WO2011090293A2 - Apparatus and method for providing emergency service in a broadband mobile communication system - Google Patents

Abstract

The present description relates to a method for providing an emergency service for a terminal in a broadband mobile communication system, wherein the method involves receiving an emergency service message for the terminal in an idle mode having a paging cycle consisting of a paging available interval and a paging unavailable interval, and comprises the following processes: receiving a control message including information which indicates that the emergency service message was transmitted in the paging available interval, and information which indicates the point in time the emergency service message was transmitted; if it is verified, from the received control message, that the point in time the emergency service message was transmitted is after the paging available interval, maintaining the idle mode until the emergency service message is received; receiving a first message including a system parameter in the paging unavailable interval, and comparing whether the point in time the first message was received and the point in time the emergency service message was transmitted correspond with each other; and, if the points in time correspond with each other, shifting to a wakeup state from the point in time the first message was received, and receiving the emergency service message.

Description

Apparatus and method for providing emergency service information in broadband mobile communication system

The present disclosure relates to a method in which an idle or sleep mode terminal receives an emergency alert message while maintaining an idle or sleep state.

Next-generation communication systems are evolving in the form of providing a variety of high-speed, high-capacity services to mobile stations (MSs). Representative examples of next-generation communication systems include the Institute of Electrical and Electronics Engineers (IEEE) 802.16 communication system and the Mobile Interoperability for Microwave Access (WiMAX) communication system. Here, the Mobile WiMAX communication system is a communication system based on the IEEE 802.16 communication system, and the IEEE 802.16 communication system represents a communication system using the IEEE 802.16 standard.

 Now, the emergency service proposed by the IEEE 802.16 communication system will be described.

 In general, emergency services include Wireless Emergency Rescue Service (WERS) and Wireless Emergency Alert Service (WEAS). The following description will be given of each of the WERS and WEAS.

 First, the WERS may also be referred to as MS-triggered Emergency Service (hereinafter referred to as MS-triggered ES). Includes services that support the secure structure by identifying the location of the MS when it occurs. In the case of the WERS, since it is generally triggered by the MS, it is called MS-triggered ES. The WERS includes a voice call service such as a 911 service.

 Secondly, the WEAS may be referred to as a base station (BS) triggered emergency service (BS-triggered ES) hereinafter, and may be referred to an MS existing at a specific geographical location. Storm

And services that support emergency notifications such as earthquake and tsunami notices. In the case of the WEAS, it is generally called BS-triggered ES because it is triggered by a base station.

 In the related art, when the idle or sleep mode terminal receives an emergency alert indication from the base station, the listening mode is maintained until the emergency alert message is received. That is, the terminal operating in the idle mode does not enter the paging unavailable interval until the emergency alert message is received, and the terminal operating in the sleep mode does not enter the sleep interval. Therefore, there is a problem that the power saving effect is reduced.

Therefore, the present specification describes a method for receiving an emergency alert message transmitted by a base station while maintaining an idle or sleep state in order to maximize power saving of the terminal.

An object of the present specification is to provide a method and apparatus for providing emergency service information through a control message including information on whether emergency service information is transmitted and information on transmission time.

The present specification provides a method for providing an emergency service of a terminal in a broadband wireless communication system, in an idle mode having a paging cycle including a paging available interval and a paging unavailable interval. A method for receiving an emergency service message of a terminal, the method comprising: receiving a control message including information indicating that an emergency service message is transmitted and information indicating when to send an emergency service message in the paging segment; Maintaining an idle mode until the emergency service message is received when the emergency service message transmission time is after the paging segment; In the non-paging period, after receiving a first message including a system parameter, comparing the first message reception time point with the emergency service message transmission time point; And if the result of the comparison is identical, transitioning to the wake-up state at the time of receiving the first message and receiving the emergency service message.

The method may further include operating in an idle mode state before the wake-up after the emergency service message is received.

In addition, the first message may be a first super-frame header (P-SFH).

The information indicating the time point at which the emergency service message is transmitted is information indicating a super frame position at which the emergency service message is transmitted, and the super frame position is determined according to a value set in a LSB (Least Significant Bit) of the super frame number. It features.

The system parameter may include an LSB of a super frame number to which the first message is transmitted, and the comparing may include setting an LSB of the super frame number included in the system parameter and an LSB indicating a time point for transmitting the emergency service message. And comparing the values.

The control message may be a paging advertisement message (AAI_PAG-ADV message).

In addition, the location where the emergency service message is transmitted is characterized in that the sub-frame or frame in which the first message is transmitted.

In the present specification, in the method for receiving an emergency service message of the terminal in a sleep mode having a sleep cycle consisting of a listening window (Listening window) and a sleep window (Sleep window), the listening section Receiving a control message including information indicating that an emergency service message is transmitted and information indicating when to send an emergency service message; Maintaining a sleep mode state until the emergency service message is received when the emergency service message transmission time is after the listening period as a result of checking the received control message; In the sleep period, after receiving a first message including a system parameter, comparing the first message reception time point with the emergency service message transmission time point; And if it is determined that the comparison results in a match, transitioning to the wake-up state at the time of receiving the first message and receiving the emergency service message.

The control message may be a data traffic generation indication message or a sleep control extended header.

Also, in the present specification, in the terminal for receiving an emergency service message in an idle mode having a paging cycle consisting of a paging available interval and a paging unavailable interval, A receiving unit for receiving a control message including information indicating that an emergency service message is transmitted in a paging segment and information indicating when to send an emergency service message, and receiving an emergency service message in the non-paging segment; A message interpreter for detecting, from the received control message, a reception time of a first message including a system parameter in a transmission time and a non-paged period of the emergency service message; And a controller for determining whether the emergency service message transmission time is after a paging segment and controlling the operation of the terminal.

The controller may compare the time point at which the emergency service message is transmitted with the time point at which the first message is received, and then control to transition to the wake-up state when the comparison result is matched.

In the present specification, when an emergency service message is transmitted, information about a time point of transmitting an emergency service message is transmitted in advance, so that power consumption of a terminal operating in a sleep mode or an idle mode can be reduced.

1 is a diagram illustrating a procedure for receiving an emergency alert message in a terminal according to the first embodiment of the present disclosure.

2 is a diagram illustrating a method for transmitting an emergency alert message to a terminal by a base station according to the first embodiment of the present disclosure.

3 is a diagram illustrating a procedure for receiving an emergency alert message in a terminal according to a second embodiment of the present disclosure.

4 is a diagram illustrating a procedure for receiving an emergency alert message in a terminal according to a third embodiment of the present disclosure.

5 is a diagram for receiving emergency alert information according to an embodiment of the present disclosure.

Inner block diagram of horse.

Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It should be noted that in the following description, only parts necessary for understanding the operation according to the present specification will be described, and descriptions of other parts will be omitted so as not to distract from the gist of the present specification.

The present specification proposes an apparatus and method for providing an emergency service in a communication system, for example, a communication system using the Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard (hereinafter referred to as an IEEE 802.16 communication system).

In the present specification, an apparatus and method for providing an emergency service using the IEEE 802.16 communication system as an example will be described. However, the apparatus and method for providing an emergency service may be applied to other communication systems as well as the IEEE 802.16 communication system. Of course.

The following embodiments are the components and features of the present specification are combined in a predetermined form. Each component or feature is to be considered optional unless stated otherwise. Each component or feature may be embodied in a form that is not combined with other components or features. In addition, it is also possible to configure the embodiments of the present disclosure by combining some components and / or features. The order of the operations described in the embodiments herein may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment.

Embodiments in the present specification have been described with reference to the data transmission and reception relationship between the base station and the terminal. Here, the base station has a meaning as a terminal node of the network that directly communicates with the terminal. The specific operation described as performed by the base station in this document may be performed by an upper node of the base station in some cases.

That is, it is obvious that various operations performed for communication with a terminal in a network composed of a plurality of network nodes including a base station may be performed by the base station or other network nodes other than the base station. 'Base station' may be replaced by terms such as a fixed station, a Node B, an eNode B (eNB), an access point, and the like. In addition, the term "terminal" may be replaced with terms such as a user equipment (UE), a mobile station (MS), a mobile subscriber station (MSS), and the like.

Embodiments of the present specification may be implemented through various means. For example, embodiments of the present specification may be implemented by hardware, firmware, software, or a combination thereof.

In the case of a hardware implementation, a method according to embodiments of the present disclosure may include one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs). Field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, and the like.

In the case of an implementation by firmware or software, the method according to the embodiments of the present specification may be implemented in the form of a module, procedure or function that performs the functions or operations described above. The software code may be stored in a memory unit and driven by a processor. The memory unit may be located inside or outside the processor, and may exchange data with the processor by various known means.

Specific terms used in the following description are provided to help the understanding of the present specification, and the use of the specific terms may be changed into other forms without departing from the technical spirit of the present specification.

First embodiment

A first embodiment of the present disclosure provides a method for receiving an emergency service message, in particular an emergency alert message, while maintaining an idle mode state in an idle mode terminal.

1 is a diagram illustrating a procedure for receiving an emergency alert message in a terminal according to the first embodiment of the present disclosure.

First, the terminal receives a control message including information indicating whether an emergency alert message is transmitted in a paging segment (S110). When the information indicates that an emergency alert message is transmitted, the control message indicates a time point at which an emergency alert message is transmitted. It will contain more information.

The information indicating the time point at which the emergency alert message is transmitted informs the location of the superframe in which the emergency alert message is transmitted. The location of the super frame is represented using a LSB (Least Significant) or LSB and Most Significant Bit (MSB) of the super frame number. That is, the emergency alert message is transmitted in the super frame corresponding to the LSB or the bit values set in the LSB and the MSB.

For example, when the information indicating the time of the emergency alert message transmission indicates that 4 bits of the LSB of the super frame number is set to '0', the location of the super frame through which the emergency alert message is transmitted is 4 of the LSB of the super frame number. Corresponds to the super frame where the bit is set to '0'. In addition, when the 3 bits of the LSB of the super frame number is set to '0', the position of the super frame in which the emergency alert message is transmitted corresponds to the super frame in which the 3 bits of the LSB of the super frame number are set to '0'. do.

Here, the location of the super frame may be informed by using both the LSB and the MSB according to the transmission time of the emergency alert message.

The terminal transmits a LSB (Least Significant Bit) or LSB and Most Significant Bit (LSB) of a super frame number included in a first super-frame header (P-SFH) transmitted every superframe. By checking, the transmitted super frame number can be known. That is, the base station informs the location of the super frame in which the emergency alert message is transmitted using the LSB or the LSB and the MSB of the super frame number.

For example, the base station determines the transmission interval of the emergency alert message as a period in which 4 bits of the LSB of the super frame number is set to '0' and transmits it to the terminal. In this case, the emergency alert message is transmitted for each section in which 4 bits of the LSB of the super frame number are set to '0'. That is, the terminal can know the super frame number through which the emergency alert message is transmitted through a control message transmitted from the base station.

Here, the control message may be a paging advertisement message (AAI_PAG-ADV message).

Next, as a result of checking the received control message, when the emergency service message transmission time is after the paging segment, the idle mode state is maintained until the emergency service message is received. Here, whether the time of the emergency alert message transmission is after the paging segment may be determined by comparing information about the time of emergency alert message transmission with the LSB of the super frame number included in the super frame header received in the paging segment.

Accordingly, even if the terminal receives information indicating that an emergency alert message is transmitted among the paging segments, the terminal maintains a listening state only during the paging segment, and the idle mode after the paging segment ends. Will be maintained.

Next, a first message including a system parameter transmitted in the non-paged period is received (S120). The first message may be a super frame header (SFH). The first message is transmitted every super frame, and includes information indicating a super frame number to which the first message is transmitted. That is, the position of the super frame can be known through the LSB of the super frame number included in the first message.

That is, the terminal receives the basic information of the system through the first message even in the non-paged period. The system parameter includes LSB information of the super frame number.

Next, after receiving the first message, it is compared whether the position of the super frame in which the first message is transmitted coincides with the position of the super frame in which the emergency alert message is transmitted. As a result of the comparison, if there is a mismatch, the idle mode state is maintained.

However, when the first message is received as a result of the comparison, when the emergency alert message is transmitted, that is, when the LSB of the super frame number is matched, the current idle mode state is transitioned to the wake-up state at the time of receiving the first message. do.

Next, the terminal receives an emergency alert message transmitted from the base station in the state of transition to the wake-up state (S130). Here, the time point at which the emergency alert message is transmitted is a frame or subframe in which the first message is transmitted. Can be.

Next, after receiving the emergency alert message in the non-paged interval, the transition to the state before the wake-up, that is, the idle mode.

Here, the terminal receives the emergency alert message in a state of wake-up in the super frame in which the emergency alert message is transmitted, and after the super frame passes, the terminal transitions back to the idle mode state before the wake-up.

2 is a diagram illustrating a method for transmitting an emergency alert message to a terminal by a base station according to the first embodiment of the present disclosure.

First, the base station transmits a control message including information indicating whether to send an emergency alert message to the terminal. The control message may be a paging advertisement message (AAI_PAG-ADV message).

Here, when an emergency alert message is generated, the base station sets bit values of the LSB or the LSB and the MSB of the super frame number in accordance with the period of transmitting the emergency alert message, that is, according to the time point of transmitting the emergency alert message.

For example, if the transmission period of the emergency alert message is 320ms, the LSB 4 bit of the super frame number is set to '0' to transmit the emergency alert message to the terminal in the corresponding super frame. Here, since one super frame is 20 ms, 320 ms corresponds to 16 super frames. Therefore, whenever the 4 bits of the LSB are set to '0', the transmission time of the emergency alert message can be determined. 4 bits of the LSB may be set to '1' instead of '0'. In this case, an emergency alert message is transmitted in a super frame in which 4 bits of the LSB are set to '1'.

As another example, when the base station transmits the emergency alert message to the terminal is 160ms, whenever the LSB 3 bits of the super frame is set to '0', the emergency alert message is transmitted to the terminal. That is, the LSB of the super frame is set according to the emergency alert message transmission period, and the emergency alert message is transmitted to the terminal in the corresponding super frame.

If the transmission period of the emergency alert message transmitted by the base station to the terminal exceeds 320ms, since the bits of the LSB of the super frame number of the P-SFH are 4 bits, the transmission interval of the emergency alert message is fixed only by the 4 bits. It is impossible. Therefore, when the period of transmitting the emergency alert message exceeds 320ms, the emergency alert message is transmitted using not only the LSB of the super frame number of the P-SFH but also the MSB bit of the super frame number of the S-SFH SP1 IE. Additional bits can be set to '0' to match the period.

Accordingly, when an emergency alert message is generated, information on the transmission time point of the emergency alert message along with information indicating that the emergency alert message is transmitted, that is, bits of LSBs or LSBs and MSBs of the set super frame number are included in the control message. Include and send.

Next, the base station transmits the P-SFH including the LSB of the corresponding super frame number to the terminal for every super frame in the non-paged period (S210).

Next, the base station transmits an emergency alert message at the location of the set super frame (S220).

Second embodiment

The second embodiment of the present disclosure provides another method of receiving an emergency service message, in particular an emergency alert message, while maintaining an idle mode state in an idle mode terminal.

3 is a diagram illustrating a procedure for receiving an emergency alert message in a terminal according to a second embodiment of the present disclosure.

First, the process of the terminal receiving a control message including information on the timing of the transmission of the emergency alert message in the paging interval, and the transition from the time of the emergency alert message transmission to the wake-up state in the non-paging interval operation of the terminal of the first embodiment Since it is the same as the description thereof will be omitted. (S310 ~ S330)

Next, the terminal receives the emergency alert message transmitted from the base station in the state transitioned to the wake-up state at the time of transmitting the emergency alert message. Here, the time point at which the emergency alert message is transmitted corresponds to a subframe or frame in which the first message is transmitted. That is, when the first message is a P-SFH, the time point at which the emergency alert message is transmitted corresponds to a subframe or frame in which the P-SFH is transmitted.

Next, after receiving the emergency alert message, the system transitions back to the state before the wakeup, that is, the idle mode. That is, the terminal wakes up in the corresponding super frame in which the emergency alert message is transmitted, receives the emergency alert message, and then transitions to the idle mode state without maintaining the wake up state during the super frame.

Third embodiment

A third embodiment of the present disclosure provides a method for receiving an emergency service message, especially an emergency alert message, while maintaining a sleep mode state in a terminal in a sleep mode.

4 is a diagram illustrating a procedure for receiving an emergency alert message in a terminal according to a third embodiment of the present disclosure.

First, the terminal receives a control message including information indicating whether to send an emergency alert message in a sleep interval (S410). If the information indicates that an emergency alert message is transmitted, the control message indicates a time point at which an emergency alert message is transmitted. It will contain more information.

The information indicating the time point at which the emergency alert message is transmitted informs the location of the superframe in which the emergency alert message is transmitted. The location of the super frame is represented using a LSB (Least Significant) or LSB and Most Significant Bit (MSB) of the super frame number. That is, the emergency alert message is transmitted in the super frame corresponding to the LSB or the bit values set in the LSB and the MSB.

For example, when the information indicating the time of the emergency alert message transmission indicates that 4 bits of the LSB of the super frame number is set to '0', the location of the super frame through which the emergency alert message is transmitted is 4 of the LSB of the super frame number. Corresponds to the super frame where the bit is set to '0'. In addition, when the 3 bits of the LSB of the super frame number is set to '0', the position of the super frame in which the emergency alert message is transmitted corresponds to the super frame in which the 3 bits of the LSB of the super frame number are set to '0'. do.

Here, the location of the super frame may be informed by using both the LSB and the MSB according to the transmission time of the emergency alert message.

The terminal transmits a LSB (Least Significant Bit) or LSB and Most Significant Bit (LSB) of a super frame number included in a first super-frame header (P-SFH) transmitted every superframe. By checking, the transmitted super frame number can be known. That is, the base station informs the location of the super frame in which the emergency alert message is transmitted using the LSB or the LSB and the MSB of the super frame number.

For example, the base station determines the transmission interval of the emergency alert message as a period in which 4 bits of the LSB of the super frame number is set to '0' and transmits it to the terminal. In this case, the emergency alert message is transmitted for each section in which 4 bits of the LSB of the super frame number are set to '0'. That is, the terminal can know the super frame number through which the emergency alert message is transmitted through a control message transmitted from the base station.

Herein, the control message may be a data traffic generation indication message (AAI_TRF-IND message) or a sleep mode extended header.

Next, as a result of checking the received control message, when the emergency service message transmission time is after the listening period, that is, during the sleep period, the sleep mode state is maintained until the emergency service message is received. Here, whether the time of the emergency alert message transmission is after the listening period may be determined by comparing the information on the time of emergency alert message transmission with the LSB of the super frame number included in the super frame header received in the listening period.

Accordingly, even if the terminal receives information indicating that an emergency alert message is transmitted among the paging segments, the terminal maintains a listening state only during the paging segment, and the idle mode after the paging segment ends. Will be maintained.

Next, a first message including a system parameter transmitted in the sleep period is received (S420). The first message may be a super frame header (SFH). The first message is transmitted every super frame, and includes information indicating a super frame number to which the first message is transmitted. That is, the position of the super frame can be known through the LSB of the super frame number included in the first message.

That is, the terminal receives the basic information of the system through the first message even in the sleep period. The system parameter includes LSB information of the super frame number.

Next, after receiving the first message, it is compared whether the position of the super frame in which the first message is transmitted coincides with the position of the super frame in which the emergency alert message is transmitted. As a result of the comparison, if it does not match, the sleep mode state is maintained.

However, as a result of the comparison, when the first message is received when the emergency alert message is transmitted, that is, when the LSB of the super frame number matches, the current sleep mode state is transitioned to the wake-up state at the first message reception time. do.

Next, the terminal receives the emergency alert message transmitted from the base station in the transition state to the wake-up state (S430). Here, the time point at which the emergency alert message is transmitted is a frame or subframe in which the first message is transmitted. Can be.

Next, after receiving the emergency alert message in the sleep interval, it transitions back to the state before the wake-up, that is, the sleep mode state.

Here, the terminal receives the emergency alert message in the state of wake-up in the super frame in which the emergency alert message is transmitted, and after the super frame passes, the terminal transitions back to the sleep mode state before the wake-up.

In addition, if the time point at which the emergency alert message is transmitted is a frame or subframe through which the first message is transmitted, the terminal may transition to the sleep mode after receiving the emergency alert message even during the corresponding superframe.

5 is a diagram illustrating an internal block diagram of a terminal for receiving emergency alert information according to an embodiment of the present specification.

The terminal 500 includes a receiver 510, a message analyzer 520, and a controller 530.

First, the receiving unit 510 receives a control message including information indicating that an emergency service message is transmitted in a paging segment and information indicating when to send an emergency service message, and receives an emergency service message in the non-paging segment.

The control message may be a paging advertisement message. The information indicating the time point at which the emergency service message is transmitted is information indicating a super frame position at which the emergency service message is transmitted, and the super frame position is determined according to a value set in a LSB (Least Significant Bit) of the super frame number.

The message analyzing unit 520 detects a time point of transmitting the emergency service message and a time point of receiving a first message including a system parameter in a non-paged period from the received control message. Here, the system parameter includes the LSB of the super frame number in which the first message is transmitted.

The controller 530 determines whether the emergency service message transmission time is after the paging segment and controls the operation of the terminal. In this case, when the transmission time point is after the paging segment, it is controlled to maintain the idle mode state of the current terminal until the emergency service message is received.

In addition, the controller compares whether an emergency service message transmission time coincides with a reception time of the first message and controls to transition to a wake-up state when the comparison result is matched.

In this case, the matching process may be set in the LSB of the super frame number included in the system parameter and in the LSB indicating the time point of transmitting the emergency service message.

Claims (11)

A method for receiving an emergency service message of a terminal in an idle mode having a paging cycle including a paging available interval and a paging unavailable interval, Receiving a control message including information indicating that an emergency service message is transmitted and information indicating when to send an emergency service message in the paging segment; Maintaining an idle mode until the emergency service message is received when the emergency service message transmission time is after the paging segment; In the non-paging period, after receiving a first message including a system parameter, comparing the first message reception time point with the emergency service message transmission time point; And And a result of the comparison, after the transition to the wake-up state at the time of receiving the first message, receiving the emergency service message. The method of claim 1, And after the receiving of the emergency service message, operating in the idle mode before the wake-up. The method of claim 1, The first message is a method of receiving an emergency service message, characterized in that the first super-frame header (P-SFH). The method of claim 1, The information indicating the time point at which the emergency service message is transmitted indicates the location of the super frame in which the emergency service message is transmitted, and the location of the super frame is determined according to a value set in the LSB of the super frame number. How to receive emergency service messages. The method of claim 4, wherein The system parameter may include an LSB of a super frame number in which the first message is transmitted, and the comparing may include a value set in the LSB of the super frame number included in the system parameter and an LSB indicating a time point for transmitting the emergency service message. Emergency service message receiving method characterized in that the matching. The method of claim 1, The control message is a paging advertisement message (AAI_PAG-ADV Message) characterized in that the emergency service message receiving method. The method of claim 2, The location where the emergency service message is transmitted is an emergency service message receiving method, characterized in that the sub-frame or frame in which the first message is transmitted. In the method for receiving an emergency service message of the terminal in a sleep mode having a sleep cycle consisting of a listening window (Listening window) and a sleep window (Sleep window), Receiving a control message including information indicating that an emergency service message is transmitted and information indicating when to send an emergency service message in the listening section; Maintaining a sleep mode state until the emergency service message is received when the emergency service message transmission time is after the listening period as a result of checking the received control message; In the sleep period, after receiving a first message including a system parameter, comparing the first message reception time point with the emergency service message transmission time point; And And a result of the comparison, after the transition to the wake-up state at the time of receiving the first message, receiving the emergency service message. The method of claim 8, The control message is a data traffic generation indication message or a method for receiving an emergency service message, characterized in that a sleep control extended header (sleep control extended header). A terminal for receiving an emergency service message in an idle mode having a paging cycle including a paging available interval and a paging unavailable interval, A receiver configured to receive a control message including information indicating that an emergency service message is transmitted in the paging segment and information indicating a time at which the emergency service message is transmitted, and receiving an emergency service message in the non-paging segment; A message interpreter for detecting, from the received control message, a reception time of a first message including a system parameter in a transmission time and a non-paged period of the emergency service message; And And a control unit for controlling the operation of the terminal by determining whether the time point for transmitting the emergency service message is after a paging segment. The method of claim 10, The control unit compares whether an emergency service message transmission time and the first message reception time coincide with each other, and controls to transition to a wake-up state when the comparison result is matched.

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