WO2013021526A1 - Station de relais, station de base, système de télécommunication mobile, procédé de commande de liaison de raccordement et support lisible par un ordinateur - Google Patents

Station de relais, station de base, système de télécommunication mobile, procédé de commande de liaison de raccordement et support lisible par un ordinateur Download PDF

Info

Publication number
WO2013021526A1
WO2013021526A1 PCT/JP2012/003037 JP2012003037W WO2013021526A1 WO 2013021526 A1 WO2013021526 A1 WO 2013021526A1 JP 2012003037 W JP2012003037 W JP 2012003037W WO 2013021526 A1 WO2013021526 A1 WO 2013021526A1
Authority
WO
WIPO (PCT)
Prior art keywords
backhaul link
frequency
band frequency
relay station
switching
Prior art date
Application number
PCT/JP2012/003037
Other languages
English (en)
Japanese (ja)
Inventor
洋明 網中
義一 鹿倉
Original Assignee
日本電気株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日本電気株式会社 filed Critical 日本電気株式会社
Priority to JP2013527843A priority Critical patent/JP6065835B2/ja
Publication of WO2013021526A1 publication Critical patent/WO2013021526A1/fr

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
    • H04W84/04—Large scale networks; Deep hierarchical networks
    • H04W84/042—Public Land Mobile systems, e.g. cellular systems
    • H04W84/047—Public Land Mobile systems, e.g. cellular systems using dedicated repeater stations
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W92/00—Interfaces specially adapted for wireless communication networks
    • H04W92/16—Interfaces between hierarchically similar devices
    • H04W92/20—Interfaces between hierarchically similar devices between access points

Definitions

  • the present invention relates to a mobile communication system including a base station and a relay station belonging to the base station, and more particularly to control of a frequency used for a backhaul link connecting the base station and the relay station.
  • RN Relay node
  • UE User Equipment
  • eNB Evolved Node B
  • FIG. 1 is a diagram illustrating an example of a network configuration when using RN, which is being studied in 3GPP.
  • a base station (eNB) 91 belongs to a core network (hereinafter referred to as CN) 4 of a mobile communication carrier.
  • the base station (eNB) 91 generates an eNB cell 10 and relays traffic between the mobile station (UE) 3-1 and the core network (CN) 4.
  • the relay station (RN) 92 belongs to the base station (eNB) 91 via the backhaul link (BL1 in the figure), and belongs to the core network (CN) 4 via the backhaul link (BL1).
  • the relay station (RN) 2 can be connected to the management device 5 via the core network (CN) 4.
  • the management device 5 is an OAM (Operation Administration and Maintenance) system and manages information set by a mobile communication carrier.
  • the relay station (RN) 2 can acquire information from the management device 5.
  • the mobile stations (UE) 3-1 and 3-2 belong to the base station (eNB) 91 or the relay station (RN) 92 through an access link (AL1 or AL2 in the figure).
  • the relay station (RN) 92 generates the RN cell 20 and relays traffic between the mobile station (UE) 3-2 and the core network (CN) 4. The backhaul link and access link will be described later.
  • Fig. 2 is a sequence diagram showing an outline of the RN startup procedure described in Section 4.7.6 of Non-Patent Document 3.
  • the RN startup procedure includes Phase 1 and Phase 2 described below.
  • the relay station (RN) 92 is connected to the network (E-UTRAN / EPC) as a mobile station (UE) in the same procedure as a normal mobile station (UE) (steps S9002 and S9003).
  • the relay station (RN) 92 acquires initial setting parameters from the management device 5 (i.e. OAM system) (step S9004).
  • the management device 5 i.e. OAM system
  • the initial setting parameters include a list of eNB cells (donor cell list) that can be assigned as an RN using the backhaul link (BL1).
  • the relay station (RN) 92 ends phase 1 by releasing the network connection as the UE (step S9005). Note that the base station (eNB) 91-1 to which the relay station (RN) 92 belongs in phase 1 may not have a function of receiving the attribution of the relay station (RN).
  • the relay station (RN) 92 selects one cell from at least one eNB cell (donor cell candidate) included in the donor cell list acquired from the management apparatus 5, and manages the selected cell. It belongs to the station (eNB) 91-2 as the relay station (RN) 2 (steps S9006 and S9007). Then, the relay station (RN) 92 acquires the setting information of the backhaul link (BL1) from the base station (eNB) 91 to which it belongs, and sets the backhaul link (BL) (step S9008). After completion of the phase 2 procedure, the relay station (RN) 92 starts operation of the relay station cell (RN cell) 20 (step S9009).
  • Non-Patent Document 4 there are three types of RNs that are being studied by 3GPP: Type 1, Type 1a, and Type 1b.
  • the RN may support only one of these three types, may change the operation mode among a plurality of types, or may use a different operation mode between UEs.
  • the type 1 RN uses the same frequency for the backhaul link and the access link, and time-divides the radio resource for the backhaul link and the radio resource for the access link. This is mainly intended to avoid interference from transmission of the access link at the RN to reception of the backhaul link.
  • the RN operation mode using the same frequency for the bankhole link and the access link is called in-band (or inband) operation.
  • Type 1a RNs use different frequencies for the backhaul link and access link. Therefore, type 1a RNs do not require time sharing of radio resources like type 1 RNs, and perform independent communication between the backhaul link and the access link.
  • the operation mode of RN that uses different frequencies for the backhaul link and the access link is called out-band (or outband, out-of-band) operation.
  • Type 1b RN like Type 1 RN, performs in-band operation using the same frequency on the backhaul link and access link. However, type 1b RNs do not perform time division of radio resources. When this type is used, it is assumed that the interference to the reception of the backhaul link due to the transmission of the access link can be separated and suppressed.
  • RN transmits RN identification information including RN type to eNB in phase 2 of the startup procedure described above. And eNB determines the control method of a backhaul link based on RN type information contained in RN identification information. More specifically, the eNB determines whether to perform in-band operation or out-band operation and whether to time-divide radio resources of the backhaul link based on the RN type information.
  • Donor eNB an eNB that accepts RN attribution is referred to as “Donor eNB (hereinafter DeNB)”.
  • a mobile station (UE) directly belonging to a relay station (RN) is referred to as “RN-UE”.
  • a mobile station (UE) directly belonging to a donor base station (DeNB) is referred to as “eNB-UE”.
  • Multi-hop RN is a technology that enables cascade connection of relay stations (RN) to relay stations (RN) belonging to the eNB.
  • the relay station (RN) belonging to the lower layer of the eNB with the radio interface is called ⁇ upper RN '', and the relay station belonging to the lower layer of the upper RN with the radio interface ( RN) is referred to as “lower RN” for distinction.
  • a radio interface between the eNB and the RN and between the upper RN and the lower RN is referred to as a “backhaul link”.
  • a radio interface between the eNB and the eNB-UE, and between the RN and the RN-UE is referred to as an “access link”.
  • 3GPP TR 36.912 V9.2.0 (2010-03), "Feasibility study for Further Advancements for E-UTRA (LTE-Advanced)", 3GPP (3rdGeneration Partnership Project), 2010 3GPP TR 36.806 V9.0.0 (2010-03), "Relay architectures for E-UTRA (LTE-Advanced)", 3GPP, March 2010 3GPP TS 36.300 V10.1.0 (2010-09), “Overall description; Stage 2 (Release 10)", 3GPP, October 2010 3GPP TR 36.814 V9.0.0 (2010-03), "Further advancements for E-UTRA physical layer aspects", 3GPP, March 2010
  • the inventors of the present application conducted a detailed study on the method of switching the frequency used for the RN backhaul link. Whether or not to use the same frequency as the access link for the backhaul link, in other words, whether to use in-band operation or out-band operation, generally depends on the load on the RN cell (eg RN cell traffic volume). It is thought that it is decided based on. Furthermore, as described with reference to the sequence diagram of FIG. 2, whether to perform in-band operation or out-band operation is determined at the initial setup of the RN. Therefore, for example, it is considered that the backhaul link is set so as to be able to cope with the maximum value of the assumed load of the RN cell at the time of initial setup of the RN.
  • the frequency utilization efficiency may decrease.
  • the DeNB operates the access link (AL1) with the eNB-UE at the first frequency and operates the backhaul link (BL1) with the RN for out-band operation at the second frequency.
  • AL1 access link
  • BL1 backhaul link
  • the time zone when the number of UEs connected to the DeNB and the RN is small and the traffic volume to be handled by the DeNB and the RN is small, it is assumed that the utilization rates of the first and second frequencies are low.
  • the frequency utilization efficiency decreases. It is not preferable to always use the first and second frequencies corresponding to the maximum load from the viewpoint of generating wasteful power consumption.
  • One of the objects of the present invention is a relay station, a base station, a mobile communication system, a backhaul link control method, and a program capable of contributing to efficient use of frequency resources in a mobile communication system including the relay station Is to provide.
  • the first aspect includes a relay station.
  • the relay station includes a radio communication unit and a backhaul link control unit.
  • the wireless communication unit relays data between the base station and the mobile station using a backhaul link connected to the base station and an access link connected to the mobile station.
  • the backhaul link control unit switches a use frequency of the backhaul link during operation of a relay station cell using the access link.
  • the use frequency of the backhaul link is switched from the same in-band frequency as the use frequency of the access link to the out-band frequency different from the use frequency of the access link, and from the out-band frequency. Including at least one of switching to the in-band frequency.
  • the second aspect includes a base station.
  • the base station includes a radio communication unit and a backhaul link control unit.
  • the wireless communication unit is configured to be able to perform data transfer with a mobile station connected to the relay station via an access link via a backhaul link connected to the relay station.
  • the backhaul link control unit switches the use frequency of the backhaul link during operation of the relay station cell using the access link by the relay station.
  • the use frequency of the backhaul link is switched from the same in-band frequency as the use frequency of the access link to the out-band frequency different from the use frequency of the access link, and from the out-band frequency. Including at least one of switching to the in-band frequency.
  • the third aspect includes a mobile communication system including a base station and a mobile station.
  • the relay station relays data between the base station and the mobile station using a backhaul link connected to the base station and an access link connected to the mobile station.
  • the mobile communication system according to this aspect is configured to be able to switch the use frequency of the backhaul link during operation of the relay station cell using the access link by the relay station.
  • the use frequency of the backhaul link is switched from the same in-band frequency as the use frequency of the access link to the out-band frequency different from the use frequency of the access link, and from the out-band frequency. Including at least one of switching to the in-band frequency.
  • the fourth aspect includes a backhaul link control method for connecting a base station and a mobile station.
  • the relay station is configured to perform data relay between the base station and the mobile station using the backhaul link and an access link connected to the mobile station.
  • the method according to the present aspect includes switching a use frequency of the backhaul link during operation of a relay station cell using an access link connecting the relay station and a mobile station.
  • switching the use frequency of the backhaul link includes switching from the same in-band frequency as the use frequency of the access link to an out-band frequency different from the use frequency of the access link, and the out-band frequency. To at least one of switching to the in-band frequency.
  • the fifth aspect includes a program for causing a computer to perform the method according to the fourth aspect described above.
  • a relay station capable of contributing to efficient use of frequency resources in a mobile communication system including a relay station are provided. Can be provided.
  • FIG. 2 is a block diagram showing a configuration example of a mobile communication system according to the first embodiment.
  • 3 is a block diagram showing a configuration example of a base station in the first embodiment.
  • FIG. 3 is a block diagram illustrating a configuration example of a relay station in Embodiment 1.
  • FIG. 3 is a block diagram showing a configuration example of a mobile station in Embodiment 1.
  • FIG. 4 is a sequence diagram showing an example of a backhaul link control procedure in the first embodiment.
  • 3 is a flowchart showing an operation example of a relay station in the first embodiment.
  • FIG. 10 is a sequence diagram showing an example of a backhaul link control procedure in the second embodiment.
  • 6 is a flowchart illustrating an operation example of a relay station in the second embodiment.
  • 6 is a flowchart showing an operation example of a base station in the second embodiment.
  • FIG. 11 is a sequence diagram showing an example of a backhaul link control procedure in the third embodiment.
  • 12 is a flowchart illustrating an operation example of a relay station in the third embodiment.
  • 10 is a flowchart showing an operation example of a base station in the third embodiment.
  • FIG. 10 is a block diagram illustrating a configuration example of a management device according to a fourth embodiment.
  • FIG. 10 is a sequence diagram showing an example of a backhaul link control procedure in the fourth embodiment.
  • 10 is a flowchart illustrating an operation example of the management device according to the fourth embodiment.
  • FIG. 3 is a block diagram showing a configuration example of the mobile communication system according to the present embodiment.
  • the radio communication system according to the present embodiment will be described as an FDD (Frequency division Duplex) -OFDMA, more specifically, an LTE-Advanced radio communication system based on the LTE scheme.
  • the base station (eNB) 1 belongs to the mobile carrier's core network (CN) 4, and is between the mobile station (eNB-UE) 3-1 and the core network (CN) 4.
  • the base station 1 is a base station that can accept the attribution of the relay station 2 (that is, a base station that can operate as a DeNB), and can also accept the attribution of the mobile station 3-1.
  • Relay station (RN) 2 connects base station 1 and the backhaul link (BL1 in FIG. 3). Further, the relay station (RN) 2 operates the relay station cell 20 using the access link (AL2 in FIG. 3), and connects to the mobile station (RN-UE) 3-2 through the access link (AL2). Data relay is performed between the base station 1 and the mobile station 3-2.
  • the relay station 2 can be connected to the management apparatus 5 via the core network (CN) 4.
  • the management device 5 is an OAM system and manages information set by a mobile communication carrier.
  • the relay station 2 can acquire information (i.e. donor cell list) from the management device 5, and performs initial setting of the backhaul link and the access link according to the RN startup procedure described in Non-Patent Document 3.
  • the procedure for performing the initial setting of the relay station 2 using the information (i.e. donor cell list) distributed from the management device 5 is merely a request based on the LTE standard. That is, the relay station 2 can perform initial setting without performing communication with the management device 5.
  • information relating to the initial setting of the relay station 2 may be stored in advance in a storage device in the relay station 2. Further, information regarding the initial setting of the relay station 2 may be transmitted from the base station 1 to the relay station 2.
  • relay station 2 and base station 1 connect a backhaul link (BL1), and relay station 2 operates relay station cell 20 using an access link (AL2).
  • the operating frequency of the backhaul link (BL1) (hereinafter referred to as the backhaul link frequency) can be switched.
  • switching of the backhaul link frequency is the same frequency (hereinafter referred to as in-band frequency) as the frequency used for the access link (AL2) to a frequency different from the frequency used for the access link (AL2) (hereinafter referred to as out-band frequency). And at least one of switching from an out-band frequency to an in-band frequency.
  • the operation state of the backhaul link (BL1) is in- It is possible to switch from band operation to out-band operation, or from out-band operation to in-band operation.
  • the determination of switching of the backhaul link frequency may be performed by the relay station 2 or the base station 1. Further, the switching of the backhaul link frequency may be determined by another device (higher level device) in the mobile communication system, or may be performed by an OAM system that monitors the mobile communication system. That is, the determination subject of the switching condition of the backhaul link frequency may be appropriately determined according to the switching condition to be used.
  • the relay station 2 or the base station 1 or both have information necessary for the determination (eg, the traffic information of the relay station cell 20, the base station The traffic information of the cell 10, the power consumption information of the base station 1, etc.) may be reported to the host device or the OAM system.
  • the host device or the OAM system may determine switching of the backhaul link frequency with reference to information received from the relay station 2 or the base station 1 or both.
  • the mobile communication system is provided with a backhaul link on condition that the traffic volume processed by relay station 2 decreases during out-band operation.
  • the frequency may be switched from the out-band frequency to the in-band frequency.
  • the mobile communication system may switch the backhaul link frequency from the out-band frequency to the in-band frequency when it is determined that the traffic volume processed by the relay station 2 falls below a predetermined threshold.
  • the amount of traffic processed by the relay station 2 is, for example, the amount of data packets transferred to the access link (AL2), the amount of data packets transferred through the backhaul link (BL1), or the mobile station 3 connected to the relay station cell 20 It may be calculated using the total number of -2, or a combination of at least two of these.
  • the traffic amount processed by the relay station 2 may be calculated by the relay station 2, the base station 1, other devices in the mobile communication system, or the OAM server.
  • In-band operation generally has more frequency resource restrictions than out-band operation, so the amount of traffic that can be processed by base station 1 and relay station 2 is limited. However, when the amount of traffic processed by the relay station 2 is small, the amount of traffic to be processed by the base station 1 and the relay station 2 is also small. For this reason, it is preferable to switch from out-band operation to in-band operation according to the phenomenon of traffic volume processed by the relay station 2.
  • In-band operation uses the same frequency (for example, RF1) for the backhaul link (BL1) and the access link (AL1 and AL2). For this reason, the mobile communication system can efficiently use frequency resources. Further, by switching from the out-band operation to the in-band operation, the base station 1 can stop radio transmission at an unused frequency (for example, RF2). Therefore, it is possible to contribute to reduction of power consumption of the base station 1.
  • the mobile communication system is provided with a backhaul link on condition that the traffic volume processed by relay station 2 has increased during in-band operation.
  • the frequency may be switched from the in-band frequency to the out-band frequency.
  • the mobile communication system may switch the backhaul link frequency from the in-band frequency to the out-band frequency when it is determined that the traffic volume processed by the relay station 2 exceeds a predetermined threshold.
  • the radio communication system can efficiently use frequency resources by in-band operation when traffic is low, and can cope with traffic increase by switching to out-band operation.
  • (B) Traffic volume processed by base station 1 The mobile communication system according to the present embodiment changes the backhaul link frequency from the out-band frequency to the in-band frequency on the condition that the traffic volume processed by the base station 1 has decreased. You may switch to the band frequency. Also, the mobile communication system according to the present embodiment may switch the backhaul link frequency from the in-band frequency to the out-band frequency on condition that the traffic volume processed by the base station 1 has increased.
  • the mobile communication system may switch between out-band operation and in-band operation on condition that the total amount of traffic processed by relay station 2 and base station 1 has fluctuated.
  • the backhaul link frequency may be switched from the out-band frequency to the in-band frequency on the condition that the total traffic volume has decreased.
  • the backhaul link frequency may be switched from the in-band frequency to the out-band frequency on condition that the total traffic volume has increased.
  • the mobile communication system according to the present embodiment may switch between out-band operation and in-band operation according to the time zone. That is, the mobile communication system according to the present embodiment uses an out-band frequency for the backhaul link (BL1) in a predetermined first time zone, and backhauls in a predetermined second time zone. An in-band frequency may be used for the link (BL1).
  • the second time zone may be a time zone in which the amount of traffic to be processed by the relay station 2 or the base station 1 is assumed to be smaller than that of the first time zone.
  • the second time zone may be nighttime and the first time zone may be daytime.
  • the operator of the mobile communication system may set the second time zone as a time zone in which the power consumption of the base station 1 is desired to be suppressed.
  • wireless communications system can perform in-band operation in the 2nd time slot
  • the mobile communication system includes a base station 1, a plurality of base stations including base station 1, relay station 2, or relay station 2 and base station 1
  • the backhaul link frequency may be switched from the out-band frequency to the in-band frequency on condition that power consumption of at least a part of the mobile communication system has increased.
  • the wireless communication system can suppress power consumption of the mobile communication system by switching from out-band operation to in-band operation.
  • FIG. 4 is a block diagram showing a configuration example of the base station 1.
  • the radio communication unit 11 receives an uplink signal transmitted from the mobile station 3-1 or the relay station 2 via an antenna.
  • the reception data processing unit 13 restores the received uplink signal.
  • the obtained received data is transferred to the core network 4 via the communication unit 14.
  • the transmission data processing unit 12 stores the data acquired from the communication unit 14 for the mobile stations 3-1, 3-2 or the relay station 2 in a buffer set for each mobile station and for each bearer, error correction coding,
  • a transport channel is generated by performing rate matching, interleaving, and the like. Further, the transmission data processing unit 12 adds a control information to the data sequence of the transport channel to generate a radio frame.
  • the wireless communication unit 11 performs a process such as orthogonal modulation, frequency conversion, and signal amplification of the transmission symbol sequence to generate a downlink signal, and transmits this to the mobile station 3-1 or the relay station 2.
  • the backhaul link control unit 15 controls transmission timing related to communication with the relay station 2 via the backhaul link, radio resource allocation, and a frequency used in the backhaul link.
  • FIG. 5 is a block diagram showing a configuration example of the relay station 2.
  • the relay station 2 has a function equivalent to that of the base station 1 unless otherwise specified.
  • the lower radio link communication unit 21 receives an uplink signal transmitted from the mobile station 3-2 via an antenna.
  • the reception data processing unit 23 has both functions of a reception data processing unit 13 of the base station 1 and a transmission data processing unit 34 of the mobile station 3 described later.
  • the reception data obtained by the reception data processing unit 23 is transmitted to the base station 1 via the upper radio link communication unit 24.
  • the transmission data processing unit 22 has both functions of a transmission data processing unit 12 of the base station 1 and a reception data processing unit 32 of the mobile station 3 described later.
  • the transmission data processing unit 22 generates a transmission symbol sequence from the transmission data transmitted toward the mobile station 3-2 acquired from the upper radio link communication unit 24.
  • the lower radio link communication unit 21 generates a downlink signal from the symbol string and transmits it to the mobile station 3-2.
  • the backhaul link control unit 25 performs communication control with the base station via the backhaul link such as selection of a frequency used for the backhaul link.
  • FIG. 6 is a block diagram illustrating a configuration example of the mobile station 3.
  • the wireless communication unit 31 receives a downlink signal via an antenna.
  • the received data processing unit 32 restores the received data from the received downlink signal and sends it to the buffer unit 35.
  • the received data stored in the buffer unit 35 is read out and used according to its purpose.
  • the transmission data control unit 33, the transmission data processing unit 34, and the wireless communication unit 31 generate an uplink signal using the transmission data stored in the buffer unit 35, and transmit it to the base station 1 or the relay station 2 To do.
  • FIG. 7 is a sequence diagram showing an example of a backhaul link control procedure in the first embodiment.
  • FIG. 7 shows the interaction between the base station 1, the relay station 2, and the mobile stations 3-1 and 3-2, where “eNB” is the base station 1, “RN” is the relay station 2, and “RN” -UE “corresponds to mobile station 3-2 belonging to RN, and” eNB-UE "corresponds to mobile station 3-1 belonging to eNB including DeNB.
  • Steps S101 to S103 show data communication between eNB 1, RN 2, UE 3-1 and 3-2 in out-band operation.
  • the eNB 1 and the RN 2 perform data communication using the frequency RF2 as the backhaul link frequency (step S101).
  • the RN 2 and RN-UE 3-2 perform data communication using the frequency RF1 as the frequency of the access link (AL2) (step S102).
  • the eNB 1 and eNB-UE 3-1 perform data communication using the frequency RF1 as the frequency of the access link (AL1) (step S103).
  • step S104 RN 2 decides switching of the backhaul link frequency, here switching from the out-band frequency RF2 to the in-band frequency RF1.
  • the determination may be performed using any of the above-described switching conditions of the backhaul link frequency.
  • the RN 2 monitors the traffic of the RN cell 20. Then, the RN 2 may determine switching to the in-band frequency when the traffic volume of the RN cell 20 falls below a preset threshold value.
  • step S105 RN 2 transmits a request for changing the frequency used in the backhaul link to eNB 1.
  • the eNB 1 instructs the RN 2 to change the backhaul link setting (frequency, presence / absence of resource division, etc.) in response to receiving the backhaul link frequency change request.
  • the eNB-1 may stop radio transmission at the frequency RF2.
  • Step S107 RN 2 changes the setting of the backhaul link including frequency switching based on the backhaul link change instruction from eNB 1 (step S107).
  • Steps S108 to S110 show data communication between eNB 1, RN 2, UE 3-1 and 3-2 after switching the backhaul link frequency, that is, after switching from out-band operation to in-band operation. ing.
  • the eNB 1 and the RN ⁇ ⁇ ⁇ 2 perform data communication using the frequency RF1 as the backhaul link frequency (step S108).
  • the RN 2 and the RN-UE 3-2 perform data communication using the frequency RF1 as the frequency of the access link (AL2) (step S109).
  • the eNB 1 and eNB-UE 3-1 perform data communication using the frequency RF1 as the frequency of the access link (AL1) (step S110).
  • FIG. 8 is a flowchart showing an operation example of the relay station 2 regarding switching of the backhaul link frequency.
  • the relay station 2 determines switching of the backhaul link frequency.
  • the relay station 2 returns to Step S201 for determining switching of the backhaul link frequency.
  • the relay station 2 transmits a backhaul link change request to the base station 1 (Step S202).
  • step S203 the relay station 2 determines whether a backhaul link change request has been received from the base station 1.
  • the relay station 2 changes the setting of the backhaul link including switching of the backhaul link frequency (Step S204).
  • the relay station 2 returns to Step S203 for determining whether or not the backhaul link change request has been received.
  • FIG. 9 is a flowchart showing an operation example of the base station 1 regarding switching of the backhaul link frequency.
  • the base station 1 determines whether or not a backhaul link change request has been received.
  • the base station 1 transmits the backhaul link change request to the relay station 2 (Step S302).
  • the base station 1 returns to Step S301 for determining reception of the backhaul link change request.
  • the base station 1 stops radio transmission at this frequency when an unused frequency is generated due to switching of the backhaul link frequency, particularly switching from the out-band frequency to the in-band frequency. To do.
  • the frequency used for the backhaul link (BL1) ( Hereinafter, the backhaul link frequency) can be switched. For this reason, the mobile communication system can efficiently use frequency resources. Further, by switching from the out-band operation to the in-band operation, the base station 1 can stop radio transmission at an unused frequency (for example, RF2). Therefore, it is possible to contribute to reduction of power consumption of the base station 1.
  • the mobile communication system After switching the backhaul link frequency, the mobile communication system according to the present embodiment returns the backhaul link frequency before switching in accordance with the deterioration of radio parameters of relay station cell 20.
  • the radio parameter of the relay station cell 20 can be rephrased as the communication quality of the relay station cell 20.
  • a specific example of the radio parameter of the relay station cell 20 is the downlink throughput (data amount that can be transmitted per unit time) of the RN cell 20, or the number of mobile stations that can be connected to the RN cell 20.
  • the mobile communication system may switch back the backhaul link frequency when the difference (decrease width) in throughput before and after switching the backhaul link frequency exceeds a predetermined threshold. Further, the mobile communication system may switch back the backhaul link frequency when the throughput after switching the backhaul link frequency falls below a predetermined threshold.
  • the decision of switching backhaul link frequency may be made by the relay station 2 or the base station 1.
  • the determination of backhaul link frequency switching may be performed by another device (higher-order device) in the mobile communication system, or by an OAM system that monitors the mobile communication system.
  • the determination subject of the backhaul link frequency switch-back may be appropriately determined according to the frequency switch-back condition.
  • the switching of the backhaul link frequency causes the communication quality (eg, throughput) of the relay station cell 20 to deteriorate, the switching operation for returning the backhaul link frequency to the original state I do. Therefore, it is possible to contribute to efficient use of frequency resources and reduction of power consumption of the base station 1 while suppressing deterioration of communication quality of the RN cell 20.
  • the communication quality eg, throughput
  • FIG. 10 is a sequence diagram showing an example of a backhaul link control procedure in the second embodiment. Processes and operations from step S101 to step S110 in FIG. 10 are the same as the step group having the same reference numerals in FIG. 7 described in the first embodiment. Therefore, only the difference from FIG. 7 will be described here.
  • step S401 after changing the setting of the backhaul link, the RN 2 measures whether or not the radio parameter (in other words, communication quality) of the RN cell 20 has deteriorated.
  • the RN 2 transmits a backhaul link recovery request to the eNB 1 in order to return the backhaul link setting including the backhaul link frequency before switching (step S402).
  • the eNB ⁇ 1 instructs the RN 2 to change the backhaul link setting (frequency, presence / absence of resource division, etc.) in response to receiving the recovery request.
  • the eNB 1 restarts the radio transmission at the frequency before the switching.
  • step S404 RN2 restores the backhaul link setting in response to receiving the backhaul link change instruction.
  • the data communication before the change is restored (from step S101 to step S103).
  • Steps S405 to S407 perform data communication between eNB 1, RN 2, UE 3-1 and 3-2 after switching backhaul link frequency, that is, after switching from in-band operation to out-band operation. Show. Accordingly, steps S405 to S407 are the same as steps S101 to S103.
  • FIG. 11 is a flowchart showing an operation example of the relay station 2 regarding switching and switching backhaul link frequencies. Processes and operations from step S201 to step S204 in FIG. 11 are the same as those in the step group having the same reference numerals in FIG. 8 described in the first embodiment. Therefore, only the difference from FIG. 8 will be described here.
  • step S501 after switching the backhaul link frequency, the relay station 2 determines whether or not the radio parameters of the relay station cell 20 have deteriorated. If the radio parameter has not deteriorated (No in step S501), the relay station 2 ends the procedure of FIG. On the other hand, when the radio parameter is degraded (Yes in step S501), the relay station 2 transmits a backhaul link recovery request to the DeNB for switching back the backhaul link frequency (step S502). In step S503, the relay station 2 determines whether a backhaul link change request has been received from the base station 1. When the backhaul link change request is received (Yes in Step S503), the relay station 2 changes the setting of the backhaul link including switching back of the backhaul link frequency (Step S504). When the backhaul link change request has not been received (No in Step S503), the relay station 2 returns to Step S503 for determining whether or not the backhaul link change request has been received.
  • FIG. 12 is a flowchart showing an operation example of the base station 1 regarding backhaul link frequency switching back.
  • the base station 1 determines whether or not a backhaul link recovery request has been received from the relay station 2.
  • the base station 1 instructs the RN to change the setting of the backhaul link including the backhaul link frequency switch back (step S602). If the backhaul link recovery request has not been received (No in step S601), the base station 1 returns to step S601 to determine whether or not a backhaul link recovery request has been received.
  • the radio parameter of the relay station cell 20 is changed according to the deterioration of the deterioration being smaller than the reference. Stop operation.
  • the mobile communication system may stop the operation of the relay station cell 20 when the throughput difference (decrease width) before and after the switching of the backhaul link frequency falls below a predetermined threshold.
  • the mobile communication system may stop the operation of the relay station cell 20 when the throughput after switching the backhaul link frequency exceeds a predetermined threshold.
  • the decision to stop operation of the relay station cell 20 may be made by the relay station 2 or the base station 1.
  • the operation stop determination of the relay station cell 20 may be performed by another device (higher-order device) in the mobile communication system, or may be performed by an OAM system that monitors the mobile communication system. That is, the determination subject of the operation stop of the relay station cell 20 may be appropriately determined according to the operation stop condition of the relay station cell 20.
  • the mobile communication system stops the operation of the relay station cell 20 when the deterioration of the communication quality of the relay station cell 20 after switching of the backhaul link frequency is small. Therefore, in addition to the efficient use of frequency resources and the reduction of power consumption of the base station 1, it can also contribute to the reduction of power consumption of the relay station 2.
  • FIG. 13 is a sequence diagram showing an example of a backhaul link control procedure in the third embodiment. Processes and operations from step S101 to step S110 in FIG. 13 are the same as those in the step group having the same reference numerals in FIG. 7 described in the first embodiment. Therefore, only the difference from FIG. 7 will be described here.
  • Step S701 after changing the setting of the backhaul link, the RN 2 measures whether or not the radio parameter (in other words, communication quality) of the RN cell 20 has deteriorated. If the degradation of the line parameter is below the reference, the RN 2 transmits an RN cell suspension notification to the eNB 1 in order to suspend the RN cell 20 (step S702). In step S703, the eNB 1 stops data transmission addressed to the RN 2 in response to receiving the RN cell suspension notification (step S703). The RN 2 suspends the operation of the RN cell 20 after transmitting the RN cell suspension notification (step S704). Steps S705 and S706 indicate data communication after the RN cell 20 is suspended. That is, the RN-UE 3-2 connected to the RN cell 20 before suspending the RN cell directly belongs to the eNB cell 10 through the access link (AL1) and performs data communication.
  • the radio parameter in other words, communication quality
  • FIG. 14 is a flowchart showing an operation example of the relay station 2 regarding switching of the backhaul link frequency and suspension of operation of the relay station cell 20. Processes and operations from step S201 to step S204 in FIG. 14 are the same as those in the step group having the same reference numerals in FIG. 8 described in the first embodiment. Therefore, only the difference from FIG. 8 will be described here.
  • step S801 after switching the backhaul link frequency, the relay station 2 determines whether or not the radio parameters of the relay station cell 20 have deteriorated. If the degradation of the radio parameters exceeds the standard (No in step S801), the relay station 2 ends the procedure of FIG. On the other hand, when the degradation of the radio parameter is below the reference (Yes in step S801), the relay station 2 transmits a relay station cell suspension notification to the base station 1 (step S802). In step S803, the relay station 2 stops the operation of the relay station cell 20.
  • FIG. 15 is a flowchart showing an operation example of the base station 1 regarding the suspension of operation of the relay station cell 20.
  • the base station 1 determines whether or not a relay station cell suspension notification is received from the relay station 2.
  • the base station 1 stops data transmission to the relay station 2 (step S902).
  • the base station 1 returns to step S901 for determining reception of the relay station cell suspension notification.
  • Embodiment 4 a specific example of a backhaul link frequency switching procedure taking into account the power consumption of the mobile communication system described in Embodiment 1 will be described.
  • the mobile communication system monitors the total power consumption of the plurality of base stations 1 or the plurality of relay stations 2 or both in the management apparatus 5, and responds to the increase in the total power consumption. Switch backhaul link frequency from out-band frequency to in-band frequency. Node groups (base stations and relay stations) to be monitored may be determined according to their geographical arrangement.
  • the mobile communication system can switch the backhaul link frequency in consideration of the total power consumption of a plurality of nodes included in the mobile communication system. Therefore, the suppression of the power consumption of the base station 1 can contribute to the suppression of the total power consumption of a plurality of nodes.
  • the configuration examples of the base station 1, the relay station 2, and the mobile station 3 may be the same as those shown in FIGS.
  • FIG. 16 is a block diagram showing a configuration example of the management apparatus 5 in the present embodiment.
  • the communication unit 51 transmits and receives data packets between the base station 1 and the relay station 2 via the core network 4.
  • the reception data processing unit 53 restores information included in the received uplink data packet. When the restored information is information regarding power consumption, the reception data processing unit 53 sends this to the backhaul link management unit 54.
  • the backhaul link management unit 54 manages the frequency used for the backhaul link, the power consumption of the plurality of base stations 1, and the like. Further, the backhaul link management unit 54 instructs the change of the backhaul link frequency according to the total power consumption of the plurality of base stations 1 to be managed.
  • the transmission data processing unit 52 receives control information related to the backhaul link frequency from the backhaul link management unit 54, the transmission data processing unit 52 transmits the control information to the corresponding base station 1 and relay station 2.
  • FIG. 17 is a sequence diagram showing an example of a backhaul link control procedure in the fourth embodiment.
  • the sequence in FIG. 17 is different from the sequence in FIG. 7 in that the determination subject of the backhaul frequency is not the RN 2 but the management device 5. Accordingly, the processes and operations in steps S101 to S103 and steps S106 to S110 in FIG. 17 are the same as those in the step group having the same reference numerals shown in FIG. Therefore, only the difference from FIG. 7 will be described here.
  • eNB 1 notifies the management device 5 (i.e. OAM server) of information (e.g. power consumption or power usage rate) regarding the power consumption of eNB 1. This notification may be performed periodically at a predetermined cycle, or may be performed when power consumption exceeds a reference.
  • the management device 5 aggregates the power consumption information received from the plurality of eNBs 1 and controls the power consumption. Specifically, when the total power consumption of the plurality of eNB 1 exceeds a predetermined reference level, the management device 5 identifies the eNB 1 having an out-band operation backhaul link, and the eNB 1 A backhaul link change request is transmitted to (step S1103).
  • This backhaul link change request includes an instruction to switch the backhaul frequency to the in-band frequency. Note that when the eNBe1 is specified, the management device 5 changes the backhaul link to in-band operation to generate a frequency that does not require data transmission, and can stop transmission at this frequency. You may choose eNB 1.
  • FIG. 18 is a flowchart showing an operation example of the management apparatus 5 related to switching of the backhaul link frequency in the fourth embodiment.
  • the management device 5 receives power consumption information from the plurality of base stations 1.
  • the management device 5 determines whether or not the total power consumption of the plurality of base stations 1 exceeds the reference level. When the total power consumption exceeds the reference level (Yes in step S1202), the management apparatus 5 identifies the base station 1 and the relay station 2 that should change the backhaul link for out-band operation, and changes the backhaul link. Send a request. This frequency is changed from the out-band frequency to the in-band frequency.
  • the management apparatus 5 collects power consumption information of a plurality of base stations 1 and selects the base station 1 whose configuration of the backhaul link should be changed. For this reason, it is possible to suppress power consumption in consideration of the plurality of base stations 1 or the entire mobile communication system.
  • the backhaul link may be controlled based on a ratio (usage rate) to the maximum power consumption.
  • the management device 5 monitors power consumption information of electronic devices such as server computers as well as a plurality of base stations 1, and changes the backhaul link configuration when the total power consumption exceeds a reference level Good. Further, when the ratio (usage rate) to the maximum power consumption is used as the power consumption information, the base station 1 may notify the management device 5 of its own power usage rate. The management device 5 may change the configuration of the backhaul link when the number of base stations whose power usage rate is higher than the threshold is equal to or greater than a predetermined number.
  • Embodiments 1 to 4 described above mobile communication systems that support LTE relay stations have been described.
  • the application destination of these embodiments is not limited to a mobile communication system that supports LTE relay stations. That is, these embodiments are widely applicable to mobile communication systems including relay stations.
  • ASIC Application Specific Specific Integrated Circuit
  • Non-transitory computer readable media include various types of tangible storage media (tangible storage medium). Examples of non-transitory computer-readable media include magnetic recording media (eg flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (eg magneto-optical discs), CD-ROMs (Read Only Memory), CD-Rs, CD-R / W, semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable ROM), flash ROM, RAM (random access memory)) are included.
  • the program may also be supplied to the computer by various types of temporary computer-readable media. Examples of transitory computer readable media include electrical signals, optical signals, and electromagnetic waves.
  • the temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.
  • Embodiments 1 to 4 can be appropriately combined. Furthermore, the above-described embodiment is merely an example relating to application of the technical idea obtained by the present inventors. That is, the technical idea is not limited to the above-described embodiment, and various changes can be made.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

L'invention concerne une station de relais (2) qui met en oeuvre un relais de données entre une station de base (1) et une station mobile (3-2) au moyen d'une liaison de raccordement (BL1), laquelle est connectée à la station de base (1), et d'une liaison d'accès (AL2) qui est connectée à la station mobile (3-2). Un système de télécommunication mobile est configuré de sorte que pendant la commande d'une cellule (20) de la station de relais au moyen de la liaison d'accès (AL2), par l'intermédiaire de la station de relais (2), il est possible de changer la fréquence utilisée par la liaison de raccordement (BL1). Le changement de la fréquence utilisée par la liaison de raccordement (BL1) comprend au moins un des changements suivants: changement d'une fréquence intrabande identique à celle utilisée par la liaison d'accès (AL2) à une fréquence hors bande, différente de la fréquence utilisée par la liaison d'accès (AL2); et changement de la fréquence hors bande à la fréquence intrabande.
PCT/JP2012/003037 2011-08-11 2012-05-09 Station de relais, station de base, système de télécommunication mobile, procédé de commande de liaison de raccordement et support lisible par un ordinateur WO2013021526A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2013527843A JP6065835B2 (ja) 2011-08-11 2012-05-09 中継局、基地局、移動通信システム、バックホールリンクの制御方法、及びプログラム

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2011175925 2011-08-11
JP2011-175925 2011-08-11

Publications (1)

Publication Number Publication Date
WO2013021526A1 true WO2013021526A1 (fr) 2013-02-14

Family

ID=47668069

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2012/003037 WO2013021526A1 (fr) 2011-08-11 2012-05-09 Station de relais, station de base, système de télécommunication mobile, procédé de commande de liaison de raccordement et support lisible par un ordinateur

Country Status (2)

Country Link
JP (1) JP6065835B2 (fr)
WO (1) WO2013021526A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2015098228A1 (ja) * 2013-12-24 2017-03-23 ソニー株式会社 無線通信装置、通信制御装置、無線通信方法及び通信制御方法

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6025892B2 (ja) * 2015-03-13 2016-11-16 ソフトバンク株式会社 移動通信システム

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008520169A (ja) * 2004-11-10 2008-06-12 インターデイジタル テクノロジー コーポレーション 無線通信ネットワークの無線リソースを管理するための方法および装置

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008520169A (ja) * 2004-11-10 2008-06-12 インターデイジタル テクノロジー コーポレーション 無線通信ネットワークの無線リソースを管理するための方法および装置

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
ITRI: "Asymmetric carrier configuration for Relay operation", 3GPP TSG-RAN WG1 #61 R1-103278, 14 May 2010 (2010-05-14) *
NEC CORPORATION: "Need of dedicated SI provisioning for Type 1a/1b", 3GPP TSG RAN2 MEETING #71 R2-104545, 27 August 2010 (2010-08-27) *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPWO2015098228A1 (ja) * 2013-12-24 2017-03-23 ソニー株式会社 無線通信装置、通信制御装置、無線通信方法及び通信制御方法

Also Published As

Publication number Publication date
JPWO2013021526A1 (ja) 2015-03-05
JP6065835B2 (ja) 2017-01-25

Similar Documents

Publication Publication Date Title
JP5987838B2 (ja) 移動通信システム、中継局、基地局、及びこれらの制御方法
TWI578818B (zh) 用於多重跳躍為底之網路的網路發起探索和路徑選擇程序
CN107431946B (zh) 具有基站和中继节点的网络中的拥塞避免
US9451510B2 (en) Relay node configuration in preparation for handover
EP3005799B1 (fr) Systèmes et procédés de délestage de données dans des réseaux sans fil
KR101760381B1 (ko) 무선 통신 시스템, 기지국, 이동국, 통신 제어 방법, 및 컴퓨터 판독가능한 매체
US8767614B2 (en) Reporting buffering information
US12010548B2 (en) Apparatus and method for congestion handling in radio access network
CN104380803A (zh) 用于实现多个无线回程的方法和中继节点
CN104349387B (zh) 在支持双/多连接的系统中用于下行链路传输的方法和设备
KR20130005290A (ko) 업링크 송신을 위한 방법, 기지국 및 중계 노드
US20130143580A1 (en) Power Consumption Reduction within a Telecommunication Network Operating with Different Radio Access Technologies
US10349459B2 (en) Relay node RN, donor eNodeB DeNB and communication method
CN105432115A (zh) 用于双连接的方法和装置
KR20130012953A (ko) 무선 통신 시스템, 고전력 기지국, 저전력 기지국, 및 통신 제어 방법
CN107534900A (zh) 通信方法及设备
JP6065835B2 (ja) 中継局、基地局、移動通信システム、バックホールリンクの制御方法、及びプログラム
EP2335444B1 (fr) Support pour multiplexage d'équipement utilisateur dans des réseaux améliorés à relais
US10149194B2 (en) Method, apparatus, and system for establishing bearer
Krilddis et al. Feedback based relaying in long term evolution systems

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12821670

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2013527843

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12821670

Country of ref document: EP

Kind code of ref document: A1