CN102332970A - A kind of uplink reference signal processing method and base station and terminal - Google Patents

Abstract

Translated fromChinese

本发明提供了一种上行参考信号处理方法，包括：基站接收来自终端的解调参考信号(DMRS)，利用所述DMRS代替探测参考信号(SRS)行使探测(Sounding)功能。本发明同时公开了一种基站和终端。应用本发明所述方案，能够解决SRS资源受限的问题，从而提高系统性能。

The present invention provides an uplink reference signal processing method, comprising: a base station receives a demodulation reference signal (DMRS) from a terminal, and uses the DMRS to replace the sounding reference signal (SRS) to perform sounding (Sounding) function. The invention simultaneously discloses a base station and a terminal. By applying the scheme of the present invention, the problem of limited SRS resources can be solved, thereby improving system performance.

Description

Translated fromChinese

一种上行参考信号处理方法以及基站和终端A kind of uplink reference signal processing method and base station and terminal

技术领域technical field

本发明涉及移动通信技术，特别涉及一种上行参考信号处理方法以及基站和终端。The present invention relates to mobile communication technology, in particular to an uplink reference signal processing method, a base station and a terminal.

背景技术Background technique

现有技术中，一个上行子帧(Subframe)的长度为1ms，包含14或12个符号，在有物理上行共享信道(PUSCH，Physical uplink shared channel)或物理上行控制信道(PUCCH，Physical uplink control channel)传输时，其中的两个符号，如第4和第11个符号用于发送解调参考信号(DMRS，Demodulation Reference Signal)，剩余的符号用来发送PUSCH或PUCCH的数据部分，如上行数据或上行控制信令，DMRS可用来解调上行数据或上行控制信令。如果没有上行数据或上行控制信令需要发送，则不会发送DMRS。In the prior art, an uplink subframe (Subframe) has a length of 1 ms and contains 14 or 12 symbols. When there is a physical uplink shared channel (PUSCH, Physical uplink shared channel) or a physical uplink control channel (PUCCH, Physical uplink control channel) ) transmission, two of the symbols, such as the 4th and 11th symbols, are used to send a demodulation reference signal (DMRS, Demodulation Reference Signal), and the remaining symbols are used to send the data part of PUSCH or PUCCH, such as uplink data or Uplink control signaling, DMRS can be used to demodulate uplink data or uplink control signaling. If there is no uplink data or uplink control signaling to be sent, no DMRS will be sent.

除了DMRS，在实际应用中，还存在另一种参考信号，即探测参考信号(SRS，Sounding Reference Signal)，用于实现Sounding功能。具体来说，在频分双工(FDD，Frequency Division Duplex)系统中，基站可利用SRS得到上行信道状况，从而进行上行频率的选择性调度和确定上行传输块的多速率编码方案(MCS，Multi-Code Scheme)；在时分双工(TDD，Time DivisionDuplex)系统中，SRS除了具备上述功能外，基站还可利用SRS以及上下行信道的互易性得到下行信道状况，进而根据下行信道状况进行下行发送前处理。在FDD系统中，SRS只能在每个子帧的最后一个符号进行发送，具体在哪个子帧进行发送由系统高层信令来配置，在TDD系统中，SRS除了可在每个子帧的最后一个符号进行发送外，还可在上行特殊时隙(UpPTS)进行发送。In addition to DMRS, in practical applications, there is another reference signal, namely Sounding Reference Signal (SRS, Sounding Reference Signal), which is used to implement the Sounding function. Specifically, in a frequency division duplex (FDD, Frequency Division Duplex) system, the base station can use the SRS to obtain the uplink channel conditions, thereby performing selective scheduling of uplink frequencies and determining the multi-rate coding scheme (MCS, Multi-rate coding scheme) of uplink transmission blocks. -Code Scheme); In a Time Division Duplex (TDD, Time DivisionDuplex) system, in addition to the above-mentioned functions of the SRS, the base station can also use the SRS and the reciprocity of the uplink and downlink channels to obtain the downlink channel status, and then perform downlink according to the downlink channel status Processing before sending. In the FDD system, SRS can only be sent at the last symbol of each subframe. The specific subframe to be sent is configured by the system high-level signaling. In the TDD system, SRS can only be sent at the last symbol of each subframe. In addition to sending, it can also be sent in an uplink special time slot (UpPTS).

可见，无论是对于FDD系统还是TDD系统，SRS均具有重要的作用，但由于SRS的发送限制，在某些情况下，可能会出现基站需要行使Sounding功能，却无SRS可用的问题，即SRS资源受限的问题，从而导致系统性能下降。针对这一问题，现有技术中还没有一种有效的解决方式。It can be seen that SRS plays an important role in both FDD and TDD systems. However, due to the limitation of SRS transmission, in some cases, there may be a problem that the base station needs to perform the Sounding function, but no SRS is available, that is, SRS resources Restricted issues, resulting in reduced system performance. For this problem, there is no effective solution in the prior art.

发明内容Contents of the invention

有鉴于此，本发明的主要目的在于提供一种上行参考信号处理方法，能够提升系统性能。In view of this, the main purpose of the present invention is to provide a method for processing an uplink reference signal, which can improve system performance.

本发明的另一目的在于提供一种基站，能够提升系统性能。Another object of the present invention is to provide a base station capable of improving system performance.

本发明的又一目的在于提供一种终端，能够提升系统性能。Another object of the present invention is to provide a terminal capable of improving system performance.

为达到上述目的，本发明的技术方案是这样实现的：In order to achieve the above object, technical solution of the present invention is achieved in that way:

一种上行参考信号处理方法，该方法包括：A method for processing an uplink reference signal, the method comprising:

A、基站接收来自终端的解调参考信号DMRS，利用所述DMRS代替探测参考信号SRS行使探测Sounding功能。A. The base station receives the demodulation reference signal DMRS from the terminal, and uses the DMRS to replace the sounding reference signal SRS to perform sounding function.

一种基站，包括：A base station, comprising:

第一接收单元，用于接收来自终端的解调参考信号DMRS；a first receiving unit, configured to receive a demodulation reference signal DMRS from a terminal;

处理单元，用于利用所述DMRS代替探测参考信号SRS行使探测Sounding功能。The processing unit is configured to use the DMRS to replace the sounding reference signal SRS to perform sounding function.

一种终端，包括：A terminal comprising:

第二接收单元，用于接收来自基站的上行授权UL grant信令；The second receiving unit is used to receive the uplink authorization UL grant signaling from the base station;

第二发送单元，用于根据所述UL grant信令确定是否需要向基站发送上行数据，如果是，则向基站发送解调参考信号DMRS和上行数据，否则，仅向基站发送DMRS。The second sending unit is used to determine whether to send uplink data to the base station according to the UL grant signaling, if yes, send the demodulation reference signal DMRS and uplink data to the base station, otherwise, only send the DMRS to the base station.

可见，采用本发明的技术方案，利用DMRS来代替SRS行使Sounding功能，从而在一定程度上解决了SRS资源受限的问题，提升了系统性能。It can be seen that by adopting the technical solution of the present invention, the DMRS is used to replace the SRS to perform the Sounding function, thereby solving the problem of limited SRS resources to a certain extent and improving system performance.

附图说明Description of drawings

图1为本发明方法实施例的流程图。Fig. 1 is a flowchart of a method embodiment of the present invention.

图2为本发明基站实施例的组成结构示意图。FIG. 2 is a schematic diagram of the composition and structure of the base station embodiment of the present invention.

图3为本发明终端实施例的组成结构示意图。FIG. 3 is a schematic diagram of the composition and structure of the terminal embodiment of the present invention.

具体实施方式Detailed ways

针对现有技术中存在的问题，本发明中提出一种全新的上行参考信号处理方案，即基站接收来自终端的DMRS，利用DMRS代替SRS行使Sounding功能，从而在一定程度上解决了SRS资源受限的问题，提升了系统性能。Aiming at the problems existing in the prior art, the present invention proposes a brand-new uplink reference signal processing scheme, that is, the base station receives the DMRS from the terminal, and uses the DMRS to replace the SRS to perform the Sounding function, thereby solving the limited SRS resource to a certain extent problems and improve system performance.

但是，这样处理也会存在一个问题：依据之前的介绍可知，只有在终端有上行数据或上行控制信令需要发送时，终端才会向基站发送DMRS，否则，则不会发送DMRS，那么，在终端没有上行数据或上行控制信令需要发送的情况下，如果基站需要行使Sounding功能，则同样会存在资源受限的问题。However, there is also a problem with this processing: According to the previous introduction, only when the terminal has uplink data or uplink control signaling to send, the terminal will send DMRS to the base station, otherwise, it will not send DMRS, then, in When the terminal has no uplink data or uplink control signaling to send, if the base station needs to perform the Sounding function, there will also be a problem of resource limitation.

针对这一问题，本发明所述方案中提出以下解决方式：For this problem, propose following solution in the scheme of the present invention:

现有技术中，当终端有上行数据需要发送时，终端会通知基站，如向基站发送上行请求；基站接收到上行请求后，会向终端返回上行授权(UL grant)信令；终端接收到UL grant信令(其中携带有发送所用资源和发送格式等信息)后，向基站发送DMRS和上行数据。当终端有上行控制信令需要发送时，如确定(ACK)、否定(NACK)信息，通常不需要通知基站，直接发送即可，相应地，基站也无需向终端返回UL grant信令。本发明所述方案中，在终端没有上行数据需要发送，但基站需要DMRS来行使Sounding功能时(即基站需要行使Sounding功能，但无SRS和DMRS可用)，基站也可向终端发送UL grant信令。那么对于终端来说，其在接收到UL grant信令后，则需要首先判断该UL grant信令是因为基站知道终端有上行数据需要发送而发送的UL grant信令，还是因为终端没有上行数据需要发送，但基站需要DMRS来行使Sounding功能而发送的UL grant信令，如果是前一种情况，则按照现有方式进行处理，即终端向基站发送DMRS和上行数据，如果是后一种情况，则从节省上行资源和终端功率以及降低干扰的角度出发，仅向基站发送DMRS。In the prior art, when the terminal has uplink data to send, the terminal will notify the base station, such as sending an uplink request to the base station; after receiving the uplink request, the base station will return an uplink grant (UL grant) signaling to the terminal; After the grant signaling (which carries information such as the resources used for sending and the sending format), the DMRS and uplink data are sent to the base station. When the terminal has uplink control signaling to send, such as acknowledgment (ACK) and negative (NACK) information, it usually does not need to notify the base station, and can be sent directly. Correspondingly, the base station does not need to return UL grant signaling to the terminal. In the scheme of the present invention, when the terminal has no uplink data to send, but the base station needs DMRS to perform the Sounding function (that is, the base station needs to perform the Sounding function, but no SRS and DMRS are available), the base station can also send UL grant signaling to the terminal . Then, for the terminal, after receiving the UL grant signaling, it needs to first judge whether the UL grant signaling is sent because the base station knows that the terminal has uplink data to send, or because the terminal has no uplink data to send. Send, but the base station needs DMRS to exercise the UL grant signaling sent by the Sounding function. If it is the former case, it will be processed according to the existing method, that is, the terminal sends DMRS and uplink data to the base station. If it is the latter case, From the perspective of saving uplink resources and terminal power and reducing interference, only the DMRS is sent to the base station.

为使本发明的技术方案更加清楚、明白，以下参照附图并举实施例，对本发明所述方案作进一步地详细说明。In order to make the technical solution of the present invention clearer and clearer, the solution of the present invention will be further described in detail below with reference to the accompanying drawings and examples.

图1为本发明方法实施例的流程图。如图1所示，包括以下步骤：Fig. 1 is a flowchart of a method embodiment of the present invention. As shown in Figure 1, the following steps are included:

步骤11：当终端有上行数据需要发送，以及当终端没有上行数据需要发送，但基站需要DMRS来行使Sounding功能时，基站向终端发送UL grant信令。Step 11: When the terminal has uplink data to send, and when the terminal has no uplink data to send, but the base station needs DMRS to perform the Sounding function, the base station sends UL grant signaling to the terminal.

步骤12：终端根据接收到的UL grant信令确定是否需要向基站发送上行数据，如果是，则向基站发送DMRS以及上行数据，否则，仅向基站发送DMRS。Step 12: The terminal determines whether it needs to send uplink data to the base station according to the received UL grant signaling, if yes, then sends DMRS and uplink data to the base station, otherwise, only sends DMRS to the base station.

本步骤的具体实现可采用以下两种方式：The specific realization of this step can adopt the following two ways:

1)终端确定自身缓存中是否存在待发送的上行数据且已通知基站该上行数据需要发送，如果是，则向基站发送DMRS和上行数据，否则，仅向基站发送DMRS。1) The terminal determines whether there is uplink data to be sent in its cache and has notified the base station that the uplink data needs to be sent, if yes, then sends DMRS and uplink data to the base station, otherwise, only sends DMRS to the base station.

该方式中，终端首先确定自身的缓存中是否存在待发送的上行数据，如果存在，则可初步认为接收到的UL grant信令为基站指示终端发送上行数据的UL grant信令，但还不能确定，因为在实际应用中可能存在这样一种情况，即终端自身的缓存中存在待发送的上行数据，但终端还没来得及向基站发送上行请求就接收到了来自基站的UL grant信令，那么显然，该UL grant信令为基站指示终端仅发送DMRS的UL grant信令，如果终端在接收到该ULgrant信令后向基站发送DMRS和上行数据，则违背了基站的意图。因此，终端在确定出自身的缓存中存在待发送的上行数据之后，还需要进一步确定出是否已针对该上行数据向基站发送了上行请求，如果是，则认为接收到的UL grant信令为基站指示终端发送上行数据的UL grant信令，向基站发送DMRS和上行数据，否则，仅向基站发送DMRS。In this method, the terminal first determines whether there is uplink data to be sent in its cache, and if so, it can be preliminarily considered that the received UL grant signaling is the UL grant signaling for the base station to instruct the terminal to send uplink data, but it cannot be determined yet , because there may be such a situation in practical applications, that is, there is uplink data to be sent in the terminal's own cache, but the terminal receives the UL grant signaling from the base station before sending an uplink request to the base station, then obviously, The UL grant signaling is the UL grant signaling for the base station to instruct the terminal to only send DMRS. If the terminal sends DMRS and uplink data to the base station after receiving the UL grant signaling, it violates the intention of the base station. Therefore, after determining that there is uplink data to be sent in its own cache, the terminal needs to further determine whether an uplink request has been sent to the base station for the uplink data, and if so, it considers that the received UL grant signaling is the base station's request. Instruct the terminal to send the UL grant signaling of uplink data, and send DMRS and uplink data to the base station, otherwise, only send DMRS to the base station.

2)终端确定接收到的UL grant信令的格式为基站指示终端发送上行数据的格式还是基站指示终端仅发送DMRS的格式；如果是基站指示终端发送上行数据的格式，则向基站发送DMRS和上行数据，如果是基站指示终端仅发送DMRS的格式，则仅向基站发送DMRS。2) The terminal determines whether the format of the received UL grant signaling is the format in which the base station instructs the terminal to send uplink data or the format in which the base station instructs the terminal to only send DMRS; if it is the format in which the base station instructs the terminal to send uplink data, then send DMRS and uplink For data, if the base station instructs the terminal to only send DMRS, then only DMRS is sent to the base station.

该方式中，针对两种不同的情况，基站可将发送的UL grant信令的格式设置得不同(如何设置不作限制，只要终端能够识别即可，比如可在UL grant信令中设置一指示位，通过将该指示位设置为不同的取值来表示两种不同的情况)，这样，终端只需依据接收到的UL grant信令的格式即可知道基站的意图。In this method, for two different situations, the base station can set the format of the UL grant signaling to be sent differently (there is no limit on how to set it, as long as the terminal can recognize it, for example, an indicator bit can be set in the UL grant signaling , to indicate two different situations by setting the indicator bit to different values), in this way, the terminal only needs to know the intention of the base station according to the format of the received UL grant signaling.

需要说明的是，上述两种方式仅为举例说明，在实际应用中，如果采用其它的方式，只要能够达到和上述两种方式同样的目的，也是可以的。It should be noted that the above two methods are only examples, and in practical applications, if other methods are used, as long as the same purpose as the above two methods can be achieved, it is also possible.

步骤13：基站接收来自终端的DMRS，利用DMRS代替SRS行使Sounding功能。Step 13: The base station receives the DMRS from the terminal, and uses the DMRS instead of the SRS to perform the Sounding function.

结合之前的介绍可知，本步骤中，基站接收到的可能仅为DMRS，也可能为DMRS和上行数据，对于后一种情况，基站既可利用DMRS来行使现有解调功能，又可在需要时利用其代替SRS来行使Sounding功能。Based on the previous introduction, it can be seen that in this step, the base station may receive only DMRS, or DMRS and uplink data. In the latter case, the base station can use DMRS to perform existing demodulation functions. When using it instead of SRS to exercise the Sounding function.

DMRS和SRS都是终端在特定的资源上发送的序列，其本质是一样的，为基站已知，基站通过接收已知的序列来进行信道估计，得到特定资源上的信道信息，进而行使Sounding功能。具体如何实现为本领域公知，不再赘述。Both DMRS and SRS are sequences sent by the terminal on a specific resource. They are essentially the same and known to the base station. The base station performs channel estimation by receiving the known sequence, obtains channel information on a specific resource, and then performs the Sounding function. . How to implement it is well known in the art and will not be repeated here.

基于上述介绍，图2为本发明基站实施例的组成结构示意图。如图2所示，包括：Based on the above introduction, FIG. 2 is a schematic diagram of a structure of a base station embodiment of the present invention. As shown in Figure 2, including:

第一接收单元21，用于接收来自终端的DMRS；Thefirst receiving unit 21 is configured to receive the DMRS from the terminal;

处理单元22，用于利用DMRS代替SRS行使Sounding功能。Theprocessing unit 22 is configured to use the DMRS instead of the SRS to perform the Sounding function.

图2所示基站中还可进一步包括：The base station shown in Figure 2 may further include:

第一发送单元23，用于当终端有上行数据需要发送，以及当终端没有上行数据需要发送，但基站需要DMRS来行使Sounding功能时，向终端发送UL grant信令；The first sendingunit 23 is used to send UL grant signaling to the terminal when the terminal has uplink data to send, and when the terminal has no uplink data to send, but the base station needs DMRS to exercise the Sounding function;

第一接收单元21接收来自终端的DMRS或DMRS和上行数据。Thefirst receiving unit 21 receives DMRS or DMRS and uplink data from a terminal.

图3为本发明终端实施例的组成结构示意图。如图3所示，包括：FIG. 3 is a schematic diagram of the composition and structure of the terminal embodiment of the present invention. As shown in Figure 3, including:

第二接收单元31，用于接收来自基站的UL grant信令；Thesecond receiving unit 31 is configured to receive UL grant signaling from the base station;

第二发送单元32，用于根据UL grant信令确定是否需要向基站发送上行数据，如果是，则向基站发送DMRS和上行数据，否则，仅向基站发送DMRS。Thesecond sending unit 32 is used to determine whether the uplink data needs to be sent to the base station according to the UL grant signaling, if yes, then send the DMRS and the uplink data to the base station, otherwise, only send the DMRS to the base station.

其中，第二发送单元32中可具体包括(为简化附图，未图示)：Wherein, the second sendingunit 32 may specifically include (to simplify the drawings, not shown):

确定子单元，用于确定自身的缓存中是否存在待发送的上行数据且已通知基站该上行数据需要发送，如果是，则通知发送子单元向基站发送DMRS和上行数据，否则，通知发送子单元仅向基站发送DMRS；The determining subunit is used to determine whether there is uplink data to be sent in its own cache and the base station has been notified that the uplink data needs to be sent, if yes, notify the sending subunit to send DMRS and uplink data to the base station, otherwise, notify the sending subunit Only send DMRS to the base station;

发送子单元，用于根据接收自确定子单元的通知消息执行相应的操作。The sending subunit is configured to perform corresponding operations according to the notification message received from the determining subunit.

或者，or,

确定子单元，用于确定所述UL grant信令的格式为基站指示终端发送上行数据的格式还是基站指示终端仅发送DMRS的格式；如果是基站指示终端发送上行数据的格式，则通知发送子单元向基站发送DMRS和上行数据，如果是基站指示终端仅发送DMRS的格式，则通知发送子单元仅向基站发送DMRS；The determination subunit is used to determine whether the format of the UL grant signaling is the format in which the base station instructs the terminal to send uplink data or the format in which the base station instructs the terminal to only send DMRS; if it is the format in which the base station instructs the terminal to send uplink data, then notify the sending subunit Send DMRS and uplink data to the base station, if the base station instructs the terminal to only send DMRS format, notify the sending subunit to only send DMRS to the base station;

发送子单元，用于根据接收自确定子单元的通知消息执行相应的操作。The sending subunit is configured to perform corresponding operations according to the notification message received from the determining subunit.

图2和3所示装置实施例的具体工作流程请参照图1所示方法实施例中的相应说明，此处不再赘述。For the specific working process of the device embodiment shown in FIGS. 2 and 3 , please refer to the corresponding description in the method embodiment shown in FIG. 1 , which will not be repeated here.

总之，采用本发明的技术方案，可解决SRS资源受限问题，从而提升系统性能。In a word, adopting the technical solution of the present invention can solve the problem of limited SRS resources, thereby improving system performance.

以上所述仅为本发明的较佳实施例而已，并不用以限制本发明，凡在本发明的精神和原则之内，所做的任何修改、等同替换、改进等，均应包含在本发明保护的范围之内。The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the present invention. within the scope of protection.

Claims (9)

1. An uplink reference signal processing method, comprising:

A. the base station receives a demodulation reference signal (DMRS) from the terminal, and the DMRS is used for replacing a Sounding Reference Signal (SRS) to perform Sounding function.

2. The method of claim 1, wherein step a is preceded by the further step of:

x1, when the terminal has uplink data to send, and when the terminal does not have uplink data to send but the base station needs DMRS to play Sounding function, the base station sends uplink grant (UL grant) signaling to the terminal;

and the X2 and the terminal determine whether uplink data needs to be sent to the base station after receiving the UL grant signaling, if so, the terminal sends the DMRS and the uplink data to the base station, otherwise, only sends the DMRS to the base station.

3. The method according to claim 2, wherein the step X2 comprises:

the terminal determines whether uplink data to be sent exists in a buffer memory of the terminal and informs the base station that the uplink data needs to be sent, if so, the terminal sends the DMRS and the uplink data to the base station, otherwise, only the base station sends the DMRS.

4. The method according to claim 2, wherein the step X2 comprises:

the terminal determines whether the format of the UL grant signaling is a format in which the base station indicates the terminal to send uplink data or a format in which the base station indicates the terminal to send only the DMRS;

and if the base station indicates that the terminal only transmits the DMRS format, only transmitting the DMRS format to the base station.

5. A base station, comprising:

a first receiving unit, configured to receive a demodulation reference signal DMRS from a terminal;

and the processing unit is used for replacing the Sounding Reference Signal (SRS) with the DMRS to perform a Sounding function.

6. The base station of claim 5, further comprising:

the base station comprises a first sending unit, a second sending unit and a sending unit, wherein the first sending unit is used for sending a UL grant signaling to the terminal when the terminal has uplink data to send and when the terminal does not have the uplink data to send but the base station needs the DMRS to perform a Sounding function;

the first receiving unit receives the DMRS or the DMRS and uplink data from the terminal.

7. A terminal, comprising:

a second receiving unit, configured to receive an uplink grant (UL grant) signaling from a base station;

and the second sending unit is used for determining whether uplink data needs to be sent to the base station according to the UL grant signaling, if so, sending a demodulation reference signal (DMRS) and the uplink data to the base station, and otherwise, only sending the DMRS to the base station.

8. The terminal of claim 7, wherein the second sending unit comprises:

the device comprises a determining subunit, a sending subunit and a receiving subunit, wherein the determining subunit is used for determining whether uplink data to be sent exists in a buffer memory of the sending subunit and informing a base station that the uplink data need to be sent, if so, the sending subunit is informed to send the DMRS and the uplink data to the base station, otherwise, the sending subunit is informed to only send the DMRS to the base station;

and the sending subunit is used for executing corresponding operation according to the notification message received from the determining subunit.

9. The terminal of claim 7, wherein the second sending unit comprises:

a determining subunit, configured to determine whether a format of the UL grant signaling is a format in which the base station instructs the terminal to transmit uplink data or a format in which the base station instructs the terminal to transmit only the DMRS; if the base station indicates that the terminal transmits the format of the uplink data, the transmitting subunit is informed to transmit the DMRS and the uplink data to the base station, and if the base station indicates that the terminal transmits only the format of the DMRS, the transmitting subunit is informed to transmit only the DMRS to the base station;

and the sending subunit is used for executing corresponding operation according to the notification message received from the determining subunit.

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