KR101719072B1 - Method for transmitting scheduling request effectively in wireless communication system - Google Patents

Abstract

The present invention relates to a wireless communication system and a wireless terminal for providing wireless communication, and more particularly, to a wireless communication system and a wireless terminal for providing wireless communication, A random access channel (Random Access Channel) process is performed, radio resources are appropriately selected when radio resources are allocated through their radio terminal identifiers, thereby improving radio resource waste and efficiency.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method for efficiently transmitting a scheduling request in a mobile communication system,

The present invention relates to a method of exchanging data between a base station and a mobile station in an LTE system (Long Term Evolution System). More particularly, in the course of performing an RACH process, The present invention relates to a method for increasing the efficiency and waste of radio resources by appropriately selecting radio resources when radio resources are allocated through identifiers.

1 is a diagram illustrating a network structure of an Evolved Universal Mobile Telecommunications System (E-UMTS), which is a conventional mobile communication system to which the present invention is applied. The E-UMTS system evolved from the existing UMTS system and is currently undergoing basic standardization work in 3GPP. The E-UMTS system may be referred to as an LTE (Long Term Evolution) system.

The E-UMTS network can be divided into E-UTRAN and CN. The E-UTRAN includes a User Equipment (hereinafter abbreviated as UE), a base station (abbreviated as eNode B hereinafter), a Serving Gateway (abbreviated as S-GW hereinafter) And a Mobility Management Entity (hereinafter abbreviated as MME) for managing the mobility of the mobile terminal. One eNode B may have more than one cell.

2 and 3 illustrate a structure of a radio interface protocol between a terminal and a base station based on the 3GPP radio access network standard. The wireless interface protocol horizontally comprises a physical layer, a data link layer, and a network layer, and vertically includes a user plane for data information transmission and a control plane And a control plane for signal transmission. The protocol layers are classified into L1 (first layer), L2 (second layer) and L3 (third layer) based on the lower three layers of the Open System Interconnection (OSI) .

Hereinafter, each layer of the wireless protocol control plane of FIG. 2 and the wireless protocol user plane of FIG. 3 will be described.

The physical layer as the first layer provides an information transfer service to an upper layer using a physical channel. The physical layer is connected to a medium access control layer (upper layer) through a transport channel, and data between the medium access control layer and the physical layer moves through the transport channel. Data is transferred between the different physical layers, that is, between the transmitting side and the receiving side physical layer through the physical channel.

The Medium Access Control (MAC) of the second layer provides a service to a radio link control layer that is an upper layer through a logical channel. The second layer of Radio Link Control (RLC) layer supports the transmission of reliable data. The PDCP layer of the second layer is a header compression that reduces the IP packet header size, which is relatively large and contains unnecessary control information, in order to efficiently transmit the IP packet, such as IPv4 or IPv6, Compression function. The PDCP layer is also used to perform encryption of C-plane data, for example, an RRC message. PDCP also encrypts U-plane data.

The radio resource control (RRC) layer located at the bottom of the third layer is defined only in the control plane and is configured to perform a configuration of a radio bearer (RB) -configuration and release of the logical channel, the transport channel, and the physical channel. At this time, the RB means a service provided by the second layer for data transmission between the UE and the E-UTRAN.

Hereinafter, RACH (Random Access Channel) will be described in detail. The RACH channel is used to transmit data of a short length upstream, and is used when there is a signaling message or user data that a UE that has not been allocated a dedicated radio resource should transmit upward. Or, the BS may be used when it instructs the UE to perform the RACH process.

The following is a description of a random access procedure provided by the LTE system. The random access procedure provided by the LTE system is divided into a contention based random access procedure and a non-contention based random access procedure. The division between the contention-based random access procedure and the contention-based random access procedure is determined according to whether the terminal directly selects a random access preamble used in the random access procedure or whether the base station selects the random access preamble.

In the non-contention-based random access procedure, the UE uses a random access preamble that the BS directly assigns to itself. Therefore, when the BS only allocates the specific random access preamble to the MS, the random access preamble is used only by the MS, and the MS does not use the random access preamble. Therefore, since a 1: 1 relationship is established between the random access preamble and the terminal using the random access preamble, it can be said that there is no collision. In this case, as soon as the base station receives the random access preamble, it can know the terminal that transmitted the random access preamble, which is efficient.

On the other hand, in the contention-based random access procedure, there is a possibility that a plurality of terminals always use the same random access preamble because they arbitrarily select and transmit random access preambles available for the terminal. Therefore, even if the base station receives a specific random access preamble, it can not know which terminal transmitted the random access preamble.

In general, a UE can perform a random access procedure in the following cases. 2) the UE initially accesses the target cell during the handover process; 3) when the UE is requested by an instruction from the base station; and 4) when the UE makes initial access without connection with the base station (RRC Connection) 5) When data is generated in the uplink in a situation where the time synchronization of the uplink does not match or a designated radio resource used for requesting radio resources is not allocated 5) Radio link failure or handover In the case of a recovery process in case of a handover failure.

Based on the above description, FIG. 4 shows an operation procedure of the UE and the BS in the contention-based random access procedure.

First, in a contention-based random access, a UE randomly selects one random access preamble from a set of random access preambles indicated through system information or a handover command, and transmits the random access preamble Selects a PRACH resource and transmits it to the base station. (Step 1) The preamble at this time is called RACH MSG 1.

After the UE transmits the random access preamble as described above, the UE attempts to receive a response to its random access preamble in the random access response reception window indicated by the system information or the handover command (step 2). More specifically, the random access response information is transmitted in the form of a MAC PDU, and the MAC PDU may be delivered to a physical downlink shared channel (PDSCH). In addition, a Physical Downlink Control Channel (PDCCH) is also transmitted together with the PDSCH to properly receive the information transmitted on the PDSCH. That is, the PDCCH may include information of a UE receiving the PDSCH, frequency and time information of the PDSCH, and a transmission format of the PDSCH. Here, if the UE succeeds in receiving the PDCCH coming to the UE itself, the UE properly receives a random access response transmitted on the PDSCH according to the information of the PDCCH. The random access response includes a random access preamble identifier (ID), a UL Grant (uplink radio resource), a Temporary C-RNTI (temporary cell identifier), and a Time Alignment Command (time synchronization correction value). The reason why the random access preamble separator is necessary is that random access response information for one or more UEs can be included in one random access response. Therefore, it is possible to determine to which UE the UL Grant, Temporary C-RNTI and Time Alignment Command information is valid It is to inform. The random access preamble identifier corresponds to the random access preamble selected in step 1 by itself.

Herein, when the UE receives a random access response, the UE processes the information included in the random access response. That is, the UE applies Time Alignment Command and stores a Temporary C-RNTI. In addition, using UL Grant, data stored in the buffer of the UE or newly generated data is transmitted to the BS (step 3). At this time, the identifier of the UE must be included in the data included in the UL Grant (hereinafter referred to as message 3). This is because, in the contention-based random access procedure, the base station can not determine which UEs perform the random access procedure, and it is necessary to identify the UE in order to resolve the collision later. Here, there are two methods of including the identifier of the terminal. In the first method, if the UE has a valid cell identifier already allocated in the corresponding cell before the random access procedure, the UE transmits its cell identifier through the UL Grant. On the other hand, if a valid cell identifier is not allocated before the random access procedure, the UE transmits its own unique identifier (e.g., S-TMSI or Random Id). In general, the unique identifier is longer than the cell identifier. In step 3, if the UE transmits data through the UL Grant, the UE starts a contention resolution timer for a conflict resolution.

After the UE transmits data including its own identifier through the UL Grant included in the random access response, the UE waits for an instruction from the BS to resolve the conflict. That is, the PDCCH is attempted to receive a specific message (step 4). There are two methods of receiving the PDCCH. As described above, when the UE's own identifier transmitted through the UL Grant is a cell identifier, it attempts to receive the PDCCH using its cell identifier. If the identifier is a unique identifier, And attempts to receive the PDCCH using the Temporary C-RNTI. Thereafter, in the former case, if the PDCCH (hereinafter referred to as message 4) is received via its cell identifier before the conflict resolution timer expires, the terminal determines that the random access procedure has been normally performed, The process ends. In the latter case, if the PDCCH is received through the temporary cell identifier before the collision resolution timer expires, data (hereinafter referred to as message 4) transmitted by the PDSCH indicated by the PDCCH is checked. If the unique identifier is included in the contents of the data, the terminal normally determines that the random access procedure has been performed and terminates the random access procedure. Here, the message or MAC PDU received in the fourth step is often referred to as RACH MSG 4.

The following describes a method in which the UE receives downlink data in the LTE system. 5 is an exemplary diagram illustrating radio resource allocation according to the prior art.

In the downward direction, the physical channels are divided into two types: Physical Downlink Control Channel (PDCCH) and Physical Downlink Shared Channel (PDSCH). The PDCCH is not directly related to the transmission of the user data, and control information necessary for operating the physical channel is transmitted. In the simplest case, the PDCCH may be used to control other physical channels. In particular, the PDCCH is used for transmission of information necessary for the UE to receive the PDSCH. At a certain point in time, information such as which data is transmitted using a particular frequency band, which terminal, what size of data is transmitted, and the like is transmitted through the PDCCH. Accordingly, each terminal receives a PDCCH in a specific TTI, checks whether data to be received is transmitted through the PDCCH, and if it is notified that data to be received is transmitted, And further receives the PDSCH. PDSCH data is transmitted to a terminal (one or a plurality of terminals), and information on how to receive and decode PDSCH data is transmitted through a Physical Downlink Control Channel (PDCCH) As shown in FIG.

For example, in a specific subframe, radio resource information (e.g., frequency position) A and transmission format information B (e.g., transport block size, modulation and coding information) Temporary Identity) and transmitted through the PDCCH. One or more UEs in the corresponding cell monitor the PDCCH using RNTI information of its own. In the above assumption, a CRC error is generated when the UE decodes the PDCCH with an RNTI of C . Accordingly, the UE receives the data by decoding the PDSCH using the B format transmission format information and the A radio resource information. On the other hand, in the above assumption, in a terminal that does not have an RNTI of C, a CRC error occurs when the PDCCH is decoded. Therefore, the UE does not receive the PDSCH.

In this process, a Radio Network Temporary Identifier (RNTI) is transmitted in order to inform which UEs the radio resources are allocated through each PDCCH. The RNTI includes a dedicated RNTI and a common RNTI. A dedicated RNTI is allocated to one terminal and is used for transmission and reception of data corresponding to the terminal. The dedicated RNTI is allocated only to a terminal in which information is registered in the base station. On the contrary, the common RNTI is used when the UEs whose information is not registered in the base station and have not been assigned a dedicated RNTI exchange data with the base station, or when they transmit information commonly applied to a plurality of UEs, such as system information.

As mentioned above, the two axes constituting the E-UTRAN are the base station and the terminal. The radio resources in one cell are composed of uplink radio resources and downlink radio resources. The base station is responsible for allocation and control of uplink radio resources and downlink radio resources of the cell. That is, the base station determines at what instant which terminal uses which radio resource. For example, the base station may decide to assign a frequency of 100 MHz to 101 Mhz after 3.2 seconds to user 1 for 0.2 second for downlink data transmission. After making the decision, the base station notifies the corresponding terminal of the fact that the terminal receives the downlink data. Likewise, the base station determines when a certain mobile station will transmit data using a certain amount of radio resources. The base station informs the mobile station of the determination, and the mobile station transmits data using the radio resource for the predetermined time .

Unlike the conventional method, the base station manages radio resources dynamically, thereby enabling efficient use of radio resources. In the conventional technology, one terminal continuously uses one radio resource while a call is connected. This is unreasonable especially considering that many services in recent years are based on IP packets. This is because most packet services do not consistently generate packets during the connection time of the call, but there are many sections that do not transmit anything during the call. In this case, it is inefficient to continuously allocate radio resources to one UE. In order to solve this problem, the E-UTRAN system uses a method of allocating radio resources to the mobile station only in the same manner while the service data is available only when the mobile station is required.

More specifically, in an LTE system, in order to efficiently use radio resources, a base station must know how much data to transmit to each user. In the case of downlink data, this downlink data is transmitted from the access gateway to the base station. Therefore, the base station knows how much data should be transmitted on the downlink to each user. On the contrary, in the case of data in the uplink, if the terminal does not directly inform the base station about the data to be transmitted on the uplink, the base station can not know how much of the uplink radio resource each terminal requires. Therefore, in order for the base station to appropriately allocate the uplink radio resource to the mobile station, each mobile station must provide the base station with information necessary for scheduling the radio resources.

To this end, the MS informs the BS of data to be transmitted, and the BS transmits a Resource Allocation Message to the MS based on the information.

When the UE informs the BS of the data to be transmitted, the UE informs the BS of the amount of data accumulated in its buffer. This is called a Buffer Status Report (BSR).

The buffer status information is generated in the form of a MAC Control Element (MAC CE), is included in a MAC PDU (Protocol Data Unit), and is transmitted from the UE to the BS. That is, uplink radio resources are required to transmit the buffer status information. This means that uplink radio resource allocation request information for transmitting buffer status information should be sent. When the buffer status information is generated, if there is an allocated uplink radio resource, the UE immediately transmits buffer status information using the uplink radio resource. However, when the buffer status information is generated, if there is no allocated uplink radio resource, the UE performs a resource allocation request (SR process: Scheduling Request Procedure).

There are two SR processes, one is a dedicated scheduling request channel (D-SR) set in a physical uplink control channel (PUCCH) resource, and another is a random access channel (RACH) process. That is, if the SR process is triggered, the UE sends a radio resource allocation request using the D-SR channel if the D-SR channel is allocated, and if the D-SR channel is not allocated, Start. When the D-SR channel is used, the resource request allocation signal is transmitted in the upward direction through the D-SR channel.

The SR process continues until the UE receives the UL-SCH resource.

In this process, the buffer status information transmitted by the mobile station informs the buffer amount per logical channel group (LCG), rather than sending information on the amount of buffers for each logical channel. That is, the amount of the buffer is calculated for each group designated by the base station. Up to four LCGs are defined for one terminal. In the above process, there are two types of buffer status information. One is the Long Buffer Status Report (Long BSR) and the other is the Short Buffer Status Report (Short BSR). Long BSR contains information about the amount of buffer for all four LCGs, and Short BSR contains information about the amount of buffer for only one LCG.

The above-described conventional radio resource allocation request method has the following problems. Generally, a plurality of terminals exist in one cell, and a base station allocates radio resources from a terminal having a high priority and a channel having a high priority. Accordingly, in some cases, the base station may not allocate a radio resource to the UE even though the UE has received a radio resource request message or buffer status information from a specific UE. In this case, if the mobile station continuously sends a radio resource allocation request, it causes waste of uplink radio resources and causes interference of radio resources. In addition, in the above case, the base station can directly allocate radio resources to the UE during the RACH process. For example, in a state where the second step of the RACH process is completed, the UE can receive a radio resource from the BS using its own dedicated identifier. However, the second message of the RACH process also has information for allocating radio resources to the UE that has performed the RACH process. In this case, if the UE continuously performs the RACH process, the radio resource allocated using the dedicated identifier is wasted. Also, the D-SR channel is effective only when the UE is synchronized in the upward direction (Synchronized). That is, if the mobile station is not synchronized in the upward direction, the base station can not properly receive the radio resource allocation request of the mobile station even if the mobile station uses the D-SR channel. In this case, the UE continues to transmit the radio resource allocation request without considering such a situation, only interference of radio resources occurs.

Accordingly, it is an object of the present invention to provide a method for efficiently requesting a radio resource to a base station while minimizing interference of radio resources.

According to an aspect of the present invention, there is provided a method of processing a scheduling request (SR) on a wireless communication system, the method comprising: determining whether the scheduling request is triggered; If the uplink control channel is configured to transmit the scheduling request, transmitting the scheduling request on the uplink control channel, or if the uplink control channel is configured to transmit the scheduling request If not, initiating a random access channel procedure; Monitoring a downlink control channel; Determining whether an identifier of the UE is received through the downlink control channel; And stopping the scheduling request triggering if it is determined that the identifier of the UE has been received.

Preferably, the uplink control channel is a Physical Uplink Control Channel (PUCCH).

Preferably, the downlink control channel is a Physical Downlink Control Channel (PDCCH).

Advantageously, the step of transmitting the scheduling request on the uplink control channel or starting the random access channel process is performed when it is determined that the scheduling request is triggered.

Preferably, the identifier of the UE is a Cell-Radio Network Temporary Identifier (C-RNTI).

Preferably, the mobile station continuously performs the scheduling request triggering if it is determined that the identifier of the mobile station has not been received.

Also, in order to solve the above problem, a method of performing a random access channel (RACH) procedure on a wireless communication system according to the present invention includes transmitting a random access channel preamble (RACH preamble) ; Monitoring a downlink control channel after the RACH preamble is transmitted; Determining whether an uplink allocation resource is received together with an identifier of the UE through the downlink control channel, the uplink allocation resource being used to transmit the next scheduled data; And stopping the random access channel process if it is determined that the uplink resource is received together with the identifier of the UE.

Preferably, the downlink control channel is a Physical Downlink Control Channel (PDCCH).

Preferably, the uplink resource is UL-GRANT.

Preferably, the identifier of the UE is a Cell-Radio Network Temporary Identifier (C-RNTI).

Preferably, the RACH process is continuously performed if it is determined that the uplink resource is not received together with the identifier of the UE.

Advantageously, in the step of receiving a response message in response to the transmitted RACH preamble, the response message further comprises another uplink allocation resource.

Preferably, if it is determined that the uplink allocation resource is received together with the identifier of the UE, the uplink allocation resource is discarded.

In the present invention, when the UE performs the buffer status information or the SR process in the base station, a method of effectively using the radio resources is provided, thereby enabling the UE to more quickly and accurately receive the radio resources from the base station.

1 is a network structure of an E-UMTS which is a conventional mobile communication system to which the present invention is applied.
2 is a control plane structure of a wireless interface protocol between a terminal based on the 3GPP radio access network standard and a UTRAN (UMTS Terrestrial Radio Access Network).
3 is a user plane structure of a wireless interface protocol between a terminal based on the 3GPP radio access network standard and a UTRAN (UMTS Terrestrial Radio Access Network).
4 is an exemplary diagram illustrating a contention-based random access procedure.
5 is an exemplary diagram illustrating radio resource allocation according to the prior art.
6 is an exemplary diagram illustrating an operation method used by a terminal for transmitting buffer status information to a base station according to an embodiment of the present invention
7 is an exemplary diagram illustrating a method for a UE in a random access procedure to transmit buffer status information to a Node B in accordance with the present invention

The present invention is applied to 3GPP communication technology, in particular Universal Mobile Telecommunications System (UMTS) system, communication device and communication method. However, the present invention is not limited thereto and may be applied to all wired / wireless communication to which the technical idea of the present invention can be applied.

A basic concept of the present invention is a method for processing a scheduling request (SR) on a wireless communication system, the method comprising: determining whether the scheduling request is triggered; If the uplink control channel is configured to transmit the scheduling request, transmitting the scheduling request on the uplink control channel, or if the uplink control channel is configured to transmit the scheduling request If not, initiating a random access channel procedure; Monitoring a downlink control channel; Determining whether an identifier of the UE is received through the downlink control channel; And stopping the scheduling request triggering if it is determined that the identifier of the UE has been received. The method of processing a scheduling request (SR) on a wireless communication system, The present invention relates to a wireless mobile communication terminal.

According to the present invention there is also provided a method of performing a random access channel (RACH) procedure on a wireless communication system, the method comprising: transmitting a random access channel preamble (RACH preamble); Monitoring a downlink control channel after the RACH preamble is transmitted; Determining whether an uplink allocation resource is received together with an identifier of the UE through the downlink control channel, the uplink allocation resource being used to transmit the next scheduled data; And stopping the random access channel process if it is determined that the uplink resource has been received together with the identifier of the UE. The random access channel procedure (RACH procedure) And proposes a wireless mobile communication terminal capable of performing such a method.

Hereinafter, configurations and operations of embodiments according to the present invention will be described with reference to the accompanying drawings.

As described above, the present invention proposes a method for efficiently requesting a radio resource to a base station while reducing interference of radio resources to a minimum. In order to achieve the above object, according to the present invention, when a terminal requests a radio resource to a base station using a D-SR channel, the terminal transmits a radio resource request to the base station through a D-SR channel for a pre- If the uplink radio resource is not allocated, the radio resource requesting process using the D-SR channel is no longer performed. Preferably, in this process, the UE transitions to a radio resource requesting process using the RACH process. In the above procedure, if a radio resource is allocated to the base station while the D-SR channel is not used a predetermined number of times, the terminal immediately stops the radio resource requesting process. In this case, the D-SR channel is unset and is not used any more.

In order to efficiently transmit buffer state information to the base station, the terminal considers the priorities of the logical channels and the priorities of the other logical channels, when data arrives newly on a certain logical channel, It is suggested that you decide whether to transmit status information or not.

Specifically, the first operation method (Approach 1) according to the present invention is as follows. For any logical channel that previously had no data in the buffer, the terminal checks the priority (A) of the logical channel when data arrives newly in the logical channel. Then, the UE confirms the logical channel group to which the logical channels belong, for all the other logical channels in which data is stored in the buffer. For each of the logical channels belonging to the identified logical channel group, the priority (B) of each of the logical channels is checked regardless of whether there is data in the buffer of the logical channels or not. The UE then compares the priority A with the priority B and triggers the buffer status information to be transmitted to the base station when the priority A is higher than the priority B . Preferably, in this process, only the priority of logical channels having the highest priority in the logical channel groups may be compared.

Specifically, the second operation method (Approach 2) according to the present invention is as follows. For any logical channel that previously had no data in the buffer, the terminal checks the priority (A) of the logical channel when data arrives newly in the logical channel. Then, the terminal checks the priority (B) of each of the logical channels with respect to all other logical channels in which data is present in the buffer. The UE then compares the priority A with the priority B and triggers the buffer status information to be transmitted to the base station when the priority A is higher than the priority B .

The resultant difference between the first operating method and the second operating method is illustrated in Figure 6

That is, according to the first operation method, when data newly arrives in the first logical channel, since the priority of the first logical channel is not higher than that of any other logical channel (the fourth logical channel) Do not trigger information. However, according to the second operation method, when data newly arrives in the first logical channel, the priority of the first logical channel is different from the priority of the other logical channel (third logical channel) And triggers the buffer status information.

 Specifically, the third operation method (Approach 3) according to the present invention is as follows. For a logical channel in which there is no data in the buffer before, when the data newly arrives in the logical channel, the terminal checks the priority (A) of the logical channel and also confirms what logical channel group the logical channel belongs to do. Then, the terminal checks the logical channels that have data in the buffer among the logical channels belonging to the logical channel group. The terminal does not trigger new buffer state information when buffer information has already been delivered to the base station for the logical channel group or logical channels.

Specifically, the fourth operation method (Approach 4) according to the present invention is as follows. For a logical channel in which there is no data in the buffer before, when the data newly arrives in the logical channel, the terminal checks the priority (A) of the logical channel and also confirms what logical channel group the logical channel belongs to do. Then, the terminal checks the logical channels that have data in the buffer among the logical channels belonging to the logical channel group. If the buffer information has already been transmitted to the base station for the logical channel group or the logical channels, the UE newly determines whether the buffer amount accumulated in the logical channel group after the buffer status information is transmitted to the base station exceeds the reference value And triggers new buffer status information only when the reference value is exceeded.

Specifically, a fifth operation method (Approach 5) according to the present invention is as follows. For a logical channel in which there is no data in the buffer before, when the data newly arrives in the logical channel, the terminal checks the priority (A) of the logical channel and also confirms what logical channel group the logical channel belongs to do. Then, the terminal checks the priority (B) of the logical channels that have data in the buffer among the logical channels belonging to the logical channel group. If the priority A is higher than the priority B, the terminal triggers new buffer status information.

Specifically, a sixth operation method (Approach 6) according to the present invention is as follows. For a logical channel in which there is no data in the buffer before, when the data newly arrives in the logical channel, the terminal checks the priority (A) of the logical channel and also confirms what logical channel group the logical channel belongs to do. Then, the UE checks the priority (B) of each logical channel regardless of whether or not it has data in the buffer among all the logical channels belonging to the logical channel group. If the priority A is higher than the priority B, the terminal triggers new buffer status information.

Specifically, the seventh operation method (Approach 7) according to the present invention is as follows. When data newly arrives in the logical channel for a logical channel in which there is no data in the buffer previously, the terminal determines the priority of the logical channel having the highest priority among the logical channels belonging to the logical channel group to which the logical channel belongs A). For each of the other logical channel groups set, the priority B of the logical channel having the highest priority among the logical channels belonging to the respective logical channel groups is checked. The terminal compares the priority A and the priority B and when the priority A is higher than the priority B, the terminal triggers the buffer state information and transmits the buffer state information to the base station. Preferably, in this process, logical channels without data can be excluded from the comparison.

In this process, the buffer status information for the other logical channel group is the same, and when the buffer status information for only a specific logical channel group is changed, the terminal can use the Short BSR.

In addition, in order to allow the UE to efficiently transmit buffer status information to the BS, when the SR process is started in the present invention, the UE starts the RACH process when there is no D-SR channel allocated to the UE. In the second step of the RACH process, the UE receives UL-SCH resources to be used in the third step. However, in the case of the contention-based RACH process, the UE can not know whether the data transmitted by the UE has been successfully transmitted to the BS until the contention is successfully completed in the fourth step. Therefore, the MS having started the SR process proposes not to stop the SR process even if the uplink radio resource is allocated through the third step of the RACH process. FIG. 7 is a diagram illustrating an exemplary method of transmitting buffer status information to a Node B in a random access procedure according to the present invention. Referring to FIG. That is, as shown in FIG. 7, only when the UE receives the GRANT using its C-RNTI in the fourth stage of the RACH, it considers that the SR process is successfully completed. That is, only when the C-RNTI of the asset is received via the Physical Downlink Control Channel (PDCCH), it is considered that the SR process is successfully completed and the SR process is stopped. If the UE does not receive the GRANT using its C-RNTI in the fourth stage of the RACH, the SR process is continuously executed without stopping.

Although the base station recognizes that there is data to be transmitted by a specific terminal according to the amount of available radio resources existing in one cell or the scheduling algorithm used by the eNB (e-NodeB) May not allocate radio resources to the mobile station. Therefore, in this case, the UE rapidly sends another buffer status information, or performs the SR process, resulting in waste of radio resources. Or even if the process of transmitting the SR process or the buffer status information is being performed. Therefore, when a dedicated radio resource is allocated from a base station, i.e., an uplink radio resource is allocated through a C-RNTI during a RACH process due to buffer state information transmission or SR process , The terminal immediately suggests to stop the RACH process. In the present invention, when the SR process is started, when the dedicated radio resource is allocated from the base station, that is, until the radio resource is allocated in the upward direction through the C-RNTI, do. Preferably, when the UE allocates radio resources to be used in the third stage of the RACH in the second stage of the RACH and simultaneously allocates radio resources on the PDCCH through its C-RNTI, the UE allocates We suggest using the received radio resources. At this time, if necessary, the BSR is transmitted using the radio resource. Preferably, when the UE allocates radio resources to be used in the third stage of the RACH in the second stage of the RACH and simultaneously allocates radio resources on the PDCCH through its C-RNTI, To use the allocated radio resources. At this time, if necessary, the BSR is transmitted using the radio resource.

Hereinafter, a terminal according to the present invention will be described.

A terminal according to the present invention includes all types of terminals capable of using a service for exchanging data with each other over wireless. That is, the terminal according to the present invention may include a mobile communication terminal (e.g., a UE, a mobile phone, a cellular phone, a DMB phone, a DVB-H phone, a PDA phone, a PTT phone, And laptops, laptop computers, digital TVs, GPS navigation, portable gaming devices, MP3 and other consumer electronics, and the like.

The terminal according to the present invention may include a basic hardware configuration (a transmission / reception unit, a processing unit or a control unit, a storage unit, and the like) necessary for performing functions and operations for using radio resources more efficiently as illustrated in the present invention.

The method according to the present invention described so far can be implemented in software, hardware, or a combination thereof. For example, the method according to the present invention can be stored in a storage medium (e.g., a mobile terminal or a base station's internal memory, flash memory, hard disk, etc.) Lt; / RTI > may be implemented as codes or instructions within a software program that may be executed by a processor (e.g., an internal microprocessor).

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the scope of the present invention . Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

Claims (8)

A method for requesting a scheduling request for an uplink shared channel (UL-SCH) resource in a wireless communication system, the method comprising:
Determining whether an existing UL-SCH resource is allocated to a C-RNTI (Cell-Radio Network Temporary Identifier) of the UE; And
If it is determined that the existing UL-SCH resource is not allocated,
Triggering the scheduling request;
Determining whether a Physical Uplink Control Channel (PUCCH) is configured for the terminal;
If the PUCCH is configured for the UE, the scheduling request is transmitted a predetermined number of times through the PUCCH, and a PDCCH (Physical Downlink Control Channel) is transmitted for a new UL-SCH resource allocated to the C-RNTI of the UE Monitoring; And
And if the PUCCH is not configured for the terminal, initiating a random access procedure to obtain the new UL-SCH resource
A method for requesting a scheduling request for a UL-SCH resource in a wireless communication system. 2. The method of claim 1, wherein monitoring the PDCCH comprises:
And releasing the PUCCH if the new UL-SCH resource is not received after the predetermined number of times. 2. The method of claim 1, wherein initiating the random access procedure comprises:
And stopping the random access procedure if any UL-SCH resources are received during the random access procedure. ≪ Desc / Clms Page number 19 > 3. The method of claim 1, further comprising repeating the operation until the new UL-SCH resource is obtained. 3. A method of requesting a scheduling request for a UL-SCH resource in a wireless communication system. A terminal configured to request a scheduling request for UL-SCH resources in a wireless communication system,
A transmission / reception unit; And
A processor operatively connected to the transceiver;
Lt; / RTI >
The processor comprising:
Determines whether an existing UL-SCH resource is allocated to the C-RNTI of the UE,
If it is determined that the existing UL-SCH resource is not allocated,
Triggering a scheduling request,
Determines whether a PUCCH is configured for the terminal,
If the PUCCH is configured for the UE, transmits the scheduling request a predetermined number of times through the PUCCH, monitors the PDCCH for a new UL-SCH resource allocated to the C-RNTI of the UE,
And initiate a random access procedure to obtain the new UL-SCH resource if the PUCCH is not configured for the terminal. 6. The terminal of claim 5, wherein the processor is configured to release the PUCCH if the new UL-SCH resource is not received after the predetermined number of times. 6. The UE of claim 5, wherein the processor is configured to suspend the random access procedure if any UL-SCH resources are received during the random access procedure. 6. The terminal of claim 5, wherein the processor is configured to repeat the operation until the new UL-SCH resource is obtained.

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