JP2018182359A - Base station device, terminal device, control method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique to make it possible to collectively notify a plurality of terminal devices of control information when preemption is performed using radio resources allocated to the terminal devices.SOLUTION: When a base station device transmits data (preemption) to a terminal device for URLLC using part of radio resources already allocated to a plurality of terminal devices while communicating with the terminal devices for eMBB, the base station device selects an individual radio resource or a common radio resource for notification of control information on the preemption (S63). The base station device uses the selected radio resource from the individual radio resource and common radio resource to notify the terminal device of the control information on the preemption (S64).SELECTED DRAWING: Figure 6

Description

  The present invention relates to a radio resource allocation technique of a radio communication system.

  The Third Generation Partnership Project (3GPP) is currently in the process of standardizing a fifth generation cellular communication system called New Radio (NR). In NR, in addition to high-speed and high-capacity communication (eMBB: enhanced mobile broadband), it is assumed that highly reliable and low-latency communication (URLLC: ultra-reliable and low latency communication) is also supported. In particular, in order to realize URLLC in downlink, a mechanism called preemption in which URLLC interrupts during eMBB communication has been considered (see Non-Patent Documents 1 and 2).

Samsung, Preemption-based multiplexing between eMBB and URLLC for DL, 3GPP TSG-RAN WG1 NR Ad-Hoc Meeting, R1-1700966, January 16-20, 2017 Samsung, Evaluation Results of Superposition for Multiplexing eMBB and URLLC, 3GPP TSG-RAN WG1 NR Ad-Hoc Meeting, R1-1700969, January 16-20, 2017

  In preemption, the reception performance of the eMBB terminal device is affected by thinning data to be transmitted to the eMBB terminal device. Therefore, it is considered to notify control information related to preemption from a base station apparatus to an eMBB terminal apparatus (see Non-Patent Document 1). However, when preemption is performed using radio resources allocated to a plurality of terminal devices for eMBB, when the control information is notified from the base station device for each terminal device, the radio resources are wasted for the notification. , The frequency utilization efficiency decreases.

  The present invention has been made in view of the above problems. The present invention provides a technique for enabling collective notification of control information to a plurality of terminal devices when preemption is performed using radio resources allocated to the plurality of terminal devices. It is an object.

  A base station apparatus according to an aspect of the present invention uses a part of radio resources in radio resources already allocated to the first and second terminals during communication with the first and second terminals. Determining means for determining transmission processing for transmitting data addressed to the third terminal apparatus, and transmitting data to the third terminal apparatus according to the determination by the determining means using the part of the radio resources Transmission means, individual radio resources for which the first and second terminals can respectively demodulate, and common radio for which both the first and second terminals can demodulate in common And notification means for notifying the first and second terminals of control information related to the transmission process using any radio resource with the resource.

  A terminal apparatus according to an aspect of the present invention receives data from the base station apparatus using a radio resource allocated from the base station apparatus, and stores the received data in a storage unit, and the terminal Related to the transmission processing notified from the base station apparatus when transmission processing of data to another terminal apparatus is performed using a part of radio resources in a radio resource already allocated to the apparatus A separate radio resource that the terminal device can demodulate to receive control information, and a common radio resource that can be commonly demodulated by a plurality of terminal devices including the terminal device In both, receiving means for attempting to receive the control information and performing demodulation processing of data stored in the storage means according to the control information received by the receiving means And having a demodulating means.

  According to the present invention, when preemption is performed using radio resources allocated to a plurality of terminal devices, control information can be collectively notified to the plurality of terminal devices.

Diagram showing a configuration example of a wireless communication system Figure showing an example of interrupt for communication with a terminal for eMBB Block diagram showing an example of hardware configuration of a base station apparatus and a terminal apparatus Block diagram showing an example of functional configuration of a base station apparatus Block diagram showing an example of functional configuration of a terminal device Flow chart showing procedure of processing executed by base station apparatus A diagram showing an example of transmission of control information related to preemption A diagram showing an example of transmission of control information related to preemption Diagram showing an example of generation of control information corresponding to a radio resource to be used Flow chart showing procedure of processing executed by terminal device for eMBB A figure showing an example of transmission of control information related to preemption when MU-MIMO is used. A diagram showing an example of transmission of control information related to preemption based on an operation state of a terminal device A diagram showing an example of transmission of control information related to preemption based on an operation state of a terminal device

  Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. In the following drawings, components not necessary for the description of the embodiment will be omitted from the drawings.

First Embodiment
<System configuration>
FIG. 1 is a diagram showing an example of a configuration of a wireless communication system according to the first embodiment. The wireless communication system of the present embodiment is configured to include a base station apparatus 10 forming a cell 100 and a plurality of terminal apparatuses 11 to 13. In the example of FIG. 1, although three terminal devices 11 to 13 exist in the cell 100 formed by the base station device 10, any number of terminal devices may exist in the cell 100.

  Communication between the base station apparatus 10 and the terminal apparatuses 11 to 13 is performed by using the radio resources allocated by the base station apparatus 10 to the terminal apparatuses 11 to 13. The base station apparatus 10 allocates radio resources for uplink communication in the direction from the terminal apparatuses 11 to 13 to the base station apparatus 10 and downlink communication in the direction from the base station apparatus 10 to the terminal apparatuses 11 to 13, respectively. Do. Radio resources to be allocated may be specified, for example, by time and frequency, and may be further specified by space (spatial layer) if spatial multiplexing is used.

  In the present embodiment, the terminal devices 11 and 12 are an example of a terminal device (first terminal device) that performs high-speed large-capacity communication (eMBB), and the terminal device 13 performs high-reliability low-delay communication (URLLC). ) Is an example of a terminal device (second terminal device) that performs. The terminal devices 11 to 13 may be mobile devices such as smartphones and tablet terminals. The terminal device 13 may be, for example, a car (a communication device mounted on a car), because a service such as automatic driving or telemedicine may be assumed for the URLLC service.

  When the base station apparatus 10 starts communication with the terminal device for URLLC (for example, the terminal device 13) during communication with the terminal device for eMBB (for example, the terminal devices 11 and 12), the terminal device for eMBB has already been started. There are cases where communication with a terminal device for URLLC is performed (that is, communication with a terminal device for URLLC is interrupted in communication with a terminal device for eMBB) using a part of the allocated wireless resources.

  Here, FIG. 2 is a diagram showing an example of an interrupt for communication with the eMBB terminal device, and the terminal device being the URLLC terminal device during communication with the terminal device 11 being the eMBB terminal device. An example in which an interrupt by communication with T.12 is performed is shown. In the example of FIG. 2, the base station apparatus 10 allocates the radio resource 20 to the terminal apparatus 11 by scheduling data transmission to the terminal apparatus 11, and uses the radio resource 20 to allocate data to the terminal apparatus 11. Start sending. The result of the scheduling is notified from the base station apparatus 10 to the terminal apparatus 11 as the scheduling information 21. The notification of the scheduling information 21 is not limited to the area shown in FIG. 2 in the time-frequency domain, and may be performed using radio resources of other areas. Thereafter, when a request for communication with the terminal device 12 occurs during communication with the terminal device 11, the base station device 10 uses a part of the wireless resources 25 in the wireless resource 20 allocated to the terminal device 11. , Transmit data to the terminal device 12. In addition, before the start of data transmission, the base station apparatus 10 notifies the terminal apparatus 12 of scheduling information 26 related to the data transmission using a radio resource of a frequency different from that of the radio resource 20. The notification of the scheduling information 26 is not limited to the area shown in FIG. 2 in the time-frequency domain, and may be performed using radio resources of other areas.

  The base station apparatus 10 can start communication with the terminal apparatus for URLLC (terminal apparatus 12) in a short time by the above-described interrupt processing for communication with the terminal apparatus (terminal apparatus 11) for eMBB. In the present embodiment, interrupt processing for communication with the eMBB terminal device (terminal device 11) is realized by a mechanism called preemption. Preemption replaces the data addressed to the eMBB terminal (first terminal) with the data addressed to the URLLC terminal (second terminal), and transmits the data to the URLLC terminal Equivalent to.

  As described above, preemption can degrade the reception performance of the eMBB terminal device due to thinning (punching) of data transmitted to the eMBB terminal device. Therefore, the base station apparatus 10 may need to notify the eMBB terminal apparatus of control information related to preemption so that the terminal apparatus for eMBB can appropriately perform demodulation processing. However, when preemption is performed using radio resources allocated to a plurality of terminal devices for eMBB (that is, radio resources in a region across a plurality of radio resources corresponding to different terminal devices), each terminal device When the control information is notified to the terminal, the radio resource is wasted for the notification, and the frequency utilization efficiency is lowered.

  Therefore, in the present embodiment, when preemption is performed using radio resources allocated to a plurality of terminal devices for eMBB, control information can be collectively notified to the plurality of terminal devices. Do. Specifically, during communication with a plurality of terminal devices (terminal devices 11 and 12) for eMBB, the base station device 10 uses a part of radio resources allocated to the plurality of terminal devices. In the case of performing preemption, both individual wireless resources that each terminal device can individually demodulate and the plurality of terminal devices commonly perform demodulation for notification of corresponding control information. Use one of the common radio resources available. Furthermore, the base station apparatus 10 notifies control information related to preemption to a plurality of terminal apparatuses using one of the individual radio resources and the common radio resource.

  In this way, not only individual radio resources but also common radio resources can be used to transmit control information related to preemption, thereby collectively notifying control information to a plurality of terminal devices for eMBB. It will be possible to In the following, configuration examples of the base station device 10 and the terminal device 11 for realizing the above-described processing and an example of processing executed by each device will be described.

<Device configuration>
FIG. 3 is a block diagram showing an example of a hardware configuration of a base station apparatus and a terminal apparatus. The base station apparatus 10 and the terminal apparatus 11 have a hardware configuration as shown in FIG. 3 and have, for example, a CPU 31, a ROM 32, a RAM 33, an external storage apparatus 34, and a communication apparatus 35. The terminal devices 12 and 13 can have the same configuration as the terminal device 11.

  In the base station device 10 and the terminal device 11, a program for realizing the functions of the base station device 10 and the terminal device 11 stored in, for example, the ROM 32, the RAM 33, and the external storage device 34 is executed by the CPU 31. The CPU 31 may be replaced by one or more processors such as an ASIC (application specific integrated circuit), an FPGA (field programmable gate array), and a DSP (digital signal processor).

  The base station apparatus 10 (terminal apparatus 11) controls the communication apparatus 35 by, for example, the CPU 31, and performs communication with the terminal apparatus 11 (base station apparatus 10). In addition, in FIG. 2, although the base station apparatus 10 and the terminal device 11 are shown as having one communication apparatus 35, it is not limited to this. For example, the terminal device 11 may have two or more communication devices 35 to communicate with two or more base station devices, and further, another communication device 35 for communication in another system. May be included.

  The base station apparatus 10 and the terminal apparatus 11 may be provided with dedicated hardware for executing each function, or a part of the hardware is executed, and the other part is executed by a computer that operates a program. It is also good. Also, all functions may be performed by a computer and a program.

  FIG. 4 is a block diagram showing an example of a functional configuration of a base station apparatus. Each function of the base station apparatus 10 is, for example, a logical function realized by the hardware of FIG. 3 and can be realized by the CPU 31 executing a program stored in the ROM 32 or the like. In the present embodiment, the base station apparatus 10 includes a wireless communication unit 41, a scheduling unit 42, a data transmission unit 43, and a notification transmission unit 44.

  The wireless communication unit 41 transmits and receives wireless signals to and from terminal devices such as the terminal devices 11 to 13 by communication in accordance with the cellular communication standard. The scheduling unit 42 schedules uplink communication and downlink communication with each terminal apparatus. In the following, only downlink communication will be described. The scheduling may be performed every scheduling period (such as, for example, TTI (Transmission Time Interval) in Long Term Evolution (LTE)). Also, one scheduling may result in the transmission of one or more slots (or subframes) within the corresponding scheduling period.

  The scheduling unit 42 is a radio resource already assigned to one or more terminal devices (terminal devices 11 and 12) for eMBB when transmitting downlink data to the terminal device (terminal device 13) for URLLC. It is possible to schedule data transmission (interrupt processing) using a part of. This data transmission is realized by preemption as described above.

  The data transmission unit 43 transmits data to each terminal apparatus via the wireless communication unit 41 according to the scheduling result by the scheduling unit 42. The notification transmission unit 44 transmits control information related to preemption (control information related to interrupt processing) to the eMBB terminal device that is affected by the interrupt processing via the wireless communication unit 41. At that time, the notification transmission unit 44 uses either an individual radio resource or a common radio resource as a radio resource (control channel) for transmission of control information according to the criteria described in detail below. The individual radio resource is a radio resource which can be demodulated only by an individual terminal device, and the common radio resource is a radio resource which can be commonly demodulated by any of a plurality of terminal devices. As an example of a common radio resource, a radio resource for multicast which can be demodulated only by a plurality of grouped terminals and a radio resource for broadcast which all terminals can demodulate There is.

  FIG. 5 is a block diagram showing an example of the functional configuration of the terminal device. Each function of the terminal device 11 is, for example, a logical function realized by the hardware of FIG. 3 and can be realized by the CPU 31 executing a program stored in the ROM 32 or the like. In the present embodiment, the terminal device 11 includes a wireless communication unit 51, a data receiving unit 52, a data storage unit 53, a notification receiving unit 54, and a demodulation processing unit 55.

  The wireless communication unit 51 transmits and receives a wireless signal to and from a base station device such as the base station device 10 by communication in accordance with the cellular communication standard. The data receiving unit 52 receives scheduling information from the base station via the wireless communication unit 51, and uses the radio resources allocated by the base station according to the received scheduling information from the base station Receive data The data storage unit 53 stores data received by the data reception unit 52. When data is received from the base station apparatus for each scheduling period, data reception section 52 stores the received data in data storage section 53.

  The notification receiving unit 54 receives control information notified from the base station apparatus (notification transmitting unit 44) from the base station apparatus via the wireless communication unit 51 when the above-described interrupt processing (preemption) is performed. . The notification receiving unit 54 monitors a radio resource (control channel) used for notification of control information so that notification of control information can be received when data is received from the base station apparatus. Specifically, the notification receiving unit 54 attempts to receive control information by performing monitoring on both the individual radio resource and the common radio resource described above. When the control information is received by the notification receiving unit 54, the demodulation processing unit 55 demodulates the data stored in the data storage unit 53 every scheduling period according to the control information.

<Processing procedure of base station apparatus>
FIG. 6 is a flowchart showing the procedure of processing executed by the base station apparatus. When a request for data transmission to the URLLC terminal device occurs during communication with the eMBB terminal device, the base station device 10 of the present embodiment executes the process according to the procedure of FIG. Here, a case where a request for data transmission to the terminal device 13 for URLLC occurs during communication with a plurality of terminal devices 11 and 12 (first and second terminal devices) for eMBB will be described as an example.

  7 and 8 show preemption in the case where data is transmitted to the terminal apparatus 13 by preemption using a part of the radio resources (the radio resource 731) already allocated to the terminal apparatuses 11 and 12. FIG. 16 is a diagram showing an example of transmission of control information related to. FIG. 7 shows an example in which control information is transmitted using a common radio resource (radio resource 740), and FIG. 8 transmits control information using individual radio resources (radio resources 741 and 742). An example is shown. The time positions, frequency positions and sizes of the radio resources 740 to 742 used for transmission of control information shown in FIG. 7 and FIG. 8 are merely examples, and can be arbitrarily determined in accordance with the cellular communication standard. Is possible. Moreover, in FIG.7 and FIG.8, although the case where the radio | wireless resource respectively allocated to a several terminal device adjoins in a frequency direction between terminal devices is shown as an example, it is not necessary to adjoin.

  First, in S61, the base station apparatus 10 schedules data transmission to the terminal apparatus 13. In this example, as shown in FIG. 7 (A), the wireless resources in the wireless resources 711 and 721 allocated to the terminal devices 11 and 12, respectively, and the wireless resources in the continuous region extending over the wireless resources 711 and 721. It is assumed that data transmission using the resource 731 is scheduled. That is, in S62, the base station apparatus 10 uses a part of the radio resources 731 in the radio resources 711 and 721 already allocated to the plurality of terminal apparatuses during communication with the plurality of terminal apparatuses 11 and 12. Then, it is determined to perform transmission processing (preemption) for transmitting data addressed to the terminal device 13.

  Next, in S62, the base station apparatus 10 transmits data to the terminal apparatus 13 by preemption according to the scheduling result in S61. Specifically, the base station apparatus 10 thins out the data addressed to the terminal apparatuses 11 and 12 in the wireless resource 731 and replaces the data with data addressed to the terminal apparatus 13 and transmits data addressed to the terminal apparatus 13. Furthermore, in S63, the base station apparatus 10 selects an individual radio resource or a common radio resource as a radio resource for transmission of control information related to the preemption performed in S62.

  In the present embodiment, the base station apparatus 10 aligns the timing at which the scheduled data transmission to the terminal apparatus 11 is completed and the timing at which the scheduled data transmission to the terminal apparatus 12 is completed. Determine if This determination is performed based on the scheduling result (scheduling information 712, 722) of data transmission to the terminal devices 11, 12. As shown in FIG. 7A, the base station apparatus 10 selects a common radio resource when the completion timing of data transmission is aligned between the terminal apparatus 11 and the terminal apparatus 12. On the other hand, as shown in FIG. 8A, when the completion timing of data transmission is not aligned between the terminal device 11 and the terminal device 12, the base station device 10 selects an individual radio resource.

  If control information is transmitted using a common radio resource when the completion timing of data transmission is not aligned, there is a delay in the demodulation processing in the terminal device (the terminal device 12 in FIG. 8A) in which the communication is completed first. It may occur. According to the above-described selection process, when the completion timing of the data transmission is not aligned, the dedicated radio resource is used, so it is possible to prevent such a delay in the demodulation process. Also, when the completion timing of data transmission is aligned, by transmitting control information using a common radio resource, it is possible to collectively transmit control information addressed to a plurality of terminal devices. This makes it possible to prevent waste of radio resources and to improve frequency utilization efficiency.

  Here, with reference to FIG. 7 and FIG. 9, the example of the method of transmitting control information addressed to a several terminal device collectively is demonstrated. The base station apparatus 10 includes, in the control information, information indicating the radio resource 731 for which preemption is performed. As information indicating the wireless resource 731 as shown in FIG. 7A, for example, control is performed on region information indicating the starting point of the region (target region) in which the wireless resource 731 is disposed and the size (in the time direction and frequency direction). Included in the information.

  Specifically, as shown in FIG. 9B, information indicating the start point a of the target area, the size b in the frequency direction, and the size c in the time direction is generated as area information. In the case of FIG. 9B, as shown in FIG. 9A, an area belonging to the wireless resource 711 allocated to the terminal apparatus 11 and an area belonging to the wireless resource 721 allocated to the terminal apparatus 12 in the target area The amount of information can be smaller than when individually generating area information. 9A, the size c of the target area in the time direction, the start point a1 of the area on the wireless resource 711 side, the size b1 in the frequency direction, the start point a2 of the area on the wireless resource 721 side, and the frequency direction Information indicating the size b2 is generated as area information. As shown in FIG. 9B, by including area information with a smaller amount of information in the control information and transmitting the control information to the terminal devices 11 and 12 collectively using the common radio resource, the frequency can be increased. It is possible to improve the utilization efficiency.

  Further, FIG. 7B shows a case where preemption is performed in units of OFDM symbols (that is, the radio resource 731 occupies the area in units of OFDM symbols). In this case, the base station apparatus 10 may include, for example, only information (for example, the number or index of the OFDM symbol) indicating the OFDM symbol corresponding to the wireless resource 731 as the area information in the control information. Also in this case, since the amount of control information can be small, it is possible to improve frequency utilization efficiency by collectively transmitting the control information to the terminal devices 11 and 12 using common radio resources. .

  As shown in FIG. 8B, in the wireless resource 711 assigned to the terminal device 11, a region (wireless resource 731a) used for transmitting data to the terminal device 13 and a wireless assignment assigned to the terminal device 12 There may be a case where the area (wireless resource 731b) used for transmission of data to the terminal device 13 in the resource 721 is not continuous. That is, as in the wireless resource 731a and the wireless resource 731b, preemption may be performed with independent wireless resources between the terminal apparatuses 11 and 12. In such a case, as shown in FIG. 8B, the base station apparatus 10 may select not the common radio resource but the individual radio resources (radio resources 741 and 742) in S63.

  Thereafter, when data transmission to the terminal devices 11 and 12 using the wireless resources 711 and 721 is all completed, the base station apparatus 10 uses the radio resource selected in S63 for control information related to preemption in S64 To the terminal devices 11 and 12.

  Specifically, when the base station apparatus 10 selects the common radio resource, as shown in FIG. 7, the terminal using the radio resource 740 according to the completion of the data transmission to the terminal apparatuses 11 and 12 Control information addressed to the devices 11 and 12 is transmitted. On the other hand, when the base station apparatus 10 selects an individual radio resource, as shown in FIG. 8, control to the terminal apparatus 11 is performed using the radio resource 741 according to the completion of data transmission to the terminal apparatus 11. Send information Furthermore, in response to the completion of data transmission to the terminal device 12, control information addressed to the terminal device 12 is transmitted using the wireless resource 742. Thereafter, the base station device 10 ends the process.

<Processing procedure of terminal device>
FIG. 10 is a flowchart showing the procedure of processing executed by the eMBB terminal device. When the terminal device 11 receives the scheduling information (the scheduling information 712 of FIG. 7) from the base station device 10, the terminal device 11 executes a process according to the procedure of FIG. Here, although the terminal device 11 will be described, the terminal device 12 can also execute the same process when receiving scheduling information (scheduling information 722 in FIG. 7) from the base station device 10.

  First, in S101, the terminal apparatus 11 receives data from the base station apparatus 10 using the radio resource 711 allocated by the base station apparatus 10 according to the received scheduling information 712. Furthermore, in S102, the terminal device 11 stores the received data in the scheduling period corresponding to the scheduling information 712 in the data storage unit 53.

  Thereafter, in S103, the terminal apparatus 11 attempts to receive control information for both the individual radio resource and the common radio resource, which are radio resources (control channels) used for notification of control information, and control information from the base station apparatus 10 Is determined. If the control information has been received, the terminal device 11 advances the process to S104, performs demodulation of the data stored in the data storage unit 53 according to the received control information, and ends the process. In this case, the terminal device 11 can perform demodulation processing by thinning out the data received by the wireless resource indicated by the received control information. On the other hand, when the control information has not been received, the terminal device 11 proceeds with the process to S105, performs normal demodulation process on the data stored in the data storage unit 53, and ends the process.

  As described above, according to the present embodiment, when preemption is performed using radio resources allocated to the plurality of terminal devices 11 and 12, control information for the plurality of terminal devices 11 and 12 is obtained. It becomes possible to notify at once. This makes it possible to prevent waste of radio resources and to improve frequency utilization efficiency.

Second Embodiment
In the second embodiment, an example in which preemption is performed for data transmission to a terminal for URLLC when radio resources are allocated to a terminal for eMBB by multi-user MIMO (MU-MIMO) will be described. Do. In the following, description of parts in common with the first embodiment will be omitted, and different parts will be described.

  FIG. 11 is a diagram illustrating an example of transmission of control information related to preemption according to the present embodiment. In this example, communication with the terminal device 11 and communication with the terminal device 12 are multiplexed (spatial multiplexed) in different spatial layers by MU-MIMO, that is, radio resources of different spatial layers are in the terminal device 11, Assigned to 12. The base station apparatus 10 transmits data addressed to the terminal apparatus 11 using the radio resource 711 of layer 1 and transmits data addressed to the terminal apparatus 12 using the radio resource 721 of layer 2. In the example of FIG. 11, the base station apparatus 10 uses a part of the radio resources (the radio resource 731) already assigned to the terminal apparatuses 11 and 12 while transmitting data to the terminal apparatuses 11 and 12. Then, the data is transmitted to the terminal device 13 by preemption. At this time, the time position and the frequency position of the radio resource 731 in which preemption is performed are the same between layers, and data transmission is performed without performing space multiplexing.

  In the present embodiment, the base station apparatus 10 can select an individual radio resource or a common radio resource as a radio resource for transmission of control information related to preemption, as in the first embodiment (S63). The base station apparatus 10 can select an individual radio resource or a common radio resource based on, for example, whether or not the completion timing of data transmission is aligned between the terminal apparatus 11 and the terminal apparatus 12. As a result, as in the first embodiment, when the completion timing of data transmission is not aligned, it is possible to prevent a delay from being generated in the demodulation process in the terminal device which has completed communication first among the terminal devices 11 and 12 .

  When the common radio resource is selected, the base station apparatus 10 notifies the control information to the terminal apparatuses 11 and 12 by transmission using a radio resource of one space layer and to which transmission diversity is applied. In the example of FIG. 11, the base station apparatus 10 uses a radio resource 740 which is a common radio resource of layer 1. Furthermore, the base station apparatus 10 collectively transmits control information addressed to the terminal apparatuses 11 and 12 by transmission to which the transmission diversity in the radio resource 740 is applied. Thereby, it is possible to improve the reception quality when the terminal devices 11 and 12 receive the control information.

  According to the present embodiment, even when MU-MIMO is applied to a plurality of terminal apparatuses 11 and 12, preemption is performed for a plurality of terminal apparatuses 11 and 12 to which radio resources of different spatial layers are allocated. Related control information can be notified collectively. This makes it possible to prevent waste of radio resources and to improve frequency utilization efficiency.

Third Embodiment
In the third embodiment, when selecting a radio resource for transmission of control information related to preemption, an individual radio resource or a common radio resource is selected based on the operation state of the eMBB terminal device by the intermittent reception (DRX) function. An example of selecting will be described. Descriptions of parts in common with the first embodiment will be omitted, and different parts will be described.

  12 and 13 are diagrams showing an example of transmission of control information related to preemption based on the operation state of the terminal device according to the present embodiment. In the present embodiment, the terminal devices 11 and 12 have a DRX function that operates to receive data in the on state and not to receive data in the off state. Further, the base station apparatus 10 may control switching of the operation state (on state or off state) of the terminal devices 11 and 12. Alternatively, the terminal devices 11 and 12 may autonomously switch the operation state and feed back information indicating the operation state to the base station device 10. In any case, the base station apparatus 10 can grasp the operating state (on state or off state) of the terminal devices 11 and 12.

  In the present embodiment, as shown in FIG. 12, the base station apparatus 10 performs timing t1 at which data transmission scheduled to the terminal apparatus 11 and data transmission scheduled to the terminal apparatus 12 are completed. When both of the terminal devices 11 and 12 are in the on state, the common radio resource (radio resource 740) is selected. In the examples of FIGS. 12 and 13, it is assumed that the completion timing of data transmission to the terminal device 11 and the completion timing of data transmission to the terminal device 12 are not aligned. In this case, by transmitting the control information by the wireless resource 740 immediately after the completion of the data transmission, both of the terminal apparatuses 11 and 12 can receive the control information.

  On the other hand, as shown in FIG. 13, the base station apparatus 10 transmits the scheduled data transmission to the terminal apparatus 11 and the scheduled data transmission to the terminal apparatus 12 at timing t1 when the data transmission is completed. , 12 is in the OFF state, the dedicated radio resources (radio resources 741 and 742) are selected. In the example of FIG. 13, after the completion of the data transmission to the terminal device 12, the terminal device 12 shifts from the on state to the off state until the data transmission to the terminal device 11 is completed. In this case, even if the control information is transmitted at the timing when the data transmission to the terminal device 11 is completed, the terminal device 12 can not receive the control information. In such a case, the base station apparatus 10 transmits control information to each of the terminal apparatuses 11 and 12 using individual radio resources.

  According to the present embodiment, it is possible to collectively notify control information to the terminal devices 11 and 12 according to the operation state of the terminal devices 11 and 12. This makes it possible to prevent waste of radio resources and to improve frequency utilization efficiency.

10: base station apparatus, 11 to 13: terminal apparatus 41: wireless communication unit, 42: scheduling unit, 43: data transmission unit, 44: notification transmission unit 51: wireless communication unit, 52: data reception unit, 53: data storage Unit 54: Notification receiving unit 55: Demodulation processing unit

Claims (14)

Transmission processing for transmitting data addressed to a third terminal apparatus using part of radio resources in radio resources allocated to the first and second terminal apparatuses during communication with the first and second terminal apparatuses Decision means for deciding to
Transmitting means for transmitting data to the third terminal device according to the determination by the determination means using the part of the radio resources;
Any of individual radio resources that can be demodulated by the first and second terminal apparatuses, and common radio resources that can be commonly demodulated by both the first and second terminal apparatuses Notification means for notifying the first and second terminals of control information related to the transmission process using any of the radio resources;
A base station apparatus characterized by having: The transmission means replaces the data addressed to the first terminal apparatus and the data addressed to the second terminal apparatus in the part of the radio resources with the data addressed to the third terminal apparatus, and sends the data to the third terminal apparatus. The base station apparatus according to claim 1, which transmits. The common radio resource is a radio resource in which only a plurality of grouped terminal devices can perform demodulation, or a radio resource in which all the terminal devices can perform demodulation. The base station apparatus of claim 1 or 2. The notification means determines that the timing at which the scheduled data transmission to the first terminal device is completed and the timing at which the scheduled data transmission to the second terminal device is not aligned. The base station apparatus according to any one of claims 1 to 3, wherein the common radio resource is used when the individual radio resources are used and aligned. The first and second terminal apparatuses have an intermittent reception (DRX) function that operates to receive data in the on state and not receive data in the off state,
The notification means is
At the timing when the scheduled data transmission for the first terminal device and the scheduled data transmission for the second terminal device are completed, at least one of the first and second terminal devices is in the off state In the above case, the individual radio resource is used, and the common radio resource is used when both the first and second terminals are in the on state. The base station device according to any one of 1 to 3. The notification means includes an area used to transmit data to the third terminal device in the wireless resource allocated to the first terminal device, and the third terminal device in the wireless resource allocated to the second terminal device The base station apparatus according to any one of claims 1 to 5, wherein the individual radio resource is used if the area used for transmission of data is not continuous. The notification means is
When notification is performed using the common radio resource, the data transmission scheduled to the first terminal apparatus and the data transmission scheduled to the second terminal apparatus are completed, Notifying the first and second terminals of the control information;
When the notification is performed using the individual radio resource, the control information is notified to the first terminal device according to the completion of scheduled data transmission to the first terminal device, and The base station apparatus according to any one of claims 1 to 6, wherein the control information is notified to the second terminal apparatus according to completion of scheduled data transmission to the terminal apparatus. Communication with the first terminal device and communication with the second terminal device are spatially multiplexed in different spatial layers,
In the case of performing notification using the common radio resource, the notification means uses a radio resource of one spatial layer, and transmits the control information to the first and second transmissions by transmission to which transmission diversity is applied. The base station apparatus according to any one of claims 1 to 7, which notifies the second terminal apparatus. When the data transmission to the third terminal apparatus is performed in OFDM symbol units, the notification means includes information indicating the used OFDM symbol in the control information, and is not performed in OFDM symbol units. The base station apparatus according to any one of claims 1 to 8, wherein, in the case, information indicating an area in which a used radio resource is allocated is included in the control information. A terminal device,
Storage means for receiving data from the base station apparatus using a radio resource allocated from the base station apparatus and storing the received data in the storage means;
Related to the transmission process notified from the base station apparatus when the transmission process of data to another terminal apparatus is performed using a part of the radio resources in the radio resource allocated to the terminal apparatus And a common radio resource that can be commonly demodulated by a plurality of terminal apparatuses including the terminal apparatus. Receiving means for attempting to receive the control information for both
Demodulation means for demodulating data stored in the storage means in accordance with the control information received by the receiving means;
A terminal device characterized by having. It is a control method of a base station apparatus, and
Transmission processing for transmitting data addressed to a third terminal apparatus using part of radio resources in radio resources allocated to the first and second terminal apparatuses during communication with the first and second terminal apparatuses A decision process to decide to do
Transmitting, using the part of the radio resources, data to the third terminal according to the determination in the determining step;
Any of individual radio resources that can be demodulated by the first and second terminal apparatuses, and common radio resources that can be commonly demodulated by both the first and second terminal apparatuses A notification step of notifying the first and second terminal devices of control information related to the transmission process using any of the wireless resources;
A control method characterized by comprising: It is a control method of a terminal device, and
An accumulation step of receiving data from the base station apparatus using a radio resource allocated from the base station apparatus and accumulating the received data in a storage unit;
Related to the transmission process notified from the base station apparatus when the transmission process of data to another terminal apparatus is performed using a part of the radio resources in the radio resource allocated to the terminal apparatus And a common radio resource that can be commonly demodulated by a plurality of terminal apparatuses including the terminal apparatus. Attempting to receive the control information for both
A demodulation step of demodulating the data stored in the storage unit according to the control information received in the reception step;
A control method characterized by comprising:   The program for making the computer with which a base station apparatus is equipped perform each process of the control method of Claim 11.   The program for making the computer with which a terminal device is equipped perform each process of the control method of Claim 12.

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