore, when an operation for reporting of the MAC layer occurs in the RRC layer or when the amount of the RLC buffer rises above the threshold, the MAC layer stops reporting.

In the event-triggered mode, the RLC buffer threshold set in the CMAC measurement request message from the RRC layer to the MAC layer, and the amount of the RLC buffer depends on the guard timer. If it is above and the level is maintained for the upper guard timer, the amount of the RLC buffer is reported to the RRC layer.

In the periodic mode, as in the prior art, the MAC layer reports the amount of the RLC buffer to the RRC layer when the corresponding interval is reached according to the report interval.

As described above, the RRC layer provided with information on the RLC buffer from the MAC layer is divided into a case of downlink data that is increased according to the amount of RLC buffer reported by the MAC and a case of downlink data that is decreased, and thus the physical channel reconfiguration or transport channel. Perform reconstruction Here, the physical channel reconfiguration applied to the multi-variable bit rate service corresponds to a case of changing the spreading factor. In addition, the transport channel reconfiguration corresponds to a case in which a transport format set (TFS) or a transport format combination set (TFCS) needs to be changed.

As described above, the present invention relates to a threshold value that may occur when only an upper threshold and a lower threshold exist in a data measurement reporting procedure of an RLC buffer between a MAC layer and an RRC layer. The Ping-Pong phenomenon in can be prevented by setting an Upper Guard Timer and a Lower Guard Timer.

In addition, if an appropriate action is not performed at the RRC layer using the event-triggered periodic mode, the measurement report mode is periodically performed at every event-triggered periodic report interval. As a result, an appropriate operation for resource management of the RRC layer is induced to enable efficient resource control.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the examples, but should be defined by the claims.

Claims (3)

Requesting reporting of the resource information to the media access control layer (MAC) by the radio resource control layer (RRC) controlling the resource for the variable bit rate together with information on how to report the resource information; Reporting the resource information to the radio resource control layer periodically on a case-by-case basis depending on the method of reporting the resource information periodically or after the case where the resource changes above or below a threshold. An information reporting method for a variable bit rate in a next generation mobile communication system, comprising: a. 2. The method of claim 1, wherein the medium access control layer reports resource information to a radio resource control layer when the resource is maintained for a predetermined time above or below a threshold. Information reporting method for bit rate. 2. The method of claim 1, wherein the medium access control layer periodically reports the resource when the resource fluctuates above or below a threshold, and when the operation of the radio resource control layer corresponding to the report is not performed. An information reporting method for a variable bit rate in a next generation mobile communication system, characterized by reporting on information.