WO2018146771A1

WO2018146771A1 - Communication system, base station apparatus, communication terminal apparatus and management apparatus

Info

Publication number: WO2018146771A1
Application number: PCT/JP2017/004738
Authority: WO
Inventors: 祐一中井
Original assignee: 三菱電機株式会社
Priority date: 2017-02-09
Filing date: 2017-02-09
Publication date: 2018-08-16

Abstract

A communication system (200) comprises: a communication terminal apparatus (202); and a base station apparatus (203, 207) that is wireless-communicatively connected to the communication terminal apparatus (202). The base station apparatus (203, 207) sets, to zero, the number of medium access control (MAC) retransmissions that is the number of retransmissions of protocol data unit (PDU) in the MAC layer and transmits the setting information of the number of MAC retransmissions to the communication terminal apparatus (202). At least one of the communication terminal apparatus (202) and the base station apparatus (203, 207) carries out no retransmission in the MAC layer in accordance with the setting information of the number of MAC retransmissions. In this way, it is possible to prevent the transport delay between the communication terminal apparatus (202) and the base station apparatus (203, 207).

Description

COMMUNICATION SYSTEM, BASE STATION DEVICE, COMMUNICATION TERMINAL DEVICE, AND MANAGEMENT DEVICE

The present invention relates to a communication system, a base station device, a communication terminal device, and a management device.

The communication system will be described.

The transmission path between the PDN-GW (Packet Data Network Gateway) (also referred to as P-GW) and the UE is called EPS-Bearer (Evolved Packet System-Bearer). The quality of this transmission path is notified from the MME to the eNB. The radio transmission path between the eNB and the UE that constitutes a part of this transmission path is called RB (Radio Bearer) and is managed by the eNB side RRC. The RRC of the eNB receives the QoS setting notification from the MME and notifies the UE side RRC of the parameter setting of the radio protocol stack.

Next, the mapping of IP packets to physical channels will be described.

In the LTE system, the IP packet is divided into data sizes based on the modulation method and bit rate selected according to the communication quality of the wireless transmission path and the assigned radio resource, and subtracting the protocol information in the middle. Sent.

A specific example will be given with reference to FIG. The quality measurement result of the radio transmission path is obtained from the mobile terminal (UE) by the CQI (Channel Quality Indicator), the MAC (Medium Access Control) of the base station apparatus (hereinafter referred to as “E-UTRAN Node B: eNB”). ). The MAC-PDU size is determined by selecting a radio channel modulation scheme and coding rate by selecting MCS (Modulation and Coding Set) and allocating resource blocks (Radio Resource). The MAC-PDU may be accompanied by information that terminates in the MAC layer, and the remaining payload is used for transmission of the RLC-PDU. The RLC-PDU (Radio Link Control-Protocol Data Unit) size is determined by the IP packet size and the RLC layer transmission method.

When retransmission is valid in the RLC layer, RLC-AM (Acknowledged Mode) is applied, and retransmission is performed in RLC-PDU units. When retransmission is invalid in the RLC layer, RLC-UM (Unacknowledged Mode) is applied.

In addition, HARQ (Hybrid Automatic Repeat Request) is applied for retransmission at the MAC layer. By applying FEC (Forward Error Collection) when encoding a MAC-PDU, it is expected to be able to be decoded by overlapping a plurality of partial code receptions. Therefore, it is called Hybrid.

In the prior art, since the MAC-PDU size is determined according to the wireless communication environment, the size is not determined until immediately before the wireless signal is actually transmitted. In order to make full use of the transmittable size, at least one of combining and dividing is performed on the RLC-PDU in accordance with the MAC-PDU size.

Suppose a case in which the divided RLC-PDU is received and the RLC-PDU is extracted. When any one or more of the plurality of MAC-PDUs including the divided RLC-PDUs cause a transmission error, the receiving side cannot reconstruct the RLC-PDUs. Therefore, the reception side waits for a MAC-PDU arrival due to retransmission or a reception error due to timeout.

International Publication No. 2016/068072 Special table 2015-513829 gazette

The background art described above has the following problems.

In the conventional technology, at least one of combining and dividing is performed on the RLC-PDU so as to fit in the MAC-PDU size. When any one or more of the plurality of MAC-PDUs including the divided RLC-PDUs cause a transmission error, the RLC-PDU cannot be reconstructed on the reception side of the divided RLC-PDUs. Therefore, the reception side waits for a MAC-PDU arrival due to retransmission or a reception error due to timeout.

An object of the present invention is to provide a technique capable of preventing a transmission delay between a communication terminal device and a base station device.

The communication system of the present invention is a communication system including a communication terminal device and a base station device connected to the communication terminal device so as to be capable of wireless communication, and the base station device is a MAC (Medium Access Control) layer. The MAC retransmission count, which is the number of retransmissions of a PDU (Protocol Data Unit), is set to 0, the MAC retransmission count setting information is transmitted to the communication terminal device, and the communication terminal device and the base station device At least one of them does not perform retransmission processing in the MAC layer according to the setting information of the number of times of MAC retransmission.

The base station apparatus of the present invention is a base station apparatus connected to a communication terminal apparatus so as to be capable of wireless communication, and the base station apparatus performs PDU (Protocol Data Unit) retransmissions in a MAC (Medium Access Control) layer. The MAC retransmission count is set to 0, and the MAC retransmission count setting information is transmitted to the communication terminal apparatus.

A communication terminal apparatus according to the present invention is a communication terminal apparatus connected to a base station apparatus so as to be able to perform wireless communication, and the communication terminal apparatus performs retransmission of PDU (Protocol Data Unit) in a MAC (Medium Access Control) layer The information indicating that the number of times of MAC retransmission is set to 0 is received from the base station apparatus, and retransmission processing at the MAC layer is not performed according to the received setting information.

Another communication system of the present invention includes a communication terminal device, a base station device connected to the communication terminal device so as to be capable of wireless communication, and management for managing wireless communication between the communication terminal device and the base station device. The management device sets at least one parameter of an upper limit size of an IP (Internet Protocol) packet and an upper limit size of a payload in one or more protocol layers, The parameter setting information is transmitted to the base station apparatus, and the base station apparatus transmits the parameter setting information received from the management apparatus to the communication terminal apparatus, and the base station apparatus and the communication terminal The apparatus performs wireless communication according to the setting information of the parameter.

The management apparatus of the present invention is a management apparatus that manages wireless communication between a communication terminal apparatus and a base station apparatus, and the management apparatus includes an upper limit size of an IP (Internet Protocol) packet and one or more protocols. At least one parameter of the upper limit size of the payload in the layer is set, and the parameter setting information is transmitted to the base station apparatus.

Another base station apparatus of the present invention is a base station apparatus connected to a communication terminal apparatus so as to be capable of wireless communication, wherein the base station apparatus performs wireless communication between the communication terminal apparatus and the base station apparatus. The base station apparatus receives setting information of at least one parameter of an upper limit size of an IP (Internet Protocol) packet and an upper limit size of a payload in one or more protocol layers from a management apparatus that manages the base station apparatus. The received setting information of the parameter is transmitted to the communication terminal apparatus, and the base station apparatus performs wireless communication with the communication terminal apparatus according to the setting information of the parameter.

Another communication terminal apparatus of the present invention is a communication terminal apparatus connected to a base station apparatus so as to be able to perform wireless communication, and the communication terminal apparatus receives setting information of parameters related to wireless communication from the base station apparatus. The parameters relating to wireless communication include at least one of an upper limit size of an IP (Internet Protocol) packet and an upper limit size of a payload in one or more protocol layers. Radio communication is performed with the base station apparatus according to the setting information.

According to the present invention, transmission delay between the communication terminal device and the base station device can be prevented.

The objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description and the accompanying drawings.

It is a figure explaining the relationship of PDCP / RLC / MAC PDU. 1 is a block diagram showing an overall configuration of a communication system 200 according to Embodiment 1. FIG. FIG. 3 is a block diagram showing a configuration of a mobile terminal 202 shown in FIG. FIG. 3 is a block diagram showing a configuration of a base station 203 shown in FIG. It is a block diagram which shows the structure of MME contained in the MME part 204 shown in FIG. It is a figure explaining MAC resending and resending delay. FIG. 10 is a sequence diagram for explaining an EPS-Bearer setting procedure in the first embodiment. FIG. 10 is a diagram illustrating QoS information to which information related to IP packet size restriction is added according to the second embodiment. It is a figure explaining the QoS parameter of a prior art example notified to PDN-GW from MME. FIG. 10 is a diagram for explaining an example of a QoS parameter according to Embodiment 2, which is notified from the MME to the PDN-GW. It is a figure explaining the QoS parameter of a prior art example notified to eNB from MME. It is a figure explaining an example of the QoS parameter based on Embodiment 2 notified to eNB from MME.

Embodiment 1 FIG.
The communication system of the present invention is a system equivalent to or similar to the LTE system in the protocol layer, and the data transmission path required by the communication terminal apparatus can be set for each communication terminal apparatus.

FIG. 2 is a block diagram showing an overall configuration of the communication system 200 according to the first embodiment. With reference to FIG. The radio access network is referred to as E-UTRAN (Evolved Universal Terrestrial Radio Access Network) 201. A mobile terminal device (hereinafter referred to as “mobile terminal (User Equipment: UE)”) 202 that is a communication terminal device is capable of wireless communication with a base station device (hereinafter referred to as “base station (E-UTRAN NodeB: eNB)”) 203. Yes, signals are transmitted and received by wireless communication.

Here, the “communication terminal device” includes not only a mobile terminal device such as a movable mobile phone terminal device but also a non-moving device such as a sensor. In the following description, the “communication terminal device” may be simply referred to as “communication terminal”.

Control protocols for the mobile terminal 202 such as RRC (Radio Resource Control) and user planes such as PDCP (Packet Data Convergence Protocol), RLC (Radio Link Control), MAC (Medium Access Control), PHY (Physical Layer) If terminated at station 203, the E-UTRAN is composed of one or more base stations 203.

A control protocol RRC (Radio Resource Control) between the mobile terminal 202 and the base station 203 performs broadcast, paging, RRC connection management (RRC connection management), and the like. As states of the base station 203 and the mobile terminal 202 in RRC, there are RRC_IDLE and RRC_CONNECTED.

In RRC_IDLE, PLMN (Public Land Mobile Mobile Network) selection, system information (System Information: SI) notification, paging, cell re-selection, mobility, and the like are performed. In RRC_CONNECTED, the mobile terminal has an RRC connection and can send and receive data to and from the network. In RRC_CONNECTED, handover (Handover: HO), measurement of neighbor cells (neighbor cells), etc. are performed.

The base station 203 includes one or more eNBs 207. A system composed of EPC (Evolved Packet Core) as a core network and E-UTRAN 201 as a radio access network is referred to as EPS (Evolved Packet System). The EPC that is the core network and the E-UTRAN 201 that is the radio access network may be collectively referred to as “network”.

The eNB 207 includes a mobility management entity (Mobility Management Entity: MME), an S-GW (Serving Management Gateway), or an MME / S-GW unit including the MME and S-GW (hereinafter also referred to as “MME unit”) 204. The control information is communicated between the eNB 207 and the MME unit 204 through the S1 interface. A plurality of MME units 204 may be connected to one eNB 207. The eNBs 207 are connected by the X2 interface, and control information is communicated between the eNBs 207.

The MME unit 204 is an upper device, specifically, an upper node, and controls connection between the eNB 207 serving as a base station and a mobile terminal (UE) 202. The MME unit 204 constitutes an EPC that is a core network.

FIG. 3 is a block diagram showing a configuration of the mobile terminal 202 shown in FIG. 2, which is a communication terminal according to the present invention. The transmission process of the mobile terminal 202 shown in FIG. 3 will be described. First, control data from the protocol processing unit 301 and user data from the application unit 302 are stored in the transmission data buffer unit 303. The data stored in the transmission data buffer unit 303 is transferred to the encoder unit 304 and subjected to encoding processing such as error correction. There may exist data that is directly output from the transmission data buffer unit 303 to the modulation unit 305 without performing the encoding process. The data encoded by the encoder unit 304 is modulated by the modulation unit 305. The modulated data is converted into a baseband signal, and then output to the frequency conversion unit 306, where it is converted into a radio transmission frequency. Thereafter, a transmission signal is transmitted from the antenna 307 to the base station 203.

Also, the reception process of the mobile terminal 202 is executed as follows. A radio signal from the base station 203 is received by the antenna 307. The received signal is converted from a radio reception frequency to a baseband signal by the frequency converter 306, and demodulated by the demodulator 308. The demodulated data is transferred to the decoder unit 309 and subjected to decoding processing such as error correction. Of the decoded data, control data is passed to the protocol processing unit 301, and user data is passed to the application unit 302. A series of processing of the mobile terminal 202 is controlled by the control unit 310. Therefore, although not shown in FIG. 3, the control unit 310 is connected to the units 301 to 309.

FIG. 4 is a block diagram showing a configuration of the base station 203 shown in FIG. 2, which is a base station according to the present invention. The transmission process of the base station 203 shown in FIG. 4 will be described. The EPC communication unit 401 transmits and receives data between the base station 203 and an EPC (such as the MME unit 204). The other base station communication unit 402 transmits / receives data to / from other base stations. The EPC communication unit 401 and the other base station communication unit 402 exchange information with the protocol processing unit 403, respectively. Control data from the protocol processing unit 403 and user data and control data from the EPC communication unit 401 and the other base station communication unit 402 are stored in the transmission data buffer unit 404.

The data stored in the transmission data buffer unit 404 is passed to the encoder unit 405 and subjected to encoding processing such as error correction. There may exist data directly output from the transmission data buffer unit 404 to the modulation unit 406 without performing the encoding process. The encoded data is subjected to modulation processing by the modulation unit 406. The modulated data is converted into a baseband signal and then output to the frequency conversion unit 407 where it is converted into a radio transmission frequency. Thereafter, a transmission signal is transmitted from the antenna 408 to one or a plurality of mobile terminals 202.

Further, the reception processing of the base station 203 is executed as follows. Radio signals from one or more mobile terminals 202 are received by the antenna 408. The received signal is converted from a radio reception frequency to a baseband signal by the frequency conversion unit 407, and demodulated by the demodulation unit 409. The demodulated data is transferred to the decoder unit 410 and subjected to decoding processing such as error correction. Among the decoded data, control data is passed to the protocol processing unit 403, EPC communication unit 401, or other base station communication unit 402, and user data is passed to the EPC communication unit 401 and other base station communication unit 402. A series of processing of the base station 203 is controlled by the control unit 411. Therefore, although not shown in FIG. 4, the control unit 411 is connected to the units 401 to 410.

FIG. 5 is a block diagram showing the configuration of the MME according to the present invention. FIG. 5 shows the configuration of the MME 204a included in the MME unit 204 shown in FIG. The PDN-GW communication unit 501 transmits and receives data between the MME 204a and the PDN-GW 213. The base station communication unit 502 performs data transmission / reception between the MME 204a and the base station 203 using the S1 interface. When the data received from the PDN-GW 213 is user data, the user data is passed from the PDN-GW communication unit 501 to the base station communication unit 502 via the user plane communication unit 503, and one or more base stations 203. When the data received from the base station 203 is user data, the user data is passed from the base station communication unit 502 to the PDN-GW communication unit 501 via the user plane communication unit 503 and transmitted to the PDN-GW 213. .

When the data received from the PDN-GW 213 is control data, the control data is transferred from the PDN-GW communication unit 501 to the control plane control unit 505. When the data received from the base station 203 is control data, the control data is transferred from the base station communication unit 502 to the control plane control unit 505.

The control plane control unit 505 includes a NAS security unit 505-1, an SAE bearer control unit 505-2, an idle state mobility management unit 505-3, and the like, and performs overall processing for the control plane. The NAS security unit 505-1 performs security of a NAS (Non-Access Stratum) message. The SAE bearer control unit 505-2 performs management of SAE (System Architecture) Evolution bearers and the like. The idle state mobility management unit 505-3 performs mobility management in a standby state (idle state; also referred to as LTE-IDLE state or simply idle), generation and control of a paging signal in the standby state, The tracking area of one or more mobile terminals 202 is added, deleted, updated and searched, and the tracking area list is managed.

The MME 204a distributes the paging signal to one or a plurality of base stations 203. Further, the MME 204a performs mobility control (Mobility control) in a standby state (Idle State). The MME 204a manages a tracking area list when the mobile terminal is in a standby state and in an active state (Active State). The MME 204a starts a paging protocol by transmitting a paging message to a cell belonging to a tracking area (tracking area: TrackingTrackArea) where the UE is registered.

The MAC retransmission will be described with reference to FIG. Here, consider a case where the reception of the PDU indicated by (2) in FIG. 6 fails. Between the UE and the eNB, a channel for notifying the success or failure of reception of the MAC-PDU from the UE to the eNB is provided, and when the eNB determines that it is NACK, the eNB retransmits the corresponding MAC-PDU. The MAC-PDU is provided with a sequence number for HARQ and a flag for identifying whether it is new transmission or retransmission, and the receiving side can easily manage the MAC-PDU.

Since retransmission of MAC-PDU requires time required for NACK notification, preparation time for retransmission of MAC-PDU, and transmission time of MAC-PDU, at least a delay of several frames occurs. In the case of the TDD system, in order to notify ACK / NACK, it is necessary to wait for UplinkFrame, and since this waiting time is also added to the delay time, the delay becomes significant.

A system in which a transmission delay due to retransmission control occurs cannot be used for a service that cannot tolerate the delay associated with retransmission control. If the service is such that information is periodically overwritten with data that becomes worthless when a transmission delay occurs, it is desirable to discard the data instead of resending it. With regard to transmission delay in EPC, measures to shorten the delay time by performing priority control or physical arrangement according to the application can be considered.

Embodiment 1 discloses a method for solving such a problem.

An example of the EPS-Bearer setting procedure will be described with reference to FIG.

In step ST1, a Bearer update request (Modify Bearer Command) is sent from the MME to the PDN-GW, and at least one of addition and change is performed on the Bearer setting of the user plane.

In Step ST2, after updating the higher Bearer, a Bearer Setup Request message is sent to the eNB, and at least one of addition and change is performed on the Bearer setting between the MME and the UE.

In step ST3, the eNB updates the RB setting between the eNB and the UE according to the request. Here, the conventional technique has a problem that the number of uplink MAC retransmissions can be set to only one or more for the UE, and a packet transmission delay occurs when retransmission occurs on the wireless transmission path. On the other hand, in the first embodiment, the number of retransmissions can be reduced to 0, and transmission delay due to MAC retransmission can be prevented.

In step ST4, a Session Management Response is transmitted from the UE to the MME to notify the completion of setting.

Here, the detailed operation of the UE that uses a service that requires low delay will be described.

<Descent>
In response to the downlink transmission request, in step ST2 of FIG. 7, the eNB determines the number of MAC retransmissions by a Bearer Setup Request message. When a low delay is required so that the retransmission at the MAC layer needs to be zero, the MAC layer does not retransmit the MAC-PDU and discards the MAC-PDU regardless of the success or failure of the transmission.

The eNB instructs the number of MAC retransmissions using maxHARQ-Tx included in RRC Connection Reconfiguration that the eNB issues to the UE in Step ST3 of FIG. The eNB notifies the UE of the number of MAC retransmissions, but setting the number of retransmissions in the MAC layer to 0 in order to reduce the delay time is not defined in the conventional IE (Information Element). Specifically, in the IE of the prior art, 1 to 8, 10, 12, 16, 20, 24, and 28 are defined as the value of the number of retransmissions in the MAC layer, but the number of retransmissions 0 is not defined. . In contrast, in the first embodiment, the number of retransmissions 0 in the MAC layer is additionally defined. If there are zero retransmissions at the MAC layer, the UE may return a transmission completion notification (ACK / NACK) to the eNB, or omit such transmission completion notification to save radio resources. Also good.

<Upbound>
In response to an uplink transmission request from the UE, in step ST3 of FIG. 7, the MAC retransmission count is instructed using maxHARQ-Tx included in the RRC Connection Reconfiguration issued by the eNB to the UE. The eNB notifies the UE of the number of MAC retransmissions, but setting the number of retransmissions at the MAC layer to 0 in order to reduce the delay time is not defined in the IE (Information Element) of the prior art. Specifically, in the IE of the prior art, 1 to 8, 10, 12, 16, 20, 24, and 28 are defined as the value of the number of retransmissions in the MAC layer, but the number of retransmissions 0 is not defined. . In contrast, in the first embodiment, the number of retransmissions 0 in the MAC layer is additionally defined. In response to this instruction, the UE sets the retransmission processing in the MAC layer not to be performed.

Thereby, the first embodiment has the following effects.

For IP packets that transmit data that is no longer useful due to transmission delay, by setting the MAC retransmission to zero, the increase in transmission delay due to retransmission can be reliably reduced.

In the prior art, IP packet loss is reduced by performing MAC retransmission in response to a radio transmission error, so there is a concern about an increase in PELR (Packet Error Loss Rate) associated with changing the number of retransmissions. In order to solve this, in the radio resource management unit included in the control unit of the eNB (see the control unit 411 in FIG. 4), compared with the normal time (in other words, compared to the case where the MAC retransmission is set once or more). The selection MCS is performed so as to select a modulation scheme that can obtain higher quality.

According to Embodiment 1, for example, the following configuration is provided.

A communication system including a communication terminal device and a base station device connected to the communication terminal device so as to be capable of wireless communication is provided. More specifically, the base station apparatus sets the MAC retransmission count, which is the number of retransmissions of the PDU (Protocol Data Unit) in the MAC (Medium Access Control) layer, to 0, and sets the MAC retransmission count setting information as a communication terminal. Send to device. At least one of the communication terminal device and the base station device does not perform retransmission processing at the MAC layer according to the setting information of the MAC retransmission count.

Provided is a base station device connected to a communication terminal device so as to be capable of wireless communication. More specifically, the base station apparatus sets the number of MAC retransmissions, which is the number of PDU retransmissions in the MAC layer, to 0, and transmits the MAC retransmission number setting information to the communication terminal apparatus. Here, the base station apparatus may not perform the retransmission process in the MAC layer according to the setting information of the MAC retransmission count.

A communication terminal device connected to the base station device so as to be able to perform wireless communication is provided. More specifically, the communication terminal apparatus receives information from the base station apparatus that the number of MAC retransmissions, which is the number of retransmissions of PDUs in the MAC layer, is set to 0, and the MAC according to the received setting information. Do not perform retransmission at the layer.

When various elements in these configurations are associated with the elements described in FIG. 2, for example, the communication terminal apparatus corresponds to the mobile terminal 202, the base station apparatus corresponds to the base station 203 or the eNB 207, and the communication system corresponds to the communication system 200. Corresponding to

According to these configurations, various effects described above and below can be obtained.

Embodiment 2. FIG.
Consider the first embodiment described above. As described above, an IP packet may be divided into a plurality of MAC-PDUs and transmitted. In this case, the IP packet cannot be reconstructed unless all the MAC-PDUs can be normally transmitted. Therefore, the time from the completion of reception of the first MAC-PDU to the completion of reception of the second MAC-PDU is a transmission delay. In the second embodiment, a method for solving such a problem is disclosed.

In order to prevent the IP packet from being divided into a plurality of MAC-PDUs, the limit value (upper limit value) of the IP packet size to be transmitted is defined in the QoS information described above. Specifically, as shown in FIG. 8, an IP packet size limit value “IP packet maximum” size ”is added to the QoS information. The IP packet can be given and deleted protocol overhead in each of the PDN-GW, S-GW, eNB, and UE. For this reason, it is necessary to derive the PDU size in each protocol according to the upper limit of the IP packet size.

Here, when the MAC-PDU is generated from the RLC-PDU in the eNB, a plurality of RLC-PDUs are combined, and the combined RLC-PDU is divided so as to embed all the payloads of the MAC-PDU, thereby mapping. I was going. However, since this process also causes transmission delay as described above, the PDU combining / dividing process in the RLC layer is also invalidated.

The notification of the IP packet size from the eNB to the UE is performed in RRC Connection Reconfiguration IE used in step ST3 in FIG. 7, and the UE control unit (see the control unit 310 in FIG. 3) performs the protocol processing unit (protocol in FIG. 3). This is realized by controlling the processing unit 301).

・ When data exceeding the upper limit of payload size is received in each device or each layer, it is immediately discarded. Thereby, it is possible to expect an effect of reducing downstream traffic and preventing an increase in delay time and power consumption due to unnecessary processing.

FIG. 9 shows a conventional QoS parameter notified from the MME to the PDN-GW. On the other hand, in the second embodiment, an upper limit of the IP packet payload size is added, and “Maximum bytes of IP packet payload” is defined as illustrated in FIG. The QoS parameters in FIG. 10 are used in step ST1 in FIG. In the IP packet payload size, a value for notifying the size of the payload data portion flowing to RadioRadBearer is set.

FIG. 11 shows conventional QoS parameters notified from the MME to the eNB. In contrast, FIG. 12 shows QoS parameters according to the second embodiment notified from the MME to the eNB. As can be seen from FIG. 12, the parameters required in the second embodiment are added to the parameters of FIG. The QoS parameters in FIG. 12 are used in step ST4 in FIG.

On the other hand, in the eNB, it is necessary to steadily secure radio resources so that an IP packet in which the upper limit of the payload size is regulated with the UE can always be transmitted by one MAC-PDU. In data transmission from the UE to the eNB, the existing technology requires a large overhead because the UE needs to obtain a grant from the eNB for data transmission. As an example of the realizing means, information for allocating an uplink radio resource called Semi-Persistant in an existing RRC Configuration information element at a constant interval is used.

According to the second embodiment, for example, the following configuration is provided.

There is provided a communication system including a communication terminal device, a base station device connected to the communication terminal device so as to be capable of wireless communication, and a management device that manages wireless communication between the communication terminal device and the base station device. More specifically, the management device sets at least one parameter of an upper limit size of an IP (Internet Protocol) packet and an upper limit size of a payload in one or more protocol layers, and sets parameter setting information. Transmit to the base station device. The base station apparatus transmits the parameter setting information received from the management apparatus to the communication terminal apparatus. The base station apparatus and the communication terminal apparatus perform wireless communication according to parameter setting information.

A management device for managing wireless communication between a communication terminal device and a base station device is provided. More specifically, the management apparatus sets at least one parameter of the upper limit size of the IP packet and the upper limit size of the payload in one or more protocol layers, and sets the parameter setting information to the base station apparatus. Send.

Provided is a base station device connected to a communication terminal device so as to be capable of wireless communication. More specifically, the base station device receives an upper limit size of the IP packet and an upper limit size of the payload in one or more protocol layers from the management device that manages wireless communication between the communication terminal device and the base station device. , Setting information of at least one of the parameters is received. The base station apparatus transmits the received parameter setting information to the communication terminal apparatus. The base station apparatus performs wireless communication with the communication terminal apparatus according to the parameter setting information.

A communication terminal device connected to the base station device so as to be able to perform wireless communication is provided. More specifically, the communication terminal apparatus receives parameter setting information related to wireless communication from the base station apparatus. Here, the parameter relating to wireless communication includes at least one of an upper limit size of an IP packet and an upper limit size of a payload in one or more protocol layers. The communication terminal apparatus performs wireless communication with the base station apparatus according to the parameter setting information.

When various elements in these configurations are associated with, for example, the elements described in FIG. 2, the communication terminal apparatus corresponds to the mobile terminal 202, the base station apparatus corresponds to the base station 203 or the eNB 207, and the management apparatus corresponds to the MME unit ( MME / S-GW unit) 204 or MME 204a (see FIG. 5), and the communication system corresponds to communication system 200.

According to the first and second embodiments, the radio communication protocol applied to the logical transmission path configured with the base station is controlled according to the service used by the communication terminal. Specifically, at least one of adjustment including presence / absence of retransmission control and capacity limitation for each packet on the network side are performed. As a result, radio resources can be easily arranged. In addition, the transmission quality of the radio section can be arbitrarily adjusted. Furthermore, by eliminating retransmission, it is possible to provide a transmission path that does not increase transmission delay. Also, by improving the transmission quality, it is possible to prevent transmission failure.

Also, according to at least one of invalidation of retransmission control and restriction of packet size, resources such as a storage device of a terminal device, such as a memory, can be reduced. Thereby, reduction of terminal cost and power consumption can be expected.

The present invention can be applied not only to the LTE system as described above but also to the next generation 5G system.

The above-mentioned 0 times of MAC retransmissions can be applied not only to HARQ in the protocol stack of the wireless transmission path but also to ARQ (Automatic Repeat reQuest). In addition, without referring to retransmission in the MAC layer, the LTE system includes setting the number of retransmissions in the RLC layer to zero. However, the RLC layer retransmission control count 0 in the LTE system is defined as RLC-UM (Unacknowredge Mode), and the configuration in which there is no retransmission in RLC-AM (Acknowredge Mode) has no operational merit, so it is not considered.

The above-mentioned wireless protocol stack is (a) independent of the name / number of layers such as PDCP, RLC, MAC in the LTE system, (b) giving control information to data to be transmitted, and (c) between layers And (d) a mechanism for transmitting payload data in a wireless section.

The technical idea of the present invention can be used in the following system, for example. A system having means for notifying at least one of the number of retransmissions, a maximum payload size, and an allowable delay time (Delay Budget) to a protocol stack in a radio section. A system in which the retransmission function can be disabled by setting the number of retransmissions to zero. A system that can suppress the occurrence of fragments by setting the maximum payload size.

The technical idea of the present invention is realized by setting the number of retransmissions at the MAC layer to 0 or including a limit value (upper limit value) of the IP packet size to be transmitted in the notification means described above. be able to.

The above-described embodiments and modifications thereof are merely examples of the present invention, and the embodiments and modifications thereof can be freely combined within the scope of the present invention. In addition, arbitrary components of each embodiment and its modification examples can be appropriately changed or omitted.

Although the present invention has been described in detail, the above description is illustrative in all aspects, and the present invention is not limited thereto. It is understood that countless variations that are not illustrated can be envisaged without departing from the scope of the present invention.

202 communication terminal device, 203, 207 base station device, 200 communication system, 204, 204a management device.

Claims

A communication system comprising a communication terminal device and a base station device connected to the communication terminal device so as to be capable of wireless communication,
The base station apparatus sets a MAC retransmission count that is the number of retransmissions of a PDU (Protocol Data Unit) in a MAC (Medium Access Control) layer to 0, and transmits the MAC retransmission count setting information to the communication terminal apparatus And
At least one of the communication terminal device and the base station device does not perform retransmission processing in the MAC layer according to the setting information of the MAC retransmission count,
Communications system.
A base station device connected to a communication terminal device so that wireless communication is possible,
The base station apparatus sets a MAC retransmission count that is the number of retransmissions of a PDU (Protocol Data Unit) in a MAC (Medium Access Control) layer to 0, and transmits the MAC retransmission count setting information to the communication terminal apparatus To
Base station device.
The base station apparatus according to claim 2, wherein the base station apparatus does not perform retransmission processing in the MAC layer according to the setting information of the MAC retransmission count.
A communication terminal device connected to a base station device so as to be capable of wireless communication,
The communication terminal apparatus receives, from the base station apparatus, information indicating that the number of MAC retransmissions, which is the number of retransmissions of a PDU (Protocol Data Unit) in a MAC (Medium Access Control) layer, is set to zero. In accordance with the set information, the retransmission processing in the MAC layer is not performed.
Communication terminal device.
A communication system comprising: a communication terminal device; a base station device connected to the communication terminal device so as to be capable of wireless communication; and a management device that manages wireless communication between the communication terminal device and the base station device. ,
The management apparatus sets at least one parameter of an upper limit size of an IP (Internet Protocol) packet and an upper limit size of a payload in one or more protocol layers, and sets the parameter setting information as the base station apparatus To
The base station device transmits the setting information of the parameter received from the management device to the communication terminal device;
The base station device and the communication terminal device perform wireless communication according to the setting information of the parameter.
Communications system.
A management device that manages wireless communication between a communication terminal device and a base station device,
The management apparatus sets at least one parameter of an upper limit size of an IP (Internet Protocol) packet and an upper limit size of a payload in one or more protocol layers, and sets the parameter setting information as the base station apparatus Send to
Management device.
A base station device connected to a communication terminal device so that wireless communication is possible,
The base station apparatus receives an upper limit size of an IP (Internet Protocol) packet and an upper limit size of a payload in one or more protocol layers from a management apparatus that manages wireless communication between the communication terminal apparatus and the base station apparatus. And receiving setting information of at least one of the parameters,
The base station device transmits the received setting information of the parameter to the communication terminal device,
The base station device performs wireless communication with the communication terminal device according to the setting information of the parameter.
Base station device.
A communication terminal device connected to a base station device so as to be capable of wireless communication,
The communication terminal apparatus receives parameter setting information related to radio communication from the base station apparatus,
The wireless communication parameters include at least one of an upper limit size of an IP (Internet Protocol) packet and an upper limit size of a payload in one or more protocol layers,
The communication terminal apparatus performs wireless communication with the base station apparatus according to the setting information of the parameter.
Communication terminal device.