Control device and method
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Filing Date
- 2024-07-31
- Publication Date
- 2026-05-11
Abstract
Description
Control device and method
[0001] The present disclosure relates to a control device and method.
[0002] The Technical Specification of the 3rd Generation Partnership Project (3GPP (registered trademark)) proposes a User Equipment (UE) power saving technique (for example, Non-Patent Document 1). The UE power saving technique includes discontinuous reception (DRX).
[0003] Chapter 11 of Non-Patent Document 1 describes that the UE's Physical Downlink Control Channel (PDCCH) monitoring activity in RRC_CONNECTED mode is governed by DRX. When DRX is configured, the UE does not need to continuously monitor the PDCCH. DRX is characterized by an on-duration, an inactivity timer, a retransmission timer, a DRX cycle, and an active time. The on-duration is the duration a UE waits to receive PDCCHs after waking up. If the UE successfully decodes a PDCCH, the UE stays awake and starts the inactivity timer. The inactivity timer is the duration a UE waits to successfully decode the (next) PDCCH since the previous successful PDCCH decode. If the UE fails to decode the PDCCH before the inactivity timer expires, the UE can return to sleep. The retransmission timer is the duration for which the UE must be awake to receive retransmissions. The DRX cycle specifies the periodic repetition of the on duration followed by a possible period of inactivity. The UE is in the "active state" during the active time and in the "inactive state" outside of the active time. The active time is the total time that the UE monitors the PDCCH. The active time includes the on duration within the DRX cycle, the time the UE performs continuous reception while the inactivity timer has not expired, and the time the UE performs continuous reception while waiting for a retransmission opportunity.
[0004] Furthermore, Dual Connectivity is proposed in the 3GPP Technical Specification (for example, Chapter 4 of Non-Patent Document 2). With Dual Connectivity, a UE can connect to two base stations and transmit and receive packets to and from these two base stations using multiple component carriers supported by these two base stations.
[0005] 3GPP TS 38.300 V17.5.0 (2023-06) "3rd Generation Partnership Project; Technical Specification Group Radio Access Network; NR; NR and NG-RAN Overall Description; Stage 2 (Release 17)", June 20233GPP TS 37.340 V17.5.0 (2023-06) "3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA) and NR; Multi-connectivity; Stage 2 (Release 17) ", June 20233GPP TS 38.425 V17.3.0 (2023-04) "3rd Generation Partnership Project; Technical Specification Group Radio Access Network; NG-RAN; NR user plane protocol (Release 17) ", April 2023
[0006] The present inventors have found that when UE discontinuous reception and dual connectivity are applied between a UE and a first communication device and a second communication device, packets destined for the UE may not be transmitted efficiently. That is, for example, when the first communication device is used without using the second communication device to transmit packets destined for the UE, the "UE state with DRX applied (hereinafter, sometimes simply referred to as the "UE state")" managed by the first communication device is an Active state, and the UE state managed by the second communication device is an Inactive state. In this state, even if an attempt is made to use the second communication device in addition to the first communication device to transmit packets destined for the UE, it is currently necessary to wait for the UE state managed by the second communication device to become an Active state due to the arrival of an On duration.
[0007] An object of the present disclosure is to provide a control device and method that can realize efficient transmission to a UE when discontinuous reception of the UE and dual connectivity are applied between the UE and a first communication device and a second communication device. It should be noted that this object is only one of multiple objects that multiple embodiments disclosed in this specification aim to achieve. Other objects or objectives and novel features will become apparent from the description of this specification or the accompanying drawings.
[0008] In one aspect, the control device includes: control means for executing control to transmit to the second communication device a control signal for maintaining the UE state managed by the second communication device in the Active state or for changing it from the Inactive state to the Active state, when Dual connectivity, in which multiple packets destined for a user equipment (UE) can be distributed to both a first communication device and a second communication device and transmitted to the UE via the first communication device and the second communication device, is applied to the first communication device and the second communication device, and discontinuous reception (DRX) is applied to communication between the UE and the first communication device and communication between the UE and the second communication device, so that the UE state for the first communication device is in the Active state and the UE state for the second communication device is about to change from the Active state to the Inactive state.
[0009] In another aspect, a method executed by a control device includes: when Dual connectivity, in which a plurality of packets destined for a user equipment (UE) can be distributed to both a first communication device and a second communication device and transmitted to the UE via the first communication device and the second communication device, is applied to the first communication device and the second communication device, and discontinuous reception (DRX) is applied to communication between the UE and the first communication device and communication between the UE and the second communication device, such that a UE state for the first communication device is an Active state and a UE state for the second communication device is about to change from an Active state to an Inactive state, executing control to transmit to the second communication device a control signal for maintaining a UE state managed by the second communication device in an Active state or for changing from an Inactive state to an Active state.
[0010] The present disclosure provides a control device and method that can achieve efficient transmission to a UE when discontinuous reception of the UE and dual connectivity are applied between the UE and a first communication device and a second communication device.
[0011] Fig. 1 is a block diagram showing an example of a system of the present disclosure; Fig. 2 is a diagram showing an example of a DRX cycle; Fig. 3 is a block diagram showing an example of a control device of the present disclosure; Fig. 4 is a block diagram showing another example of a control device of the present disclosure; Fig. 5 is a diagram showing an example of the configuration of a control device; Fig. 6 is a diagram showing an example of the configuration of a higher-level device; Fig. 7 is a diagram showing an example of the configuration of a communication device; Fig. 8 is a block diagram showing an example of the configuration of a UE.
[0012] Hereinafter, embodiments will be described with reference to the drawings. In this disclosure, the drawings may relate to one or more embodiments. Furthermore, each element in the drawings may apply to one or more embodiments. Furthermore, in the embodiments, the same or equivalent elements are given the same reference numerals, and redundant description will be omitted.
[0013] The multiple embodiments described below can be implemented independently or in appropriate combination. These multiple embodiments have different novel features. Therefore, these multiple embodiments contribute to solving different purposes or problems and to achieving different effects.
[0014] As used herein, depending on the context, "if" may be interpreted to mean "when," "at or around the time," "after," "upon," "in response to determining," "in accordance with a determination," or "in response to detecting." These expressions may be interpreted to have the same meaning, depending on the context.
[0015] <System Configuration Example> First, an example of a system configuration common to multiple embodiments will be described. Fig. 1 is a block diagram showing an example of a system according to the present disclosure. In Fig. 1, the system 1 includes communication devices 10 and 20, a higher-level device 30, and a user equipment (UE) 40.
[0016] In the system 1, a plurality of packets addressed to the UE 40 can be distributed to the communication apparatus 10 and the communication apparatus 20 by the higher-level apparatus 30 and transmitted to the UE 40 via the communication apparatus 10 and the communication apparatus 20. That is, Dual Connectivity is applied between the communication apparatus 10 and the communication apparatus 20 and the UE 40. This allows the UE 40 to receive packets via the communication apparatus 10 and the communication apparatus 20 using a plurality of component carriers supported by the communication apparatus 10 and the communication apparatus 20.
[0017] In addition, discontinuous reception (DRX) is applied to the communication between the UE 40 and the communication device 10 and the communication between the UE 40 and the communication device 20. The Physical Downlink Control Channel (PDCCH) monitoring activity of the UE 40 in the RRC_CONNECTED mode is governed by DRX. When DRX is configured, the UE does not need to continuously monitor the PDCCH. DRX is characterized by an on-duration, an inactivity timer, a retransmission timer, a DRX cycle, and an active time. The on-duration is the duration that the UE waits to receive PDCCHs after waking up. If the UE 40 successfully decodes the PDCCH, the UE 40 stays awake and starts the inactivity timer. The inactivity timer is the duration that the UE 40 waits to successfully decode the (next) PDCCH since the last successful PDCCH decode. If the PDCCH fails to be decoded before the inactivity timer expires, the UE can return to sleep. The retransmission timer is the duration that the UE must stay awake to receive retransmissions. The DRX cycle specifies the periodic repetition of the on duration followed by a possible period of inactivity. The active time is the total time that the UE 40 monitors the PDCCH. The active time includes the on duration within the DRX cycle, the time the UE performs continuous reception while the inactivity timer has not expired, and the time the UE performs continuous reception while waiting for a retransmission opportunity.
[0018] Figure 2 shows an example of a DRX cycle. As shown in Figure 2, one DRX cycle includes an on-duration at the beginning of the cycle. This on-duration is one of the DRX active periods of the UE 40. After the on-duration, there is a DRX opportunity. During this DRX opportunity, the UE 40 can enter sleep mode if neither the inactivity timer nor the retransmission timer is running.
[0019] The host device 30 allocates resources for each of the communication between the UE 40 and the communication device 10 and the communication between the UE 40 and the communication device 20. Then, the host device 30 transmits information regarding the resources allocated to the communication between the UE 40 and the communication device 10 to the UE 40 via the communication device 10. At this time, the communication device 10 transmits information regarding the resources allocated to the communication between the UE 40 and the communication device 10 to the UE 40 using a PDCCH. Also, the host device 30 transmits information regarding the resources allocated to the communication between the UE 40 and the communication device 20 to the UE 40 via the communication device 20. At this time, the communication device 20 transmits information regarding the resources allocated to the communication between the UE 40 and the communication device 20 to the UE 40 using a PDCCH.
[0020] The UE 40 manages the state of the UE 40 (UE state) for the communication device 10 using the various timers described above. The UE state for the communication device 10 managed by the UE 40 may be referred to hereinafter as the "UE state for the communication device 10 in the UE 40." For example, during the on duration, the UE state for the communication device 10 in the UE 40 becomes the Active state. Then, for example, when the UE state for the communication device 10 in the UE 40 is the Active state, an Inactivity Timer starts when the UE 40 receives a PDCCH from the communication device 10. Then, the UE state for the communication device 10 in the UE 40 remains the Active state until the Inactivity Timer expires.
[0021] Furthermore, the UE 40 manages the state of the UE 40 (UE state) for the communication device 20 using the various timers described above. The UE state for the communication device 20 managed by the UE 40 may be referred to hereinafter as the "UE state for the communication device 20 in the UE 40." For example, during the on duration, the UE state for the communication device 20 in the UE 40 becomes the Active state. Then, for example, when the UE state for the communication device 20 in the UE 40 is the Active state, an Inactivity Timer starts when the UE 40 receives a PDCCH from the communication device 20. Then, the UE state for the communication device 20 in the UE 40 remains the Active state until the Inactivity Timer expires.
[0022] Here, the communication device 10 manages the UE state of the UE 40 by sharing the start trigger and end trigger of each timer with the UE 40. Hereinafter, the UE state managed by the communication device 10 may be referred to as the "UE state in the communication device 10."
[0023] Furthermore, communication device 20 manages the UE state of UE 40 by sharing start triggers and end triggers of each timer with UE 40. Hereinafter, the UE state managed by communication device 20 may be referred to as the "UE state in communication device 20."
[0024] The communication device 10, the communication device 20, and the higher-level device 30 may each be a Radio Access Network (RAN) node. The higher-level device 30 may be, for example, a Central Unit (CU). The CU may include a Control Plane (CP) Unit and one or more User Plane (UP) Units. Furthermore, the communication device 10 and the communication device 20 may each be a Distributed Unit (DU) or a Radio Unit (RU). The CU may be a logical node that hosts Radio Resource Control (RRC), Service Data Adaptation Protocol (SDAP), and Packet Data Convergence Protocol (PDCP) protocols. The DU may be a logical node that hosts Radio Link Control (RLC), Medium Access Control (MAC), and Physical (PHY) layers.
[0025] The communication device 10 and the higher-level device 30 may constitute one base station (e.g., a gNB or an en-gNB), and the communication device 20 may be included in another base station (e.g., a gNB or an en-gNB). Alternatively, the communication device 20 and the higher-level device 30 may constitute one base station, and the communication device 10 may be included in another base station. In the following, the description will be given on the assumption that the communication device 10 and the higher-level device 30 constitute one base station, and the communication device 20 is included in another base station.
[0026] First Embodiment Fig. 3 is a block diagram showing an example of a control device according to the present disclosure. In Fig. 3, a control device 50 includes a control unit 51.
[0027] The control device 50 may be provided in the UE 40. In other words, the UE 40 may include the control unit 51.
[0028] The control unit 51 manages the above-mentioned "UE state of the UE 40 with respect to the communication device 10" and "UE state of the UE 40 with respect to the communication device 20."
[0029] When the UE state of the UE 40 for the communication device 10 is an Active state and the UE state of the UE 40 for the communication device 20 is about to change from the Active state to an Inactive state or has already changed from the Active state to an Inactive state, the control unit 51 executes control to transmit a "control signal" to the communication device 20. This "control signal" is a control signal for causing the above-mentioned "UE state in the communication device 20" to remain in the Active state or to change from the Inactive state to the Active state. The control unit 51 executes "transmission control" to cause the UE 40 to transmit the above-mentioned control signal to the communication device 20. At this time, the above-mentioned control signal is transmitted from a communication unit (not shown) of the UE 40 to the communication device 20.
[0030] For example, if the amount of data for data packets transmitted to UE 40 is greater than a predetermined level, it is advantageous for the data packets addressed to UE 40 to be transmitted to UE 40 using communication device 10 and communication device 20. On the other hand, if the amount of data for data packets transmitted to UE 40 is less than a predetermined level, communication device 20 may not be used, and the data packets addressed to UE 40 may be transmitted to UE 40 via communication device 10. In this case, there is a high possibility that the UE state of communication device 20 will change from an Active state to an Inactive state. However, if the amount of data for data packets transmitted to UE 40 exceeds a predetermined level when the UE state of communication device 20 is in an Inactive state, there is a possibility that communication device 20 cannot be used immediately even if an attempt is made to use it. Therefore, for example, the control unit 51 may execute transmission control to cause UE 40 to transmit the above-mentioned control signal, triggered by the amount of data for data packets transmitted to UE 40 via communication device 10 exceeding a predetermined threshold. As a result, if it is expected that the amount of data for data packets transmitted to UE 40 will exceed a predetermined level, the control unit 51 can maintain the UE state of communication device 20 in an Active state. As a result, the control device 50 can realize efficient transmission to the UE 40 when discontinuous reception of the UE 40 and dual connectivity are applied between the UE 40 and the communication device 10 and the communication device 20 .
[0031] The above phrase "when the UE state for the communication device 20 in the UE 40 is likely to change from an Active state to an Inactive state" can also be rephrased as "when the UE state for the communication device 20 in the UE 40 is a predetermined time before the timing at which the UE state for the communication device 20 in the UE 40 is likely to change from an Active state to an Inactive state." Furthermore, "a predetermined time before the timing at which the UE state for the communication device 20 in the UE 40 is likely to change from an Active state to an Inactive state" can also be rephrased as "a predetermined time before the end timing of the Active time for the communication device 20 in the UE 40." The "predetermined time before the end timing of the Active time" is, for example, a predetermined time before the end timing of the on-duration or a predetermined time before the end timing of the Inactivity Timer. Note that the value of the "predetermined time" may be stored in advance in the control device 50 (UE 40). Alternatively, the value of the "predetermined time" may be instructed to the control device 50 (UE 40) by the higher-level device 30. In this case, the higher-level device 30 may, for example, transmit an RRC message including the value of the "predetermined time" as part of the configuration information described below to the control device 50 (UE 40).
[0032] The control signal is, for example, a signal for starting or restarting an inactivity timer for the UE 40 in the communication device 20. The control signal may be, for example, a scheduling request or a Random Access Channel (RACH) signal. Alternatively, the control signal may be a predetermined packet. The packet may be a new (i.e., dedicated) packet or a known packet.
[0033] If the control signal is a scheduling request, the control unit 51 may cause the UE 40 to transmit the scheduling request at the last opportunity for the UE 40 to transmit a scheduling request during the active time for the communication device 20 .
[0034] If the control signal is a scheduling request, the control unit 51 may cause the UE 40 to transmit the RACH signal at the last opportunity to transmit the RACH signal during the Active time for the communication device 20 in the UE 40 .
[0035] The control unit 51 may receive configuration information related to the "transmission control" by the control unit 51 described above from the communication device 10 or the communication device 20. The control unit 51 may receive the above configuration information via RRC (Radio Resource Control). That is, the communication device 10 or the communication device 20 may transmit an RRC message including the above configuration information to the control device 50 (UE 40).
[0036] As described above, in the control device 50, when the UE state of the UE 40 for the communication device 10 is an Active state and the UE state of the UE 40 for the communication device 20 is about to change from the Active state to an Inactive state or has already changed, the control unit 51 executes control to transmit a control signal to the communication device 20. This control signal is a control signal for keeping the UE state of the communication device 20 in the Active state or for changing it from the Inactive state to the Active state.
[0037] With this configuration of the control device 50, the control device 50 can realize efficient transmission to the UE 40 when discontinuous reception of the UE 40 and dual connectivity are applied between the UE 40 and the communication device 10 and the communication device 20. That is, when the UE state of the communication device 20 is in the inactive state, the amount of data for data packets transmitted to the UE 40 may exceed a predetermined level, making it impossible to immediately use the communication device 20 even if an attempt is made to use the communication device 20. In response to this, when the UE state of the communication device 10 in the UE 40 is the active state, the control unit 51 can keep the UE state of the communication device 20 in the active state. As a result, when the amount of data for data packets transmitted to the UE 40 exceeds a predetermined level, the communication device 20 can immediately be used in addition to the communication device 10 for transmitting data packets to the UE 40. This allows the control device 50 to realize efficient transmission to the UE 40 when discontinuous reception of the UE 40 and dual connectivity are applied between the UE 40 and the communication device 10 and the communication device 20.
[0038] Second Embodiment Fig. 4 is a block diagram showing another example of a control device according to the present disclosure. In Fig. 4, a control device 60 includes a control unit 61.
[0039] The control device 60 may be provided in a node that hosts the PDCP layer. That is, the control device 60 may be provided in the communication device 10 or the higher-level device 30. In other words, the communication device 10 or the higher-level device 30 may include a control unit 61.
[0040] Specifically, for example, when the communication device 10 is a first DU and the communication device 20 is a second DU, the control device 60 may be provided in the first DU (i.e., the communication device 10). Alternatively, for example, when the communication device 10 is a first DU and the communication device 20 is a second DU, the control device 60 may be provided in a CU-UP of a CU (i.e., the higher-level device 30) that hosts the second DU. Alternatively, for example, when the communication device 10 is a first base station (e.g., a gNB or an en-gNB) and the communication device 20 is a second base station (e.g., a gNB or an en-gNB), the control device 60 may be provided in the first base station (i.e., the communication device 10).
[0041] When the UE state of the UE 40 for the communication device 10 is an Active state and the UE state of the UE 40 for the communication device 20 is about to change from the Active state to an Inactive state or has already changed from the Active state to an Inactive state, the control unit 61 executes control to transmit a "control signal" to the communication device 20. This "control signal" is a control signal for causing the above-mentioned "UE state in the communication device 20" to remain in the Active state or to change from the Inactive state to the Active state. The control unit 61 executes "transmission control" to cause the above-mentioned control signal to be transmitted to the higher-level device 30 for the communication device 20.
[0042] The control signal may be a notification signal including information indicating the presence of data addressed to UE 40. This notification signal may be, for example, a user data frame including a flag indicating the presence of data addressed to UE 40 but not including data addressed to UE 40. Here, the user data frame is typically used by the higher-level device 30 to transmit data addressed to UE 40 to the communication device 10 (communication device 20). Here, a user data frame including a flag indicating the presence of data addressed to UE 40 but not including data addressed to UE 40 is used as the notification signal.
[0043] The notification signal may be transmitted using the X2 interface or the Xn interface, or may be transmitted using the C-plane.
[0044] As described above, in the control device 60, when the UE state of the UE 40 for the communication device 10 is an Active state and the UE state of the UE 40 for the communication device 20 is about to change from the Active state to an Inactive state or has already changed, the control unit 61 executes control to transmit a control signal to the communication device 20. This control signal is a control signal for keeping the UE state of the communication device 20 in the Active state or for changing it from the Inactive state to the Active state.
[0045] With this configuration of the control device 60, the control device 60 can realize efficient transmission to the UE 40 when discontinuous reception of the UE 40 and dual connectivity are applied between the UE 40 and the communication device 10 and the communication device 20. That is, when the UE state of the communication device 20 is in the inactive state, the amount of data for data packets transmitted to the UE 40 may exceed a predetermined level, making it impossible to immediately use the communication device 20 even if an attempt is made to use the communication device 20. In response to this, when the UE state of the communication device 10 in the UE 40 is the active state, the control unit 61 can keep the UE state of the communication device 20 in the active state. As a result, when the amount of data for data packets transmitted to the UE 40 exceeds a predetermined level, the control device 60 can immediately use the communication device 20 in addition to the communication device 10 for transmitting data packets to the UE 40. This allows the control device 60 to realize efficient transmission to the UE 40 when discontinuous reception of the UE 40 and dual connectivity are applied between the UE 40 and the communication device 10 and the communication device 20.
[0046] <Other Embodiments> <1> FIG. 5 is a diagram illustrating an example configuration of a control device. In FIG. 5, the control device 100 includes a processor 101 and a memory 102. The control devices 50 and 60 may have the configuration illustrated in FIG. 5. The processor 101 may be, for example, a microprocessor, a microprocessing unit (MPU), or a central processing unit (CPU). The processor 101 may include multiple processors. The memory 102 is configured by a combination of volatile memory and nonvolatile memory. The memory 102 may include multiple physically independent memory devices. The volatile memory may be, for example, static random access memory (SRAM), dynamic RAM (DRAM), or a combination thereof. The nonvolatile memory may be, for example, mask read only memory (MROM), electrically erasable programmable ROM (EEPROM), flash memory, a hard disk drive, or any combination thereof. The memory 102 may include storage located remotely from the processor 101. In this case, the processor 101 may access the memory 102 via an I (Input) / O (Output) interface (not shown).
[0047] The memory 102 may store one or more software modules (computer programs) including instructions and data for performing processing by the control devices 50 and 60. In some implementations, the processor 101 may be configured to read and execute the software modules from the memory 102 to perform processing by the control devices 50 and 60.
[0048] <2> Fig. 6 is a diagram showing an example of the configuration of a higher-level device. In Fig. 6, a device 200 includes a network interface 201, a processor 202, and a memory 203. The higher-level device 30 may have the configuration shown in Fig. 6.
[0049] The network interface 201 is used to communicate with, for example, network elements (eg, the communication devices 10 and 20). The network interface 201 may include, for example, a network interface card (NIC) that complies with the IEEE 802.3 series.
[0050] The processor 202 may be, for example, a microprocessor, an MPU, or a CPU. The processor 202 may include multiple processors.
[0051] The memory 203 is composed of volatile memory and nonvolatile memory. The memory 203 may include multiple physically independent memory devices. The volatile memory is, for example, Static Random Access Memory (SRAM), Dynamic RAM (DRAM), or a combination thereof. The nonvolatile memory is, for example, Mask Read Only Memory (MROM), Electrically Erasable Programmable ROM (EEPROM), flash memory, or a hard disk drive, or any combination thereof. The memory 203 may include storage located remotely from the processor 202. In this case, the processor 202 may access the memory 203 via the network interface 201 or an I / O interface.
[0052] The memory 203 may store one or more software modules (computer programs) including instructions and data for performing processing by the above-described higher-level device 30. In some implementations, the processor 202 may be configured to read and execute the software modules from the memory 203, thereby performing the processing of the above-described higher-level device 30.
[0053] <3> Figure 7 is a diagram showing an example configuration of a communication device. In Figure 7, the device 300 includes an antenna array 301, a radio frequency (RF) transceiver 302, a network interface 303, a processor 304, and a memory 305. When the communication devices 10 and 20 are RUs, the communication devices 10 and 20 may each have the configuration shown in Figure 7. The RF transceiver 302 performs analog RF signal processing for communication with UEs. The RF transceiver 302 may include multiple transceivers. The RF transceiver 302 is coupled to the antenna array 301 and the processor 304. The RF transceiver 302 receives modulation symbol data from the processor 304, generates a transmit RF signal, and provides the transmit RF signal to the antenna array 301. The RF transceiver 302 also generates a baseband receive signal based on the receive RF signal received by the antenna array 301 and provides the baseband receive signal to the processor 304. The RF transceiver 302 may include an analog beamformer circuit for beamforming. The analog beamformer circuitry includes, for example, multiple phase shifters and multiple power amplifiers.
[0054] The network interface 303 is used to communicate with network nodes (eg, the communication devices 10 and 20, and the higher-level device 30). The network interface 303 may include, for example, a network interface card (NIC) that complies with the IEEE 802.3 series.
[0055] The processor 304 performs digital baseband signal processing (data plane processing) and control plane processing for wireless communication. The processor 304 may include multiple processors. For example, the processor 304 may include a modem processor (e.g., a Digital Signal Processor (DSP)) that performs digital baseband signal processing and a protocol stack processor (e.g., a Central Processing Unit (CPU) or a Micro Processing Unit (MPU)) that performs control plane processing.
[0056] The processor 304 may include a digital beamformer module for beamforming, which may include a Multiple Input Multiple Output (MIMO) encoder and precoder.
[0057] The memory 305 is configured by a combination of volatile memory and non-volatile memory. The volatile memory is, for example, Static Random Access Memory (SRAM), Dynamic RAM (DRAM), or a combination thereof. The non-volatile memory is, for example, Mask Read Only Memory (MROM), Electrically Erasable Programmable ROM (EEPROM), flash memory, or a hard disk drive, or any combination thereof. The memory 305 may include storage located remotely from the processor 304. In this case, the processor 304 may access the memory 305 via the network interface 303 or an I / O interface (not shown).
[0058] The memory 305 may store one or more software modules (computer programs) including instructions and data for performing processing by the communication devices 10 and 20. In some implementations, the processor 304 may be configured to read and execute the software modules from the memory 305 to perform processing by the communication devices 10 and 20.
[0059] The antenna array 301 may correspond to the tx-array and rx-array described above.
[0060] If the communication devices 10 and 20 are CUs, the communication devices 10 and 20 may not include the RF transceiver 302 (and the antenna array 301).
[0061] <4> Figure 8 is a block diagram showing an example configuration of a UE. A radio frequency (RF) transceiver 401 performs analog RF signal processing for communication with the communication devices 10 and 20. The RF transceiver 401 may include multiple transceivers. The analog RF signal processing performed by the RF transceiver 401 includes frequency up-conversion, frequency down-conversion, and amplification. The RF transceiver 401 is coupled to an antenna array 402 and a baseband processor 403. The RF transceiver 401 receives modulation symbol data (or OFDM symbol data) from the baseband processor 403, generates a transmit RF signal, and provides the transmit RF signal to the antenna array 402. The RF transceiver 401 also generates a baseband receive signal based on the receive RF signal received by the antenna array 402 and provides it to the baseband processor 403. The RF transceiver 401 may include an analog beamformer circuit for beamforming. The analog beamformer circuit includes, for example, multiple phase shifters and multiple power amplifiers.
[0062] The baseband processor 403 performs digital baseband signal processing (data plane processing) and control plane processing for wireless communications. Digital baseband signal processing includes (a) data compression / decompression, (b) data segmentation / concatenation, (c) transmission format (transmission frame) generation / decomposition, (d) transmission path coding / decoding, (e) modulation (symbol mapping) / demodulation, and (f) generation of OFDM symbol data (baseband OFDM signal) using Inverse Fast Fourier Transform (IFFT). Meanwhile, control plane processing includes communication management for Layer 1 (e.g., transmit power control), Layer 2 (e.g., radio resource management and hybrid automatic repeat request (HARQ) processing), and Layer 3 (e.g., signaling related to attachment, mobility, and call management).
[0063] For example, the digital baseband signal processing by the baseband processor 403 may include signal processing of a Service Data Adaptation Protocol (SDAP) layer, a Packet Data Convergence Protocol (PDCP) layer, a Radio Link Control (RLC) layer, a Medium Access Control (MAC) layer, and a Physical (PHY) layer. Also, the control plane processing by the baseband processor 403 may include processing of a Non-Access Stratum (NAS) protocol, a Radio Resource Control (RRC) protocol, MAC Control Elements (CEs), and Downlink Control Information (DCIs).
[0064] The baseband processor 403 may perform Multiple Input Multiple Output (MIMO) encoding and precoding for beamforming.
[0065] The baseband processor 403 may include a modem processor (e.g., a Digital Signal Processor (DSP)) that performs digital baseband signal processing and a protocol stack processor (e.g., a Central Processing Unit (CPU) or a Micro Processing Unit (MPU)) that performs control plane processing. In this case, the protocol stack processor that performs control plane processing may be shared with the application processor 404, which will be described later.
[0066] The application processor 404 is also referred to as a CPU, MPU, microprocessor, or processor core. The application processor 404 may include multiple processors (multiple processor cores). The application processor 404 executes a system software program (operating system (OS)) and various application programs (e.g., a calling application, a web browser, a mailer, a camera operation application, and a music playback application) read from the memory 406 or other memories, thereby realizing various functions of the UE 40.
[0067] In some implementations, the baseband processor 403 and the application processor 404 may be integrated on a single chip, as indicated by the dashed line (405) in Figure 8. In other words, the baseband processor 403 and the application processor 404 may be implemented as a single System on Chip (SoC) device 405. An SoC device is sometimes called a system Large Scale Integration (LSI) or chipset.
[0068] The memory 406 is volatile memory, nonvolatile memory, or a combination thereof. The memory 406 may include multiple physically independent memory devices. The volatile memory may be, for example, static random access memory (SRAM), dynamic RAM (DRAM), or a combination thereof. The nonvolatile memory may be mask read only memory (MROM), electrically erasable programmable ROM (EEPROM), flash memory, a hard disk drive, or any combination thereof. For example, the memory 406 may include an external memory device accessible from the baseband processor 403, the application processor 404, and the SoC 405. The memory 406 may also include an internal memory device integrated within the baseband processor 403, the application processor 404, or the SoC 405. Furthermore, the memory 406 may include memory within a Universal Integrated Circuit Card (UICC).
[0069] The memory 406 may store one or more software modules (computer programs) including instructions and data for performing the above-described processing by the UE 40. In some implementations, the baseband processor 403 or the application processor 404 may be configured to read and execute the software modules from the memory 406 to perform the above-described processing by the UE 40.
[0070] In addition, the control plane processing and operations performed by the above-mentioned UE 40 can be realized by elements other than the RF transceiver 401 and the antenna array 402, i.e., at least one of the baseband processor 403 and the application processor 404, and the memory 406 storing software modules.
[0071] As described with reference to FIGS. 5-8 , each of the processors included in the communication devices 10 and 20, the UE 40, and the control devices 50 and 60 can execute one or more programs including instructions for causing a computer to perform the algorithms described with reference to the drawings. The programs include instructions (or software code) that, when loaded into a computer, cause the computer to perform one or more functions described in the embodiments. The programs may be stored on a non-transitory computer-readable medium or a tangible storage medium. By way of example and not limitation, computer-readable media or tangible storage media include random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drive (SSD) or other memory technology, CD-ROM, digital versatile disk (DVD), Blu-ray (registered trademark) disc or other optical disk storage, magnetic cassette, magnetic tape, magnetic disk storage, or other magnetic storage device. The programs may also be transmitted on a transitory computer-readable medium or communication medium. By way of example and not limitation, transitory computer-readable media or communication media include electrical, optical, acoustic, or other forms of propagated signals.
[0072] Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above. Various modifications that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the invention. Furthermore, each embodiment can be combined with other embodiments as appropriate.
[0073] Some or all of the above embodiments may be described as, but are not limited to, the following supplementary notes. (Supplementary Note 1) A control device comprising: control means for executing control to transmit to the second communication device a control signal for causing a UE state managed by the second communication device to remain in the Active state or to change from the Inactive state to the Active state, when Dual connectivity, in which multiple packets destined for a user equipment (UE) can be distributed to both a first communication device and a second communication device and transmitted to the UE via the first communication device and the second communication device, is applied to the first communication device and the second communication device, and discontinuous reception (DRX) is applied to communication between the UE and the first communication device and communication between the UE and the second communication device, so that the UE state for the first communication device is in the Active state and the UE state for the second communication device is about to change from the Active state to the Inactive state. (Supplementary Note 2) The control device according to Supplementary Note 1, wherein the control means executes transmission control to cause the control signal to be transmitted to the UE when a data amount of packets transmitted to the UE via the first communication device exceeds a threshold. (Supplementary Note 3) The control device according to Supplementary Note 1, wherein the control means executes transmission control to cause the UE to transmit the control signal before a UE state for the second communication device managed by the UE changes from an active state to an inactive state. (Supplementary Note 4) The control device according to Supplementary Note 3, wherein the control signal is a signal for starting or restarting a DRX Inactivity Timer for the UE in the second communication device. (Supplementary Note 5) The control device according to Supplementary Note 4, wherein the control signal is a scheduling request. (Supplementary Note 6) The control device according to Supplementary Note 5, wherein the control means causes the UE to transmit the scheduling request at the last transmission opportunity for a scheduling request during an active time in which the UE state for the second communication device managed by the UE is an active state. (Supplementary Note 7) The control device according to Supplementary Note 4, wherein the control signal is a Random Access Channel (RACH) signal.(Supplementary Note 8) The control device according to Supplementary Note 7, wherein the control means causes the UE to transmit the RACH signal at the last opportunity to transmit the RACH signal during an active time when the UE state for the second communication device managed by the UE is an active state. (Supplementary Note 9) The control device according to any one of Supplements 2 to 8, wherein the control means receives configuration information related to the transmission control from the first communication device or the second communication device. (Supplementary Note 10) The control device according to Supplementary Note 9, wherein the control means receives the configuration information via Radio Resource Control (RRC). (Supplementary Note 11) The control device according to Supplementary Note 1, wherein the control means executes transmission control to cause a host device of the first communication device to transmit, as the control signal, a notification signal including information indicating the presence of data addressed to the UE. (Supplementary Note 12) The control device according to Supplementary Note 11, wherein the notification signal is a user data frame including a flag indicating the presence of data addressed to the UE and not including data addressed to the UE. (Supplementary Note 13) A UE comprising the control device according to any one of Supplements 2 to 8. (Supplementary Note 14) A higher-level device comprising the control device according to Supplementary Note 11 or 12. (Supplementary Note 15) A method executed by a control device, the method comprising: when Dual connectivity, in which a plurality of packets destined for a user equipment (UE) can be distributed to both a first communication device and a second communication device and transmitted to the UE via the first communication device and the second communication device, is applied to the first communication device and the second communication device, and discontinuous reception (DRX) is applied to communication between the UE and the first communication device and communication between the UE and the second communication device, so that the UE state for the first communication device is an Active state and the UE state for the second communication device is about to change from an Active state to an Inactive state, executing control to transmit to the second communication device a control signal for maintaining the UE state managed by the second communication device as an Active state or for changing it from an Inactive state to an Active state.(Supplementary Note 16) The method according to Supplementary Note 15, wherein executing control to transmit the control signal to the second communication device includes executing transmission control to cause the UE to transmit the control signal, triggered by a data amount of packets transmitted to the UE via the first communication device exceeding a threshold. (Supplementary Note 17) The method according to Supplementary Note 15, wherein executing control to transmit the control signal to the second communication device includes executing transmission control to cause the UE to transmit the control signal before a UE state of the second communication device managed by the UE changes from an active state to an inactive state. (Supplementary Note 18) The method according to Supplementary Note 17, wherein the control signal is a signal for starting or restarting a DRX Inactivity Timer for the UE in the second communication device. (Supplementary Note 19) The method according to Supplementary Note 18, wherein the control signal is a scheduling request. (Supplementary Note 20) The method of Supplementary Note 19, wherein executing control to transmit the control signal to the second communication device includes causing the UE to transmit the scheduling request at the last transmission opportunity of a scheduling request in an active time when the UE state of the second communication device managed by the UE is an active state. (Supplementary Note 21) The method of Supplementary Note 18, wherein the control signal is a Random Access Channel (RACH) signal. (Supplementary Note 22) The method of Supplementary Note 21, wherein executing control to transmit the control signal to the second communication device includes causing the UE to transmit the RACH signal at the last transmission opportunity of a RACH signal in an active time when the UE state of the second communication device managed by the UE is an active state. (Supplementary Note 23) The method of any one of Supplements 16 to 22, wherein the method includes receiving configuration information related to the transmission control from the first communication device or the second communication device. (Supplementary Note 24) The method of Supplementary Note 23, wherein the configuration information is received via Radio Resource Control (RRC).(Supplementary Note 25) The method according to Supplementary Note 15, wherein executing control to transmit the control signal to the second communication device includes executing transmission control to cause a notification signal including information indicating the presence of data addressed to the UE to be transmitted as the control signal to a higher-level device of the first communication device. (Supplementary Note 26) The method according to Supplementary Note 25, wherein the notification signal is a user data frame including a flag indicating the presence of data addressed to the UE and not including the data addressed to the UE.
[0074] This application claims priority based on Japanese Patent Application No. 2023-128204, filed on August 4, 2023, the disclosure of which is incorporated herein by reference in its entirety.
[0075] REFERENCE SIGNS LIST 1 System 10 Communication device 20 Communication device 30 Upper device 40 User equipment (UE) 50 Control device 51 Control unit 60 Control device 61 Control unit
Claims
1. A control device comprising a control means that performs control to send a control signal to the second communication device to keep the UE state managed by the second communication device in an Active state or to change it from an Inactive state to an Active state, when dual connectivity is applied to the first communication device and the second communication device so that multiple packets destined for a user equipment (UE) are distributed to both the first communication device and the second communication device and transmitted to the UE via the first communication device and the second communication device, and when discontinuous reception (DRX) is applied to the communication between the UE and the first communication device and the communication between the UE and the second communication device, and the UE state for the first communication device is in an Active state and the UE state for the second communication device is about to change from an Active state to an Inactive state or has changed it, the control means performs control to send a control signal to the second communication device to keep the UE state managed by the second communication device in an Active state or to change it from an Inactive state to an Active state.
2. The control means executes transmission control to send the control signal to the UE when the amount of data for a packet transmitted to the UE via the first communication device exceeds a threshold, triggered by this condition. The control device according to claim 1.
3. The control means executes a transmission control to cause the control signal to be sent to the UE before the UE state of the second communication device managed by the UE changes from an Active state to an Inactive state. The control device according to claim 1.
4. The control signal is a signal to start or restart the DRX Inactivity Timer for the UE in the second communication device. The control device according to claim 3.
5. The aforementioned control signal is a scheduling request, The control means causes the UE to send the scheduling request during the last opportunity to send a scheduling request in the Active time when the UE state for the second communication device managed by the UE is in the Active state. The control device according to claim 4.
6. The aforementioned control signal is a Random Access Channel (RACH) signal. The control means causes the UE to transmit the RACH signal at the last opportunity to transmit the RACH signal during the Active time when the UE state for the second communication device managed by the UE is in the Active state. The control device according to claim 4.
7. The control means receives configuration information related to the transmission control from the first communication device or the second communication device. The control device according to any one of claims 2 to 6.
8. The control means performs transmission control to cause the host device of the first communication device to transmit a notification signal containing information indicating the existence of data addressed to the UE as the control signal. The control device according to claim 1.
9. The notification signal is a user data frame that includes a flag indicating the existence of data addressed to the UE, but does not include data addressed to the UE. The control device according to claim 8.
10. A method performed by a control device, Dual connectivity is applied to the first and second communication devices so that multiple packets destined for a user equipment (UE) are distributed to both the first and second communication devices and transmitted to the UE via the first and second communication devices, and discontinuous reception (DRX) is applied to the communication between the UE and the first communication device and the communication between the UE and the second communication device, and the UE state for the first communication device is in an Active state and the UE state for the second communication device is about to change from an Active state to an Inactive state or has changed from an Inactive state, the control includes sending a control signal to the second communication device to keep the UE state managed by the second communication device in an Active state or to change it from an Inactive state to an Active state. method.