Specification

Title: RADIO COMMUNICATION SYSTEM, BASE STATION AND MOBILE STATION
Technical field

[0001]
　The present invention relates to a radio communication system, a base station, and a mobile station.
BACKGROUND ART

[0002]
　Conventionally, mobile communication such as LTE (Long Term Evolution) is known (for example, refer to Non-Patent Documents 1 to 14 below). In LTE, aggregation that cooperates with WLAN (Wireless Local Area Network) at a level of radio access has been studied (for example, see Non-Patent Documents 15 to 17 below).
[0003]
　In addition, when a WLAN is used, a technique of transferring data from RRC (Radio Resource Control) to MAC (Media Access Control) layer is known (for example, see the following Patent Document 1). . Also, a technique for sharing LTE PDCP (Packet Data Convergence Protocol) between LTE and WLAN is known (see, for example, Patent Document 2 below). Further, in WLAN or the like, a technique for controlling transmission of data based on QoS (Quality of Service) information is known.
Prior Art Document

Patent literature

[0004]
Patent Document 1: International Publication No. 2012/121757
Patent Document 2: International Publication No. 2013/068787
Non-patent literature

[0005]
Non-patent document 1: 3 GPP TS 36.300 v 12.1.0, March 2014
Non-patent document 2: 3 GPP TS 36.211 v 12.1.0, March 2014
Non-Patent Document 3: 3 GPP TS 36.212 v 12.0 . 0, December 2013
Non-Patent Document 4: 3 GPP TS 36.213 v 12.1.0, March 2014
Non-Patent Document 5: 3 GPP TS 36.321 v 12.0.0, December 2013
Non-Patent Document 6: 3GPP TS 36.322 v 11.0.0, September 2012
Non-Patent Document 7: 3 GPP TS 36.323 v 11.2.0, March 2013
Non-Patent Document 8: 3 GPP TS 36.331 v 12.0.0, 2013 December
Non-patent document 9: 3
GPP TS 36.413 v 12.0.0 , December 2013 Non-Patent Document 10: 3 GPP TS 36.423 v 12. 0.0, December 2013
Non-Patent Document 11: 3 GPP TR 36.842 v 12.0.0, December 2013
Non-Patent Document 12: 3 GPP TR 37.834 v 12.0.0, December 2013
Non-Patent Document 13 : 3GPP TS 24.301 v 12.6.0, September 2014
Non-Patent Document 14: 3 GPP TS 23.401 v 13.1.0, December 2014
Non-Patent Document 15: 3 GPP RWS-140027, June 2014
Non- Reference 16: 3 GPP RP-140237, March 2014
Non-patent document 17: 3 GPP RP-142281, December 2014
Summary of the invention

Problem to be Solved by Invention

[0006]
　However, in the above-described conventional technique, for example, when processing such as concealment is performed on the header of data by PDCP or the like when offloading LTE data to the WLAN by radio control of LTE, it is included in the data in the WLAN QoS information can not be referenced. For this reason, transmission control of data based on QoS information can not be performed in the WLAN, and the communication quality when offloading to the WLAN may deteriorate in some cases.
[0007]
　In one aspect, an object of the present invention is to provide a radio communication system, a base station, and a mobile station capable of suppressing deterioration in communication quality or maintaining communication quality.
Means for solving the problem

[0008]
　According to an aspect of the present invention, in order to solve the above-mentioned problems and achieve the object, the base station transmits a second wireless communication different from the first wireless communication by a control unit that controls the first wireless communication , And the mobile station can perform data transmission with the base station using the first radio communication or the second radio communication, and the mobile station can perform data transmission between the base station and the mobile station When transmitting data by using the second wireless communication, the processing unit for performing the first wireless communication in the station on the transmitting side out of the base station and the mobile station transmits the first wireless communication Establishing a convergence point for performing the convergence point at the convergence point, making the quality of service information included in the data transparent, and transmitting the data to a station on the receiving side among the base station and the mobile station Systems, base stations and mobile stations are proposed.
Effect of the Invention

[0009]
　According to one aspect of the present invention, it is possible to suppress deterioration in communication quality or maintain communication quality.
Brief Description of the Drawings

[0010]
FIG. 1 is a diagram showing an example of a wireless communication system according to a first embodiment. FIG. 2 is a diagram showing an example of a wireless communication system according to a second embodiment. 3 is a diagram showing an example of a terminal according to Embodiment 2. FIG. FIG. 4 is a diagram showing an example of a hardware configuration of a terminal according to a second embodiment. FIG. 5 is a diagram showing an example of a base station according to a second embodiment. FIG. 6 is a diagram showing an example of a hardware configuration of a base station according to a second embodiment. FIG. 7 is a diagram showing an example of a protocol stack in the wireless communication system according to the second embodiment. FIG. 8 is a diagram showing an example of layer 2 in the wireless communication system according to the second embodiment. 9 is a diagram showing an example of an IP header of an IP packet to be transmitted in the wireless communication system according to the second embodiment. FIG. FIG. 10 is a diagram illustrating an example of values ​​of ToS fields included in an IP header of an IP packet transmitted in the wireless communication system according to the second embodiment. FIG. 11 is a diagram showing an example of aggregation by LTE-A and WLAN in the radio communication system according to the second embodiment. FIG. 12 is a diagram showing an example of QoS control based on a ToS field in the radio communication system according to the second embodiment. FIG. 13 is a diagram showing an example of AC classification in the wireless communication system according to the second embodiment.

[FIG. 14] FIG. 14 is a diagram showing an example of offload in the wireless communication system according to the second embodiment. 15 is a diagram showing an example of the mapping of the QoS class to AC applicable to the wireless communication system according to the second embodiment. FIG. FIG. 16 is a flowchart showing an example of processing by a transmission-side apparatus in the radio communication system according to the second embodiment. FIG. 17 is a diagram showing an example of a case where a plurality of EPS bearers have the same QoS class in the radio communication system according to the second embodiment. FIG. 18 is a diagram showing an example of a method for identifying an EPS bearer using UL TFTs in the radio communication system according to the third embodiment. FIG. 19 is a diagram showing another example of a method for identifying EPS bearers using UL TFTs in the radio communication system according to the third embodiment. FIG. 20 is a diagram showing an example of a TFT acquisition method in the radio communication system according to the third embodiment. FIG. 21 is a diagram showing an example of a method for identifying an EPS bearer using a DL TFT in the wireless communication system according to the third embodiment. FIG. 22 is a diagram showing another example of a method of identifying EPS bearers using DL TFTs in the radio communication system according to the third embodiment. 23 is a diagram showing an example of a method for identifying an EPS bearer by using a virtual IP flow in the wireless communication system according to the third embodiment. FIG.

FIG. 24 is a diagram showing another example of a method of identifying an EPS bearer using a virtual IP flow in the wireless communication system according to the third embodiment. 25 is a diagram showing an example of a method of identifying an EPS bearer using a VLAN in the wireless communication system according to the third embodiment. FIG. FIG. 26 is a diagram showing another example of a method of identifying EPS bearers using VLANs in the radio communication system according to the third embodiment. FIG. 27 is a diagram showing an example of a method for identifying an EPS bearer using GRE tunneling in the radio communication system according to the third embodiment. FIG. 28 is a diagram showing another example of a method for identifying an EPS bearer using GRE tunneling in the radio communication system according to the third embodiment.

MODE FOR CARRYING OUT THE INVENTION

[0011]
　Embodiments of a radio communication system, a base station, and a mobile station according to the present invention will be described in detail below with reference to the drawings.
[0012]
First Embodiment
　FIG. 1 is a diagram showing an example of a radio communication system according to a first embodiment. As shown in FIG. 1 (a), the radio communication system 100 according to the first embodiment includes a base station 110 and a mobile station 120. In the wireless communication system 100, it is possible to perform data transmission using the first wireless communication 101 and data transmission using the second wireless communication 102 between the base station 110 and the mobile station 120.
[0013]
　The first wireless communication 101 and the second wireless communication 102 are mutually different wireless communication (wireless communication method). The first wireless communication 101 is a cellular communication such as LTE or LTE-A as an example. The second wireless communication 102 is, for example, a WLAN. However, the first wireless communication 101 and the second wireless communication 102 are not limited to these, and communication of various methods can be used. In the example shown in FIG. 1 (a), the base station 110 is a base station capable of performing a first wireless communication 101 and a second wireless communication 102 with, for example, the mobile station 120.
[0014]
　When data is transmitted using the first wireless communication 101 without using the first wireless communication 102, the base station 110 and the mobile station 120 transmit the data of the first wireless communication 101 at a first Of the radio communication 101 between the base station 110 and the mobile station 120. Then, the base station 110 and the mobile station 120 transmit data through the communication path of the set first wireless communication 101.
[0015]
　When data is transmitted using the second wireless communication 102, the base station 110 and the mobile station 120 communicate with each other through a communication path of the second wireless communication 102 for transmitting data of the first wireless communication 101 And sets it between the base station 110 and the mobile station 120. Then, the base station 110 and the mobile station 120 transmit data through the established communication path of the second wireless communication 102.
[0016]
　First, the downlink that transmits data from the base station 110 to the mobile station 120 will be described. The base station 110 includes a control unit 111 and a processing unit 112. The control unit 111 controls the first wireless communication 101. Further, the control unit 111 controls the second wireless communication 102. As an example, the control unit 111 is a processing unit such as RRC that performs radio control between the base station 110 and the mobile station 120. However, the control unit 111 is not limited to the RRC, but may be various processing units that control the first wireless communication 101.
[0017]
　The processing unit 112 performs processing for performing the first wireless communication 101. As an example, the processing unit 112 is a data link layer processing unit such as PDCP, RLC (Radio Link Control), MAC, etc. However, the processing unit 112 is not limited thereto, and various processing units for performing the first wireless communication 101 can be used.
[0018]
　The processing of the processing unit 112 for performing the first wireless communication 101 is controlled by the control unit 111. When the processing unit 112 transmits data from the base station 110 to the mobile station 120 using the wireless communication of the second wireless communication 102, the processing unit 112 establishes a convergence point for performing the first wireless communication 101. This convergence point is a process for selecting data to be transmitted between the base station 110 and the mobile station 120 by selecting the first wireless communication 101 and the second wireless communication 102 (presence / absence of offload to be described later) is there. The convergence point is also sometimes called a termination point, a branch point, a split function, a routing function, and if it means that the data becomes a schedule point in the first wireless communication and the second wireless communication, such a designation . In the following, convergence points are used as such representative designations.
[0019]
　At the established convergence point, the processing unit 112 transmits the service quality information included in the data to be transmitted to the mobile station 120, and transmits the data to the mobile station 120. The service quality information is information indicating the priority of transmission, for example, the service class of data. As an example, the service quality information is QoS information such as ToS (Type of Service) field included in the header of the data. However, the quality of service information is not limited to this, and various kinds of information indicating the priority of data transmission can be used. For example, in a VLAN (Virtual Local Area Network), a field specifying QoS is defined in a VLAN tag. Also, more generally, the QoS information is information set with 5 tuples. The 5-tuple is the source IP address and port number, the destination IP address and port number, and the protocol type.
[0020]
　For example, when transmitting data from the base station 110 to the mobile station 120 using the first wireless communication 101 without using the second wireless communication 102, the processing unit 112 performs predetermined processing I do. The predetermined process is, for example, a process of making it impossible to reference the service quality information included in the data to be transmitted in the process of the second radio communication 102. For example, the predetermined process is a process including at least one of concealment, header compression, and addition of a sequence number. As an example, the predetermined processing is PDCP processing. However, the predetermined process is not limited to this, and it may be various processes for making it impossible to reference the service quality information in the process of the second wireless communication 102.
[0021]
　Further, when transmitting data to the mobile station 120 using the second wireless communication 102, the processing unit 112 refers to the service quality information included in the data to be transmitted to the second wireless And does not perform the above-described predetermined processing for making it impossible in the processing of the communication 102. This makes it possible to refer to the service quality information in the processing of the second wireless communication 102 with respect to the data to be transmitted using the second wireless communication 102. Therefore, for data to be transmitted, transmission control based on the service quality information becomes possible in the processing of the second wireless communication 102. Transmission control based on the service quality information is, for example, QoS control that controls the priority of transmission according to the quality of service information. However, the transmission control based on the service quality information is not limited to this, and can be various types of control.
[0022]
　The mobile station 120 receives data transmitted from the base station 110 by at least one of the first wireless communication 101 and the second wireless communication 102. In this way, by efficiently transmitting data from the base station 110 to the mobile station 120 to the first wireless communication 101 and the second wireless communication 102, the efficiency of data transmission can be improved.
[0023]
　Next, the uplink that transmits data from the mobile station 120 to the base station 110 will be described. The mobile station 120 includes a processing unit 121. Like the processing unit 112 of the base station 110, the processing unit 121 is a processing unit for performing the first wireless communication 101. As an example, the processing unit 121 is a data link layer processing unit such as PDCP, RLC, MAC, etc. However, the processing unit 121 is not limited thereto, and various processing units for performing the first wireless communication 101 can be used.
[0024]
　The processing of the processing unit 121 for performing the first wireless communication 101 is controlled by the control unit 111 of the base station 110. When the processing unit 121 transmits data from the mobile station 120 to the base station 110 using the wireless communication of the second wireless communication 102, the processing unit 121 establishes a convergence point for performing the first wireless communication 101. As described above, this convergence point is obtained by selecting data to be transmitted between the base station 110 and the mobile station 120 by selecting the first wireless communication 101 and the second wireless communication 102 (presence / absence of offload to be described later) And is also referred to as a termination point or a branch point.
[0025]
　The processing unit 121 transmits the service quality information included in the data to be transmitted to the base station 110 at the established convergence point, and transmits the data to the base station 110. As described above, the service quality information is information indicating the priority of transmission, for example, the service class of data.
[0026]
　For example, when the processing unit 121 transmits data from the mobile station 120 to the base station 110 using the first wireless communication 101 without using the second wireless communication 102, the processing unit 121 performs predetermined processing I do. As described above, the predetermined process is a process of making it impossible to reference the service quality information included in the data to be transmitted in the processing of the second wireless communication 102.
[0027]
　Further, when transmitting data to the base station 110 using the second wireless communication 102, the processing unit 121 refers to the service quality information included in the data to be transmitted to the second wireless And does not perform the above-described predetermined processing for making it impossible in the processing of the communication 102. This makes it possible to refer to the service quality information in the processing of the second wireless communication 102 for the data to be transmitted using the second wireless communication 102. Therefore, for data to be transmitted, transmission control based on the service quality information becomes possible in the processing of the second wireless communication 102. As described above, the transmission control based on the service quality information is QoS control for controlling the priority of transmission according to the service quality information, for example.
[0028]
　The base station 110 receives data transmitted from the mobile station 120 by at least one of the first wireless communication 101 and the second wireless communication 102. In this way, by distributing the data from the mobile station 120 to the base station 110 to the first wireless communication 101 and the second wireless communication 102, the efficiency of data transmission can be improved.
[0029]
　As described above, when data transmission is performed using the second wireless communication 102 under the control of the control unit 111 of the first wireless communication 101, the transmission-side station of the base station 110 and the mobile station 120 transmits the 1 makes the service quality information transparent in the processing unit of the wireless communication 101.
[0030]
　As a result, the transmission side station among the base station 110 and the mobile station 120 can perform transmission control according to the service quality information in the data transmission processing in the second radio communication 102. Therefore, it is possible to suppress degradation of communication quality by transmitting data using the second wireless communication 102, or maintain communication quality.
[0031]
　In FIG. 1 (a), the case where the base station 110 is a base station capable of the first wireless communication 101 and the second wireless communication 102 with the mobile station 120 has been described, however, base stations 110 A and 110 B may be provided in place of the base station 110 as shown in FIG. The base station 110 A is a base station capable of performing the first wireless communication 101 with the mobile station 120. The base station 110 B is a base station connected to the base station 110 A and capable of performing the second wireless communication 102 with the mobile station 120.
[0032]
　In the example shown in FIG. 1 (b), the base station 110 A performs data transmission via the base station 110 B when performing data transmission using the second wireless communication 102 with the mobile station 120 . In this case, the control unit 111 and the processing unit 112 shown in FIG. 1 (a) are provided in the base station 110 A, for example. Further, the control unit 111 controls the second wireless communication 102 with the mobile station 120 via the base station 110 B.
[0033]
　First, the downlink that transmits data from the base station 110 A to the mobile station 120 will be described. In the downlink, the processing unit 112 of the base station 110 A makes the service quality information included in the data to be transmitted to the mobile station 120 transparent at the established convergence point and transfers the data to the base station 110 B so that the base station 110 B to the mobile station 120. The base station 110 B transmits the data transferred from the base station 110 A to the mobile station 120 by the second wireless communication 102.
[0034]
　Next, the uplink that transmits data from the mobile station 120 to the base station 110 A will be described. The processing of the processing unit 121 of the mobile station 120 is controlled by the control unit 111 of the base station 110 A. Then, the processing unit 121 makes the service quality information included in the data to the base station 110 A transparent at the established convergence point, and transmits the data to the base station 110 B by the second wireless communication 102. The base station 110B transfers the data transmitted from the mobile station 120 by the second wireless communication 102 to the base station 110A. As a result, data to the base station 110 A can be transmitted to the base station 110 A using the wireless communication 102.
[0035]
　As described above, when data is transmitted using the second wireless communication 102 under the control of the control unit 111 of the first wireless communication 101, the transmitting station of the base station 110 A and the mobile station 120 transmits the 1 makes the service quality information transparent in the processing unit of the wireless communication 101.
[0036]
　Thereby, in the downlink, the base station 110 B can perform transmission control according to the service quality information in the data transmission processing by the second wireless communication 102. In the uplink, the mobile station 120 can perform transmission control according to the service quality information in the data transmission processing by the second wireless communication 102. Therefore, it is possible to suppress degradation of communication quality by transmitting data using the second wireless communication 102, or maintain communication quality.
[0037]
　According to the first embodiment, deterioration of communication quality can be suppressed or communication quality can be maintained.
[0038]
　Next, details of the wireless communication system 100 according to Embodiment 1 shown in FIG. 1 will be described using Embodiments 2 and 3. FIG. It is needless to say that the second and third embodiments can be implemented in combination with the first embodiment, since the second and third embodiments can be regarded as embodiments embodying the first embodiment.
[0039]
Second Embodiment
　FIG. 2 is a diagram showing an example of a wireless communication system according to a second embodiment. As shown in FIG. 2, the radio communication system 200 according to the second embodiment includes a UE 211, eNBs 221 and 222, and a packet core network 230. The wireless communication system 200 is, for example, a mobile communication system such as LTE-A stipulated in 3 GPP, but the communication standard of the wireless communication system 200 is not limited thereto.
[0040]
　The packet core network 230 is, for example, an EPC (Evolved Packet Core) defined in 3 GPP, but it is not particularly limited thereto. In addition, the core network defined in 3GPP may be called SAE (System Architecture Evolution) in some cases. The packet core network 230 includes an SGW 231, a PGW 232, and an MME 233.
[0041]
　The UE 211 and the eNBs 221 and 222 form a radio access network by performing radio communication. The radio access network formed by the UE 211 and the eNBs 221 and 222 is, for example, an E-UTRAN (Evolved Universal Terrestrial Radio Access Network) defined in 3 GPP, but it is not particularly limited thereto.
[0042]
　The UE 211 is a terminal located in the cell of the eNB 221 and performing radio communication with the eNB 221. As one example, the UE 211 communicates with another communication device via a path via the eNB 221, the SGW 231, and the PGW 232. Another communication device that communicates with the UE 211 is, for example, a communication terminal different from the UE 211, a server, or the like. Communication between the UE 211 and another communication device is, for example, data communication or voice communication, but is not particularly limited thereto. Voice communication is, for example, VoLTE (Voice over LTE), but it is not particularly limited thereto.
[0043]
　The eNB 221 is a base station that forms a cell 221 a and performs radio communication with the UE 211 located in the cell 221 a. The eNB 221 relays communication between the UE 211 and the SGW 231. The eNB 222 is a base station that forms a cell 222 a and performs radio communication with UEs located in the cell 222 a. The eNB 22 relays communication between the UEs located in the cell 222 a and the SGW 231.
[0044]
　The eNB 221 and the eNB 222 may be connected by, for example, a physical or logical interface between base stations. The interface between the base stations is, for example, the X 2 interface, but the interface between the base stations is not particularly limited thereto. The eNB 221 and the SGW 231 are connected by, for example, a physical or logical interface. The interface between the eNB 221 and the SGW 231 is, for example, the S1-U interface, but it is not particularly limited thereto.
[0045]
　The SGW 231 is a serving gateway that accommodates the eNB 221 and performs U-plane (User plane) processing in communication via the eNB 221. For example, the SGW 231 performs U-plane processing in the communication of the UE 211. The U-plane is a function group for transmitting user data (packet data). In addition, the SGW 231 may accommodate the eNB 222 and perform U-plane processing in communication via the eNB 222.
[0046]
　The PGW 232 is a packet data network gateway for connecting to an external network. The external network is, for example, the Internet, but it is not limited thereto. The PGW 232, for example, relays the user data between the SGW 231 and the external network. Further, for example, the PGW 232 performs an IP address allocation 201 for assigning an IP address to the UE 211 so that the UE 211 transmits and receives the IP flow.
[0047]
　The SGW 231 and the PGW 232 are connected by, for example, a physical or logical interface. The interface between the SGW 231 and the PGW 232 is, for example, the S5 interface, but is not particularly limited thereto.
[0048]
　The MME 233 (Mobility Management Entity: Mobility Management Entity) accommodates the eNB 221 and performs processing of C-plane (control plane) in communication via the eNB 221. For example, the MME 233 performs processing of C-plane in the communication of the UE 211 via the eNB 221. The C-plane is, for example, a group of functions for controlling a call and a network between devices. As an example, the C-plane is used for connection of a packet call, setting of a route for transmitting user data, control of a handover, and the like. Further, the MME 233 may accommodate the eNB 222 and perform C-plane processing in communication via the eNB 222.
[0049]
　The MME 233 and the eNB 221 are connected by, for example, a physical or logical interface. The interface between the MME 233 and the eNB 221 is, for example, the S1-MME interface, but is not particularly limited thereto. The MME 233 and the SGW 231 are connected by, for example, a physical or logical interface. The interface between the MME 233 and the SGW 231 is, for example, the S 11 interface, but is not particularly limited thereto.
[0050]
　In the wireless communication system 200, the IP flow to be transmitted or received by the UE 211 is classified (distributed) into EPS bearers 241 to 24 n and transmitted via the PGW 232 and the SGW 231. The EPS bearers 241 to 24 n are IP flows in Evolved Packet System (EPS). The EPS bearers 241 to 24 n become radio bearers 251 to 25 n (Radio Bearer) in the radio access network formed by the UE 211 and the eNBs 221 and 222. Control of the whole communication such as setting of the EPS bearers 241 to 24 n, security setting, mobility management and the like is performed by the MME 233.
[0051]
　In the LTE network, IP flows classified as EPS bearers 241 to 24 n are transmitted by, for example, a GTP (GPRS Tunneling Protocol) tunnel set between the respective nodes. The EPS bearers 241 to 24 n are uniquely mapped to the radio bearers 251 to 25 n, respectively, and wirelessly transmitted in consideration of QoS.
[0052]
　In the communication between the UE 211 and the eNB 221 of the wireless communication system 200, aggregation is performed by LTE-A and WLAN, which offloads the traffic of LTE-A to the WLAN. As a result, the traffic between the UE 211 and the eNB 221 can be distributed to the LTE-A and the WLAN, and the throughput in the radio communication system 200 can be improved. The first wireless communication 101 shown in FIG. 1 can be, for example, wireless communication by LTE-A. The second wireless communication 102 shown in FIG. 1 can be, for example, wireless communication by WLAN. The aggregation by LTE-A and WLAN will be described later.
[0053]
　It should be noted that the designation of aggregation is an example and is often used in the sense of using a plurality of communication frequencies (carriers). Apart from aggregation, it is often referred to as integration in the sense that multiple systems are integrated and used. Hereafter, aggregation is used as a representative designation.
[0054]
　The base station 110 shown in FIG. 1 can be realized by eNBs 221 and 222, for example. The mobile station 120 shown in FIG. 1 can be realized by the UE 211, for example.
[0055]
　FIG. 3 is a diagram showing an example of the terminal according to the second embodiment. The UE 211 shown in FIG. 2 can be realized by the terminal 300 shown in FIG. 3, for example. The terminal 300 includes a wireless communication unit 310, a control unit 320, and a storage unit 330. The wireless communication unit 310 includes a wireless transmission unit 311 and a wireless reception unit 312. Each of these configurations is connected so as to be able to input and output signals and data in one direction or bidirectionally. Further, the wireless communication unit 310 can perform wireless communication (first wireless communication 101) by LTE-A, wireless communication by WLAN (second wireless communication 102), for example.
[0056]
　The radio transmission unit 311 transmits user data and a control signal by wireless communication via an antenna. The radio signal transmitted by the radio transmission unit 311 may include arbitrary user data, control information, and the like (to be encoded, modulated, etc.). The wireless reception unit 312 receives user data and control signals via wireless communication via an antenna. The radio signal received by the radio receiving unit 312 may include arbitrary user data, control signals, etc. (to be encoded, modulated, etc.). Note that the antenna may be common for transmission and reception.
[0057]
　The control unit 320 outputs user data and control signals to be transmitted to other radio stations to the radio transmission unit 311. Further, the control unit 320 acquires the user data and the control signal received by the wireless reception unit 312. The control unit 320 performs input and output of user data, control information, programs, and the like with the storage unit 330 to be described later. In addition, the control unit 320 performs input and output of user data and control signals to be exchanged with other communication devices and the like with a communication unit to be described later. The control unit 320 performs various controls in the terminal 300 besides these. The storage unit 330 stores various kinds of information such as user data, control information, and programs.
[0058]
　The processing unit 121 of the mobile station 120 shown in FIG. 1 can be realized by the control unit 320, for example.
[0059]
　FIG. 4 is a diagram showing an example of the hardware configuration of the terminal according to the second embodiment. The terminal 300 shown in FIG. 3 can be realized by the terminal 400 shown in FIG. 4, for example. The terminal 400 includes, for example, an antenna 411, an RF circuit 412, a processor 413, and a memory 414. These constituent elements are connected so that various signals and data can be inputted and outputted via a bus, for example.
[0060]
　The antenna 411 includes a transmission antenna for transmitting a radio signal and a reception antenna for receiving a radio signal. Further, the antenna 411 may be a shared antenna that transmits and receives radio signals. The RF circuit 412 performs RF (Radio Frequency) processing of a signal received by the antenna 411 and a signal transmitted by the antenna 411. The RF processing includes, for example, frequency conversion between the baseband band and the RF band.
[0061]
　The processor 413 is, for example, a CPU (Central Processing Unit), a DSP (Digital Signal Processor), or the like. Further, the processor 413 may be realized by digital electronic circuits such as ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array), LSI (Large Scale Integration).
[0062]
　The memory 414 can be realized by a RAM (Random Access Memory) such as SDRAM (Synchronous Dynamic Random Access Memory), a ROM (Read Only Memory), and a flash memory. The memory 414 stores, for example, user data, control information, programs, and the like.
[0063]
　The wireless communication unit 310 shown in FIG. 3 can be realized by, for example, the antenna 411 and the RF circuit 412. The control unit 320 shown in FIG. 3 can be realized by the processor 413, for example. The storage unit 330 shown in FIG. 3 can be realized by a memory 414, for example.
[0064]
　FIG. 5 is a diagram illustrating an example of a base station according to the second embodiment. Each of the eNBs 221 and 222 shown in FIG. 2 can be realized by the base station 500 shown in FIG. 5, for example. As shown in FIG. 5, the base station 500 includes, for example, a wireless communication unit 510, a control unit 520, a storage unit 530, and a communication unit 540. The wireless communication unit 510 includes a wireless transmission unit 511 and a wireless reception unit 512. Each of these configurations is connected so as to be able to input and output signals and data in one direction or bidirectionally. In addition, the wireless communication unit 510 can perform wireless communication (first wireless communication 101) by LTE-A, wireless communication by WLAN (second wireless communication 102), for example.
[0065]
　The radio transmission unit 511 transmits user data and a control signal by radio communication via an antenna. The radio signal transmitted by the radio transmission unit 511 may include arbitrary user data, control information, etc. (to be encoded, modulated, etc.). The wireless reception unit 512 receives user data and a control signal by wireless communication via an antenna. The radio signal received by the radio reception unit 512 may include arbitrary user data, control signals, etc. (to be encoded, modulated, etc.). Note that the antenna may be common for transmission and reception.
[0066]
　The control unit 520 outputs user data and control signals to be transmitted to other radio stations to the radio transmission unit 511. Further, the control unit 520 acquires the user data and the control signal received by the wireless reception unit 512. The control unit 520 performs input and output of user data, control information, programs, and the like with the storage unit 530 described later. Further, the control unit 520 performs input and output of user data and control signals to be exchanged with another communication device or the like with the communication unit 540 to be described later. The control unit 520 performs various controls in the base station 500 in addition to the above.
[0067]
　The storage unit 530 stores various types of information such as user data, control information, and programs. The communication unit 540 transmits and receives user data and control signals to and from other communication devices, for example, by wired signals.
[0068]
　The control unit 111 and the processing unit 112 of the base station 110 shown in FIG. 1 can be realized by the control unit 520, for example.
[0069]
　FIG. 6 is a diagram showing an example of a hardware configuration of the base station according to the second embodiment. The base station 500 shown in FIG. 5 can be realized by the base station 600 shown in FIG. 6, for example. The base station 600 includes an antenna 611, an RF circuit 612, a processor 613, a memory 614, and a network IF 615. These constituent elements are connected so that various signals and data can be inputted and outputted via a bus, for example.
[0070]
　The antenna 611 includes a transmission antenna for transmitting a radio signal and a reception antenna for receiving a radio signal. Further, the antenna 611 may be a shared antenna that transmits and receives radio signals. The RF circuit 612 performs RF processing of a signal received by the antenna 611 and a signal transmitted by the antenna 611. The RF processing includes, for example, frequency conversion between the baseband band and the RF band.
[0071]
　The processor 613 is, for example, a CPU, a DSP, or the like. Further, the processor 613 may be realized by a digital electronic circuit such as ASIC, FPGA, LSI, or the like.
[0072]
　The memory 614 can be realized by, for example, a RAM such as an SDRAM, a ROM, or a flash memory. The memory 614 stores user data, control information, programs, and the like, for example.
[0073]
　The network IF 615 is a communication interface that communicates with the network, for example, by wire. The network IF 615 may include, for example, an Xn interface for performing wired communication between base stations.
[0074]
　The radio communication unit 510 shown in FIG. 5 can be realized by the antenna 611 and the RF circuit 612, for example. The control unit 520 shown in FIG. 5 can be realized by the processor 613, for example. The storage unit 530 shown in FIG. 5 can be realized by a memory 614, for example. The communication unit 540 shown in FIG. 5 can be realized by the network IF 615, for example.
[0075]
　FIG. 7 is a diagram showing an example of a protocol stack in the wireless communication system according to the second embodiment. For example, the protocol stack 700 shown in FIG. 7 can be applied to the radio communication system 200 according to the second embodiment. The protocol stack 700 is a LTE-A protocol stack defined in 3GPP. Layer groups 701 to 705 are layer groups indicating processes in the UE 211, the eNB 221, the SGW 231, the PGW 232, and the server of the external network, respectively.
[0076]
　When the IP flow is transmitted in the radio communication system 200, the IP flow is filtered in order to perform the handling according to the QoS class for each IP flow. For the downlink where the UE 211 receives the IP flow, for example, the PGW 232 performs packet filtering on the IP flow and classifies the IP flow into the EPS bearers 241 to 24 n.
[0077]
　For the uplink in which the UE 211 transmits the IP flow, the filtering rule of the packet is notified from the PGW 232 to the UE 211. Based on the filtering rule notified from the PGW 232, the UE 211 performs packet filtering on the IP flow to classify the IP flow into the EPS bearers 241 to 24 n.
[0078]
　For example, in the uplink, the PGW 232 performs filtering of the IP flow by the filter layer 711 (Filter) included in the IP layer (IP) in the layer group 704 of the PGW 232. In the downlink, the UE 211 performs filtering of the IP flow by a filter layer 712 (Filter) included in the IP layer (IP) in the layer group 701 of the UE 211.
[0079]
　Also, in order to perform QoS control (QoS management) at the router in the LTE network, the PGW 232 (in the case of downlink) or the UE 211 (in the case of uplink) sets the QoS value in the ToS field of the header of the IP packet.
[0080]
　The packet filtering by the PGW 232 or the UE 211 is performed using, for example, 5-tuple (transmission source IP address, transmission source port number, protocol type). The filtering rule of packet filtering is called a TFT (Traffic Flow Template), for example. It should be noted that there may be EPS bearers for which no TFT is set among the EPS bearers 241 to 24 n.
[0081]
　When filtering IP flow using TFTs, IP flow can be classified into 11 types of EPS bearers at the maximum. One bearer of the EPS bearers 241 to 24 n is called a default bearer (default bearer). The default bearer is created when the PGW 232 assigns an IP address to the UE 211 and is always present until the IP address assigned to the UE 211 is released. A bearer different from the default bearer among the EPS bearers 241 to 24 n is called a dedicated bearer. Dedicated bearers can be generated and released appropriately according to the situation of the user data to be transmitted.
[0082]
　FIG. 8 is a diagram illustrating an example of layer 2 in the wireless communication system according to the second embodiment. For the wireless communication system 200 according to the second embodiment, the processing shown in FIG. 8 can be applied as a layer 2 processing as an example. The process shown in FIG. 8 is Layer 2 processing of LTE-A stipulated by 3 GPP. As shown in FIG. 8, layer 2 of LTE-A includes PDCP 810, RLC 820, and MAC 830.
[0083]
　The PDCP 810 includes ROHC (Robust Header Compression) for performing header compression of incoming IP datagrams and processing related to security. Processes related to security include confidentiality and integrity protection, for example. In normal LTE-A communication, the user data is forwarded to the lower layer (eg, layer 1) after these processes of the PDCP 810 are performed.
[0084]
　Also, for example, when implementing dual connectivity, the UE 211 can simultaneously communicate with two base stations (for example, eNBs 221 and 222) at the maximum. MCG Bearer 801 (Master Cell Group Bearer) is the radio base bearer of the main base station.
[0085]
　In addition, a split bearer 802 (Split Bearer) and an SCG bearer 803 (Secondary Cell Group Bearer) can be attached to the MCG bearer 801. In the case of using the split bearer 802, when the user data is forwarded from the layer 2 to the lower layer (for example, the layer 1), the user data is forwarded to only one base station or the user data is forwarded to the two base stations Can be selected.
[0086]
　The RLC 820 includes a primary process before wireless transmission of user data. For example, the RLC 820 includes a division of user data (Segm: SEGmentation) for adjusting the user data to a size according to the radio quality. In addition, ARQ (Automatic Repeat Request) and the like may be included in the RLC 820 for retransmission of user data that could not be corrected in the lower layer. When the user data is forwarded to the lower layer, the EPS bearer is mapped to the corresponding logical channel (Logical Channel) and wirelessly transmitted.
[0087]
　The MAC 830 includes control of wireless transmission. For example, the MAC 830 includes a process of performing packet scheduling and performing HARQ (Hybrid Automatic Repeat reQuest) of transmission data. In carrier aggregation, HARQ is performed for each carrier to be aggregated.
[0088]
　The transmitting side adds an LCID (Logical Channel Identifier) ​​to the MAC SDU (MAC Service Data Unit) which is user data in the MAC 830 and transmits the MAC SDU. The receiving side converts the radio bearer into the EPS bearer by using the LCID added by the transmitting side in the MAC 830.
[0089]
　FIG. 9 is a diagram illustrating an example of an IP header of an IP packet transmitted in the wireless communication system according to the second embodiment. In the radio communication system 200 according to the second embodiment, for example, an IP packet having an IP header 900 shown in FIG. 9 is transmitted. The IP header 900 includes, for example, a source address 901 indicating a sender and a destination address 902 indicating a destination. In addition, the IP header 900 includes a ToS field 903 for performing QoS. The above-described QoS control is performed based on the value of the ToS field 903, for example.
[0090]
　FIG. 10 is a diagram showing an example of the value of the ToS field included in the IP header of the IP packet transmitted in the wireless communication system according to the second embodiment. The "first three bits" in the table 1000 shown in FIG. 10 indicates the IP precidence corresponding to the first three bits in the ToS field 903 shown in FIG. 9 and can take 2 3 = 8 patterns. In the table 1000, eight patterns show that the higher the priority, the higher the priority of the upper pattern.
[0091]
　For example, "111" having the highest priority in the IP presence of the ToS field 903 indicates that the IP packet corresponds to the network control, and is reserved for control such as routing. Also, "110" having the second highest priority in the IP precessence of the ToS field 903 indicates that the IP packet corresponds to the Internet control, and is reserved for control such as routing.
[0092]
　In the example shown in FIG. 10, the case where the IP presence of the ToS field 903 is used as the priority information of the QoS has been described. However, the priority information of the QoS is not limited thereto, and for example, using the DSCP (Differentiated Services Code Point) field It is also good. DSCP is a field corresponding to the first 6 bits in the ToS field 903.
[0093]
　FIG. 11 is a diagram showing an example of aggregation by LTE-A and WLAN in the wireless communication system according to the second embodiment. Layer 2 processing in aggregation by LTE-A and WLAN is based on the processing of dual connectivity described above taking into consideration the backward compatibility of LTE-A, for example.
[0094]
　The IP flow 1101 is an IP flow based on HTTP (Hypertext Transfer Protocol) between the UE 211 and the eNB 221. The IP flow 1102 is an IP flow based on FTP (File Transfer Protocol) between the UE 211 and the eNB 221.
[0095]
　The on-load processing 1111 shows the processing in the case of transmitting the IP flows 1101 and 1102 by LTE-A without offloading to the WLAN. The on-load processing 1111 corresponds to the transmission of data using the wireless communication by the first wireless communication 101 shown in FIG. 1. In the on-load process 1111, processing is performed in the order of PDCP, RLC, LTE-MAC, and LTE-PHY for each of the IP flows 1101 and 1102. The PDCP, the RLC, and the LTE-MAC are, for example, the PDCP 810, the RLC 820, and the MAC 830 shown in FIG. 8, respectively. LTE-PHY is a physical layer in LTE-A.
[0096]
　Offload processing 1112 shows processing in the case of offloading the IP flows 1101, 1102 to the WLAN for transmission. This offload processing 1112 corresponds to transmission of data using wireless communication by the second wireless communication 102 shown in FIG. 1. In the offload processing 1112, with respect to the IP flows 1101 and 1102, PDCP TM,. 11 x MAC,. 11 × PHY in this order. . 11 x MAC,. The 11x PHY is the MAC layer and the PHY layer in the WLAN (802.11x), respectively.
[0097]
　In LTE-A, IP flows are classified as bearers and managed as bearers. On the other hand, in 802.11x of IEEE (Institute of Electrical and Electronics Engineers) which is one example of WLAN, the IP flow is managed as IP flow instead of bearer. Therefore, it is required to manage the mapping of which bearer belongs to which L2 layer, like the mapping management 1120, and to perform the on-load processing 1111 and the offload processing 1112 at high speed.
[0098]
　Mapping management 1120 is performed, for example, by RRC which performs radio control between UE 211 and eNB 221. By managing the radio bearer, the RRC manages the on-load processing 1111 using the wireless communication by the LTE-A (the first wireless communication 101), the offload processing 1112 using the wireless communication by the WLAN (the second wireless communication 102) At the radio bearer level. In the example shown in FIG. 11, IP flow 1101 with IP flow ID = 0 in HTTP is managed as a bearer with bearer ID = 0, IP flow 1102 with FTP IP flow ID = 0 is managed as a bearer with bearer ID = 1 ing.
[0099]
　Further, in the offload processing 1112, the wireless communication system 200 according to the second embodiment sets the PDCP in the LTE-A to the transparent mode (TM) in order to enable support of the WLAN QoS in the offload processing 1112 . As a result, the IP flows 1101 and 1102 are offloaded to the WLAN without performing processes such as concealment (encryption), header compression, addition of a sequence number, and the like.
[0100]
　Therefore, in the WLAN, it becomes possible to refer to the ToS field included in the offloaded IP flows 1101, 1102. For example, in QoS in IEEE802.11e, QoS is managed by consolidating IP flows into four types of AC (Access Category) with reference to the ToS field etc. of the IP header. In the wireless communication system 200, it is possible to perform QoS processing based on the ToS field by referring to the ToS field included in the offloaded IP flows 1101 and 1102 in the WLAN.
[0101]
　In the offload processing 1112, the user data transferred to the WLAN is subjected to an anonymization process in the WLAN, for example. Therefore, even when the user data is transferred to the WLAN without performing the concealment processing by the PDCP, it is possible to avoid the user data being transmitted between the eNB 221 and the UE 211 without being concealed.
[0102]
　For concealing the WLAN, for example, AES (Advanced Encryption Standard), TKIP (Temporal Key Integrity Protocol), WEP (Wired Equivalent Privacy), or the like can be used.
[0103]
　In the example shown in FIG. 11, the case where PDCP is set as the convergence point (branch point) and the IP flows 1101 and 1102 do not pass through the RLC and LTE-MAC when performing the offload processing 1112 has been described, It is not limited to processing. For example, when offload processing 1112 is performed, RLC and LTE-MAC, which are lower layers of PDCP, are set as convergence points (branch points), and IP flows 1101 and 1102 pass through RLC and LTE-MAC as well as PDCP As shown in FIG. In this manner, the processor that establishes the convergence point (branch point) when performing offload to the WLAN is not limited to the PDCP processing unit, and may be a processing unit of RLC or LTE-MAC.
[0104]
　The data link layer (layer 2) such as PDCP, RLC, LTE-MAC, etc. can grasp the congestion state of communication in the radio section between the UE 211 and the eNB 221. Therefore, by establishing the convergence point in the data link layer and performing offload to the WLAN, it is possible to determine whether or not to perform offload to the WLAN according to the congestion state of the communication in the radio section between the UE 211 and the eNB 221 Etc. can be determined.
[0105]
　FIG. 12 is a diagram illustrating an example of QoS control based on the ToS field in the wireless communication system according to the second embodiment. For example, the case where the eNB 221 has the function of WLAN communication and the eNB 221 transmits the IP packet 1201 to the UE 211 will be described. Based on the ToS field in the IP header of the IP packet 1201, the eNB 221 classifies the IP packet 1201 into AC 1211 to 1214 of voice, video, best effort, or background.
[0106]
　In the wireless communication system 200 according to the second embodiment, when offloading to the WLAN is performed, the PDCP in the LTE-A becomes the transparent mode, and the IP packet 1201 is offloaded to the WLAN without being secret or the like . Therefore, even in WLAN processing, the eNB 221 can refer to the ToS field of the IP packet 1201 and perform AC classification based on the ToS field.
[0107]
　The case where the eNB 221 has the function of the WLAN communication has been described, but the same applies to the case where the eNB 221 performs the offload to the WLAN by transmitting the IP flow to the access point of the WLAN. Also, the case where the IP packet 1201 is transmitted from the eNB 221 to the UE 211 (downlink) has been described, but the same applies to the case (IPLP) of transmitting the IP packet 1201 from the UE 211 to the eNB 221.
[0108]
　FIG. 13 is a diagram showing an example of AC classification in the wireless communication system according to the second embodiment. In FIG. 13, parts similar to those shown in FIG. 12 are denoted by the same reference numerals, and description thereof is omitted.
[0109]
　In FIG. 13, the case where eNB 221 has the function of WLAN communication and eNB 221 transmits IP packets 1301 and 1302 to UE 211 will be described. IP packets 1301 and 1302 are IP packets of HTTP and FTP, respectively.
[0110]
　The eNB 221 performs ToS value analysis classification 1310 that classifies the IP packets 1301 and 1302 into one of ACs 1211 to 1214 based on the value of the ToS field included in the IP header. In the example shown in FIG. 13, the eNB 221 classifies the IP packet 1301 into AC 1213 (best effort) and classifies the IP packet 1302 into AC 1214 (background). Then, the eNB 221 transmits the IP packets 1301 and 1302 for which the ToS value analysis classification 1310 has been performed to the UE 211 via the WLAN.
[0111]
　In the mapping management 1320 by RRC between the eNB 221 and the UE 211, the HTTP IP packet 1301 is managed with IP flow ID = AC = 2 and bearer ID = 0. AC = 2 indicates AC 1213 (best effort). Further, in the mapping management 1320, the FTP IP packet 1302 is managed with IP flow ID = AC = 3 and bearer ID = 1. AC = 3 indicates AC 1214 (background).
[0112]
　The UE 211 terminates the IP packets 1301 and 1302 in the PDCP (transparent mode) by performing the ToS value analysis classification 1330 (de-classification) corresponding to the ToS value analysis classification 1310 (classification) on the side of the eNB 221 .
[0113]
　The case of transmitting the IP packets 1301 and 1302 from the eNB 221 to the UE 211 (downlink) has been described, but the same applies to the case (IPLP) of transmitting the IP packets 1301 and 1302 from the UE 211 to the eNB 221.
[0114]
　FIG. 14 is a diagram showing an example of offload in the wireless communication system according to the second embodiment. In FIG. 14, the case where the eNB 221 is the master eNB and the WLAN independent configuration using the secondary eNB 223 having the eNB and WLAN communication functions (eNB + WLAN) is performed on the WLAN will be described with reference to FIG. 14. Offload to the WLAN is the transmission of data using the second wireless communication 102 shown in FIG. The secondary eNB 223 is a base station capable of communicating with the eNB 221 through an interface between base stations such as an X 2 interface and capable of communicating with the UE 211 in the WLAN.
[0115]
　In the example shown in FIG. 14, ten EPS bearers 1400 to 140 n are set between the eNB 221 and the UE 211 for communication, and the case where the EPS bearers 1400 to 140 n are offloaded to the WLAN will be described. In the example shown in FIG. 14, the EPS bearers 1400 to 140 n are bearers in the downward direction from the eNB 221 to the UE 211. However, in FIG. 14, the case where ten EPS bearers 1400 to 140 n are set will be described, but the number of EPS bearers to be set is arbitrary.
[0116]
　The EPS bearers 1400 to 140 n are n + 1 EPS bearers with EBI (EPS Bearer ID) of 0 to n (n is, for example, 10). Both the sender (src IP) of the EPS bearers 1400 to 140 n are the core network (CN). Both destinations (dst IP) of EPS bearers 1400 to 140 n are UE 211 (UE).
[0117]
　When offloading the EPS bearers 1400 to 140 n to the WLAN, the eNB 221 transfers the EPS bearers 1400 to 140 n to the secondary eNB 223 via the PDCP layers 1410 to 141 n, respectively. That is, the eNB 221 controls offloading of the EPS bearers 1400 to 140 n to the WLAN by LTE-A layer 2 (PDCP in the example shown in FIG. 14).
[0118]
　At this time, the eNB 221 sets the PDCP layers 1410 to 141 n in the transparent mode (PDCP TM), thereby preventing processing such as PDCP concealment, header compression, and the like from being performed on the EPS bearers 1400 to 140 n. As a result, the EPS bearers 1400 to 140 n are offloaded to the secondary eNB 223 while maintaining the PDCP SDU (PDCP Service Data Unit). That is, the EPS bearers 1400 to 140 n are offloaded to the WLAN without performing processing such as concealment, header compression or the like on the IP header including the ToS field, in which the ToS field (QoS information) is transparent. PDCP SDU is equivalent to IP datagram.
[0119]
　The EPS bearers 1400 to 140 n can be transferred from the eNB 221 to the secondary eNB 223 in the same manner as the LTE-A handover, for example. For example, the transfer of the EPS bearers 1400 to 140 n from the eNB 221 to the secondary eNB 223 can be performed using the GTP tunnels 1420 to 142 n between the eNB 221 and the secondary eNB 223. The GTP tunnels 1420 to 142 n are GTP tunnels set for each EPS bearer between the eNB 221 and the secondary eNB 223.
[0120]
　The secondary eNB 223 receives the EPS bearers 1400 to 140 n transferred from the eNB 221 via the GTP tunnels 1420 to 142 n by the PDCP layers 1430 to 143 n, respectively. Then, the secondary eNB 223 performs AC classification 1440 based on the ToS field included in the IP header of the PDCP SDU for each PDCP SDU corresponding to the received EPS bearers 1400 to 140 n.
[0121]
　The AC classification 1440 is processing by the function of the WLAN (802.11e) in the secondary eNB 223. By AC classification 1440, as shown in FIG. 12, for example, each PDCP SDU is classified as AC of any of Voice (VO), Video (VI), Best Effort (BE), and Background (BK) .
[0122]
　The secondary eNB 223 transmits each PDCP SDU classified by the AC classification 1440 to the UE 211 via the WLAN 1450. In this case, the SSID (Service Set Identifier) ​​in the WLAN 1450 may be "offload", for example.
[0123]
　For each PDCP SDU received via the WLAN 1450, the UE 211 performs AC declaration 1460 based on the ToS field included in the IP header of the PDCP SDU. The AC declaration 1460 is processing by the function of the WLAN (802.11 e) in the UE 211.
[0124]
　The UE 211 reclassifies each PDCP SDU received by the AC declaration 1460 into EPS bearers 1400 to 140 n based on the classified ACs. Then, the UE 211 processes and re-classifies the re-classified EPS bearers 1400 to 140 n by the PDCP layers 1470 to 147 n.
[0125]
　At this time, the PDCP layers 1410 to 141 n in the eNB 221 are in the transparent mode, and processing such as PDCP concealment and header compression is not performed for the EPS bearers 1400 to 140 n. Therefore, the UE 211 sets the PDCP layers 1470 to 147 n in the UE 211 to the transparent mode (PDCP TM) so as not to perform decryption for privacy or header decompression for header compression.
[0126]
　In this manner, in the radio communication system 200, when offloading the EPS bearers 1400 to 140 n to the WLAN 1450, the PDCP layers 1410 to 141 n of the eNB 221 can be set to the transparent mode. As a result, the ToS field included in the IP header of each PDCP SDU can be referred to in the off-road destination secondary eNB 223. Therefore, when offloading the EPS bearers 1400 to 140 n to the WLAN 1450, AC classification 1440 based on the ToS field can be performed to perform QoS control according to traffic characteristics.
[0127]
　As an example, when offloading the EPS bearer of VoLTE to the WLAN 1450, by classifying the EPS bearer as voice (VO) and transmitting it preferentially by the WLAN 1450, the communication quality of VoLTE can be improved.
[0128]
　In the WLAN 1450, it is also possible to perform AC classification by referring to the priority value in the VLAN tag defined by IEEE 802.1q. The VLAN tag is an identifier of the VLAN.
[0129]
　Further, by setting the PDCP on the LTE-A side to the transparent mode to avoid concealment or the like, even without changing the existing chip relating to the PHY layer and the MAC layer in the WLAN, QoS control becomes possible.
[0130]
　In FIG. 14, the case where the eNB 221 becomes the master eNB and the WLAN independent configuration using the secondary eNB 223 having the eNB and WLAN communication functions (eNB + WLAN) performs the offload to the WLAN has been described. However, offloading to the WLAN is not limited to this, and offloading to the WLAN may be performed in the configuration where the eNB 221 also has the function of WLAN communication (eNB + WLAN), for example. In this case, the eNB 221 does not need to use the secondary eNB 223 for communication with the UE 211 by the WLAN.
[0131]
　In addition, in the case of transmitting user data on-line using LTE-A without offloading to the WLAN, that is, in the case of transmitting user data by using the first wireless communication 101 shown in FIG. 1 , It is not necessary to use the secondary eNB 223. In this case, for example, the eNB 221 sets the PDCP layers 1410 to 141 n to the non-transparent mode in which PDCP processing such as concealment is performed. Then, the eNB 221 processes the EPS bearers 1400 to 140 n processed by the non-transparent mode PDCP layers 1410 to 141 n in the order of RLC, MAC, and PHY, and wirelessly transmits the EPS bearers 1400 to 140 n to the UE 211 by LTE-A. The UE 211 receives the EPS bearers 1400 to 140 n transmitted from the eNB 221 by the LTE-A by processing them by PHY, MAC, RLC, and PDCP (PDCP layers 1470 to 147 n). In this case, the UE 211 sets the PDCP layers 1470 to 147 n to non-transparent mode for performing PDCP processing such as decryption corresponding to concealment.
[0132]
　FIG. 15 is a diagram showing an example of the mapping of the QoS class to AC applicable to the wireless communication system according to the second embodiment. The transmitting side (for example, the secondary eNB 223) of the WLAN classifies the EPS bearer to be transmitted into AC as shown in a table 1500 of FIG. 15, for example. For example, the QoS class of the EPS bearer is identified by QCI (QoS Class Identifier).
[0133]
　Each QCI is classified into four ACs: Voice (VO), Video (VI), Best Effort (BE), and Background (BK). The receiving side of the WLAN (eg UE 211) performs the conversion from AC to QoS class. Therefore, the eNB 221 presets the EPS bearer to be offloaded in the UE 211 in advance. On the other hand, for example, in the downlink, the UE 211 can specify the EPS bearer based on the EPS bearer set from the eNB 221. Also, in the uplink, the UE 211 can perform AC classification based on the EPS bearer set from the eNB 221.
[0134]
　FIG. 16 is a flowchart showing an example of processing by the transmission-side apparatus in the radio communication system according to the second embodiment. In FIG. 16, a downlink case in which user data is transmitted from the eNB 221 to the UE 211 will be described.
[0135]
　First, the eNB 221 judges whether to offload the user data to the UE 211 to the WLAN (step S 1601). The determination method in step S1601 will be described later.
[0136]
　If it is determined in step S1601 that no offload is to be executed (step S1601: No), the eNB 221 sets the PDCP layer of its own station to the non-transparent mode (step S1602). The non-transparent mode is a normal mode of the PDCP layer that performs processing such as PDCP hiding and header compression on the user data. In step S1602, the eNB 221 may control the UE 211 so as to set the PDCP layer of the UE 211 to the non-transparent mode according to the PDCP layer of the eNB 221 itself.
[0137]
　Next, the eNB 221 transmits the user data to the UE 211 by the LTE-A (step S 1603), and ends the series of processing. Since the PDCP layer of the eNB 221 is set to the non-transparent mode in step S1602, in step S1603, user data on which concealment of PDCP, header compression, etc., has been performed is transmitted. On the other hand, the UE 211 can receive the user data transmitted from the eNB 221 by performing processing such as decryption for privacy and header decompression for header compression in the PDCP layer.
[0138]
　If it is determined in step S1601 that offload is to be executed (step S1601: Yes), the eNB 221 sets the PDCP layer of its own station to the transparent mode (step S1604). In step S1604, the eNB 221 may control the UE 211 to set the PDCP layer of the UE 211 to the transparent mode according to the PDCP layer of the eNB 221 itself.
[0139]
　Next, the eNB 221 transmits the user data to the UE 211 via the WLAN (step S 1605), and ends the series of processing. For example, when the eNB 221 has the function of WLAN communication, the eNB 221 transmits the user data to the UE 211 by the function of the WLAN communication of its own station. On the other hand, when the eNB 221 does not have the function of the WLAN communication, the eNB 221 transfers the user data to the UE 211 to the secondary eNB 223 having the function of the WLAN communication connected to the eNB 221 so as to transmit the user data .
[0140]
　Also, since the PDCP layer of the eNB 221 is set to the transparent mode in step S1604, in step S1605, user data is transmitted without concealing PDCP concealment, header compression, or the like. Therefore, QoS control based on ToS field becomes possible in WLAN.
[0141]
　The determination in step S1601 described above can be made based on whether or not it is instructed from the UE 211 or the network side (for example, the PGW 232) to offload the user data of the UE 211 to the WLAN. Alternatively, the determination in step S1601 can be made, for example, based on whether the amount of user data to the UE 211 has exceeded the threshold. The amount of user data may be an amount per time or may be a total amount of a series of user data of the UE 211. Alternatively, the determination in step S1601 can be made based on, for example, the delay time of communication by the LTE-A between the eNB 221 and the UE 211, the delay time of the communication by the WLAN between the eNB 221 and the UE 211, and the like.
[0142]
　In FIG. 16, processing by the eNB 221 in the downlink case of transmitting the user data from the eNB 221 to the UE 211 has been described, but processing by the UE 211 in the case of uplink in which the user data is transmitted from the UE 211 to the eNB 221 is similar. However, the process in step S 1605 differs depending on whether the eNB 221 has the function of WLAN communication or not. When the eNB 221 has the function of WLAN communication, the UE 211 directly transmits the user data to the eNB 221 to the eNB 221. On the other hand, when the eNB 221 does not have the function of the WLAN communication, the UE 211 transfers the user data to the eNB 221 to the secondary eNB 223 having the function of the WLAN communication connected to the eNB 221 to transfer the user data to the eNB 221 Send.
[0143]
　FIG. 17 is a diagram showing an example of a case where a plurality of EPS bearers have the same QoS class in the radio communication system according to the second embodiment. In FIG. 17, parts similar to those shown in FIG. 13 are denoted by the same reference numerals, and description thereof is omitted. For example, when the IP packets 1301 and 1302 are both IP packets in the background, in the ToS value analysis classification 1310, both the IP packets 1301 and 1302 are classified as AC 1214 (background).
[0144]
　In this case, in the mapping management 1320 in the RRC between the UE 211 and the eNB 221, the HTTP IP packet 1301 is managed with IP flow ID = AC = 3 and bearer ID = 0. Further, in the mapping management 1320, the FTP IP packet 1302 is managed with IP flow ID = AC = 3 and bearer ID = 1.
[0145]
　In this case, even if the ToS value analysis classification 1330 corresponding to the ToS value analysis classification 1310 is performed, the UE 211 determines which of the received IP packets 1301, 1302 is an EPS bearer with bearer ID = 0, 1 Can not be determined based on AC.
[0146]
　Also, when sending user data via WLAN, it is not possible to add LCID to IP datagram (PDCP SDU). Therefore, the eNB 221 can not determine which one of the received EPS bearers with bearer ID = 0 or 1, based on the LCID, of each of the received IP packets 1301 and 1302.
[0147]
　In this way, when a plurality of EPS bearers have the same QoS class, the receiving side (the UE 211 in the example shown in FIG. 17) may not be able to uniquely identify the EPS bearer. That is, the receiving side may not be able to convert the received radio bearer into an EPS bearer. Particularly, in the uplink, since the IP flow between the eNB 221 and the PGW 232 is managed as an EPS bearer, when the eNB 221 can not convert the radio bearer into the EPS bearer, it becomes difficult to transmit the IP flow from the eNB 221 to the PGW 232.
[0148]
　On the other hand, in the radio communication system 200 according to the second embodiment, for example, the transmitting side of the UE 211 and the eNB 221 does not offload the EPS bearers having the same QoS class at the same time.
[0149]
　For example, when sending a plurality of EPS bearers having the same QoS class to the UE 211, the sending side offloads only one of the plurality of EPS bearers to the WLAN, and the remaining EPS bearers are off to the WLAN And transmits it to the UE 211 without loading. Alternatively, when transmitting a plurality of EPS bearers having the same QoS class to the UE 211, the transmitting side performs transmission by LTE-A without performing offloading to the WLAN. As a result, since a plurality of EPS bearers having the same QoS class are not offloaded to the WLAN at the same time, the UE 211 can uniquely specify the EPS bearer based on the AC for each user data offloaded to the WLAN.
[0150]
　Alternatively, on the transmitting side of the UE 211 and the eNB 221, when transmitting a plurality of EPS bearers having the same QoS class to the UE 211, the transmitting side may perform a process of aggregating the plurality of EPS bearers into one bearer. For processing of aggregating a plurality of EPS bearers into one bearer, for example, "UE requested bearer resource modification procedure" defined in TS 23.401 of 3 GPP can be used. As a result, since a plurality of EPS bearers having the same QoS class are not offloaded to the WLAN at the same time, the UE 211 can uniquely specify the EPS bearer based on the AC for each user data offloaded to the WLAN.

The scope of the claims

[Claim 1]
　A base station that controls a second radio communication different from the first radio communication by a control unit that controls a first radio communication; and a control unit that controls
　the second radio communication by using the first radio communication or the second radio communication, And a mobile station capable of
　performing data transmission between the base station and the mobile station, wherein, when transmitting data using the second wireless communication between the base station and the mobile station, the base station and the mobile station , The processing unit for performing the first wireless communication in the station on the transmitting side establishes a convergence point for performing the first wireless communication and at the convergence point, the service quality included in the data And transmits the data to a station on the receiving side out of the base station and the mobile station
　.
[Claim 2]
　The processing unit for performing the first wireless communication in the station on the transmitting side
　may use the first wireless communication without using the second wireless communication between the base station and the mobile station When data is transmitted, processing including at least one of an anonymity, a header compression, and a sequence number addition is performed on the data,
　and the second wireless communication between the base station and the mobile station , A process including at least one of the concealment, header compression, and addition of a sequence number is not performed on the data when the data is transmitted using
　the radio Communication system.
[Claim 3]
　The processing unit for performing the first wireless communication in the station on the transmitting side aggregates a plurality of bearers between the base station and the mobile station at the convergence point and transmits the bearers to the receiving side And transmits said data to said station.
[Claim 4]
　Wherein the control unit uses each of a plurality of bearers between the base station and the mobile station, the plurality of bearers having the same service class indicated by the service quality information using the second wireless communication And controls the transmission of the data to the station on the receiving side so as not to transmit the data at the same time.
[Claim 5]
　When transmitting data from the base station to the mobile station using the second wireless communication, the mobile station transmits data received using the second wireless communication to the base station and the mobile station And processes the bearer corresponding to the data among the bearers of the first wireless communication between the first wireless communication and the second wireless communication without identifying a bearer corresponding to the data.
[Claim 6]
　When data is transmitted from the mobile station to the base station using the second wireless communication, the base station transmits the data received using the second wireless communication from the mobile station Performing bearer corresponding to the received data among the bearers of the first wireless communication between the base station and the mobile station by performing packet filtering using the filtering rule in the uplink to the base station 6. The wireless communication system according to claim 1, wherein the wireless communication system further comprises:
[7]
　When transmitting data from the base station to the mobile station by using the second wireless communication, the mobile station transmits the data received using the second wireless communication from the base station By performing packet filtering using a filtering rule in a downlink to a mobile station, a bearer corresponding to the received data among the bearers of the first wireless communication between the base station and the mobile station Wherein the wireless communication system identifies the wireless communication system based on the identification information.
[Claim 8]
　When data is transmitted between the base station and the mobile station by using the second wireless communication,
　the station on the transmission side transmits the data of the second base station, which is set between the base station and the mobile station ,
　The station on the receiving side transmits the data according to the virtual data flow of the wireless communication between the base station and the mobile station by the destination address of the virtual data flow that has received the data And identifies a bearer corresponding to the received data among the bearers of the communication, based on the received data
　.
[Claim 9]
　When data is transmitted between the base station and the mobile station by using the second wireless communication,
　the station on the transmission side transmits the data of the second base station, which is set between the base station and the mobile station ,
　The station on the receiving side transmits the data according to the identifier of the virtual local area communication network which has received the data, and the station on the receiving side transmits the first data between the base station and the mobile station Wherein the bearer identification unit identifies a bearer corresponding to the received data among the bearers of
　the wireless communication.
[Claim 10]
　When data is transmitted between the base station and the mobile station by using the second wireless communication,
　the station on the transmission side transmits the data of the second base station, which is set between the base station and the mobile station ,
　The station on the receiving side transmits the data according to the destination address of the encapsulated tunnel that has received the data and transmits the data through the encapsulated tunnel of the first radio And identifies a bearer corresponding to the received data among the bearers of the communication, based on the received data
　.
[Claim 11]
　When transmitting data using the second wireless communication between the base station and the mobile station, the base station and the mobile station transmit the data of the first wireless communication Setting the communication path of the second wireless communication between the base station and the mobile station, and transmitting the data according to the set communication path. Radio communication system.
[Claim 12]
　12. The radio communication system according to any one of claims 1 to 11, wherein transmission control based on the service quality information is performed in the second radio communication.
[Claim 13]
　A base station capable of data transmission with a mobile station by using a first radio communication or a second radio communication different from the first radio communication, the base station
　comprising: a first radio communication and a second radio communication ,
　A processing unit for performing the first wireless communication, wherein when transmitting data from the base station to the mobile station by using the second wireless communication, the first wireless communication is performed on the first and of establishing a convergence point for wireless communication, in the convergence point, and a processing unit for transmitting the data to the mobile station in the transmission quality of service information contained in the data
　, characterized in that it comprises a base station.
[Claim 14]
　Using a first wireless communication or a second wireless communication with a base station that controls a second wireless communication different from the first wireless communication by a control unit that controls first wireless communication A mobile station capable of data transmission,
　comprising: a processing unit for performing the first wireless communication, wherein when transmitting data from the mobile station to the base station using the second wireless communication to establish a convergence point for performing the first wireless communication, at the convergence point, and the transmission quality of service information contained in the data comprising a processing unit for transmitting the data to the base station,
　that Featured mobile stations.