JP2017208792A - User device and capability determination method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine MIMO capability for parameter calculation with the suppression of an increased signaling amount, when a user device supports a plurality of MIMO capabilities for a certain band combination.SOLUTION: In a mobile communication system which supports carrier aggregation, a user device which communicates with a base station includes: a receiver unit which receives from the base station the number of the antenna ports for each component carrier; and a determination unit which, when the user device supports a different plurality of MIMO capabilities in the band combination supported by the user device, determines the MIMO capability to maximize the number of the total maximum layers in the band combination, on the basis of the number of the antenna ports, received by the receiver unit, for each component carrier.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a user apparatus in a mobile communication system that supports carrier aggregation.

  LTE-Advanced employs carrier aggregation (CA) that performs communication using a plurality of carriers simultaneously. A carrier that is a basic unit in carrier aggregation is called a component carrier (CC).

  Carrier aggregation is classified into three scenarios as shown in FIGS. 1A to 1C according to the frequency arrangement of CC. FIG. 1A is an intra-band contiguous CA, which is a scenario in which continuous CCs are arranged in a band. This scenario is applied, for example, when a broadband allocation such as a 3.5 GHz band is performed. FIG. 1B is an inter-band non-contiguous CA in which a plurality of CCs of different bands are arranged. This scenario is applied, for example, when communication is performed using a plurality of carriers such as a 2 GHz band and a 1.5 GHz band. FIG. 1C is an intra-band non-contiguous CA, which is a scenario in which discontinuous CCs are arranged in the same band. This scenario is applied, for example, when the allocation of frequency bands to operators is fragmented.

  On the other hand, in the LTE (including LTE-Advanced) system, the user apparatus UE transmits its capability (Capability) to the base station eNB by a predetermined signaling message (UE-EUTRA-Capability), for example, when connecting to the network. (Non-Patent Document 1).

  In the notification of the capability information, the user apparatus UE notifies the base station eNB of a combination of bands (CA band combination, CA band combination) that the user apparatus UE supports in CA. Moreover, when the user apparatus UE can respond to a plurality of types of CA band combinations, the user apparatus UE notifies the base station eNB of all corresponding CA band combination patterns.

  An example of the structure of a message notifying the CA band combination is shown in FIG. As shown in FIG. 2, it is possible to notify the CA bandwidth class and the number of MIMO layers for each band combination and for each band in the UL / DL as shown in FIG. Although not shown in FIG. 2, for DL, it is possible to notify the number of CSI (Channel State Information) processes (supported CSI-Pro) that can be set by the UE for each band combination and for each band. Note that the number of CSI processes is the number of CSI processes used by the user apparatus UE when applying CoMP (Coordinated Multi-Point transmission / reception).

  The CA bandwidth class (CA bandwidth class) shown in FIG. 2 is a class defined by the table of FIG. 3, for example, and indicates the bandwidth that can be aggregated by the user apparatus UE, the number of CCs, and the like for each band.

  As described above, the user apparatus UE can notify the base station eNB of the number of MIMO layers supported by the user apparatus UE as capability information. Here, the number of MIMO layers of the user apparatus UE is set for each CC in each of UL and DL. Hereinafter, the number of MIMO layers means the number of DL MIMO layers.

  On the other hand, the capability of the number of MIMO layers in the user apparatus UE is notified to the base station eNB for each band. For example, in the case of Inter-band CA in FIG. 4A, the number of MIMO layers is notified in band 19 (class A), and the number of MIMO layers is notified in band 1 (class A). Also, in the case of Intra-band non-continuous CA in FIG. 4B, the number of MIMO layers 2 is notified in band 3 (class A), and the number of MIMO layers 4 in another band 3 (class A). Be notified. Note that the number of layers to be notified is the maximum number of layers supported by the user apparatus UE.

3GPP TS 36.331 V10.19.0 3GPP TS 36.212 V12.7.0

  Here, as described in Non-Patent Document 2, in the related art, the bit width (bit) of RI (Rank Indicator) which is one of channel state information (CSI) transmitted from the user apparatus UE to the base station eNB width) (which may be referred to as the number of bits) is determined for each CC (cell), for example, as follows.

  That is, when maxLayersMIMO (maximum number of layers) is notified from the base station eNB to the user apparatus UE, it is determined based on maxLayersMIMO. It is stipulated that the decision is made based on the number of MIMO layers notified in the field.

  When maxLayers MIMO is not notified, specifically, the user apparatus UE sets the minimum value among the maximum number of MIMO layers to be supported and the set number of antenna ports (the number of CSI-RS ports) as “maximum layer”. And the bit width of the RI is determined based on the maximum number of layers.

  Moreover, in the user apparatus UE and base station eNB in LTE, HARQ (Hybrid ARQ) control is performed in the HARQ entity of a MAC (Media Access Control) layer. For example, in HARQ control for downlink data in the user apparatus UE, ACK is returned to the base station eNB when decoding of the downlink data (TB: transport block) is successful, and NACK is transmitted to the base station when decoding fails. Return to eNB. Thus, in HARQ, retransmission control is performed by transmitting ACK / NACK. In HARQ, the user apparatus UE retains the data when decoding of the received data fails (when the data is incorrect), and the data retransmitted from the base station eNB and the retained data. And the synthesized data are decoded. Thereby, it is supposed to give a strong tolerance to errors. A storage unit (memory area) that holds the above data is called a soft buffer.

Here, in “5.1.4.1.2 Bit collection, selection and transmission” of Non-Patent Document 2, the value of Kc, which is a parameter used to calculate the soft buffer size (N _IR ) per TB, is , MaxLayersMIMO is not notified, it depends on whether the maximum number of MIMO layers supported by the user apparatus UE does not exceed 2 layers (whether it is 2 layers or less).

  By the way, in the prior art, maxLayersMIMO is notified only to intra-band contiguous CA, for example, inter-band CA and intra-band non-contiguous CA as shown in FIGS. 4 (a) and 4 (b). Will not be notified.

  Further, for example, in the band combination of 19A and 1A as shown in FIG. 4A, the user apparatus UE makes “(19A, 2 layers), (1A, 4 layers)” (referred to as band combination entry A). May correspond to a plurality of MIMO capabilities “(19A, 4 layers), (1A, 2 layers)” (referred to as band combination entry B). Note that in the case of the 19A and 1A band combination, maxLayersMIMO is not notified.

  In such a case, the user apparatus UE does not know which entry of a plurality of band combination entries (a plurality of MIMO capabilities) should be assumed in calculating the maximum number of layers for obtaining the RI bit width. Further, in this case, the user apparatus UE does not know which entry's number of layers should be assumed as the number of layers for calculating Kc. Therefore, there is a possibility that the RI bit width and Kc cannot be calculated appropriately.

  Here, if maxLayersMIMO is notified to Inter-band CA such as a band combination of 19A and 1A, the above problem can be solved. However, if maxLayersMIMO is notified in all cases of Inter-band CA, the signaling amount Increases, which is not preferable.

  Note that the above-described problem is not limited to the RI bit width but may also occur with respect to the bit width for transmitting other uplink control information (UCI). In addition, the above-described problem is not limited to the bit width such as the RI bit width and Kc, but may also occur for other parameters.

  The present invention has been made in view of the above points. When a user apparatus supports a plurality of MIMO capabilities for a certain band combination, an increase in signaling amount is suppressed, and MIMO for parameter calculation is performed. The aim is to provide a technology that allows the ability to be determined.

According to an embodiment of the present invention, a user apparatus that communicates with a base station in a mobile communication system that supports carrier aggregation,
A receiver that receives the number of antenna ports for each component carrier from the base station;
In the band combination supported by the user apparatus, when the user apparatus supports a plurality of different MIMO capabilities, the total in the band combination is based on the number of antenna ports for each component carrier received by the receiving unit. And a determining unit that determines a MIMO capability for maximizing the maximum number of layers.

  According to an embodiment of the present invention, when a user apparatus supports a plurality of MIMO capabilities for a certain band combination, the MIMO capability for parameter calculation is determined while suppressing an increase in signaling amount. It is possible to provide a technology that makes it possible.

It is a figure which shows the frequency arrangement | positioning example of a carrier aggregation, (a) shows Intra-band non-contiguous CA, (b) shows Inter-band non-continuous CA, (c) shows Intra-band non-continuous CA. Show. It is a figure which shows the structural example of the message which notifies CA band combination information. It is a table | surface which shows CA-BandwidthClass. It is a figure for demonstrating the capability notification of the number of MIMO layers, (a) shows the case of Inter-band CA, (b) shows the case of Intra-band non-contiguous CA. 1 is a configuration diagram of a mobile communication system according to an embodiment of the present invention. FIG. 6 is a sequence diagram showing an operation example 1; It is a figure for demonstrating a specific example. It is a figure which shows the example of RI bit width. It is a figure for demonstrating a specific example. It is a figure which shows the example of a specification change. It is a figure which shows the example of a specification change. It is a figure for demonstrating a specific example. FIG. 10 is a sequence diagram showing an operation example 2; It is a figure for demonstrating a specific example. It is a figure for demonstrating a specific example. It is a block diagram of the user apparatus UE. It is a block diagram of the base station eNB. It is a hardware block diagram of the user apparatus UE and the base station eNB.

  Embodiments of the present invention will be described below with reference to the drawings. The embodiment described below is only an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

  It is assumed that the mobile communication system according to the present embodiment is compatible with LTE. However, “LTE” used in the present specification has a broad meaning including LTE-Advanced and LTE-Advanced and subsequent systems (eg, 5G). In addition, the embodiment of the present invention is not limited to LTE but can be applied to other systems. For example, the embodiments of the present invention include SUPER 3G, IMT-Advanced, 4G, 5G, FRA (Future Radio Access), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband). , IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), or the next generation system extended based on these May be applied.

  Further, CA (carrier aggregation) in the present embodiment includes not only intra-eNB CA but also inter-eNB CA such as DC (Dual connectivity). Moreover, in this Embodiment, CC and a cell may be considered fundamentally synonymous and CC may be called a cell (more specifically, a serving cell).

(Whole system configuration)
FIG. 5 shows a configuration diagram of the mobile communication system according to the present embodiment. The mobile communication system according to the present embodiment is an LTE communication system, and includes a user apparatus UE and a base station eNB as shown in FIG. The user apparatus UE and the base station eNB can perform CA. The base station eNB can form a plurality of cells independently, or, for example, by remotely connecting an RRE (remote radio apparatus), a plurality of cells can be formed by the base station eNB main body and the RRE. Although FIG. 5 shows one user apparatus UE and one base station eNB, this is an example, and there may be a plurality of each. Moreover, the user apparatus UE may be provided with the capability (Dual Connectivity) which communicates with the some base station eNB simultaneously.

  When CA is performed, a PCell (Primary cell) that is a highly reliable cell that ensures connectivity and a SCell (Secondary cell) that is an ancillary cell are set for the user apparatus UE. First, the user apparatus UE can connect to the PCell and add an SCell as necessary. The PCell is a cell similar to a single cell that supports RLM (Radio Link Monitoring), SPS (Semi-Persistent Scheduling), and the like. The addition and deletion of the SCell is performed by RRC (Radio Resource Control) signaling. Immediately after being set for the user apparatus UE, the SCell is a cell that is in an inactive state (deactivated state), and thus can be communicated (schedulable) only when activated.

  Further, when performing dual connectivity, the user apparatus UE performs communication using radio resources of two physically different base stations eNB at the same time. Dual connectivity is a type of CA, also called Inter eNB CA (inter-base station carrier aggregation), and introduces Master-eNB (MeNB) and Secondary-eNB (SeNB). In DC, a cell group composed of cells (one or more) under the MeNB is defined as an MCG (Master Cell Group, master cell group), and a cell group composed of cells (one or a plurality) under the SeNB is defined as SCG ( (Secondary Cell Group, secondary cell group). A UL CC is set in at least one SCell of the SCGs, and a PUCCH is set in one of them. This SCell is called PSCell (primary SCell).

  In addition, the user apparatus UE includes a function of executing CoMP (Coordinated Multi-Point transmission / reception), and can notify capability information of the number of CSI processes.

  As one of basic operations of the user apparatus UE, there is transmission of uplink control information (hereinafter referred to as UCI). UCI includes ACK / NACK (hybrid ARQ delivery confirmation), scheduling request, channel state information (hereinafter, CSI), and the like. CSI includes CQI, PMI, RI, and the like. In the present embodiment, attention is paid particularly to transmission of RI in CSI. However, the technique of the present embodiment can also be applied to UCI other than RI.

  The CSI report includes a periodic report and an aperiodic report. PUCCH is usually used for periodic reporting. However, when there is data transmission by PUSCH at periodic reporting timing, PUSCH may be used. Moreover, aperiodic reporting is performed by PUSCH based on the request | requirement in the scheduling grant from the base station eNB.

  The target of CSI reporting is for each downlink CC (cell). For example, in downlink CA consisting of downlink CC1 and downlink CC2, the user apparatus UE obtains RI1 by measuring CSI-RS received in downlink CC1, reports RI1 to the base station eNB as RI for downlink CC1, and downlink CC2 RI2 is obtained from the measurement of the CSI-RS received at, and RI2 is reported to the base station eNB as RI for the downlink CC2.

(Operation example 1)
With reference to FIG. 6, an example of an operation sequence in the present embodiment will be described.

  In step S101, the user apparatus UE transmits UE capability information to the base station eNB. The UE capability information includes CA band combination information.

  The CA band combination information includes the maximum number of DL MIMO layers supported by the user apparatus UE for each band (hereinafter, the number of DL MIMO layers is described as the number of MIMO layers). For example, when the band class includes B and C and a plurality of CCs are included per band, the maximum number of MIMO layers supported by the user apparatus UE is included for each CC in the band. When the class of the band is A, the number of MIMO layers notified to the band becomes the number of MIMO layers in one CC of the band. That is, when the class of the band is A, the number of MIMO layers notified to the band corresponds to the number of MIMO layers of the CC of the band.

  In the example described below, the CA executed by the user apparatus UE is assumed to be an inter-band CA, and basically, maxLayers MIMO is not notified. Note that maxLayersMIMO is notified in a specific case as described in the operation example 2, or when 4-layer MIMO is performed in the transmission mode 3 or 4.

  In the present embodiment, the user apparatus UE supports a set of a plurality of different MIMO layers (referred to as a MIMO capability) for one band combination, and the capability information indicating this is sent to the base station. eNB is notified. Specifically, for example, as illustrated in FIG. 7, the user apparatus UE supports “(band 41A, 4 layers), (band 42A, 2 layers)” as the band combination entry 1, and the band combination entry 2 "(Band 41A, 2 layers), (Band 42A, 4 layers)" is supported.

  In step S102 of FIG. 6, for example, the base station eNB includes the number of antenna ports for each CC in the set band combination (CSI− in the present embodiment) included in the setting information (eg, radioResourceConfigDedicated) transmitted by the RRC signal. RS port number) is transmitted to the user apparatus UE. In step S102, the CA of the band combination may be set.

  In step S103, the user apparatus UE sets the maximum number of layers for each CC based on the number of MIMO layers of each CC of each entry (MIMO capability) in the band combination notified in step S101 and the set number of antenna ports. And determine the RI bit width.

  In step S104, the user apparatus UE determines Kc used for calculating the soft buffer size based on the maximum number of layers for each CC used for calculating the RI bit width determined in step S103, and uses the determined Kc. To determine the soft buffer size.

<Details of determination of RI bit width and Kc>
Hereinafter, the determination of the RI bit width in step S103 and the determination method of Kc in step S104 will be described in detail.

  As a basic operation, when maxLayers MIMO is not notified, the maximum number of MIMO layers supported by the user apparatus UE and the minimum value among the set number of antenna ports (the number of CSI-RS ports) are set as the “maximum number of layers”. The RI bit width is determined based on the maximum number of layers. More specifically, for example, according to Table 5.2.2.6.1-2 of Non-Patent Document 2 illustrated in FIG. 8, for example, if the maximum number of layers is 4 and the number of antenna ports is 4, The RI bit width is determined to be 2.

  However, in the example of FIG. 7 assumed in the operation example 1, there are a plurality of entries (MIMO capability) in the bands (each of 41 and 42) supported by the user apparatus UE and are not uniquely determined.

  Therefore, in the present embodiment, as described above, when the user apparatus UE supports a plurality of different MIMO capabilities in the supported band combination (for example, the band 41 and the band 42), the user apparatus UE In consideration of the number of antenna ports notified from the base station eNB to each CC of each band of the band combination, the maximum number of layers for calculating the RI bit width is the total, and the MIMO layer that is the maximum in the band combination Select ability.

  A specific example will be described with reference to FIG. FIG. 9 is based on the example shown in FIG. The example of FIG. 9 illustrates an example in which 4 ports are set for the CC of the band 41 and 2 ports are set for the CC of the band 42. If “the minimum value of the number of MIMO layers and the number of antenna ports is set to“ the maximum number of layers ”” is applied to each band combination entry, the band combination entry 1 in FIG. The maximum number of layers is 4, and the maximum number of layers is 2 for the CC of the band 42. Therefore, the total maximum number of layers is 6.

  On the other hand, in the band combination entry 2 of FIG. 9, the maximum number of layers is 2 for the CC of the band 41 and the maximum number of layers is 2 for the CC of the band 42. Therefore, the total maximum number of layers is 4.

  Therefore, the user apparatus UE selects the band combination entry 1 that maximizes the maximum number of layers, and determines the RI bit width using the combination of the number of MIMO layers. When the table of FIG. 8 is used, the RI bit width of the CC of the band 41 is determined to be 2, and the RI bit width of the CC of the band 42 is determined to be 1.

  Next, determination of Kc used for calculating the soft buffer size will be described. In the present embodiment, when the user apparatus UE supports a plurality of different MIMO capabilities in the supported band combination (eg, band 41 and band 42), the user apparatus UE is required to calculate the RI bit width. Kc is determined based on the maximum number of layers of each CC in the entry selected in (MIMO capability). That is, as described in 5.1.4.1.2 of Non-Patent Document 2, in a specific situation, whether or not the maximum number of layers of the CC exceeds 2 for a certain CC It is determined. Then, the soft buffer size is calculated based on the determined Kc.

FIG. 10 shows a specification change example (excerpt) of the part related to the selection of the MIMO capability. FIG. 10 shows a change from Non-Patent Document 2, and the changed (added) portion is underlined. As shown in FIG. 10, “ If different downlink MIMO capabilities are supported for the same band combination, the UE shall select the downlink MIMO capability which maximizes the maximum number of layers in total based on the configured number of CSI-RS ports. Have been added.

FIG. 11 shows a specification change example (excerpt) of the part relating to the determination of Kc. FIG. 11 shows a change from Non-Patent Document 2, and the changed (added) portion is underlined. As shown in FIG. 11, `` if the UE is capable of supporting no more than a maximum of two spatial layers for the DL cell in the transmission mode configured for the UE, or if the configured maximum number of layers indicated by the maxLayersMIMO-r10 The underlined part shown in “field is no more than two, or if the maximum number of layers determined for RI bitwidths is no more than two ” is added. For example, the user apparatus UE determines to calculate the RI bit width when “a maximum of two spatial layers for the DL cell” is not uniquely determined and maxLayersMIMO is not notified (for example, in the case of FIG. 7). Kc is determined based on the maximum number of layers of each CC.

(Operation example 2)
Next, the operation example 2 will be described focusing on portions different from the operation example 1. Also in the operation example 2, basically, when the user apparatus UE supports a plurality of different MIMO capacities in the supported band combination (eg, the band 41 and the band 42), each CC of each band of the band combination is supported. In consideration of the number of antenna ports (the number of CSI-RS ports) notified from the base station eNB, the maximum MIMO capacity for calculating the RI bit width is maximized in the band combination. select. However, the MIMO capability that maximizes the total maximum number of layers in a band combination may not be uniquely determined. The operation example 2 explains the operation in that case.

  The case where the MIMO capability that maximizes the total maximum number of layers is not uniquely determined is, for example, the case shown in FIG. In the example of FIG. 12, when the user apparatus UE notifies the base station eNB of the same band combination as in FIG. 7, 4 ports are set for the CC of the band 41 and 4 ports are also set for the CC of the band 42. An example in which is set is shown.

  In this case, in the band combination entry 1, the maximum number of CC layers in the band 41 is 4, the maximum number of CC layers in the band 42 is 2, and the total is 6. In the band combination entry 2, the maximum number of CC layers in the band 41 is 2, the maximum number of CC layers in the band 42 is 4, and the total is 6. Therefore, the sum is the same between the band combination entries (MIMO capabilities), and the user apparatus UE cannot determine which entry should be selected.

  Therefore, in such a case, for example, the base station eNB reports maxLayers MIMO to the user apparatus UE for each CC (cell) of each band, and the user apparatus UE maximizes the value notified by the maxLayers MIMO. By using it as the number of layers, the RI bit width and Kc are determined.

  The sequence in the operation example 2 will be described with reference to FIG. First, in the same manner as in operation example 1, CA combination information is notified from the user apparatus UE to the base station eNB in step S101. In step S102, the number of antenna ports for each CC is notified from the base station eNB to the user apparatus UE.

  However, in the operation example 2, the base station eNB uses the band combination (eg, FIG. 7) supported by the user apparatus UE and the number of antenna ports for each CC set in the user apparatus UE in the same manner as described above. The total of the maximum number of layers for calculating the RI bit width is obtained for each combination entry. Then, when only one having the maximum sum among a plurality of band combination entries can be selected (example: FIG. 9), maxLayers MIMO is not notified as in the first operation example.

  On the other hand, when the maximum sum among the plurality of band combination entries cannot be determined (for example, FIG. 12), maxLayers MIMO for each CC is notified to the user apparatus UE together with the number of antenna ports for each CC (step S102). ). For example, in the case of FIG. 12, 4 is notified as the max Layers MIMO of the CC of the band 41, and 2 is notified as the max Layers MIMO of the CC of the band 42.

  In step S103, the RI bit width is determined based on maxLayersMIMO. That is, for each CC, the RI layer width is determined from the table of FIG. 8, for example, using maxLayers MIMO as the maximum number of layers.

  In step S104, Kc is determined based on maxLayersMIMO or the maximum number of layers of each CC determined for RI bit width calculation. The specification change example shown in FIG. 11 can also be applied to the operation of the operation example 2.

(Operation example 3)
In the operation example 2 described above, in the case where the MIMO capability that maximizes the total maximum number of layers in the band combination is not uniquely determined, the base station eNB may maxLayersMIMO is notified, and the user apparatus UE uses the value notified in maxLayersMIMO as the maximum number of layers to determine the RI bit width and Kc. As a solution when the MIMO capability that maximizes the maximum number of maximum layers in the band combination is not uniquely determined, it is possible to take a method of not reporting maxLayers MIMO as well as a method of notifying maxLayers MIMO as in Operation Example 2. is there. This will be described as operation example 3.

  The entire sequence in the operation example 3 is the same as the sequence in the operation example 1 shown in FIG. In the operation example 3, the RI bit width determination process in step S103 in the sequence shown in FIG. However, when the MIMO capability that maximizes the total maximum number of layers in the band combination is uniquely determined (example: case shown in FIG. 9), the operation example 3 is the same as the operation example 1.

  Hereinafter, a method of determining the RI bit width in the operation example 3 when the MIMO capability that maximizes the total maximum number of layers in the band combination is not uniquely determined will be described.

  In such a case, in the operation example 3, the user apparatus UE sets the maximum value among the maximum number of layers for each CC in the total MIMO capability (all band combination entries) of the corresponding band combination in all CCs (each CC). Assuming the maximum number of layers, the RI bit width of each CC is calculated using the maximum number of layers. The above-mentioned “per CC” may be rephrased as “per band” in the case of one band and one CC (eg, FIG. 7). The “maximum number of layers” is the minimum value of the number of MIMO layers and the number of antenna ports as described above. A specific example will be described below.

  For example, as in the example shown in FIG. 12, when 4 ports are set for the CC of the band 41 and 4 ports are set for the CC of the band 42, the band 41 in the band combination entry 1 is set. The maximum number of CC layers is 4, the maximum number of CCs in the band 42 is 2, and the total is 6. In the band combination entry 2, the maximum number of CC layers in the band 41 is 2, the maximum number of CC layers in the band 42 is 4, and the total is 6. That is, the sum is the same between the band combination entries (MIMO capabilities). Therefore, in this case, the RI bit width is calculated by using 4 which is the maximum value among the calculated maximum number of layers (4, 2, 2, 4) of all CCs as the maximum number of layers of each CC. . In this example, since the number of ports is 4, when the table of FIG. 8 is used, the RI bit width of each CC is calculated as 2.

  Further, as shown in the example of FIG. 14, when 8 ports are set for the CC of the band 41 and 8 ports are also set for the CC of the band 42, the band combination entry 1 includes the band 41. The maximum number of CC layers is 4, the maximum number of CCs in the band 42 is 2, and the total is 6. In the band combination entry 2, the maximum number of CC layers in the band 41 is 2, the maximum number of CC layers in the band 42 is 4, and the total is 6. That is, the sum is the same between the band combination entries (MIMO capabilities). Therefore, also in this case, the RI bit width is calculated by using 4 which is the maximum value among the calculated maximum number of layers (4, 2, 2, 4) of all CCs as the maximum number of layers of each CC. To do.

  Next, as in the example illustrated in FIG. 15, when the MIMO capability of the user apparatus UE is (band 41, band 42) = {8 layers, 4 layers}, {4 layers, 8 layers}, Consider a case where 4 ports are set for the CC and 4 ports are set for the CC of the band 42. In this case, in the band combination entry 1, the maximum number of CC layers in the band 41 is 4, the maximum number of CC layers in the band 42 is 4, and the total is 8. In the band combination entry 2, the maximum number of CC layers in the band 41 is 4, the maximum number of CC layers in the band 42 is 4, and the total is 8. That is, the sum is the same between the band combination entries (MIMO capabilities). Therefore, also in this case, the RI bit width is calculated by using 4 which is the maximum value among the calculated maximum number of layers (4, 4, 4, 4) of all CCs as the maximum number of layers of each CC. To do.

  Regarding Kc, as in the first operation example, the user apparatus UE determines the Kc of each CC based on the maximum number of layers used for RI bit width calculation.

  As described above, in the present embodiment, notification of maxLayers MIMO can be minimized. In particular, in operation examples 1 and 3, the notification of maxLayers MIMO does not have to be performed. Therefore, when the user apparatus UE supports a plurality of MIMO capabilities for a certain band combination, it is possible to determine the MIMO capability for parameter calculation while suppressing an increase in the amount of signaling.

  Note that the method for determining the MIMO capability described in this embodiment can be applied to the case of determining the CSI process capability by replacing the “number of MIMO layers” in this embodiment with the “number of CSI processes”.

(Device configuration)
Next, main configurations of the user apparatus UE and the base station eNB that can execute the processes described so far (including the operation example 1, the operation example 2, and the operation example 3) will be described.

  First, in FIG. 16, the block diagram of the user apparatus UE which concerns on this Embodiment is shown. As illustrated in FIG. 16, the user apparatus UE includes a UL signal transmission unit 101, a DL signal reception unit 102, an RRC management unit 103, and a parameter determination unit 104. FIG. 16 shows only functional units particularly relevant to the embodiment of the present invention in the user apparatus UE. Further, the functional configuration shown in FIG. 16 is merely an example. As long as the operation according to the present embodiment can be performed, the function classification and the name of the function unit may be anything. Further, the user apparatus UE may have a function of performing all the operations of the operation examples 1, 2, and 3, or a function of performing any one of the operation examples 1, 2, and 3. Alternatively, it may have a function of performing any two of the operation examples 1, 2, and 3.

  The UL signal transmission unit 101 includes a function of generating and wirelessly transmitting various physical layer signals from higher layer signals to be transmitted from the user apparatus UE. The DL signal receiving unit 102 includes a function of wirelessly receiving various signals from the base critical station eNB and acquiring a higher layer signal from the received physical layer signal. Each of the UL signal transmission unit 101 and the DL signal reception unit 102 includes a function of executing CA that performs communication by bundling a plurality of CCs. The DL signal receiving unit 102 includes a function of measuring a reference signal and determining CSI such as RI, and the UL signal transmitting unit 101 includes a function of transmitting CSI such as RI. In addition, the DL signal receiving unit 102 and the UL signal transmitting unit 101 include a function of performing HARQ control related to data reception using a soft buffer having a size determined by the parameter determining unit 104.

  Each of the UL signal transmission unit 101 and the DL signal reception unit 102 is assumed to include a packet buffer and perform layer 1 (PHY) and layer 2 (MAC, RLC, PDCP) processing. However, it is not limited to this.

  The RRC management unit 103 transmits / receives an RRC message to / from the base station eNB via the UL signal transmission unit 101 / DL signal reception unit 102, and processes such as setting / change / management of CA information, configuration change, etc. Includes the ability to In addition, the RRC management unit 103 holds information on the capability of the user apparatus UE, creates an RRC message that notifies the capability information, and transmits the RRC message to the base station eNB via the UL signal transmission unit 101.

  The parameter determination unit 104 uses the method described in this embodiment to determine the MIMO capability, the maximum number of layers, the maximum number of CSI processes, the RI bit width calculation, the determination of Kc, the soft buffer size Perform calculations.

  FIG. 17 shows a functional configuration diagram of the base station eNB according to the present embodiment. As illustrated in FIG. 17, the base station eNB includes a DL signal transmission unit 201, a UL signal reception unit 202, an RRC management unit 203, and a scheduling unit 204. FIG. 17 shows only main functional units in the base station eNB. In addition, the functional configuration illustrated in FIG. 17 is merely an example. As long as the operation according to the present embodiment can be performed, the function classification and the name of the function unit may be anything. The base station eNB may be a single base station eNB or may be either a MeNB or a SeNB when performing DC by configuration. Further, the base station eNB may have a function of performing all the operations of the operation examples 1, 2, and 3, or a function of performing any one of the operation examples 1, 2, and 3. Alternatively, it may have a function of performing any two of the operation examples 1, 2, and 3.

  The DL signal transmission unit 201 includes a function of generating and wirelessly transmitting various physical layer signals from higher layer signals to be transmitted from the base station eNB. The UL signal receiving unit 202 includes a function of wirelessly receiving various signals from each UE and acquiring a higher layer signal from the received physical layer signal. Each of the DL signal transmission unit 201 and the UL signal reception unit 202 includes a function of executing CA that performs communication by bundling a plurality of CCs. Further, the DL signal transmission unit 201 and the UL signal reception unit 202 may include a radio communication unit installed remotely from the main body (control unit) of the base station eNB, like RRE.

  Each of the DL signal transmission unit 201 and the UL signal reception unit 202 includes a packet buffer, and is assumed to perform layer 1 (PHY) and layer 2 (MAC, RLC, PDCP) processing (however, this is not the only case). Not.)

  The RRC management unit 203 transmits / receives an RRC message to / from the user apparatus UE via the DL signal transmission unit 201 / UL signal reception unit 202, and performs processing such as CA setting / change / management, configuration change, and the like. Includes functionality. In addition, the RRC management unit 203 receives capability information from the user apparatus UE via the UL signal reception unit 202, holds the capability information, and sets CA for the user apparatus UE based on the capability information. Can be implemented. Further, as described as the operation of the base station eNB in the present embodiment, the RRC management unit 203 determines the number of antenna ports to be set in the user apparatus UE, determines whether or not to notify the user apparatus UE of maxLayers MIMO, and maxLayersMIMO. And a function of notifying the number of antenna ports / maxLayers MIMO.

  Scheduling unit 204 performs scheduling for each cell for user apparatus UE that performs CA, creates PDCCH allocation information, and instructs DL signal transmission unit 201 to transmit PDCCH including the allocation information. Including.

<Hardware configuration>
The above block diagrams (FIGS. 16 and 17) show functional unit blocks. These functional blocks (components) are realized by any combination of hardware and / or software. Further, the means for realizing each functional block is not particularly limited. That is, each functional block may be realized by one device physically and / or logically combined with other functional blocks, or two or more devices physically and / or logically separated may be directly connected. It may be realized by a plurality of devices that are connected manually and / or indirectly (for example, wired and / or wirelessly).

  For example, each of the user apparatus UE and the base station eNB in the embodiment of the present invention may be realized by a computer that performs the processing in the present embodiment. FIG. 18 is a diagram illustrating an example of the hardware configuration of each of the user apparatus UE and the base station eNB according to the embodiment of the present invention. Since the base station eNB and the user apparatus UE have the same configuration as hardware, these hardware configurations are shown in one figure (FIG. 18).

  As shown in FIG. 18, the above-described user apparatus UE and base station eNB physically include a processor 1001, a memory 1002, a storage 1003, a communication apparatus 1004, an input apparatus 1005, an output apparatus 1006, a bus 1007, and the like. It may be configured as a device.

  In the following description, the term “apparatus” can be read as a circuit, a device, a unit, or the like. The hardware configuration of the user apparatus UE and the base station eNB may be configured to include one or a plurality of each device (each unit) illustrated in the figure, or may be configured not to include some devices. Good.

  Each function in the user apparatus UE and the base station eNB reads predetermined software (program) on hardware such as the processor 1001 and the memory 1002, so that the processor 1001 performs calculation and controls communication by the communication apparatus 1004. This is realized by controlling data reading and / or writing in the memory 1002 and the storage 1003.

  For example, the processor 1001 controls the entire computer by operating an operating system. The processor 1001 may be configured by a central processing unit (CPU) including an interface with a peripheral device, a control device, an arithmetic device, a register, and the like.

  Further, the processor 1001 reads a program (program code), a software module, and data from the storage 1003 and / or the communication device 1004 to the memory 1002, and executes various processes according to these. As the program, a program that causes a computer to execute at least a part of the operations described in the above embodiments is used. For example, the UL signal transmission unit 101, the DL signal reception unit 102, the RRC management unit 103, and the parameter determination unit 104 of the user apparatus UE may be realized by a control program stored in the memory 1002 and operating on the processor 1001. Further, for example, the DL signal transmission unit 201, the UL signal reception unit 202, the RRC management unit 203, and the scheduling unit 204 of the base station eNB may be realized by a control program stored in the memory 1002 and operating on the processor 1001.

  Although the above-described various processes have been described as being executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. Note that the program may be transmitted from a network via a telecommunication line.

  The memory 1002 is a computer-readable recording medium, for example, ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), RAM (Random Access Memory 1). It may be constituted by. The memory 1002 may be called a register, a cache, a main memory (main storage device), or the like. The memory 1002 can store a program (program code), software module, data, and the like that can be executed to perform the processing described in this embodiment.

  The storage 1003 is a computer-readable recording medium such as an optical disc such as a CD-ROM (Compact Disc ROM), a hard disc drive, a flexible disc, a magneto-optical disc (eg, a compact disc, a digital versatile disc, a Blu-ray). (Registered trademark) disk, smart card, flash memory (eg, card, stick, key drive), floppy (registered trademark) disk, magnetic strip, and the like. The storage 1003 may be referred to as an auxiliary storage device. The storage medium described above may be, for example, a database, server, or other suitable medium including the memory 1002 and / or the storage 1003.

  The communication device 1004 is hardware (transmission / reception device) for performing communication between devices via a wired and / or wireless network, and is also referred to as a network device, a network controller, a network card, a communication module, or the like. For example, the DL signal reception unit 102 and the UL signal transmission unit 101 of the user apparatus UE may be realized by the communication apparatus 1004. Also, the DL signal transmission unit 201 and the UL signal reception unit 202 of the base station eNB may be realized by the communication device 1004.

  The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, or the like) that accepts an external input. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that performs output to the outside. The input device 1005 and the output device 1006 may have an integrated configuration (for example, a touch panel).

  Each device such as the processor 1001 and the memory 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be configured with a single bus or may be configured with different buses between apparatuses.

  In addition, the base station eNB and the user equipment UE are a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), an FPGA (GigaFragable Logic Device), and an FPGA. Hardware may be configured, and a part or all of each functional block may be realized by the hardware. For example, the processor 1001 may be implemented by at least one of these hardware.

(Summary of embodiment)
As described above, according to the present embodiment, a user apparatus that communicates with a base station in a mobile communication system that supports carrier aggregation, and that receives a number of antenna ports for each component carrier from the base station In the band combination supported by the user apparatus, when the user apparatus supports a plurality of different MIMO capabilities, the band combination is based on the number of antenna ports for each component carrier received by the reception unit. And a determining unit that determines a MIMO capability that maximizes the total maximum number of layers.

  With the above configuration, when the user apparatus supports a plurality of MIMO capabilities for a certain band combination, it is possible to suppress the increase in the amount of signaling and determine the MIMO capability for parameter calculation.

  The determining unit determines the maximum number of layers for each component carrier based on the determined MIMO capability, and based on the maximum number of layers, determines the bit width or soft buffer size for uplink control information transmission The parameter value used for calculation may be determined. With this configuration, an increase in the amount of signaling can be suppressed, and the value of a parameter used to calculate the bit width or the soft buffer size for transmitting uplink control information can be clearly determined.

  The determining unit determines the bit width based on the maximum number of layers for each component carrier received from the base station by the receiving unit when the MIMO capability for maximizing the total maximum number of layers is not fixed to one. Alternatively, the value of the parameter may be determined. With this configuration, even when the MIMO capability for maximizing the total maximum number of layers is not fixed to one, the bit width for transmission of uplink control information or the value of a parameter used for calculating the soft buffer size is set. Can be determined clearly.

  The determining unit may calculate a sum of smaller values of the maximum number of layers and the number of antenna ports in a certain MIMO capability as the total maximum number of layers in the MIMO capability. With this configuration, the total maximum number of layers in the MIMO capability can be calculated appropriately.

  Although the embodiments of the present invention have been described above, the disclosed invention is not limited to such embodiments, and those skilled in the art will understand various variations, modifications, alternatives, substitutions, and the like. Will. Although specific numerical examples have been described in order to facilitate understanding of the invention, these numerical values are merely examples and any appropriate values may be used unless otherwise specified. The classification of items in the above description is not essential to the present invention, and the items described in two or more items may be used in combination as necessary. It may be applied to the matters described in (if not inconsistent). The boundaries between functional units or processing units in the functional block diagram do not necessarily correspond to physical component boundaries. The operations of a plurality of functional units may be physically performed by one component, or the operations of one functional unit may be physically performed by a plurality of components.

  Further, the order of processing procedures, sequences, and the like of each aspect / embodiment described in the present specification may be changed as long as there is no contradiction. For example, the methods described herein present the elements of the various steps in an exemplary order and are not limited to the specific order presented.

  Input / output information or the like may be stored in a specific location (for example, a memory) or may be managed by a management table. Input / output information and the like can be overwritten, updated, or additionally written. The output information or the like may be deleted. The input information or the like may be transmitted to another device.

  The notification of the predetermined information (for example, notification of “being X”) is not limited to explicitly performed, and may be performed implicitly (for example, notification of the predetermined information is not performed). .

  Information, signals, etc. described herein may be represented using any of a variety of different technologies. For example, data, commands, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description are voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any of these May be represented by a combination of

  Note that the terms described in this specification and / or terms necessary for understanding this specification may be replaced with terms having the same or similar meaning. For example, the message may be a signal.

  In addition, information, parameters, and the like described in this specification may be represented by absolute values, may be represented by relative values from a predetermined value, or may be represented by other corresponding information. . Further, the reference signal may be abbreviated as RS (Reference Signal), and may be referred to as a pilot depending on an applied standard.

  The present invention is not limited to the above embodiments, and various modifications, modifications, alternatives, substitutions, and the like are included in the present invention without departing from the spirit of the present invention.

UE user apparatus eNB base station 101 UL signal transmission section 102 DL signal reception section 103 RRC management section 104 parameter determination section 201 DL signal transmission section 202 UL signal reception section 203 RRC management section 204 scheduling section 1001 processor 1002 memory 1003 storage 1004 communication apparatus 1005 Input device 1006 Output device

Claims (5)

A user apparatus that communicates with a base station in a mobile communication system that supports carrier aggregation,
A receiver that receives the number of antenna ports for each component carrier from the base station;
In the band combination supported by the user apparatus, when the user apparatus supports a plurality of different MIMO capabilities, the total in the band combination is based on the number of antenna ports for each component carrier received by the receiving unit. And a determining unit that determines a MIMO capability that maximizes the maximum number of layers. The determining unit determines the maximum number of layers for each component carrier based on the determined MIMO capability, and based on the maximum number of layers, determines the bit width or soft buffer size for uplink control information transmission The user device according to claim 1, wherein a parameter value used for calculation is determined. The determining unit determines the bit width based on the maximum number of layers for each component carrier received from the base station by the receiving unit when the MIMO capability for maximizing the total maximum number of layers is not fixed to one. Or the value of the parameter is determined. The user apparatus according to claim 2, wherein: The said determination part calculates the sum total of the smaller value of the maximum number of layers and the number of antenna ports in a certain MIMO capability as the said maximum number of maximum layers in the said MIMO capability. 4. The user device according to claim 1. A capability determination method executed by a user apparatus that communicates with a base station in a mobile communication system that supports carrier aggregation, wherein the receiving step receives the number of antenna ports for each component carrier from the base station;
In the band combination supported by the user apparatus, when the user apparatus supports a plurality of different MIMO capabilities, the total in the band combination is based on the number of antenna ports for each component carrier received in the reception step. And a determination step for determining a MIMO capability for maximizing the maximum number of layers.

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