Abstract:
A method and device for triggering and reporting an SR are disclosed in the present invention. The present invention adds determining of UL-SCH resource scheduling grant and subsequent UL-SCH resource to the process of SR triggering and reporting; with the present invention, the current status of a UE can be accurately determined, and only a necessary SR is triggered and reported. Therefore, not only system overhead can be saved, but also it can be avoided that a base station, in order to respond to the unnecessary SR sent by the UE, allocates redundant UL-SCH resource to the UE, moreover, the system bandwidth is also saved and the system frequency spectrum efficiency is improved.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to an uplink resource allocation technique in the field of wireless communications, particularly to a method and device for triggering or reporting a scheduling request (SR) in wireless networks. 
       BACKGROUND 
       [0002]    In the evolved universal terrestrial radio access network (E-UTRAN) of the third-generation mobile communication long term evolution (LTE) system, uplink data is transmitted via an uplink shared channel (UL-SCH), and uplink resource is allocated to user equipment (UE) by a base station. Dedicated uplink control signaling is formulated for the user&#39;s uplink transmission demand in the LTE system. In the uplink control signaling, the control signaling in relation to uplink radio resource management contains an SR and a buffer status report (BSR) of UE. 
         [0003]    In the LTE media access control (MAC) layer protocol, the condition of triggering SR is specified as follows: if a UE triggers a BSR for the first time, or triggers a BSR again after it sends a BSR last time, then if the UE does not have allocated uplink resource which can be used for the first transmission in the current transmission time interval (TTI) and the BSR is a regular BSR, an SR will be triggered. An SR triggering process in the prior art is shown in  FIG. 1 , and the specific process is as follows. 
         [0004]    Step  101 , confirming the UE triggers a BSR for the first time, or triggers a BSR again after it sends a BSR last time. 
         [0005]    Steps  102 ˜ 103 , determining whether the UE has available allocated UL-SCH resource in the current TTI. If yes, Step  103  will be executed and the BSR will be sent in the allocated UL-SCH resource; if no, Step  105  will be executed. 
         [0006]    Step  104 , cancelling all other triggered BSRs. Then Step  107  will be executed and wait for next TTI. 
         [0007]    Steps  105 ˜ 106 , determining whether the triggered BSRs contain a regular BSR. If yes, Step  106  will be executed and an SR will be triggered; if no, Step  107  will be executed and next TTI will be waited for. 
         [0008]    An uplink control channel is needed for SR reporting, the uplink control channel resource is allocated to the UE by the base station in advance.  FIG. 2  is a schematic flowchart illustrating SR reporting in the prior art. As shown in  FIG. 2 , the specific processing process includes the following steps. 
         [0009]    Step  201 , the UE triggers an SR. 
         [0010]    Step  202 , determining whether the UE has available allocated UL-SCH resource in the current TTI. If yes, Step  203  will be executed; if no, Step  205  will be executed. 
         [0011]    Steps  203 ˜ 204 , determining whether the UE has received UL-SCH resource to scheduling grant in the current TTI. If yes, all SRs waiting for being processed will be cancelled; if no, Step  211  will be executed, next TTI will be waited for and continued determining will be performed. 
         [0012]    Steps  205 ˜ 206 , determining whether no uplink control channel resource that can be used for sending an SR has been allocated to the UE in any TTI. If yes, a random is access process will be started and all SRs waiting for being processed will be cancelled; if no, Step  207  will be executed. 
         [0013]    Step  207 , determining whether the UE has the uplink control channel resource that can be used for sending an SR in the current UI. If yes, Step  208  will be executed; if no, Step  211  will be executed, next TTI will be waited for and continued determining will be performed. 
         [0014]    Step  208 , determining whether the maximum number of SR sending times is reached. If the UE does not receive the UL-SCH resource scheduling grant from the base station in a fixed period, i.e. when there is no available UL-SCH resource, the UE will send an SR many a time until the maximum number of SR sending times is reached. If the maximum number of sending times is reached, Step  209  will be executed; if the maximum number of sending times is not reached, Step  210  will be executed. 
         [0015]    Step  209 , the UE releases the uplink control channel resource, starts a random access process and cancels all SRs waiting for being processed. 
         [0016]    Step  210 , sending the SR on the uplink control channel, then Step  211  will be executed and next TTI will be waited for. 
         [0017]    As shown in  FIG. 1  and  FIG. 2 , the SR triggering and sending mechanism prescribed in the current LTE MAC layer protocol is imperfect. There is still a time interval from the time when the UE receives resource scheduling grant fed back by the base station to the time when the UE has available UL-SCH resource. When a regular BSR is triggered in this time interval, an SR will be triggered subsequently. Moreover, if the UE has an available uplink control channel in this time interval, the SR will be sent. However, as the UE has received the resource scheduling grant fed back by the base station, therefore the sending of the SR is totally unnecessary.  FIG. 3  is a time sequence diagram illustrating SR triggering and reporting according to an embodiment of the prior art. As shown in the figure, a box in the figure stands for a TTI of the time sequence, and uplink control channel resource, which is used for sending an SR to the base station by the UE, is allocated to the UE by the base station every 5 TTIs, i.e. the sending period of an SR is five TTIs. 
         [0018]    Event  301 , a UE triggers a regular BSR 1 , and then triggers an SR 1 . 
         [0019]    Event  302 , when an SR sending period arrives, the UE sends the SR 1  to the base station, to request UL-SCH resource scheduling grant. 
         [0020]    Event  303 , when another SR sending period arrives, as the UE does not receive the UL-SCH resource scheduling grant, the SR 1  is sent again. 
         [0021]    Event  304 , the UE has received the UL-SCH resource scheduling grant in this TTI, so it cancels the SR 1  waiting for being processed, i.e. the SR 1  is not sent again. 
         [0022]    Event  305 , the UE triggers a regular BSR 2 . As the UE does not have available UL-SCH resource in this TTI, it triggers an SR 2 . 
         [0023]    Event  306 , an SR sending period arrives, so the UE sends the SR 2  in this TTI through an uplink control channel. 
         [0024]    Event  307 , the UE has available UL-SCH resource in this TTI. 
         [0025]    Event  308 , the UE sends the BSR 2 . 
         [0026]    From the foregoing process, it can be seen that the UE has obtained the UL-SCH resource scheduling grant fed back by the base station in the TTI in which Event  304  occurs, so the SR 2  sent in the TTI in which Event  306  occurs is totally unnecessary, thereby resulting in increase of uplink control signaling overhead. Further, as the base station may respond to this SR 2  and reallocate other UL-SCH resource to the UE, therefore system bandwidth will be wasted and system frequency spectrum efficiency will be affected. 
       SUMMARY 
       [0027]    In view of the foregoing reason, the present invention aims to provide a method and device for triggering or reporting a scheduling request (SR) in wireless networks, to reduce system overhead and improve system frequency spectrum efficiency. 
         [0028]    To achieve the foregoing objective, the technical solution of the present invention is realized in the following way. 
         [0029]    The present invention provides a method for triggering a scheduling request (SR), a user equipment (UE) triggers a buffer status report (BSR), the method comprises: 
         [0030]    when it is determined that no uplink shared channel (UL-SCH) resource allocated for a first transmission is available in a current transmission time interval (TTI), and that no UL-SCH resource scheduling grant is obtained and triggered BSRs contain a set type of BSR, an SR is triggered; or 
         [0031]    when it is determined that no UL-SCH resource allocated for a first transmission is is available in the current TTI, and that triggered BSRs contain a set type of BSR and no UL-SCH resource allocated for a first transmission is available in a subsequent TTI, an SR is triggered. 
         [0032]    The present invention also provides a method for reporting an SR, a UE triggers an SR, the method comprises: 
         [0033]    the UE determines whether UL-SCH resource allocated for a first transmission is available in a current TTI; If yes, all SRs waiting for being processed is cancelled; if no, the SR is sent on an uplink control channel when it is determined that uplink control channel resource which can be used for sending an SR has been allocated to the UE, and that there is the uplink control channel resource which can be used for sending an SR in the current HI and a maximum number of SR sending times is not reached. 
         [0034]    Before the UE triggers the SR, the method may further comprise: 
         [0035]    the UE triggers a BSR, when it is determined that no UL-SCH resource allocated for the first transmission is available in the current TTI, and that no UL-SCH resource scheduling grant is obtained and triggered BSRs contain a set type of BSR, an SR is triggered; or 
         [0036]    when it is determined that no UL-SCH resource allocated for the first transmission is available in the current TTI, and that the triggered BSRs contain a set type of BSR and no UL-SCH resource allocated for the first transmission is available in a subsequent an SR is triggered. 
         [0037]    The present invention also provides a device for triggering an SR, the device comprises: 
         [0038]    a BSR triggering module, which is used for triggering a BSR; 
         [0039]    a resource determining module, which is used for determining no UL-SCH resource allocated for a first transmission is available in a current TTI; 
         [0040]    the device further comprises: 
         [0041]    a grant determination module, which is used for determining that no UL-SCH resource scheduling grant is obtained when no UL-SCH resource allocated for the first transmission is available in the current TTI; 
         [0042]    a BSR determining module, which is used for determining that BSRs contain a set type of BSR when it is determined that no UL-SCH resource scheduling grant is obtained; 
         [0043]    an SR triggering module, which is used for triggering an SR when it is determined that the BSRs contain a set type of BSR; 
         [0044]    or the device further comprises: 
         [0045]    a BSR determining module, which is used for determining that BSRs contain a set type of BSR when no UL-SCH resource allocated for the first transmission is available in the current TTI; 
         [0046]    a subsequent resource determining module, which is used for determining that no UL-SCH resource allocated for the first transmission is available in a subsequent TTI when it is determined that the BSRs contain a set type of BSR; 
         [0047]    an SR triggering module, which is used for triggering an SR when no UL-SCH resource allocated for the first transmission is available in the subsequent TTI. 
         [0048]    The present invention also provides a device for reporting an SR, the device comprises: 
         [0049]    a determining module, which is used for determining whether a UE has available UL-SCH resource allocated for a first transmission in a current TTI, and obtaining a determining result; 
         [0050]    a channel determining module, which is used for determining that uplink control channel resource that can be used for sending an SR has been allocated to the UE and there is the uplink control channel resource that can be used for sending an SR in the current TTI when the determining result of the determining module is no; 
         [0051]    an SR sending module, which is used for determining that a maximum number of SR sending times is not reached and sending an SR on an uplink control channel when there is the uplink control channel resource that can be used for sending an SR in the current TTI. 
         [0052]    The device may further comprise: 
         [0053]    an SR cancelling module, which is used for cancelling all SRs waiting for being processed when the determining result of the determining module is yes. 
         [0054]    The device may further comprise: 
         [0055]    a BSR triggering module, which is used for triggering a BSR; 
         [0056]    a resource determining module, which is used for determining that no UL-SCH resource allocated for the first transmission is available in the current TTI; 
         [0057]    the device may further comprise: 
         [0058]    a grant determining module, which is used for determining that no UL-SCH resource scheduling grant is obtained when no UL-SCH resource allocated for the first transmission is available in the current TTI; 
         [0059]    a BSR determining module, which is used for determining that BSRs contain a set type of BSR when it is determined that no UL-SCH resource scheduling grant is obtained; 
         [0060]    an SR triggering module, which is used for triggering an SR when it is determined that the BSRs contain a set type of BSR; 
         [0061]    or the device may further comprise: 
         [0062]    a BSR determining module, which is used for determining that BSRs contain a set type of BSR when no UL-SCH resource allocated for the first transmission is available in the current TTI; 
         [0063]    a subsequent resource determining module, which is used for determining that no UL-SCH resource allocated for the first transmission is available in a subsequent TTI when it is determined that the BSRs contain a set type of BSR; 
         [0064]    an SR triggering module, which is used for triggering an SR when no UL-SCH resource allocated for the first transmission is available in the subsequent TTI. 
         [0065]    Compared to the prior art, the present invention makes improvement on the aspects of SR triggering process and SR reporting process respectively, adds determining of UL-SCH resource scheduling grant and subsequent UL-SCH resource and so on; with the present invention, the current status of the UE can be accurately determined, and only a necessary SR is triggered and reported. Therefore, not only system overhead can be saved, but also it can be avoided that the base station, in order to respond to the unnecessary SR sent by the UE, allocates redundant UL-SCH resource to the UE, moreover, the system bandwidth is also saved and the system frequency spectrum efficiency is improved. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0066]      FIG. 1  is a schematic flowchart illustrating SR triggering in the prior art; 
           [0067]      FIG. 2  is a schematic flowchart illustrating SR reporting in the prior art; 
           [0068]      FIG. 3  is a time sequence diagram illustrating SR triggering and reporting according to an embodiment of the prior art; 
           [0069]      FIG. 4  is a schematic flowchart illustrating SR triggering according to Method Embodiment 1 of the present invention; 
           [0070]      FIG. 5  is a schematic flowchart illustrating SR triggering according to Method Embodiment 2 of the present invention; 
           [0071]      FIG. 6  is a schematic flowchart illustrating SR reporting according to a method embodiment of the present invention; 
           [0072]      FIG. 7  is a structural relation schematic diagram illustrating an SR triggering device according to Device Embodiment 1 of the present invention; 
           [0073]      FIG. 8  is a structural relation schematic diagram illustrating an SR triggering device according to Device Embodiment 2 of the present invention; 
           [0074]      FIG. 9  is a structural relation schematic diagram illustrating an SR triggering and reporting device according to Device Embodiment 1 of the present invention; 
           [0075]      FIG. 10  is a structural relation schematic diagram illustrating an SR triggering and reporting device according to Device Embodiment 2 of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0076]    The technical solution of the present invention is described in detail below in combination with the accompanying drawings and embodiments. 
         [0077]    In the LTE system, when a UE has new data which needs to be transmitted on a UL-SCH, it will inform the base station by sending an SR, to request the base station to allocate available UL-SCH resource for a first transmission; after the base station confirms that the UL-SCH resource for the first transmission can be allocated to the UE, it will send preliminary UL-SCH resource scheduling grant to the UE; then the UE will is send a BSR to the base station according to the UL-SCH resource for the first transmission as instructed in the UL-SCH resource scheduling grant, to inform the base station of the volumes of new data waiting for being transmitted and request the base station to allocate an appropriate size of UL-SCH resource for the first transmission. 
         [0078]    Below the SR triggering process in the present invention is described by referring to specific embodiments. 
         [0079]      FIG. 4  is a schematic flowchart illustrating SR triggering according to Method Embodiment 1 of the present invention. As shown in  FIG. 4 , the specific process includes the following steps. 
         [0080]    Step  401 , the UE triggers a BSR for the first time, or triggers a BSR again after it sends a BSR last time. 
         [0081]    When the UE has new data which needs to be transmitted on a UL-SCH, it needs to trigger an SR firstly. In the LTE system, a precondition specified for SR triggering is that: it is required that the UE triggers a BSR for the first time or triggers a BSR again after it sends a BSR last time, and when the UE has no available allocated UL-SCH resource in the current TTI and the triggered BSRs contain a regular BSR, an SR will be triggered. 
         [0082]    In the provision of LTE MAC layer protocol, according to different triggering conditions, BSRs may be divided into three categories: regular BSR, periodic BSR and padding BSR. 
         [0083]    Wherein many types of events can trigger regular BSRs, including: available data is waiting for being transmitted, while the buffer of the UE is empty; available data with higher priority is waiting for being transmitted, while available data waiting for being transmitted in the buffer of the UE is of lower priority; change occurs on the service cell to which the UE belongs; a timer for BSR resending times out, but in the UE, there is available data waiting for being transmitted. 
         [0084]    The events that trigger periodic BSRs include: a periodic BSR timer times out. 
         [0085]    The events that trigger padding BSRs include: the UE has obtained allocated uplink resource, and the number of padding bits is equal to or greater than the size of the control unit of the BSR MAC layer. 
         [0086]    It should be noted that in the present invention, the condition for triggering an SR is not limited to the triggering of a regular BSR and is also applicable to other types of BSRs, of course the condition is also applicable to other events that can trigger SRs. In the present invention, the triggering of a regular BSR is taken as an example to describe the specific process of SR triggering. 
         [0087]    Step  402 , determining whether the UE has available UL-SCH resource allocated for the first transmission in the current TTI. If yes, Step  403  will be executed; if no, Step  405  will be executed. 
         [0088]    It is determined whether the base station has allocated the UL-SCH resource for the first transmission to the UE in the current TTI. 
         [0089]    When UL-SCH resource scheduling grant allocated by the base station is received, there will be related record information in the UE; after the UE receives the grant, it needs a period of decoding time to translate the content of the grant. From the content of the grant, it may be known in which TTI the UE may obtain available UL-SCH resource for the first transmission. Typically, the decoding time is longer than one TTI. 
         [0090]    Step  403 , sending the BSR in the allocated UL-SCH resource. 
         [0091]    When the UE receives the UL-SCH resource for the first transmission which is allocated by the base station, the BSR triggered by the UE will be sent in the TTI through the UL-SCH resource allocated for the first transmission, to inform the base station of the current volumes of the data waiting for being transmitted in the UE and request the base station to allocate an appropriate size of UL-SCH resource to the UE. 
         [0092]    Before a BSR is sent, the UE may have triggered a plurality of BSRs. Which triggered BSR is sent may be selected through a set algorithm. Preferably, the BSR triggered at recent time may be sent, because this BSR can correctly reflect the current volumes of data waiting for being transmitted in the UE. 
         [0093]    Step  404 , cancelling all triggered BSRs, then Step  408  will be executed, and next TTI will be waited for to carry out subsequent operations. 
         [0094]    After the UE sends the BSR to the base station, all BSRs triggered before will be cancelled, to avoid that the UE sends one of these BSRs to the base station again in subsequent processing, which leads to the increase of system overhead; and it is also avoided that the base station responds to this BSR and allocates unnecessary UL-SCL resource to the UE. 
         [0095]    Step  405 , determining whether the UE has obtained UL-SCH resource scheduling grant. If yes, Step  408  will be executed, next TTI will be waited for and when the UE receives the allocated UL-SCH resource, it will send the BSR; if no, Step  406  will be executed. 
         [0096]    If the UE does not receive the UL-SCH resource allocated by the base station in the current TTI, it will be determined whether the UE has obtained the UL-SCH resource scheduling grant sent by the base station up till this TTI. 
         [0097]    Compared to the process in the prior art, the present invention adds the determining step  405 . From the determining step, it may be known whether the UE has obtained UL-SCH resource scheduling grant by now. If yes, it is indicated that the base station has responded to the SR reported by the UE before, and the UE will definitely obtain UL-SCH resource in the n th  TTI numbered from the TTI in which the UE obtains scheduling grant. Therefore, it is not necessary for the UE to trigger and report an SR in the period from the time when the UE acquires UL-SCH resource scheduling grant to the time when the UE acquires UL-SCH resource, thus system overhead is saved. 
         [0098]    Step  406 , determining whether triggered BSRs contain a regular BSR. If yes, Step  407  will be executed; if no, Step  408  will be executed, next TTI will be waited for and continued determining will be performed on whether the UE has available allocated UL-SCH resource. 
         [0099]    Whether the BSR is a regular BSR, or a periodic BSR or other type of BSR may be determined according to the type of the event that triggers the BSR. For example, an identity may be added to the BSR according to the triggering event, and the type of BSR can be identified through the identity. Of course, the method for determining the type of a BSR is not limited to the method described herein. 
         [0100]    Step  407 , triggering an SR. 
         [0101]    The UE triggers an SR according to the triggered regular BSR. 
         [0102]    In order to realize the SR triggering method shown in  FIG. 4 , the present invention provides a device.  FIG. 7  is a structural relation schematic diagram illustrating an SR triggering device according to Device Embodiment 1 of the present invention. The device comprises: 
         [0103]    a BSR triggering module  71 , which is used for triggering a BSR, which specifically means that: the UE triggers a BSR for the first time, or triggers a BSR again after it sends a BSR last time; 
         [0104]    a resource determining module  72 , which is used for determining that no allocated UL-SCH resource is available in the current TTI; 
         [0105]    a grant determining module  73 , which is used for determining that no UL-SCH resource scheduling grant is obtained when it is determined that no allocated UL-SCH resource is available in the current TTI; 
         [0106]    a BSR determining module  74 , which is used for determining that the triggered BSRs contain a set type of BSR when it is determined that no UL-SCH resource scheduling grant is obtained; 
         [0107]    an SR triggering module  75 , which is used for triggering an SR when it is determined that the triggered BSRs contain a regular BSR. 
         [0108]      FIG. 5  is a schematic flowchart illustrating an SR triggering according to Method Embodiment 2 of the present invention. As shown in the figure, the specific processing process includes the following steps. 
         [0109]    Steps  501 ˜ 504  are the same as Steps  401 ˜ 404  in  FIG. 4 , which are not described again here. 
         [0110]    Step  505 , determining whether the triggered BSRs contain a regular BSR. If yes, Step  506  will be executed; if no, Step  508  will be executed, next TTI will be waited for and continued determining will be performed on whether the UE has available allocated UL-SCH resource. 
         [0111]    If the UE does not receive the UL-SCH resource allocated by the base station in the current TTI, it will determine whether the triggered BSRs contain a regular BSR. The determining method in this step is the same as that in Step  406  in  FIG. 4 , which is not described again here. 
         [0112]    Step  506 , determining whether the UE has available UL-SCH resource allocated for the first transmission in a subsequent TTI. If no, Step  507  will be executed; if yes, Step  508  will be executed. 
         [0113]    The base station responds to the SR sent by the UE and sends UL-SCH resource scheduling grant to the UE. When the UE receives the UL-SCH resource scheduling grant, there will be related record information; after the UE receives the grant, it needs is a period of decoding time to translate the content of the grant. From the content of the grant, it may be known in which TTI the UE may obtain available UL-SCH resource for the first transmission. Typically, the decoding time is longer than one TTI. 
         [0114]    In the current TTI, the UE can determine whether it has received the UL-SCH resource scheduling grant sent by the base station up till the current TTI. According to this grant, it may be determined whether the UE can obtain the UL-SCH resource for the first transmission which is allocated by the base station in the subsequent TTI. If it is determined that the UE has available UL-SCH resource allocated for the first transmission in the subsequent TTI, then from the current TTI on, there will be no need to trigger and report the SR again, thereby system overhead is saved. 
         [0115]    If yes, it is indicated that the base station has responded to the SR sent by the UE before, Step  508  will be executed, next TTI will be waited for, and the BSR will be sent in the TTI in which the UL-SCH resource allocated for the first transmission arrives; if no, it is indicated that the base station has not responded to the SR sent by the UE before or the UE has not sent any SR to the base station, Step  507  will be executed and the UE will trigger an SR according to the triggered regular BSR. 
         [0116]    In order to realize the SR triggering method shown in  FIG. 5 , the present invention provides a device.  FIG. 8  is a structural relation schematic diagram illustrating an SR triggering device according to Device Embodiment 2 of the present invention. As shown in  FIG. 8 , the device comprises: 
         [0117]    a BSR triggering module  71 , which is used for triggering a BSR, which specifically means that: the UE triggers a BSR for the first time, or triggers a BSR again after it sends a BSR last time; 
         [0118]    a resource determining module  72 , which is used for determining that no allocated UL-SCH resource is available in the current UI; 
         [0119]    a BSR determining module  74 , which is used for determining that the triggered BSRs contain a set type of BSR when no allocated UL-SCH resource is available in the current TTI; 
         [0120]    a subsequent resource determining module  81 , which is used for determining that no allocated UL-SCH resource is available in a subsequent TTI when it is determined that the triggered BSRs contain a set type of BSR; 
         [0121]    an SR triggering module  75 , which is used for triggering an SR when no allocated UL-SCH resource is available in the subsequent TTI. 
         [0122]    Below the SR reporting process in the present invention is described by referring to specific embodiments. 
         [0123]      FIG. 6  is a schematic flowchart illustrating an SR reporting according to a method embodiment of the present invention. As shown in the figure, the processing process includes the following steps. 
         [0124]    Step  601 , the UE triggers an SR. 
         [0125]    Steps  602 ˜ 603 , determining whether the UE has available UL-SCH resource allocated for the first transmission in the current TTI. If yes, Step  603  will be executed and all SRs waiting for being processed will be cancelled; if no, Step  604  will be executed. 
         [0126]    It is determined whether the UE has available UL-SCH resource allocated for the first transmission in the current TTI after the UE triggers the SR. If yes, it is indicated that the base station has responded to the SR sent by the UE before, and the base station has allocated the UL-SCH resource for the first transmission to the UE, then Step  603  will be executed and all SRs waiting for being processed will be cancelled; if no, Step  604  will be executed. 
         [0127]    Steps  604 ˜ 605 , determining whether no uplink control channel resource that can be used for sending an SR has been allocated to the UE in any TTI. If yes, Step  605  will be executed, a random access process will be started and all SRs waiting for being processed will be cancelled; if no, Step  606  will be executed. 
         [0128]    The UE reports an SR to the base station through uplink control channels, and uplink control channel resource is allocated to the UE by the base station. When uplink control channel resource is allocated to the UE, there will be related record information; or a period for allocating uplink control channel resource to the UE, i.e. SR sending period, may be set according to requirement. One period shall contain one TTI at least. Of course, there may be other methods. According to the information, it may be determined whether uplink control channel resource has been allocated to the UE up till the current TTI. If no, it is indicated that the connection between the UE and the base station may be abnormal, and the UE will start a random access process to establish connection to the base station again, and cancel all SRs waiting for being processed. 
         [0129]    Step  606 , determining whether the UE has the uplink control channel resource that can be used for sending an SR in the current TTI. If no, Step  610  will be executed, next TTI will be waited for and continued determining will be performed on whether the UE has the uplink control channel resource that can be used for sending an SR in the current TTI; if yes, Step  607  will be executed. 
         [0130]    If the uplink control channel resource that can be used for sending an SR has been allocated to the UE, it is indicated that the connection between the UE and the base station is normal, and then it will be determined whether the UE has the uplink control channel resource that can be used for sending an SR in the current TTI. 
         [0131]    Steps  607 ˜ 608 , determining whether the maximum number of SR sending times is reached. If yes, Step  608  will be executed and the UE will release uplink control channel resource, start a random access process and cancel all SRs waiting for being processed; if no, Step  609  will be executed. 
         [0132]    According to requirement, it may be set that SR is sent every n TTIs and the maximum number of SR sending times is m, wherein n and m are natural numbers. When the UE has the uplink control channel resource that can be used for sending an SR in the current TTI, the number of SR sending times will be calculated in the period from the time when the UE sent an SR for the first time to the current TTI. If the number of sending times reaches the maximum number of SR sending times, it is indicated that the connection between the UE and the base station is abnormal and the UE will release the uplink control channel resource, start a random access process and cancel all SRs waiting for being processed; if the number of sending times does not reach the maximum number of SR sending times, Step  609  will be executed. 
         [0133]    Steps  609 ˜ 610 , sending the SR on an uplink control channel, then waiting for next TTI, and circularly executing this process. 
         [0134]    The UE sends the SR through an uplink control channel in the current TTI, i.e. reporting the SR to the base station, and then begins to circularly execute this process in next TTI. 
         [0135]    A process of a method for triggering and reporting an SR can be obtained by combining the process of the SR reporting method shown in  FIG. 6  with the process of the SR triggering method shown in  FIG. 4  or that in  FIG. 5  respectively. In order to realize this process of the method, the present invention provides a device for triggering and reporting an SR.  FIG. 9  is a structural relation schematic diagram illustrating an SR triggering and reporting device according to Device Embodiment 1 of the present invention. As shown in  FIG. 9 , the device comprises: 
         [0136]    a BSR triggering module  71 , which is used for triggering a BSR, which specifically means that: the UE triggers a BSR for the first time, or triggers a BSR again after it sends a BSR last time; 
         [0137]    a resource determining module  72 , which is used for determining that no allocated UL-SCH resource is available in the current TTI; 
         [0138]    a grant determining module  73 , which is used for determining that no UL-SCH resource scheduling grant is obtained when it is determined that no allocated UL-SCH resource is available in the current TTI; 
         [0139]    a BSR determining module  74 , which is used for determining that the triggered BSRs contain a set type of BSR when it is determined that no UL-SCH resource scheduling grant is obtained; 
         [0140]    an SR triggering module  75 , which is used for triggering an SR when it is determined that the triggered BSRs contain a set type of BSR; 
         [0141]    a determining module  91 , which is used for determining whether the UE has available UL-SCH resource allocated for the first transmission in the current TTI after the SR is triggered, and obtaining the determining result; 
         [0142]    an SR cancelling module  92 , which is used for cancelling all SRs waiting for being processed when the determining result of the determining module is yes; 
         [0143]    a channel determining module  93 , which is used for determining that uplink control channel resource that can be used for sending an SR has been allocated to the UE and there is the uplink control channel resource which can be used for sending an SR in the current TTI when the determining result of the determining module is no; 
         [0144]    an SR sending module  94 , which is used for determining that a maximum number of SR sending times is not reached and sending the SR on an uplink control channel when there is the uplink control channel resource that can be used for sending an SR in the current TTI. 
         [0145]      FIG. 10  is a structural relation schematic diagram illustrating an SR triggering and reporting device according to Device Embodiment 2 of the present invention. As shown in the figure, the device comprises: 
         [0146]    a BSR triggering module  71 , which is used for triggering a BSR, which specifically means that: the UE triggers a BSR for the first time, or triggers a BSR again after it sends a BSR last time; 
         [0147]    a resource determining module  72 , which is used for determining that no allocated UL-SCH resource is available in the current TTI; 
         [0148]    a BSR determining module  74 , which is used for determining that the triggered BSRs contain a set type of BSR when no allocated UL-SCH resource is available in the current TTI; 
         [0149]    a subsequent resource determining module  81 , which is used for determining that no allocated UL-SCH resource is available in the subsequent TTI when it is determined that the triggered BSRs contain a set type of BSR; 
         [0150]    an SR triggering module  75 , which is used for triggering an SR when no allocated UL-SCH resource is available in the subsequent TTI; 
         [0151]    a determining module  91 , which is used for determining whether the UE has available UL-SCH resource allocated for the first transmission in the current TTI after the SR is triggered, and obtaining the determining result; 
         [0152]    an SR cancelling module  92 , which is used for cancelling all SRs waiting for being processed when the determining result of the determining module is yes; 
         [0153]    a channel determining module  93 , which is used for determining that uplink control channel resource that can be used for sending SRs has been allocated to the UE and there is the uplink control channel resource that can be used for sending an SR in the current TTI when the determining result of the determining module is no; 
         [0154]    an SR sending module  94 , which is used for determining that the maximum number of SR sending times is not reached and sending the SR on an uplink control channel when there is uplink control channel resource that can be used for sending an SR in the current TTI. 
         [0155]    The foregoing descriptions are preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention.