JP6043491B2 - Radio base station and scheduling method - Google Patents

Description

  The present invention relates to a radio base station and a scheduling method.

  In a LTE (Long Term Evolution) -Advanced mobile communication system whose specification is being advanced by 3GPP, it is considered to perform CA (Carrier Aggregation).

  In the LTE-Advanced mobile communication system, the mobile station UE can perform CA using a plurality of CCs (Component Carriers) in different frequency bands simultaneously with one radio base station eNB. It is configured to be able to.

  Also, when CA is performed, the mobile station UE sets one of a plurality of CCs as a PCC (Primary Component Carrer) and the other as an SCC (Secondary Component Carrer) according to an instruction from the radio base station. ) Is configured to set as.

JP 2011-142596 A

3GPP TS 36.814 3GPP TS 36.912

  In an LTE-Advanced mobile communication system, it is considered to arrange one or a plurality of picocells in a high traffic area within a coverage area of a macrocell.

  However, in the current LTE-Advanced mobile communication system, the PDCP (Packet Data Convergence Protocol) layer and the RLC (Radio Link Control) layer are unaware of each CC, and the MAC (Media Access Control) layer is different from each CC. It is structured to be conscious about.

  On the other hand, in the current LTE-Advanced mobile communication system, the MAC layer is unaware of bearers and logical channels.

  Therefore, for example, the MAC layer of the radio base station eNB is used in a scheduling process for a mobile station UE performing CA using a macro cell and a pico cell in a high traffic area where one or more pico cells are arranged. There is a problem that the channel cannot be recognized and appropriate traffic distribution cannot be realized.

  Therefore, the present invention has been made in view of the above-described problems, and provides a radio base station and a scheduling method capable of realizing appropriate traffic distribution in scheduling processing for a mobile station UE performing CA. For the purpose.

  A first feature of the present invention is a radio base station comprising a scheduling unit configured to perform a scheduling process for a mobile station connected to a cell under the radio base station, and the scheduling unit Is summarized in that a specific type of bearer is assigned to a specific component carrier in a scheduling process for a mobile station performing CA.

  A second feature of the present invention is a radio base station comprising a scheduling unit configured to perform a scheduling process for a mobile station connected to a cell under the radio base station, and the scheduling unit The gist of the invention is that, in the scheduling process for the mobile station performing CA, the component carrier to which each bearer is allocated is determined based on the priority of the logical channel mapped to each bearer. .

  In the second aspect of the present invention, two scheduling units may be provided, and one of the scheduling units may be configured to perform a scheduling process only for a specific type of bearer.

  A third feature of the present invention is a scheduling method in a radio base station, wherein a specific type of bearer is assigned to a specific component carrier in a scheduling process for a mobile station performing CA in a cell under the radio base station. The gist is to have a process.

  A third feature of the present invention is a scheduling method in a radio base station, wherein priority of logical channels mapped to each bearer in scheduling processing for a mobile station performing CA in a cell under the radio base station. The gist is to have a step of determining a component carrier to which each bearer is assigned based on the degree.

  As described above, according to the present invention, it is possible to provide a radio base station and a scheduling method capable of realizing appropriate traffic distribution in the scheduling process for the mobile station UE performing CA.

1 is an overall configuration diagram of a mobile communication system according to a first embodiment of the present invention. FIG. 3 is a functional diagram of a radio base station according to the first embodiment of the present invention. It is a figure which shows an example of the mapping of "Logical Channel Priority" and bearer type in the radio base station which concerns on the 2nd Embodiment of this invention. 6 is a flowchart for explaining an operation of the radio base station according to the second embodiment of the present invention. It is a figure which shows an example of the mapping of "Logical Channel Priority" and bearer type in the wireless base station which concerns on the 3rd Embodiment of this invention. 10 is a flowchart for explaining an operation of the radio base station according to the third embodiment of the present invention.

(Mobile communication system according to the first embodiment of the present invention)
With reference to FIG.1 and FIG.2, the mobile communication system which concerns on the 1st Embodiment of this invention is demonstrated. The mobile communication system according to the present embodiment is an LTE-Advanced mobile communication system.

  In the mobile communication system according to the present embodiment, the mobile station UE can transmit and receive signals to and from the radio base station eNB by simultaneously using the CC of the frequency band F1 and the CC of the frequency band F2. That is, it is comprised so that CA can be performed.

  As shown in FIG. 1, in the mobile communication system according to the present embodiment, a cell # 1 is provided as a macro cell and a cell # 11 / # 12 is provided as a pico cell under the radio base station eNB. .

  Here, CC of the frequency band F1 is used in the cell # 1 (macro cell), and CC of the frequency band F2 is used in the cells # 11 / # 12 (pico cells).

  As shown in FIG. 1, for example, it is assumed that a core (coverage) band that emphasizes the area coverage range is used as the frequency band F1, and a capacity band that emphasizes high-speed communication is used as the frequency band F2. Yes.

  For example, an 800 MHz band, a 2 GHz band, or the like may be used as the frequency band F1, and a 3.5 GHz band or the like may be used as the frequency band F2.

  For example, the bandwidth of each CC may be either 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, or 20 MHz. In addition, 1.4MHz, 3MHz, 5MHz, 10MHz, or 20MHz is comprised by 6RB (Resource Block), 15RB, 25RB, 50RB, 75RB, or 100RB, respectively. Here, 1 RB is 180 kHz.

  Further, the mobile communication system according to the present embodiment is configured such that the coverage area of cell # 1 and the coverage area of cells # 11 / # 12 are geographically superimposed.

  As illustrated in FIG. 2, the radio base station eNB includes a PDCP layer function, an RLC layer function, and a MAC layer function.

  The PDCP layer function includes a ROHC (Robust Header Compression) function, a Security function, and the like.

  The RLC layer function includes a segmentation function, an ARQ function, and the like.

  The MAC layer function has one Unicast Scheduling / Priority Handling function. The Unicast Scheduling / Priority Handling function constitutes the scheduling unit 10.

  In addition, the MAC layer function includes one Multiplexing function for each mobile station UE, and includes a HARQ entity corresponding to each CC used in CA by each mobile station UE.

  Here, each CC is configured to be processed by one HARQ entity.

  The scheduling unit 10 is configured to allocate a specific type of bearer to a specific CC in the scheduling process for the mobile station UE performing CA.

  For example, the scheduling unit 10 may be configured to allocate a C-plane bearer to the PCC and allocate a U-plane bearer to the SCC in the scheduling process for the mobile station UE performing CA.

  Alternatively, the scheduling unit 10 assigns the C-plane bearer and the voice communication U-plane bearer to the PCC and assigns the packet communication U-plane bearer to the SCC in the scheduling process for the mobile station UE performing CA. It may be configured.

  Note that the scheduling unit 10 may be configured to perform scheduling processing for the mobile station UE performing the above-described CA when detecting that the CA including the pico cell is activated.

  That is, the scheduling unit 10 is configured to perform a normal scheduling process (that is, a scheduling process performed without being aware of the bearer type) when it is not detected that the CA including the pico cell is activated. It may be.

  Alternatively, the scheduling unit 10 may be configured to determine whether or not to perform the scheduling process for the mobile station performing the above-described CA according to the congestion status of each CC.

  For example, the scheduling unit 10 may be configured to perform a scheduling process on the mobile station UE performing the above-described CA when the occurrence of congestion is detected in a predetermined number of CCs.

  That is, the scheduling unit 10 may be configured to perform a normal scheduling process (that is, a scheduling process performed without being aware of the bearer type) when occurrence of congestion is detected in a predetermined number of CCs. .

  According to the mobile communication system according to the first embodiment of the present invention, the scheduling unit 10 in the MAC layer can allocate a specific type of bearer to a specific CC in the scheduling process for the mobile station UE performing CA. Therefore, appropriate traffic distribution can be realized based on the cell configuration and traffic situation in the mobile communication system.

(Mobile communication system according to the second embodiment of the present invention)
With reference to FIG.3 and FIG.4, the mobile communication system which concerns on the 2nd Embodiment of this invention is demonstrated. Hereinafter, the mobile communication system according to the second embodiment of the present invention will be described by focusing on the differences from the mobile communication system according to the first embodiment described above.

  In the mobile communication system according to the present embodiment, the scheduling unit 10 determines the CC to which each bearer is assigned based on the “Logical Channel Priority” mapped to each bearer in the scheduling process for the mobile station UE performing CA. Is configured to determine.

  For example, the scheduling unit 10 may manage a table associating bearer types, CQIs (Channel Quality Indicators), “Logical Channel Priority”, and CC identification information shown in FIG.

  The scheduling unit 10 can extract CQI, “Logical Channel Priority”, and CC associated with a specific type of bearer by referring to the table.

  Hereinafter, with reference to FIG. 4, the operation of the scheduling process for the mobile station UE performing CA in the radio base station according to the present embodiment will be described.

  As illustrated in FIG. 4, in step S101, the scheduling unit 10 determines, for each mobile station UE, the highest “Logical Channel Priority” at present from among “Logical Channel Priority” associated with the bearer for the mobile station UE. “Channel Priority” is selected, and the CC associated with the selected “Logical Channel Priority” is extracted.

  Here, the scheduling unit 10 determines to assign the bearer for the mobile station UE associated with the selected “Logical Channel Priority” to the CC associated with the selected “Logical Channel Priority”.

  In step S102, the scheduling unit 10 calculates a scheduling coefficient for each mobile station UE. Here, the scheduling unit 10 may calculate a scheduling coefficient for each mobile station UE and for each CC.

  Further, the scheduling unit 10 may calculate the scheduling coefficient using the CQI associated with the selected “Logical Channel Priority”.

  In step S103, the scheduling unit 10 determines a mobile station UE to be subjected to scheduling processing based on the calculated scheduling coefficient.

  For example, the scheduling unit 10 may determine that the mobile station UE having the largest scheduling coefficient is the mobile station UE to be subjected to the scheduling process.

  Note that the scheduling unit 10 may determine a mobile station UE to be subjected to scheduling processing for each CC.

  According to the mobile communication system according to the second embodiment of the present invention, the scheduling unit 10 in the MAC layer performs “Logical Channel Priority” associated with the bearer in the scheduling process for the mobile station UE performing CA. Therefore, appropriate traffic distribution and priority control can be realized based on the cell configuration and traffic situation in the mobile communication system.

(Mobile communication system according to the third embodiment of the present invention)
With reference to FIG.5 and FIG.6, the mobile communication system which concerns on the 3rd Embodiment of this invention is demonstrated. Hereinafter, the mobile communication system according to the third embodiment of the present invention will be described by focusing on the differences from the mobile communication systems according to the first and second embodiments described above.

  In the mobile communication system according to the present embodiment, the radio base station eNB includes two scheduling units 10A / 10B.

  Here, the scheduling unit 10A may be configured to perform a scheduling process only for a specific type of bearer (for example, an SRB or a voice communication bearer).

  Then, the scheduling unit 10B may be configured to perform scheduling processing for the remaining types of bearers (for example, U-plane bearers for packet communication).

  The two scheduling units 10A / 10B are configured to perform the scheduling process independently.

  Each of the two scheduling units 10A / 10B may manage a table associating the bearer type, CQI, and “Logical Channel Priority” shown in FIG.

  The scheduling unit 10A / 10B can extract CQI and “Logical Channel Priority” associated with a specific type of bearer by referring to the table.

  Hereinafter, with reference to FIG. 6, the operation of the scheduling process for the mobile station UE performing CA in the radio base station according to the present embodiment will be described.

  As shown in FIG. 6, in step S201A, the scheduling unit 10A, for each mobile station UE, from among the “Logical Channel Priority” associated with the SRB for the mobile station UE and the voice communication bearer, , Select the highest “Logical Channel Priority”.

  Here, the scheduling unit 10A determines to allocate the SRB and voice communication bearer for the mobile station UE associated with the selected “Logical Channel Priority” to the CC (for example, PCC) for the scheduling unit 10A. .

  In step S202A, the scheduling unit 10A calculates a scheduling coefficient for each mobile station UE.

  In step S203A, the scheduling unit 10A determines a mobile station UE that is a target of scheduling processing based on the calculated scheduling coefficient.

  On the other hand, in step S201B, the scheduling unit 10B determines, for each mobile station UE, a bearer other than the SRB for the mobile station UE and a bearer for voice communication (for example, “Logical Channel associated with a U-plane bearer for packet communication). The highest “Logical Channel Priority” at the present time is selected from “Priority”.

  Here, the scheduling unit 10B determines to allocate the SRB and voice communication bearer for the mobile station UE associated with the selected “Logical Channel Priority” to the CC (for example, PCC) for the scheduling unit 10A. .

  In step S202B, the scheduling unit 10B calculates a scheduling coefficient for each mobile station UE.

  In step S203B, the scheduling unit 10B determines a mobile station UE that is a target of the scheduling process based on the calculated scheduling coefficient.

  The characteristics of the present embodiment described above may be expressed as follows.

  The first feature of the present embodiment is a radio base station eNB, which is configured to perform scheduling processing for mobile stations UE connected to cells # 1 / # 11 / # 12 under the radio base station eNB. The scheduling unit 10 is configured to allocate a specific type of bearer to a specific CC (component carrier) in the scheduling process for the mobile station UE performing CA. And

  In the first feature of the present embodiment, the scheduling unit 10 assigns a C-plane bearer to a PCC (primary carrier) and assigns a U-plane bearer to an SCC (subcarrier) in the scheduling process for the mobile station UE performing CA. ).

  In the first feature of the present embodiment, the scheduling unit 10 allocates the C-plane bearer and the voice communication U-plane bearer to the PCC in the scheduling process for the mobile station UE performing CA, and uses the packet communication U- You may be comprised so that a plane bearer may be allocated to SCC.

  In the first feature of the present embodiment, the scheduling unit 10 is configured to perform scheduling processing for the mobile station UE performing the above-described CA when detecting that the CA including the pico cell is activated. It may be.

  In the first feature of the present embodiment, the scheduling unit 10 is configured to determine whether to perform scheduling processing for the mobile station performing the above-described CA according to the congestion status of each CC. Also good.

  The second feature of the present embodiment is a radio base station eNB, which is configured to perform a scheduling process for mobile stations UE connected to cells # 1 / # 11 / # 12 under the radio base station eNB. The scheduling unit 10 is based on “Logical Channel Priority (logical channel priority)” mapped to each bearer in the scheduling process for the mobile station UE performing CA. The gist is that it is configured to determine the CC to which each bearer is assigned.

  In the second feature of the present embodiment, two scheduling units 10 are provided, and one of the two scheduling units 10 may be configured to perform a scheduling process only for a specific type of bearer. Good.

  In the second feature of the present embodiment, the scheduling unit 10 is configured to perform scheduling processing for the mobile station UE performing CA when detecting that the CA including the pico cell is activated. Also good.

  A third feature of the present embodiment is a scheduling method in the radio base station eNB, and in a scheduling process for a mobile station UE performing CA in a cell under the radio base station eNB, a specific type of bearer is identified as a specific CC. The gist is to have a step of assigning to

  A third feature of the present embodiment is a scheduling method in the radio base station eNB, which is mapped to each bearer in the scheduling process for the mobile station UE performing CA in the cell under the radio base station eNB. The gist is to have a step of determining a CC to which each bearer is allocated based on “Logical Channel Priority”.

  Note that the operation of the radio base station eNB described above may be implemented by hardware, may be implemented by a software module executed by a processor, or may be implemented by a combination of both.

  The software module includes a RAM (Random Access Memory), a flash memory, a ROM (Read Only Memory), an EPROM (Erasable Programmable ROM), an EEPROM (Electronically Erasable and Programmable ROM, a hard disk, a registerable ROM, a hard disk). Alternatively, it may be provided in a storage medium of an arbitrary format such as a CD-ROM.

  Such a storage medium is connected to the processor so that the processor can read and write information from and to the storage medium. Further, such a storage medium may be integrated in the processor. Such a storage medium and processor may be provided in the ASIC. Such an ASIC may be provided in the radio base station eNB. Further, the storage medium and the processor may be provided in the radio base station eNB as a discrete component.

  Although the present invention has been described in detail using the above-described embodiments, it is obvious to those skilled in the art that the present invention is not limited to the embodiments described in this specification. The present invention can be implemented as modified and changed modes without departing from the spirit and scope of the present invention defined by the description of the scope of claims. Therefore, the description of the present specification is for illustrative purposes and does not have any limiting meaning to the present invention.

eNB ... radio base stations # 1, # 11, # 12 ... cell 10 ... scheduling unit

Claims (6)

A wireless base station,
A scheduling unit configured to perform a scheduling process for a mobile station connected to a cell under the radio base station;
In a scheduling process for a mobile station performing CA (Carrier Aggregation), the scheduling unit detects a specific bearer of a specific type assigned to a specific component carrier when detecting that a CA including a pico cell is activated. performs scheduling process, when the CA including the picocell does not detect that it is activated, no line base characterized in that it is configured to perform scheduling processing unaware type of bearer Bureau. The scheduling unit is configured in a particular scheduling processing, the radio base station according to claim 1, assign a C-plane bearer to the main carrier, and wherein the assignment Turkey a U-plane bearer to the sub-carrier. The scheduling unit is configured in a particular scheduling process, assign the U-plane bearer for C-plane bearer and voice communications to the main carrier, and wherein the assignment Turkey a U-plane bearer for packet communications to the secondary carrier The radio base station according to claim 1. A wireless base station,
A scheduling unit configured to perform a scheduling process for a mobile station connected to a cell under the radio base station;
In a scheduling process for a mobile station performing CA (Carrier Aggregation), the scheduling unit detects the activation of the CA including the pico cell and sets the priority of the logical channel mapped to each bearer. If a specific scheduling process for determining a component carrier to which each bearer is allocated is performed and it is not detected that the CA including the pico cell is activated, the priority of the logical channel mapped to each bearer is determined. no line base station characterized in that it is configured to perform scheduling processing unaware degrees. A scheduling method in a radio base station,
In a scheduling process for a mobile station performing CA (Carrier Aggregation) in a cell under the radio base station,
A detecting step of detecting that the CA including the picocell is activated;
In the detection step, when it is detected that the CA including the pico cell is activated, a specific scheduling process for assigning a specific type of bearer to a specific component carrier is performed, and the detection step includes the pico cell. And a step of performing a scheduling process that is not conscious of the bearer type when it is not detected that the CA is activated . A scheduling method in a radio base station,
In a scheduling process for a mobile station performing CA (Carrier Aggregation) in a cell under the radio base station,
A detecting step of detecting that the CA including the picocell is activated;
In the detection step, when it is detected that the CA including the pico cell is activated, a specific carrier for allocating each bearer is determined based on the priority of the logical channel mapped to each bearer. Performing a scheduling process that is not conscious of the priority of the logical channel mapped to each bearer when the detection process does not detect that the CA including the pico cell has been activated. And a scheduling method.

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