KR101669407B1 - the Mission Critical Push-To-Talk control method for packet data loss in mobile radio communication - Google Patents
the Mission Critical Push-To-Talk control method for packet data loss in mobile radio communication Download PDFInfo
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- KR101669407B1 KR101669407B1 KR1020150113262A KR20150113262A KR101669407B1 KR 101669407 B1 KR101669407 B1 KR 101669407B1 KR 1020150113262 A KR1020150113262 A KR 1020150113262A KR 20150113262 A KR20150113262 A KR 20150113262A KR 101669407 B1 KR101669407 B1 KR 101669407B1
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- H04W76/005—
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- H04W28/042—
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
- H04W4/06—Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
- H04W4/08—User group management
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
- H04W4/06—Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
- H04W4/10—Push-to-Talk [PTT] or Push-On-Call services
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Abstract
The present invention provides a group communication service such as Push-to-Talk (PTT), which is indispensable in a special-purpose mobile communication system based on LTE, in a wireless communication system environment where packet loss frequently occurs, The present invention relates to an MCPTT control method for packet loss in a wireless communication system in which an operation is enabled and a method thereof is divided into an On-network (FIG. 3) and an Off-network (FIG. 4) A method for controlling MCPTT for packet loss in a wireless communication system; In the case of the on-network, the MCPTT server 11 is composed of a plurality of receiving terminal groups such as the mobile terminal 1 to the mobile terminals 3, 21, 22 and 23. The MCPTT server 11 The mobile terminals 1 to 3 (21), (22) and (23) are wirelessly connected to the mobile communication network while being present in the mobile communication network; In the case of the off-network, the mobile terminal 12 serving as an MCPTT server and the plurality of receiving terminal groups such as the mobile terminal 1 to the mobile terminals 3, 21, 22 and 23, The mobile terminal 12 and the receiving terminals 21, 22, and 23 of the server role are connected through a direct communication method that does not pass the mobile communication network; In either of the On-network and the off-network, when one of the receiving terminals desires to obtain a floor, a floor request signal is transmitted to the MCPTT server or the terminal serving as the floor request signal; The MCPTT server 11 selects a receiving terminal to take the floor by way of a floor arbitration process, delivers a floor grant to the floor-right obtaining terminal, adds a maximum floor holding time Td to the floor grant message .
Description
The present invention relates to a MCPTT control method for packet loss in a wireless communication system, and more particularly, to a MCPTT control method for a group communication service such as Push-to-Talk (PTT) The present invention relates to a method of controlling an MCPTT for packet loss in a wireless communication system in which a normal operation can be performed even in packet loss in a wireless communication system environment where packet loss frequently occurs.
In recent years, there has been an increasing interest in special-purpose mobile communication systems such as disaster safety nets and railway network-specific integrated wireless networks, and most special purpose mobile communication systems are being built on the basis of LTE being used in commercial applications.
In such a special-purpose mobile communication system, it is necessary to provide a group communication service such as a push-to-talk (PTT) service, and this service should be able to be serviced in various environments such as a disaster situation.
In addition, 3GPP has standardized the name of this PTT service as Mission Critical Push-To-Talk (MCPTT), and defines not only coverage within mobile communication system coverage but also services outside coverage using direct communication between terminals , Discussing the technology.
In the PTT-type group call described above, only one person (i.e., one terminal) who has acquired the voice in the group needs to be able to speak at a moment. Therefore, algorithms and techniques for appropriately assigning voice are essential, If there is no coverage, it is usually necessary for the terminal in the group to perform the management of the voice rather than the server in the network.
Even in such a mobile communication system, a packet loss to be transmitted may sufficiently occur depending on a radio environment, and packet loss may occur more conspicuously in a direct communication environment.
Also, if the packet data related to the voice control is lost in the wireless transmission process, the terminal in the group may not receive the state (e.g., acquisition, retrieval, etc.) of the voice command, and the voice command algorithm may not operate normally at this time.
Further, there is a possibility that when the terminals are not shared with each other at the time of termination of the talk right, the talk right is maintained and the talk talk is not made.
Referring to FIG. 1, PTT over Cellular system, which is a standard established by the Open Mobile Alliance (OMA) as a Push-To-Talk system, is presently used most as the IP-based PTT system. Similarly, the talk control is performed based on the Media Burst Control Protocol.
A media burst granted message is sent to the terminal to which the floor is to be granted after the floor request, and the maximum speaking time can additionally be included in the message. At this time, the media burst taken message is sent to the other terminal, .
The terminal that has acquired the voice when the voice is revoked sends a Media Burst Release message to the server, and the server shares the revoked state information with the media burst idle message to the terminals in the group.
Referring to FIG. 2, the MCPTT in 3GPP is establishing the TS 23.179 standard. Here, the floor control is provided under the name of floor control, the floor request is requested through the floor request similar to the OMA PoC, and the floor grant / Announcement of the right to speak through floor release / released / idle.
An example of the prior art of the above-mentioned field will be described.
According to Korean Patent Publication No. 2006-8821 (PT Service System and Method for Improving User Service Quality), a PT service system and method for improving user service quality are disclosed. In the PT service system and method, A PTT client for applying a transmission time information of the lost floor request message to a floor request message for retransmitting the floor when the floor request message is lost; And a PTT server for transmitting a response message to the talk burst request message and assigning a higher announcement priority to the talk burst request message as the transmission time is longer. In addition to improving the service reliability even when the talk burst request message is lost, It is disclosed that the quality of the user service can be improved by giving the presentation order.
However, in both the OMA PoC and 3GPP MCPTT systems, there is a possibility that the receiving terminal can not receive the media burst idle message or the floor released message depending on the state of the wireless section. In this case, the terminal can not recognize the voice- It can be said that it is impossible to speak.
In the OMA PoC, there is a method of seeing whether each data packet reaches through T1 and T13, and inferring the state of the voice. However, since there is no direct reference to the voice state, there may be a problem in deriving the actual voice state.
Therefore, it is possible to precisely derive the state of voice to prepare for the scenario of loss of the control message related to voice acquisition and retrieval due to the packet loss, and to provide a voice control function that enables normal operation even in the packet loss of the wireless communication system in which packet loss occurs frequently A method is needed.
DISCLOSURE Technical Problem The present invention has been made to solve the above-mentioned problems and to provide a group communication service such as Push-to-Talk (PTT), which is indispensable in a special purpose mobile communication system based on LTE, And an object of the present invention is to provide a MCPTT control method for packet loss in a wireless communication system that enables normal operation even in packet loss in a wireless communication system environment where packet loss frequently occurs.
In order to achieve the above object, the present invention provides an MCPTT control method for packet loss in a wireless communication system, which is controlled by being divided into on-network (FIG. 3) and off-network In the case of the on-network, the
In the case of the Off-network, the
In the embodiment, in the case of on-network, after the MCPTT server selects the mobile terminal to take the floor via the floor arbitration process, the Td information is given to the remaining receiving terminals as a floor taken, floor revoke, and floor reject messages.
In the embodiment, in the case of the On-network, the MCPTT server sets the maximum talk time holding time when creating a floor taken / revoke message to be equal to the maximum talk time holding time calculated when generating the immediately preceding floor grant message.
In the embodiment, in the case of the On-network, the MCPTT server sets the same as that calculated from the remaining time in the floor holding time specified in the immediately preceding floor grant when generating the floor rejected message.
In the embodiment, in the off-network case, a terminal acting as an MCPTT server sets a maximum floor holding time derived by itself when a floorRequestStatus (status: granted / revoked) message is generated at the time of generating a floor rejected message to Td.
In the embodiment, in the Off-network case, the terminal acting as the MCPTT server calculates the remaining time from the talk holding time specified in the previous floorRequestStatus (status: granted) when the floorRequestStatus (status: denied) message is generated.
In an embodiment, the receiving terminal receives the floor taken / revoke / rejected message in the on-network case or the floorRequestStatus message in the off-network, stores the maximum floor holding time information, If the floor release message in the on-network or the floorRequestStatus (status: released) message in the off-network is not received after the maximum talk time holding time received afterwards, it is considered that the floor is recovered, The floor release status message can be updated even if the floor release message in the off-network or the floorRequestStatus (status: released) message in the off-network can not be received due to a wireless environment or the like.
In another aspect of the present invention, there is provided an MCPTT control method for packet loss in a wireless communication system, the MCPTT control method being divided into on-network (FIG. 3) and off-network The
In the embodiment, when a floor request is received from a terminal for which call setup has not been performed, it is implicitly excluded from the group call or a group call setup required and rejection cause ) And responds with a floor reject message in the on-network case and a floorRequestStatus (status: denied) message in the off-network case.
In the embodiment, the floor requesting terminal having received the reject message performs a group call setup process to allow the
According to the preferred embodiment of the present invention, even in various situations in which a message related to the voice control of the MCPTT is lost in a wireless environment in which packet loss occurs, the server side and the receiving terminal controlling the voice control are maintained in the same state information on the voice control, The group call service may not be provided smoothly if the talk terminal is misunderstood by the receiving terminal and the talk burst is not requested for a long time. However, the present invention can solve the problem .
Specifically, even if the receiving terminal fails to receive the floor released due to a wireless environment or the like, the talk state can be updated to be the same as the real server state after a predetermined time through the talk time information.
In addition, when a receiving terminal becomes out of network or direct communication coverage, or communication becomes difficult due to power shortage, a terminal acting as an MCPTT server or an MCPTT server can efficiently use radio resources by excluding the terminal from a group , It is possible to effectively cope with the problem even if the mobile station recovers its wireless connectivity.
Brief Description of the Drawings Fig. 1 is a flow chart showing a method of controlling a voice of a conventional PTT over Cellular system.
2 is a flowchart illustrating a method of controlling a voice according to a conventional 3GPP MCPTT.
3 and 4 are block diagrams showing a configuration for implementing the MCPTT control method according to the present invention;
5 is a flowchart illustrating a signal flow in an on-network in the MCPTT control method according to the present invention.
6 is a flowchart illustrating a signal flow in an off network in the MCPTT control method according to the present invention.
FIG. 7 is a flowchart illustrating an asynchronous state of a specific mobile terminal in the MCPTT control method according to the present invention. FIG.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.
3 and 4 are block diagrams showing a configuration for implementing the MCPTT control method according to the present invention. The MCPTT control method according to the present invention can be applied to both an On-network and an off- It is divided into two cases.
In the case of on-network as shown in FIG. 3, the
4, the
Let's take a look at the structural features of these systems.
In both on-network and off-network cases, one of the receiving terminals sends a floor request signal to the MCPTT server or the terminal acting as a floor request when it wants to obtain the floor.
In the On-network as shown in FIG. 3, the MCPTT
In the off-network as shown in FIG. 4, a
On the other hand, a floor taken message is delivered to the remaining mobile terminals in the on-network, and a floor request status message (floorRequestStatus) is transmitted in the off-network case.
In addition, the present invention can be applied to a floor taken, a floor revoke, a floor rejected message, an off-network And informs the receiving terminals by specifying the maximum floor holding time in the floor grant.
In the case of on-network, the MCPTT server sets the maximum floor holding time when floor taken / revoke message is generated to be equal to the maximum floor holding time calculated when floor grant message is generated.
For on-network, the MCPTT server calculates the remaining time from the floor holding time specified in the previous floor grant when the floor rejected message is generated.
In the case of off-network, a terminal acting as an MCPTT server sets a maximum talk time holding time when generating a floorRequestStatus (status: granted / revoked) message as a maximum talk time holding time allocated by itself considering various factors such as priority.
In the off-network case, the terminal acting as the MCPTT server calculates the remaining time from the floor holding time specified in the previous floorRequestStatus (status: granted) when floorRequestStatus (status: denied) message is generated.
After receiving the floor taken / revoked / rejected or floorRequestStatus, the receiving terminal stores the maximum floor holding time information. After receiving the floor taken / revoked / rejected, the receiving terminal stores floor released or floorRequestStatus (status : released), it is assumed that the right to speak has been recovered.
Thus, even if the receiving terminal can not receive the floor released due to the wireless environment or the like, the floor state can be updated to be the same as the actual server state.
The terminal acting as the MCPTT server or the MCPTT server recognizes that the transmission / reception state of the specific receiving terminal is not good, terminates the SIP session, and cancels the registration if necessary.
When a floor request is received from a terminal that has been deregistered or has not been set up in a call setup, it requests a re-registration request or a reconnection request, responds with a floor reject message by specifying a rejection cause, REGISTER) or performs an invite (INVITE).
In this way, when the communication becomes difficult due to the out-of-network or direct communication coverage, power shortage, or the like, the
1) First Embodiment
FIG. 5 is a flowchart illustrating a signal flow in the ON network in the MCPTT control method according to the present invention. The
The
After receiving the floor taken message (3), after the Td time (6), the terminal 2 (22) judges that the floor is withdrawn (7), and then transmits a floor request for the floor request (8)
In the prior art, in the above situation, the mobile terminal 2 (22) can not request a floor right until the next message related to the floor of the
In the case of the terminal 12 acting as an MCPTT server, an embodiment to which the present invention is applied will be described as follows.
2)
FIG. 6 is a flowchart illustrating a signal flow in an off network in the MCPTT control method according to the present invention, which is basically the same as the ON network, but uses a floor grant and a floor taken message in an on- There is a difference in that the floorRequestStatus (granted) single message is used in the off network after the flow request transmission (1) in (21), and the Td information is included in this single message (2).
On the other hand, the signal flow related to the rejection cause is as follows.
FIG. 7 is a flowchart illustrating an asynchronous state of a specific mobile terminal in the MCPTT control method according to the present invention. The mobile terminal 1 (21) transmits voice data (4) in a voice data transmission mode The
The
Thereafter, when the
11;
21;
23;
Claims (11)
In the case of the on-network, the MCPTT server 11 is composed of a plurality of receiving terminal groups such as the mobile terminal 1 to the mobile terminals 3, 21, 22 and 23. The MCPTT server 11 The mobile terminals 1 to 3 (21), (22) and (23) are wirelessly connected to the mobile communication network while being present in the mobile communication network;
In the case of the off-network, the mobile terminal 12 serving as an MCPTT server and the plurality of receiving terminal groups such as the mobile terminal 1 to the mobile terminals 3, 21, 22 and 23, The mobile terminal 12 and the receiving terminals 21, 22, and 23 of the server role are connected through a direct communication method that does not pass the mobile communication network;
In either of the On-network and the off-network, when one of the receiving terminals desires to obtain a floor, a floor request signal is transmitted to the MCPTT server or the terminal serving as the floor request signal;
The MCPTT server 11 selects a receiving terminal to receive the floor right through the floor arbitration process and transmits a floor grant to the terminal that has requested the floor, The talk time holding time (Td) is additionally referred to,
The receiving terminal receives the floor taken / revoke / rejected message in the on-network case or the floorRequestStatus message in the off-network, stores the maximum floor holding time information, After receiving the floor taken status / revoked / rejected message or the floorRequestStatus message in the off-network, the floor released message in the on-network or the floorRequestStatus (status: released) message in the off- , It is assumed that the floor has been retrieved so that the receiving terminal can update the floor state even if it can not receive the floor released message in the on-network or the floorRequestStatus (status: released) message in the off- The MCPTT control method for packet loss in a wireless communication system.
In the case of the Off-network, after the mobile terminal 12 acting as the MCPTT server selects the mobile terminal to take the floor via the floor arbitration process, it transmits the Td information to the remaining receiving terminals through the floor request status message (floorRequestStatus) And the MCPTT control method for packet loss in a wireless communication system.
In the case of on-network, after the MCPTT server selects the mobile terminal to take the floor via the floor arbitration process, the Td information is sent to the remaining receiving terminals as floor take, floor revoke, Wherein the MCPTT message is transmitted through a floor reject message.
Wherein the MCPTT server sets a maximum talk holding time when generating a floor taken / revoke message to be equal to a maximum talk holding time calculated when generating a floor grant message in the on-network. Control method for MCPTT.
Wherein the MCPTT server sets the same time as the remaining time in the floor holding time specified in the immediately preceding floor grant when generating the floor rejected message in the On-network case.
In the case of the off-network, a terminal acting as an MCPTT server sets a maximum talk holding time derived by itself when a floorRequestStatus (status: granted / revoked) message is generated when a floor rejected message is generated, to Td. Of MCPTT for packet loss
Wherein in the off-network case, the terminal acting as the MCPTT server calculates the remaining talk time holding time from the talk time holding time specified in the previous floorRequestStatus (status: granted) when the floorRequestStatus (status: denied) message is generated. MCPTT control method for packet loss of.
In the case of the on-network, the MCPTT server 11 is composed of a plurality of receiving terminal groups such as the mobile terminal 1 to the mobile terminals 3, 21, 22 and 23. The MCPTT server 11 The mobile terminals 1 to 3 (21), (22) and (23) are wirelessly connected to the mobile communication network while being present in the mobile communication network;
In the case of the off-network, the mobile terminal 12 serving as an MCPTT server and the plurality of receiving terminal groups such as the mobile terminal 1 to the mobile terminals 3, 21, 22 and 23, The mobile terminal 12 and the receiving terminals 21, 22, and 23 of the server role are connected through a direct communication method that does not pass the mobile communication network;
When the mobile terminal 1 (21) is transmitting voice data (4) in the voice data transmission mode (5) after acquiring the voice right (1 2 3), the mobile terminal 1 (21) suddenly transitions out of synchronization When the MCPTT server 11 detects a connection problem with the MCPTT server 11 due to a wireless environment (6), the MCPTT server 11 detects the connection (7) and internally releases registration or connection with the mobile terminal 1 (21) ⑧);
Then, when the mobile terminal 1 21 recovers the connection and transmits the floor request for returning the floor request (9), the MCPTT server 11 deletes the implied group call (Implicitly excluded from the group call) or the call reconnection request group call setup required and a rejection cause, and responds with floor reject message for on-network and floorRequestStatus (status: denied) for off-network (⑩);
The MSS 1 21 performs a process of regenerating a group call session through a call setup process (11) after receiving the MCPTT control message .
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| KR1020150113262A KR101669407B1 (en) | 2015-08-11 | 2015-08-11 | the Mission Critical Push-To-Talk control method for packet data loss in mobile radio communication |
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| KR1020150113262A KR101669407B1 (en) | 2015-08-11 | 2015-08-11 | the Mission Critical Push-To-Talk control method for packet data loss in mobile radio communication |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20180050196A (en) * | 2016-11-04 | 2018-05-14 | 삼성전자주식회사 | A method for displaying user information of the mcptt group performing the mcptt service in the off network |
| KR20180051337A (en) * | 2016-11-07 | 2018-05-16 | 삼성전자주식회사 | Method and terminal for performing communication |
| KR20200097361A (en) | 2019-02-07 | 2020-08-19 | 한국철도기술연구원 | Method and apparatus of acquiring periodic individual information for mission cricical system |
| KR20200097364A (en) | 2019-02-07 | 2020-08-19 | 한국철도기술연구원 | Method and apparatus of fusing aperiodic individual information for mission cricical system |
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| US20060008821A1 (en) | 2004-07-12 | 2006-01-12 | Toru Inaba | Biomaterial inspection chip |
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| 3GPP 재난안전망(TSG SA6) 회의(2015.03.04.) 1부.* * |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20180050196A (en) * | 2016-11-04 | 2018-05-14 | 삼성전자주식회사 | A method for displaying user information of the mcptt group performing the mcptt service in the off network |
| KR102255217B1 (en) * | 2016-11-04 | 2021-05-25 | 삼성전자주식회사 | A method for displaying user information of the mcptt group performing the mcptt service in the off network |
| KR20180051337A (en) * | 2016-11-07 | 2018-05-16 | 삼성전자주식회사 | Method and terminal for performing communication |
| KR102022095B1 (en) * | 2016-11-07 | 2019-09-17 | 삼성전자주식회사 | Method and terminal for performing communication |
| KR20200097361A (en) | 2019-02-07 | 2020-08-19 | 한국철도기술연구원 | Method and apparatus of acquiring periodic individual information for mission cricical system |
| KR20200097364A (en) | 2019-02-07 | 2020-08-19 | 한국철도기술연구원 | Method and apparatus of fusing aperiodic individual information for mission cricical system |
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