Communication equipment, base stations, and communication methods

Abstract

To provide user equipment and a communication method capable of appropriately making measurements according to a measurement relaxation method on the basis of, a stationary criterion.MEANS FOR SOLVING THE PROBLEM: User equipment (100) includes: a communication unit (120) that receives, from a serving cell, a stationary threshold value applied to a stationary criterion, which is a criterion used to select whether to make measurements according to a measurement relaxation method that relaxes measurements of radio quality for neighboring cells, and which is a determination criterion for whether the user equipment (100) is in a stationary state; and a control unit (140) that measures at least one of received power and received quality as the radio quality of the serving cell. The control unit (140) determines whether the stationary criterion is met on the basis of, a measurement result of the radio quality and the stationary threshold value.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a user device, a base station, and a communication control method used in a mobile communication system.

Background Art

[0002] In recent years, in 3GPP (3rd Generation Partnership Project), which is a standardization project for mobile communication systems, it has been considered to provide a specific user device having reduced communication capabilities compared to general user devices in a 5G system (see Non-Patent Document 1). The specific user device is a user device having middle-range performance and price for IoT (Internet of Things). For example, compared to general user devices, the maximum bandwidth used for wireless communication is set narrower, or the number of receivers is smaller.

[0003] Also, it has been agreed to introduce a method of relaxing the measurement of radio quality for adjacent cells based on the RSRP (Reference Signal Received Power) / RSRQ (Reference Signal Received Quality) based stationarity criterion for a specific user device in the RRC connected state (so-called RRM relaxation; hereinafter, appropriately referred to as a measurement relaxation method) (see Non-Patent Document 2).

[0004] Since a stationary specific user device has little variation in the radio environment, when a specific user device that does not need to frequently perform the measurement of radio quality for adjacent cells satisfies the stationarity criterion and is regarded as stationary, the number of measurements can be reduced by the measurement relaxation method. Thereby, power saving and improvement of battery life can be achieved.

Prior Art Documents

Non-Patent Documents

[0005] [Non-Patent Document 1] 3GPP contribution “RP-201677” [Non-Patent Document 2] 3GPP contribution R2-2106472” [Overview of the project] [Problems that the invention aims to solve]

[0006] However, the current 3GPP specifications do not include provisions for static standards, raising concerns that certain user equipment may not be able to properly perform measurements in accordance with the measurement relaxation method. Furthermore, similar concerns exist for general user equipment if a measurement relaxation method based on static standards is introduced.

[0007] Therefore, the present invention aims to provide a user device, a base station, and a communication method that enable appropriate measurement according to a measurement relaxation method based on a static standard. [Means for solving the problem]

[0008] A user device according to the first embodiment includes a communication unit that receives a stationary threshold from a serving cell, which is a criterion used to select whether or not to perform a measurement according to a measurement relaxation method that relaxes the measurement of wireless quality to an adjacent cell, and which is a criterion for determining whether or not the user device is in a stationary state; and a control unit that measures at least one of received power and received quality as the wireless quality of the serving cell, wherein the control unit determines whether or not the stationary criterion is met based on the measurement result of the wireless quality and the stationary threshold.

[0009] A base station according to the second embodiment is a base station that manages the serving cell of a user device, and a criterion used to select whether or not to perform a measurement according to a measurement relaxation method that relaxes the measurement of radio quality to adjacent cells, wherein a stationary threshold is applied to a stationary criterion which is a criterion for determining whether or not the user device is in a stationary state, and the radio resource controlThe system includes a control unit that includes the RRC message, and a wireless communication unit that transmits the RRC message to the user device.

[0010] A third aspect of the communication control method is a communication control method performed by a user device, comprising the steps of: receiving a stationary threshold from a serving cell, which is a criterion used to select whether or not to perform a measurement according to a measurement relaxation method that relaxes the measurement of radio quality for adjacent cells, and which is a criterion for determining whether or not the user device is in a stationary state; measuring at least one of received power and received quality as the radio quality of the serving cell; and determining whether or not the stationary criterion is met based on the measurement result of the radio quality and the stationary threshold. [Effects of the Invention]

[0011] According to one aspect of the present invention, a user device and a communication method can be provided that enable appropriate measurement according to a measurement relaxation method based on a static reference. [Brief explanation of the drawing]

[0012] [Figure 1] This diagram shows the configuration of a mobile communication system according to an embodiment. [Figure 2] This figure shows an example of the configuration of a protocol stack according to the embodiment. [Figure 3] This is a diagram showing the configuration of the UE according to the embodiment. [Figure 4] This is a diagram showing the configuration of a base station according to the embodiment. [Figure 5] This is a sequence diagram illustrating the first and third operation examples of the mobile communication system according to the embodiment. [Figure 6] This figure shows an example of information according to the embodiment. [Figure 7] This figure shows an example of information according to the embodiment. [Figure 8] This is a diagram illustrating a first example of operation of a mobile communication system according to an embodiment. [Figure 9] This is a diagram illustrating a first example of operation of a mobile communication system according to an embodiment. [Figure 10] This is a diagram illustrating a first example of operation of a mobile communication system according to an embodiment. [Figure 11] This is a diagram illustrating a first example of operation of a mobile communication system according to an embodiment. [Figure 12] This is a sequence diagram illustrating a second example of operation of the mobile communication system according to the embodiment. [Figure 13] This figure shows an example of information according to the embodiment. [Figure 14] This is a diagram illustrating a first example of operation of a mobile communication system according to an embodiment. [Figure 15] This figure shows an example of information according to the embodiment. [Figure 16] This is a diagram illustrating a third example of operation of the mobile communication system according to the embodiment. [Figure 17] This figure shows an example of information according to the embodiment. [Figure 18] This is a diagram illustrating a fourth example of operation of the mobile communication system according to the embodiment. [Figure 19] This figure shows an example of information according to the embodiment. [Figure 20] This is a sequence diagram illustrating a fifth example of operation of the mobile communication system according to the embodiment. [Figure 21] This is a diagram illustrating a fifth example of operation of the mobile communication system according to the embodiment. [Figure 22] This is a diagram illustrating a fifth example of operation of the mobile communication system according to the embodiment. [Modes for carrying out the invention]

[0013] A mobile communication system according to an embodiment will be described with reference to the drawings. In the drawings, identical or similar parts are denoted by the same or similar reference numerals.

[0014] (System Configuration) First, the configuration of the mobile communication system 1 according to this embodiment will be described with reference to Figure 1. The mobile communication system 1 is, for example, a system that conforms to the 3GPP Technical Specification (TS). In the following, the mobile communication system 1 will be described using the 5th Generation System (5GS) of the 3GPP standard, that is, a mobile communication system based on NR (New Radio), as an example.

[0015] The mobile communication system 1 includes a network 10 and user equipment (UE) 100 that communicates with the network 10. The network 10 includes a 5G radio access network, NG-RAN (Next Generation Radio Access Network) 20, and a 5G core network, 5GC (5G Core Network) 30.

[0016] UE100 is a device used by a user. UE100 is a mobile device such as a smartphone or other mobile phone terminal, tablet terminal, notebook PC, communication module, or communication card. UE100 may be a vehicle (e.g., car, train, etc.) or a device installed therein. UE100 may be a transport vehicle other than a vehicle (e.g., ship, airplane, etc.) or a device installed therein. UE100 may be a sensor or a device installed thereon. Note that UE100 may also be referred to by other names such as mobile station, mobile terminal, mobile device, mobile unit, subscriber station, subscriber terminal, subscriber device, subscriber unit, wireless station, wireless terminal, wireless device, wireless unit, remote station, remote terminal, remote device, or remote unit.

[0017] In this embodiment, two types of UEs are assumed for the NR UE100: a general UE100A and a specific UE100B which has reduced communication capabilities compared to the general UE100A. The general UE100A has advanced communication capabilities such as high speed and large capacity (enhanced Mobile Broadband: eMBB) and ultra-reliable and low latency communications (URLLC), which are characteristics of NR. The specific UE100B is a UE with reduced equipment cost and complexity compared to the general UE100A. The specific UE100B is a UE100 with mid-range performance and price for IoT, and for example, compared to the general UE100A, the maximum bandwidth used for wireless communication is set narrower and the number of receivers is smaller. The receivers are sometimes referred to as receiving branches. The specific UE100B is sometimes referred to as a Reduced capability NR device or RedCap UE.

[0018] Specifically, a specific UE100B may be capable of communicating at a communication speed greater than or equal to the communication speed specified in LPWA (Low Power Wide Area) standards, such as LTE Cat.1 / 1bis, LTE Cat.M1 (LTE-M), and LTE Cat.NB1 (NB-IoT). A specific UE100B may be capable of communicating with a bandwidth greater than or equal to the bandwidth specified in the LPWA standard. A specific UE100B may have a limited bandwidth used for communication compared to a Rel-15 or Rel-16 UE. For example, for FR1 (Frequency Range 1), the maximum bandwidth of a specific UE100B may be 20MHz. Also, for FR2 (Frequency Range 2), for example, the maximum bandwidth of a specific UE100B may be 100MHz. A specific UE100B may have only one receiver for receiving radio signals. A specific UE100B may be, for example, a wearable device or a sensor device.

[0019] NG-RAN20 includes multiple base stations 200. Each base station 200 manages at least one cell. A cell constitutes the smallest unit of a communication area. A single cell belongs to a single frequency (carrier frequency). The term "cell" may represent a radio communication resource, or it may represent a communication target of the UE100. Each base station 200 can communicate wirelessly with UE100s located within its own cell. The base station 200 communicates with the UE100 using the RAN's protocol stack. Details of the protocol stack will be described later. The base station 200 is also connected to other base stations 200 (which may be called adjacent base stations) via the Xn interface. The base station 200 communicates with adjacent base stations via the Xn interface. The base station 200 also provides NR user plane and control plane protocol terminations directed to the UE100 and is connected to the 5GC30 via the NG interface. Such NR base stations 200 are sometimes referred to as gNodeB (gNB).

[0020] 5GC30 includes a core network device 300. The core network device 300 includes, for example, an AMF (Access and Mobility Management Function) and / or a UPF (User Plane Function). The AMF manages the mobility of the UE100. The UPF provides functions specifically for U-plane processing. The AMF and UPF are connected to the base station 200 via an NG interface.

[0021] (Example of protocol stack configuration) Next, with reference to Figure 2, an example of the protocol stack configuration according to this embodiment will be described.

[0022] The protocol for the radio section between UE100 and base station 200 has a physical (PHY) layer, a MAC (Medium Access Control) layer, an RLC (Radio Link Control) layer, a PDCP (Packet Data Convergence Protocol) layer, and an RRC layer.

[0023] The PHY layer performs coding and decoding, modulation and demodulation, antenna mapping and demapping, and resource mapping and demapping. Data and control information are transmitted between the PHY layer of UE100 and the PHY layer of base station 200 via a physical channel.

[0024] The MAC layer performs data priority control, retransmission processing using Hybrid ARQ (HARQ), and random access procedures. Data and control information are transmitted between the MAC layer of UE100 and the MAC layer of base station 200 via the transport channel. The MAC layer of base station 200 includes a scheduler. The scheduler determines the transport format for the uplink and downlink (transport block size, modulation coding scheme (MCS)) and the resources to be allocated to UE100.

[0025] The RLC layer transmits data to the receiving RLC layer by utilizing the functions of the MAC layer and PHY layer. Data and control information are transmitted between the RLC layer of UE100 and the RLC layer of base station 200 via a logical channel.

[0026] The PDCP layer performs header compression / decompression, and encryption / decryption.

[0027] An SDAP (Service Data Adaptation Protocol) layer may be provided as a layer above the PDCP layer. The SDAP layer maps IP flows, which are the units in which the core network performs QoS control, to wireless bearers, which are the units in which the AS (Access Stratum) performs QoS control.

[0028] The RRC layer controls the logical channel, transport channel, and physical channel in response to the establishment, re-establishment, and release of the radio bearer. RRC signaling for various settings is transmitted between the RRC layer of UE100 and the RRC layer of base station 200. If there is an RRC connection between the RRC of UE100 and the RRC of base station 200, UE100 is in the RRC connected state. If there is no RRC connection between the RRC of UE100 and the RRC of base station 200, UE100 is in the RRC idle state. If the RRC connection between the RRC of UE100 and the RRC of base station 200 is suspended, UE100 is in the RRC inactive state.

[0029] In UE100, the NAS layer, located above the RRC layer, handles session management and mobility management for UE100. NAS signaling is transmitted between the NAS layer of UE100 and the NAS layer of the core network device 300.

[0030] In addition to the wireless interface protocol, the UE100 also has an application layer and other components.

[0031] (User device configuration) Next, the configuration of the UE100 according to this embodiment will be described with reference to Figure 3. The UE100 includes a communication unit 120 and a control unit 140.

[0032] The communication unit 120 performs wireless communication with the base station 200 by transmitting and receiving radio signals to and from the base station 200. The communication unit 120 has at least one receiving unit 121 and at least one transmitting unit 122. The receiving unit 121 and the transmitting unit 122 may include an antenna and an RF circuit. The antenna converts a signal into radio waves and radiates the radio waves into space. The antenna also receives radio waves in space and converts the radio waves into signals. The RF circuit performs analog processing of the signals transmitted and received via the antenna. The RF circuit may include a high-frequency filter, an amplifier, a modulator, and a low-pass filter, etc.

[0033] The receiving unit 121 may be called a receiver (RX). The transmitting unit 122 may be called a transmitter (TX). If the UE100 is a general UE100A, the number of receivers in the communication unit 120 may be two to four. If the UE100 is a specific UE100B, the number of receivers in the communication unit 120 may be one or two.

[0034] The control unit 140 performs various controls on the UE 100. The control unit 140 controls communication with the base station 200 via the communication unit 120. The operation of the UE 100, described later, may be an operation controlled by the control unit 140. The control unit 140 may include at least one program-executable processor and memory for storing the program. The processor may execute the program to perform the operation of the control unit 140. The control unit 140 may include a digital signal processor that performs digital processing of signals transmitted and received via the antenna and RF circuit. This digital processing includes processing of the RAN protocol stack. The memory stores the program executed by the processor, parameters related to the program, and data related to the program. The memory may include at least one of ROM (Read Only Memory), EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable Programmable Read Only Memory), RAM (Random Access Memory), and flash memory. All or part of the memory may be contained within the processor.

[0035] In the UE100 configured in this way, the communication unit 120 receives from the serving cell a stationary threshold, which is a criterion used to select whether or not to perform a measurement according to a measurement relaxation method that relaxes the measurement of radio quality for adjacent cells, and which is a criterion for determining whether or not the UE100 is in a stationary state. The control unit 140 measures at least one of the received power and received quality as the radio quality of the serving cell. Based on the measurement result of the radio quality and the stationary threshold, the control unit 140 determines whether or not the stationary criterion is met. As a result, the control unit 140 can appropriately perform a measurement according to the measurement relaxation method by determining whether or not the stationary criterion is met based on the measurement result of the radio quality and the stationary threshold.

[0036] The control unit 140 may determine whether the static criterion is met based on the quality threshold, regardless of whether the static threshold includes a power threshold that is compared with a value calculated based on the received power, if the static threshold includes a quality threshold that is compared with a value calculated based on the received power. This allows for a determination of whether the static criterion is met, taking into account the effects of communication quality due to interference and noise, compared to, for example, determining whether the static criterion is met based on the received power.

[0037] The control unit 140 may determine whether the static criterion is met based on the quality threshold and the power threshold if the static threshold includes a quality threshold compared with a value calculated based on reception quality and a power threshold compared with a value calculated based on reception power. This allows the determination of whether the static criterion is met based on both reception quality and reception power, thus preventing the static criterion from being met when the wireless quality is poor. Therefore, measurements according to the measurement relaxation method can be performed appropriately.

[0038] If the quiescent threshold includes a power threshold but not a quality threshold, the control unit 140 may determine whether the quiescent criterion is met based on the power threshold. This allows for appropriate determination of the quiescent state based solely on the received power in environments such as isolated cells, where there is no interference from neighboring cells and the cell's own traffic is low.

[0039] If the communication unit 120 determines that the quiescing criteria have been met, it may send a message to the serving cell indicating that the quiescing criteria have been met. This allows the network to know that the UE 100 has met the quiescing criteria.

[0040] If the control unit 140 determines that the static criteria are met, it may choose to perform measurements on adjacent cells according to the measurement relaxation method. This allows the UE 100 to perform measurements on adjacent cells according to the measurement relaxation method.

[0041] The communication unit 120 includes wireless resources including a static threshold. control The (RRC) message may be received from the serving cell. This allows the network to control measurements according to the measurement relaxation method.

[0042] The communication unit 120 may further receive from the serving cell a low mobility threshold that is applied to a low mobility criterion indicating that the user device is in a low mobility state. The stationary threshold may differ from the low mobility threshold.

[0043] Furthermore, the control unit 140 determines whether or not the static criterion, which is a criterion for determining whether or not the UE 100 is in a stationary state, is met, which is used to select whether or not to perform the measurement according to a measurement relaxation method that relaxes the measurement of wireless quality to adjacent cells. The communication unit 120, in response to the meeting of the static criterion, provides a wireless resource indicating that the static criterion has been met. control The (RRC) message is sent to the network. This allows the network to know from the RRC message that the quiescent criterion has been met at UE100. Based on this, the network can then perform measurements according to the measurement relaxation method, based on the fact that the user equipment has met the quiescent criterion.

[0044] The RRC message may be a measurement report message for transmitting the measurement results of wireless quality to the network. The network can learn from the measurement report message not only that the static criteria have been met, but also the measurement results.

[0045] The control unit 140 may include the measurement identifier associated with the static event identifier in the measurement report message when the conditions for joining a static event, which indicate that the static criteria have been met, are met. This allows the network to know that the conditions for joining a static event have been met based on the measurement identifier.

[0046] The RRC message may be a UE supplementary information message used to indicate information about UE100 to the network. This allows the network to know that the quiescent criteria have been met through the UE supplementary information message.

[0047] The control unit 140 may include status information in the UE auxiliary information message indicating that the UE 100 is in a stationary state. This allows the network to know that the UE 100 is in a stationary state.

[0048] The communication unit 120 may receive configuration information from the network for providing status information to the network. The control unit 140 may start sending a UE auxiliary information message if it has not sent one since receiving the configuration information. As a result, the network can know the quiescent state of the UE 100 by sending the configuration information to the UE 100.

[0049] If the control unit 140 found that the last UE auxiliary information message sent to the network contained status information indicating that the UE 100 was not in a quiescent state, it may start sending a UE auxiliary information message in response to the quiescent criteria being met. This allows the network to know that the quiescent criteria have been met for the UE 100, which is not in a quiescent state.

[0050] The control unit 140 may start the prohibit timer in response to the transmission of a UE auxiliary information message containing status information. The communication unit 120 does not need to transmit the next UE auxiliary information message containing status information if the prohibit timer is running. This reduces the increase in signaling when the UE 100's quiescent state switches frequently in a short period of time, as it does not need to transmit an RRC message each time the state switches.

[0051] The control unit 140 determines whether or not the static criterion is met, which is a criterion used to select whether or not to perform a measurement according to a measurement relaxation method that relaxes the measurement of wireless quality to adjacent cells, and is a criterion for determining whether or not the UE 100 is in a static state. The communication unit 120 transmits a radio resource management (RRC) message to the network indicating that the static criterion is no longer met, in response to the static criterion no longer being met. This allows the network to know that the static criterion is no longer being met.

[0052] The control unit 140 may include the measurement identifier associated with the static event identifier in the measurement report message when it has met the conditions for leaving a static event, which indicate that the static criteria have been met. This allows the network to know that the conditions for leaving a static event have been met based on the measurement identifier.

[0053] The control unit 140 may include status information in the UE auxiliary information message indicating that the UE 100 is not in a stationary state. This allows the network to know that the UE 100 is not in a stationary state.

[0054] If the last UE auxiliary information message sent to the network by the control unit 140 included status information indicating that the UE 100 was in a quiescent state, the control unit 140 may start sending a UE auxiliary information message in response to the fact that the quiescent criteria are no longer met. This allows the network to know that the quiescent criteria are no longer met for the UE 100, which was in a quiescent state.

[0055] The control unit 140 determines whether the following criteria are met: a stationary criterion, which is a criterion used to select whether or not to perform a measurement according to a measurement relaxation method that relaxes the measurement of radio quality for adjacent cells, and is a criterion for determining whether or not the UE 100 is in a stationary state; and a non-cell edge criterion, which is a criterion used to select whether or not to perform a measurement according to the measurement relaxation method, and is a criterion for determining whether or not the UE 100 is in a non-cell edge state and is not at the cell edge of the serving cell. The communication unit 120, in response to both the stationary criterion and the non-cell edge criterion being met, provides a radio resource indicating that both the stationary criterion and the non-cell edge criterion have been met. control A (RRC) message is sent to the network. This allows the network to know that both the quiescent criterion and the non-cell edge criterion have been met.

[0056] The control unit 140 may include a measurement identifier associated with the identifiers of the static and non-cell edge events in the measurement report message when the conditions for joining static and non-cell edge events, which indicate that both the static criterion and the non-cell edge criterion are met, are met. This allows the network to know, based on the measurement identifier, that the conditions for joining static and non-cell edge events have been met.

[0057] The control unit 140 may include status information in the UE auxiliary information message indicating that the UE 100 is in a stationary state and is not at a cell edge. This allows the network to know that the UE 100 is in a stationary state and is not at a cell edge.

[0058] If the last UE auxiliary information message sent to the network by the control unit 140 contains status information indicating that the UE 100 is not in a quiescent state or not in a non-cell edge state, the control unit 140 may start sending a UE auxiliary information message in response to the fact that both the quiescent criterion and the non-cell edge criterion have been met. This allows the network to know that both the quiescent criterion and the non-cell edge criterion have been met for the UE 100, which is not in a quiescent state or not in a non-cell edge state.

[0059] The control unit 140 determines whether the following criteria are met: a stationary criterion, which is used to select whether or not to perform a measurement according to a measurement relaxation method that relaxes the measurement of wireless quality for adjacent cells, and is a criterion for determining whether or not the UE 100 is in a stationary state; and a non-cell edge criterion, which is used to select whether or not to perform a measurement according to the measurement relaxation method, and is a criterion for determining whether or not the UE 100 is in a non-cell edge state and is not at the cell edge of the serving cell. The communication unit 120 transmits a radio resource management (RRC) message to the network indicating that at least one of the stationary criterion and the non-cell edge criterion is no longer met. This allows the network to know that at least one of the stationary criterion and the non-cell edge criterion is no longer met.

[0060] The control unit 140 may include the measurement identifier associated with the identifiers of the stationary and non-cell edge events in the measurement report message when the conditions for departing from stationary and non-cell edge events, which indicate that both the stationary criterion and the non-cell edge criterion have been met, are satisfied. This allows the network to know that the conditions for departing from stationary and non-cell edge events have been met based on the measurement identifier.

[0061] The control unit 140 may include status information in the UE auxiliary information message indicating that the UE 100 is not in a stationary state or is not in a non-cell edge state. This allows the network to know that the UE 100 is not in a stationary state or is not in a non-cell edge state.

[0062] If the last UE auxiliary information message sent to the network by the control unit 140 contains status information indicating that the UE 100 is in a quiescent state and is not at a cell edge, the control unit 140 may start sending a UE auxiliary information message in response to the fact that at least one of the quiescent criterion and the not-at-cell edge criterion is no longer met. This allows the network to know that at least one of the quiescent criterion and the not-at-cell edge criterion is no longer met for the UE 100, which is in a quiescent state and not at a cell edge.

[0063] In addition, the operation of the functional units of the UE100 (specifically, at least one of the communication unit 120 and the control unit 140) may be described as the operation of the UE100.

[0064] (Base station configuration) Next, with reference to Figure 4, the configuration of the base station 200 according to this embodiment will be described. The base station 200 has a wireless communication unit 220, a network communication unit 230, and a control unit 240.

[0065] The wireless communication unit 220, for example, receives a wireless signal from the UE 100 and transmits a wireless signal to the UE 100. The wireless communication unit 220 may include one or more receiving units for receiving wireless signals and one or more transmitting units for transmitting wireless signals.

[0066] The network communication unit 230 transmits and receives signals to and from the network. For example, the network communication unit 230 receives signals from an adjacent base station connected via the Xn interface, which is an inter-base station interface, and transmits signals to the adjacent base station. The network communication unit 230 also receives signals from a core network device 300 connected via the NG interface, and transmits signals to the core network device 300.

[0067] The control unit 240 performs various controls on the base station 200. For example, the control unit 240 controls communication with the UE 100 via the wireless communication unit 220. The control unit 240 also controls communication with nodes (e.g., adjacent base stations, core network devices 300) via the network communication unit 230. The operation of the base station 200, as described later, may be controlled by the control unit 240.

[0068] The control unit 240 may include at least one processor capable of executing a program and a memory for storing the program. The processor may execute the program to operate the control unit 240. The control unit 240 may also include a digital signal processor that performs digital processing of signals transmitted and received via the antenna and RF circuit. This digital processing includes processing of the RAN protocol stack. The memory stores the program executed by the processor, parameters related to the program, and data related to the program. All or part of the memory may be contained within the processor.

[0069] In the base station 200 configured in this way, the control unit 240 uses a criterion used to select whether or not to perform a measurement according to a measurement relaxation method that relaxes the measurement of radio quality for adjacent cells, and applies a stationary threshold to a stationary criterion which is a criterion for determining whether or not the UE 100 is stationary, to the radio resource control The (RRC) message is included. The wireless communication unit 220 transmits the RRC message to the user device. This allows the network to control the measurement according to the measurement relaxation method.

[0070] Furthermore, the wireless communication unit 220 uses a criterion used to select whether or not to perform a measurement according to a measurement relaxation method that relaxes the measurement of wireless quality for adjacent cells, and the wireless resource indicates that the static criterion, which is the criterion for determining whether or not the UE 100 is in a stationary state, has been met. control The (RRC) message is received from UE100. The control unit 240 controls the measurement of UE100 according to the measurement relaxation method. The network can know from the RRC message that the quiescent criterion has been met in UE100. This allows the network to control the measurement of UE100 according to the measurement relaxation method based on the quiescent criterion.

[0071] The wireless communication unit 220 may transmit the stationary threshold applied to the stationary criterion to the UE 100. This allows the network to control measurements according to the measurement relaxation method based on the stationary criterion.

[0072] The wireless communication unit 220 uses a criterion used to select whether or not to perform a measurement according to a measurement relaxation method that relaxes the measurement of wireless quality to adjacent cells, and indicates that the static criterion, which is the criterion for determining whether or not the UE 100 is in a stationary state, is no longer met. control The (RRC) message is received from UE100. The control unit 240 controls the measurement of UE100 according to the measurement relaxation method. The network can know from the RRC message that the quiescent criterion is no longer met in UE100. This allows the network to control the measurement of UE100 according to the measurement relaxation method based on the quiescent criterion.

[0073] The wireless communication unit 220 provides a wireless resource that indicates that the following criteria have been met: a static criterion used to select whether or not to perform a measurement according to a measurement relaxation method that relaxes the measurement of wireless quality for adjacent cells, which is used to select whether or not to perform a measurement according to the measurement relaxation method and is used to determine whether or not the UE 100 is in a non-cell edge state where it is not at the cell edge of the serving cell; and a non-cell edge criterion used to select whether or not to perform a measurement according to the measurement relaxation method and is used to determine whether or not the UE 100 is in a non-cell edge state where it is not at the cell edge of the serving cell. control The (RRC) message is received from UE100. The control unit 240 controls the measurement of UE100 according to the measurement relaxation method. This allows the network to control the measurement of UE100 according to the measurement relaxation method.

[0074] The wireless communication unit 220 may transmit to the UE 100 a static threshold applicable to the static criterion and a non-cell edge threshold applicable to the non-cell edge criterion. This allows the network to control measurements according to measurement relaxation methods based on the static criterion and the non-cell edge criterion.

[0075] The wireless communication unit 220 indicates that at least one of the following criteria is no longer met: a static criterion, which is a criterion for determining whether or not the UE 100 is in a stationary state, and a non-cell edge criterion, which is a criterion for determining whether or not the UE 100 is in a non-cell edge state, which is a criterion for determining whether or not the UE 100 is not at the cell edge of the serving cell, and is used to select whether or not to perform a measurement according to a measurement relaxation method that relaxes the measurement of wireless quality for adjacent cells. control The (RRC) message is received from UE100. The control unit 240 controls the measurement of UE100 according to the measurement relaxation method. This allows the network to control the measurement of UE100 according to the measurement relaxation method based on the static reference and the non-cell edge reference. .

[0076] In addition, the operation of the functional units of the base station 200 (specifically, at least one of the wireless communication unit 220, the network communication unit 230, and the control unit 240) may be described as the operation of the base station 200.

[0077] (System operation) (1) First example of operation Referring to Figures 5 to 11, a first operational example of the mobile communication system 1 will be described. In this first operational example, the case in which UE100 transmits a measurement report message to base station 200 depending on whether or not the stationary criteria have been met will be described.

[0078] As shown in Figure 5, UE100 is in an RRC connected state with base station 200. Therefore, UE100 has established an RRC connection with cell (serving cell) C managed by base station 200.

[0079] In the following, communication between UE100 and base station 200 may be referred to as communication between UE100 and the serving cell. Similarly, communication (transmission and / or reception) between UE100 and base station 200 may be referred to as communication (transmission and / or reception) between UE100 and the network.

[0080] Step S101: The wireless communication unit 220 of the base station 200 transmits configuration information to the UE 100. The communication unit 120 of the UE 100 receives configuration information from the base station 200 (serving cell).

[0081] The wireless communication unit 220 contains wireless resources including configuration information. control (RRC) messages can be sent to UE100. Therefore, configuration information may be transmitted by broadcast using a system information block (e.g., SIB2). Alternatively, configuration information may be sent individually to UE100 using RRC reset messages or the like.

[0082] In this example, the configuration information includes information for setting up measurement reports to UE100. The configuration information may include NR report configuration information (ReportConfigNR) that specifies the criteria for triggering measurement report events. As shown in Figures 6 and 7, the NR report configuration information (ReportConfigNR) may include measurement type information (reportType) that indicates the type of measurement report to be set. The measurement type information (reportType) may include relaxation trigger information (relaxedMeasEventTriggered) used by UE100 to report that the relaxation measurement conditions have been met. The relaxation trigger information may include an event identifier (eventId) that indicates the trigger criteria for the report. The event identifier (eventId) may indicate a static event (eventS1). The event identifier may indicate static and non-cell edge events (eventS2), which will be described later.

[0083] The event identifier (eventId) may include a static threshold T1 applied to the static criterion. Thus, the control unit 240 of the base station 200 can include the static threshold T1 in the RRC message. This allows the communication unit 120 of the UE 100 to receive the static threshold T1 from the serving cell. The static threshold T1 may include at least one of a power threshold (s-SearchDeltaP-Stationary) compared to a value calculated based on the received power measured as radio quality for the serving cell, and a quality threshold (s-SearchDeltaQ-Stationary) compared to a value calculated based on the received quality measured as radio quality for the serving cell. The power threshold (s-SearchDeltaP-Stationary) is described below as S SearchDeltaP_stationary It is acceptable. S SearchDeltaP_stationary This specifies the threshold for the variation in the received level value (Srxlev) for relaxation measurement. The received level value (Srxlev) may be the received level value for cell selection (Cell selection RX level value). The quality threshold (s-SearchDeltaQ-Stationary) is as described below. SearchDeltaQ_stationary It is acceptable. S SearchDeltaQ_stationary This specifies the threshold for variation in the quality value (Squal) used for relaxation measurement. The quality value (Squal) may be the cell selection quality value.

[0084] Furthermore, the event identifier (eventId) may include period information (t-SearchDeltaP-Stationary) that specifies a predetermined period over which fluctuations in the received level value (Srxlev) are evaluated. The period information (t-SearchDeltaP-Stationary) is described below in T SearchDeltaP_stationary This may be the case. Additionally, the event identifier (eventId) may include reportOnLeave information indicating whether UE100 should initiate the measurement reporting procedure when the departure conditions are met for a serving cell.

[0085] The relaxed MeasEventTriggered information may include reportInterval information, which indicates the interval between measurement reports to be applied to the relaxed MeasEventTriggered information. The relaxed MeasEventTriggered information may also include reportAmount information, which indicates the number of measurement reports to be applied to the relaxed MeasEventTriggered information.

[0086] The configuration information may include measurement configuration information (MeasConfig) that specifies the measurements to be performed by the UE100. The configuration information may include a MeasObjectToAddMod, which relates to a list for adding or changing the objects to be measured. The MeasObjectToAddMod may include an NR MeasObjectNR, which specifies information applicable to in-frequency / inter-frequency measurements and / or CSI-RS in-frequency / inter-frequency measurements of SS (Synchronization Signal) / PBCH (Physical Broadcast Channel) blocks.

[0087] The configuration information may include a list of measurement identifiers (measIdList / MeasIdToAddModList) related to a list for adding or changing measurement identifiers. The list of measurement identifiers may include a measurement identifier (measId), a measurement object identifier (measObjectId), and a report configuration identifier (ReportConfigId). The measurement identifier (measId), measurement object identifier (measObjectId), and report configuration identifier (ReportConfigId) are associated with each entry.

[0088] The configuration information may include a report configuration list (reportConfigList / ReportConfigToAddModList) for a list of report configurations to add or modify. The report configuration list may include a report configuration identifier (reportConfigId) and report configuration information (reportConfig). The report configuration information (reportConfig) may include NR report configuration information (ReportConfigNR).

[0089] The configuration information may include a low mobility threshold applied to the low mobility criterion that indicates the UE100 is in a low mobility state. This allows the UE100 to receive the low mobility threshold from the serving cell. The low mobility threshold specifies the threshold for Srxlev for relaxation measurements. SearchThresholdP This may be the case. The low mobility threshold specifies the threshold for Squal for relaxation measurements. SearchThresholdQ This may be the case. The stationary threshold T1 is different from the low mobility threshold. The minimum setting value for the stationary threshold T1 may be lower than the minimum setting value for the low mobility threshold.

[0090] The control unit 140 of UE100 sets the information included in the configuration information. Based on the set information, UE100 can perform the following operations.

[0091] Step S102: The control unit 140 of the UE100 performs measurement and determination. Specifically, the control unit 140 measures at least one of the received power and received quality as the radio quality of the serving cell. The received power may be RSRP (Reference Signal Received Power). The received quality may be RSRQ (Reference Signal Received Quality). The control unit 140 measures the radio quality by measuring the reference signal (RS) from the serving cell.

[0092] The control unit 140 of UE100 determines whether the static criterion is met based on the measurement result of the wireless quality and the static threshold T1. The static criterion is a criterion used to select whether or not to perform the measurement according to a measurement relaxation method that relaxes the measurement of wireless quality for adjacent cells, and is a criterion for determining whether or not UE100 is in a static state. The control unit 140 may use either the first method or the second method as a method for determining whether or not the static criterion is met.

[0093] In the first method, when the stationary threshold T1 includes the quality threshold, the control unit 140 may determine whether the stationary criterion is satisfied based on the quality threshold regardless of whether the stationary threshold T1 includes the power threshold. As shown in E1 of FIG. 8, when the stationary threshold T1 includes the quality threshold, that is, when S SearchDeltaQ_stationary is set as the quality threshold for the UE100, as the stationary criterion, it may be determined whether the following formula is satisfied. The control unit 140 applies the set S SearchDeltaQ_stationary to the following stationary criterion. (Squal Ref - Squal) < S SearchDeltaQ_stationary

[0094] Squal is the current Squal value of the serving cell. Squal Ref is the reference Squal value of the serving cell. The reference Squal value is (i) after selection or reselection of a new cell, (ii) when (Squal - Squal Ref ) > 0 is satisfied, or (iii) when the stationary criterion has not been satisfied for a predetermined period (T SearchDeltaP_stationary ), the control unit 140 of the UE100 may set the current Squal value of the serving cell to Squal Ref .

[0095] Note that the Squal value is calculated by the following formula. Squal = Q qualmeas - (Q qualmin + Q qualminoffset ) - Qoffset<00000​​​​​​​​​​​​​​​Furthermore, if the quiescent threshold T1 includes a power threshold but does not include a quality threshold, the control unit 140 may determine whether the quiescent criterion is met based on the power threshold. As shown in E2 of Figure 8, if the quiescent threshold T1 includes a power threshold but does not include a quality threshold, the control unit 140 may determine whether the following equation is met as the quiescent criterion. The control unit 140 determines whether the set S SearchDeltaP_stationary The following static criteria are applied. (Srxlev Ref - Srxlev) < S SearchDeltaP_stationary

[0098] Srxlev is the current Srxlev value of the serving cell. Ref This is the base Srxlev value of the serving cell. The base Srxlev value is (i) after selecting or re-selecting a new cell, and (ii) (Srxlev - Srxlev Ref ) > 0 if (iii) the static criterion is met for a specified period (T SearchDeltaP_stationary If not satisfied, the control unit 140 of UE100 will Srxlev Ref You may set the current Srxlev value of the serving cell to this value.

[0099] The Srxlev value is calculated using the following formula. Srxlev = Q rxlevmeas - (Q rxlevmin + Q rxlevminoffset )- P compensation - Qoffset temp

[0100] Q rxlevmeas This is the measured received power (RSRP) of the cell. Q rxlevmin Q is the minimum required received power. rxlevminoffset This is a predetermined offset that is applied on a regular basis. compensation This is a parameter related to the uplink's capability. Qoffset temp This is a temporary offset.

[0101] In the second method, if the quiescent threshold T1 includes a quality threshold and a power threshold, the control unit 140 may determine whether the quiescent criterion is met based on the quality threshold and the power threshold. As shown in E3 of Figure 9, if the quiescent threshold T1 includes a quality threshold and a power threshold, that is, if the UE100 has a quality threshold, S SearchDeltaQ_stationary The power threshold for UE100 is set to S SearchDeltaP_stationary If the set S, the control unit 140 may determine whether the following equation is satisfied as the static criterion. SearchDeltaQ_stationary and S SearchDeltaP_stationary The following static criteria are applied. (Srxlev Ref - Srxlev) < S SearchDeltaP_stationary and (Squal Ref - Squal) < S SearchDeltaQ_stationary

[0102] Furthermore, if the quiescent threshold T1 includes a power threshold but does not include a quality threshold, the control unit 140 may determine whether the quiescent criterion is met based on the power threshold. As shown in E4 of Figure 9, if the quiescent threshold T1 includes a power threshold but does not include a quality threshold, the control unit 140 may determine whether the following equation is met as the quiescent criterion. The control unit 140 sets S SearchDeltaP_stationary The following static criteria are applied. (Srxlev Ref - Srxlev) < S SearchDeltaP_stationary

[0103] As shown in A1 of Figure 10, the control unit 140 may consider that the conditions for joining a quiescent event have been met if condition S1-1 is met. Condition S1-1 is that (i) UE100 has been at least a predetermined period (T) after handover to a serving cell or after (re)establishment of the RRC connection to a serving cell. SearchDeltaP_stationary (ii) having performed normal radio quality measurements for cells within a frequency, normal radio quality measurements for cells between NR frequencies, or normal radio quality measurements for cells between RATs, and (ii) for a specified period (T SearchDeltaP_stationary ), the static criterion may be met.

[0104] As shown in A2 of Figure 10, the control unit 140 may consider that the condition for leaving the stationary event has been met if condition S1-2 is met. Condition S1-2 is that after the joining condition is met, a predetermined period (T SearchDeltaP_stationary ), or the static criterion is no longer met.

[0105] As shown in A3 of Figure 10, the control unit 140 may target the serving cell corresponding to the NR measurement target (MeasObjectNR) associated with the stationary event for this measurement.

[0106] Furthermore, as shown in B1 of Figure 11, in UE100, if, with respect to each measurement identifier (measId) included in the measurement identifier list (measIdList) contained within the variable measurement setting information (VarMeasConfig), the corresponding report setting information (reportConfig) includes the measurement type information (reportType) set in the relaxation trigger information (relaxedMeasEventTriggered), and the corresponding measurement target information (measObject) is related to NR, then UE100 may be considered to apply only to serving cells.

[0107] As shown in B2 of Figure 11, if the variable measurement report list (VarMeasReportList) does not contain a measurement report entry for this measurement identifier, but the measurement type information (reportType) is set to relaxed trigger information (relaxedMeasEventTriggered) and the conditions for joining the event indicated by the event identifier are met, the control unit 140 of UE100 may perform the following actions. Note that the variable measurement report list (VarMeasReportList) for each measurement identifier may include the measurement identifier (measId), the cell trigger list (cellsTriggeredList), and the number of reports information (numberOfReportsSent).

[0108] The control unit 140 may include a measurement report entry in the variable measurement report list (VarMeasReportList) for this measurement identifier. The control unit 140 may set the number of reports (numberOfReportsSent) defined in the variable measurement report list (VarMeasReportList) for this measurement identifier to 0. The control unit 140 may include serving cell information in the cell triggered list (cellsTriggeredList) defined in the variable measurement report list (VarMeasReportList) for this measurement identifier. The control unit 140 may also start the measurement reporting procedure.

[0109] In the following explanation, we will proceed assuming that the control unit 140 has determined that the stationary criteria have been met, specifically that the conditions for joining a stationary event have been met.

[0110] Step S103: The communication unit 120 of UE100 transmits a measurement report message to the serving cell (base station 200, network). The wireless communication unit 220 of base station 200 receives the measurement report message.

[0111] The communication unit 120 can send a measurement report message to the serving cell (network) when the static criteria are met. The measurement report message may indicate that the static criteria have been met.

[0112] Measurement report messages are available on the wireless resources control This is an (RRC) message. The measurement report message may be a message for transferring the measurement results of wireless quality to the network. The measurement report message includes measurement result information (MeasResults). The measurement result information (MeasResults) may include a measurement identifier associated with a static event identifier (event identifier) ​​and the measurement results of the serving cell's wireless quality. The control unit 140 may include the measurement identifier associated with the static event identifier (event identifier) ​​in the measurement report message when it has met the conditions for joining a static event that indicate that the static criteria have been met.

[0113] The control unit 240 of the base station 200 may, based on the measurement report message, choose whether or not to have the UE 100 perform a measurement (hereinafter referred to as a relaxed measurement) according to a measurement relaxation method that relaxes the measurement of radio quality for adjacent cells. In this way, the control unit 240 determines whether or not to perform a relaxed measurement and controls the relaxed measurement.

[0114] If the control unit 240 chooses to have the UE 100 perform a relaxation measurement, it can execute the process in step S104. The control unit 240 can determine that the conditions for joining a static event have been met if the measurement report message contains a measurement identifier associated with a static event identifier (event identifier) ​​and the UE 100 has not performed a relaxation measurement (for example, the control unit 240 has not instructed the UE 100 to perform a relaxation measurement). The control unit 240 may also determine whether the static criteria have been met based on the measurement results included in the measurement report message. For example, the control unit 240 can determine whether the static criteria have been met based on the static threshold sent to the UE 100 and the measurement results.

[0115] When the conditions for joining a static event are met, the control unit 240 may determine that the conditions for performing a relaxation measurement on the UE 100 have been met and may choose to have the UE 100 perform a relaxation measurement. If the control unit 240 chooses to have the UE 100 perform a relaxation measurement, it can perform the following processes.

[0116] Step S104: The wireless communication unit 220 of the base station 200 transmits a relaxation measurement instruction to the UE 100 to cause it to perform a relaxation measurement. The communication unit 120 of the UE 100 receives the relaxation measurement instruction from the serving cell.

[0117] Relaxation measurement instructions may be sent individually to the UE100 via RRC reset messages or the like. Relaxation measurement instructions may include, for example, measurement configuration information (MeasConfig) to cause the UE100 to perform relaxation measurements. Relaxation measurement instructions may also be instructions to enable the execution of relaxation measurements. In addition, relaxation measurement instructions may include parameters for multiplying the allowable time, as described later, by a predetermined number.

[0118] Step S105: The control unit 140 of UE100 performs a relaxation measurement on adjacent cells in accordance with the relaxation measurement instruction. For example, when a relaxation measurement is performed, the allowable time for detecting adjacent cells may be multiplied by a predetermined number, the allowable time for measuring adjacent cells may be multiplied by a predetermined number, and the allowable time for evaluating adjacent cells may be multiplied by a predetermined number.

[0119] Note that adjacent cells are different from the serving cell. Adjacent cells are at least one of the following: intra-frequency cells, inter-NR frequency cells, and inter-RAT frequency cells.

[0120] Step S106: The control unit 140 of UE100 performs measurement and determination in the same manner as in step S102. The control unit 140 may execute the process in step S107 if the conditions for departure from a stationary event are met. Therefore, the control unit 140 may execute the process in step S107 if the stationary criteria are no longer met.

[0121] The control unit 140 may perform the processing in step S107 based on the departure report information (reportOnLeave) included in the event identifier (eventId) indicating a stationary event. The control unit 140 may perform the processing in step S107 if the departure report information (reportOnLeave) indicates that the UE 100 should start the measurement reporting procedure when the departure conditions are met with respect to the serving cell.

[0122] As shown in B3 of Figure 11, if the measurement type information (reportType) is set to the relaxation trigger information (relaxedMeasEventTriggered), and the condition for escaping from the event indicated by the event identifier is met for a serving cell included in the cell trigger list (cellsTriggeredList) defined in the variable measurement report list (VarMeasReportList) for this measurement identifier, the control unit 140 of UE100 may perform the following operations.

[0123] The control unit 140 may delete the serving cell information defined in the variable measurement report list (VarMeasReportList) for this measurement identifier. The control unit 140 may also start the measurement reporting procedure if the departure report information (reportOnLeave) is set to "true" in the corresponding reporting settings. Furthermore, the control unit 140 may delete the measurement report entry in the variable measurement report list (VarMeasReportList) for this measurement identifier if the cell triggered list (cellsTriggeredList) defined in the variable measurement report list (VarMeasReportList) for this measurement identifier is empty. If the periodic reporting timer for this measurement identifier is running, the control unit 140 may stop the reporting timer.

[0124] Step S107: The communication unit 120 of UE100 transmits a measurement report message to the serving cell (base station 200, network), similar to step S103. The wireless communication unit 220 of base station 200 receives the measurement report message.

[0125] The communication unit 120 can send a measurement report message to the serving cell (network) when the static criteria are no longer met. The measurement report message may indicate that the static criteria are no longer met.

[0126] The control unit 140 may include the measurement identifier associated with the static event identifier (event identifier) ​​in the measurement report message when the conditions for departure to a static event are met.

[0127] The control unit 240 of the base station 200 may, similar to step S103, select whether or not to have the UE 100 perform a relaxation measurement based on the measurement report message.

[0128] If the control unit 240 chooses not to have the UE 100 perform a relaxation measurement, it can execute the process in step S108. The control unit 240 can determine that the conditions for exiting to a static event have been met if the measurement report message contains a measurement identifier associated with a static event identifier (event identifier) ​​and the UE 100 is performing a relaxation measurement (for example, if the control unit 240 has instructed the UE 100 to perform a relaxation measurement). The control unit 240 may also determine whether the static criteria have been met based on the measurement results contained in the measurement report message.

[0129] When the condition for departing from a stationary event is met, the control unit 240 may determine that the conditions for performing a relaxation measurement on the UE 100 are no longer met and may choose not to have the UE 100 perform a relaxation measurement. If the control unit 240 chooses not to have the UE 100 perform a relaxation measurement, it can perform the following processes.

[0130] Step S108: The wireless communication unit 220 of the base station 200 transmits a normal measurement instruction to the UE 100 to prevent it from performing a relaxed measurement. The communication unit 120 of the UE 100 receives the normal measurement instruction from the serving cell.

[0131] Normal measurement instructions may be sent individually to the UE100 via RRC reset messages, etc. Normal measurement instructions may include, for example, measurement configuration information (MeasConfig) to prevent the UE100 from performing relaxation measurements. Relaxation measurement instructions may also be instructions to disable the execution of relaxation measurements.

[0132] The control unit 140 of UE100 terminates the execution of relaxation measurements for adjacent cells in accordance with the normal measurement instruction. The control unit 140 then starts normal measurements for adjacent cells.

[0133] (2) Second example of operation Referring to Figures 12 to 15, the second operational example will be explained, primarily focusing on the differences from the operational example described above. The second operational example describes a case in which UE100 transmits a UE auxiliary information message to base station 200 depending on whether the static criteria have been met.

[0134] Step S201: As shown in Figure 12, the wireless communication unit 220 of the base station 200 transmits the configuration information to the UE 100, similar to step S101. The communication unit 120 of the UE 100 receives the configuration information from the base station 200 (serving cell).

[0135] In this example, as shown in Figure 13, the configuration information may include status setting information (stationaryStatusConfig) for configuring the UE100 to report auxiliary information to the base station 200 informing it of the stationary state detected by the UE100. This status setting information may include the setting value of the prohibit timer for reporting status information (stationaryStatusProhibitTimer). The prohibit timer (Txxx) starts in response to the transmission of a UE auxiliary information message containing the status information described below. The prohibit timer (Txxx) stops in response to the release of the status setting information (stationaryStatusConfig) or the reception of information to release the status setting information (stationaryStatusConfig).

[0136] Furthermore, the configuration information may include the quiescent threshold T1. The status configuration information (stationaryStatusConfig) may also include the quiescent threshold T1.

[0137] The control unit 140 of UE100 sets the information included in the configuration information. Based on the set information, UE100 can perform the following operations.

[0138] Step S202: The control unit 140 of UE100 performs measurement and determination in the same manner as in step S102. The control unit 140 may determine that UE100 is in a stationary state if the stationary criteria are met. On the other hand, the control unit 140 may determine that UE100 is not in a stationary state if the stationary criteria are not met.

[0139] As shown in Figure 14, the control unit 140 of the UE 100, which has the capability to provide stationary status information indicating whether or not it is in a stationary state in the RRC connected state, may perform the following actions when it enters or leaves a stationary state, provided that it is configured to provide status information. Note that the UE 100 may be configured to provide status information based on status setting information.

[0140] If the control unit 140 has not sent a UE auxiliary information message since receiving the status setting information, it may start sending a UE auxiliary information message. Also, if the last UE auxiliary information message sent to the network contained status information indicating that the UE 100 is not in a quiescent state, the control unit 140 may start sending a UE auxiliary information message in response to the quiescent criteria being met. Also, if the last UE auxiliary information message sent to the network contained status information indicating that the UE 100 is in a quiescent state, the control unit 140 may start sending a UE auxiliary information message in response to the quiescent criteria no longer being met.

[0141] Furthermore, the control unit 140 may start the prohibit timer in response to the transmission of a UE auxiliary information message containing status information. The communication unit 120 does not need to transmit the next UE auxiliary information message containing status information if the prohibit timer is running.

[0142] As shown in Figure 14, the control unit 140 may start the prohibit timer, with its timer value set to the prohibit timer setting value (stationaryStatusProhibitTimer), if (i) it has not sent a UE auxiliary information message containing status information since being configured to provide status information, or (ii) the current stationary state is different from the state indicated by the last UE auxiliary information message containing status information, and the prohibit timer is not running. The control unit 140 may also start sending a UE auxiliary information message to provide status information.

[0143] As shown in Figures 14 and 15, when the control unit 140 starts sending a UE auxiliary information message to provide status information, it includes the status information in the UE auxiliary information message. The status information indicates whether or not the UE 100 is in a stationary state. In this example, the status information indicates that the UE 100 is in a stationary state.

[0144] Step S203: The communication unit 120 of UE100 transmits a UE auxiliary information message to the serving cell (base station 200, network). The communication unit 120 can transmit the UE auxiliary information message to the serving cell (network) when the stationary criteria are met. The radio communication unit 220 of base station 200 receives the UE auxiliary information message.

[0145] UE Auxiliary Information Messages are for radio resources control This is an (RRC) message. The UE supplementary information message may be a message used to show information about UE100 to the network. The UE supplementary information message may indicate that the quiescent criteria have been met by providing status information indicating whether or not UE100 is in a quiescent state.

[0146] The control unit 240 of the base station 200 may choose whether or not to have the UE 100 perform a relaxation measurement based on the UE auxiliary information message. If the control unit 240 chooses to have the UE 100 perform a relaxation measurement, it can execute the process in step S204. The control unit 240 may also choose to have the UE 100 perform a relaxation measurement if the UE auxiliary information message includes status information indicating that the UE 100 is in a stationary state.

[0147] Steps S204 and S205: This is the same as steps S104 and S105.

[0148] Step S206: The control unit 140 of UE100 performs measurement and determination in the same manner as in step S202. Here, we will proceed with the explanation assuming that the control unit 140 has determined that the static criterion is no longer met and that UE100 is not in a static state.

[0149] The control unit 140 may (ii) start sending a UE auxiliary information message if the prohibit timer is not running because the current stationary state is different from the state indicated by the last UE auxiliary information message sent, which includes state information. The control unit 140 includes state information in the UE auxiliary information message indicating that the UE 100 is not in a stationary state.

[0150] Step S207: The communication unit 120 of UE100 transmits a UE auxiliary information message to the serving cell (base station 200, network). The communication unit 120 can transmit a UE auxiliary information message to the serving cell (network) when the static criteria are no longer met. The radio communication unit 220 of base station 200 receives the UE auxiliary information message.

[0151] The control unit 240 of the base station 200 may choose whether or not to have the UE 100 perform a relaxation measurement based on the UE auxiliary information message. If the control unit 240 chooses not to have the UE 100 perform a relaxation measurement, it can execute the process in step S208. The control unit 240 may also choose not to have the UE 100 perform a relaxation measurement if the UE auxiliary information message includes status information indicating that the UE 100 is not in a stationary state.

[0152] Steps S208 and S209: This is the same as steps S108 and S109.

[0153] (3) Third example of operation Referring to Figures 5 to 7 and Figure 16, the third operation example will be explained, primarily focusing on the differences from the operation example described above. The third operation example will explain stationary and non-cell edge events (eventS2). The sequence in this operation example is the same as in the first operation example.

[0154] The event identifier may indicate quiescent and non-cell edge events (eventS2) as described later. As shown in Figure 6, the event identifier (eventId) may include a quiescent threshold T1 applied to the quiescent criterion and a non-cell edge threshold T2 applied to the non-cell edge criterion.

[0155] The non-cell edge threshold T2 may include at least one of a power threshold (s-SearchThresholdP) compared to a value calculated based on the received power measured as radio quality for the serving cell, and a quality threshold (s-SearchThresholdQ) compared to a value calculated based on the received quality measured as radio quality for the serving cell.

[0156] The power threshold (s-SearchThresholdP) is S SearchThresholdP This is acceptable. The network has a power threshold (s-SearchThresholdP) within SIB2. IntraSearchP and S nonIntraSearchP The following values ​​may be set: S IntraSearchPThis specifies the threshold value of Srxlev for measuring cells within frequency. nonIntraSearchP This specifies the Srxlev threshold for measuring NR inter-frequency cells and RAT inter-cells. The quality threshold (s-SearchThresholdQ) is S SearchThresholdQ This is acceptable. The network has a quality threshold (s-SearchThresholdQ) within SIB2. IntraSearchQ and S nonIntraSearchQ The following values ​​may be set: S IntraSearchQ This specifies the threshold value for Squal for measuring cells within the frequency range. nonIntraSearchQ This specifies the threshold values ​​for Squal for measuring NR inter-frequency cells and RAT inter-cells.

[0157] Step S102: The control unit 140 of UE100 performs measurement and determination. Based on the measurement result of the wireless quality and the static threshold T1, the control unit 140 determines whether the static criterion is met. In addition, based on the measurement result of the wireless quality and the non-cell edge threshold T2, the control unit 140 determines whether the non-cell edge criterion is met. The non-cell edge criterion is a criterion used to select whether or not to perform measurement according to a measurement relaxation method that relaxes the measurement of wireless quality for adjacent cells, and is a criterion for determining whether or not UE100 is in a non-cell edge state, not at the cell edge of the serving cell. As a method for determining whether or not the non-cell edge criterion is met, the control unit 140 may determine whether or not the following formula is met. Srxlev > S SearchThresholdP and Squal > S SearchThresholdQ

[0158] S SearchThresholdQ If not set, Squal > S SearchThresholdQ This does not need to be determined. In other words, the control unit 140 determines Srxlev > S SearchThresholdP You may determine whether the condition is met.

[0159] As shown in B1 of Figure 16, the control unit 140 may consider that the conditions for joining stationary and non-cell end events have been met if condition S2-1 is met. Condition S2-1 is that (i) UE100 has been at least a predetermined period (T) after handover to the serving cell or after (re)establishment of the RRC connection to the serving cell. SearchDeltaP_stationary (ii) Having performed a normal measurement of radio quality for cells within a frequency, a normal measurement of radio quality for cells between NR frequencies, or a normal measurement of radio quality for cells between RAT frequencies, (ii) for a specified period (T SearchDeltaP_stationary ), the static criterion is met, and (iii) the non-cell edge criterion is met.

[0160] As shown in B2 of Figure 16, the control unit 140 may consider that the conditions for quiescence and departure from non-cell edge events have been met when condition S2-2 is met. Condition S2-2 is that, after the joining condition is met, (i) a predetermined period (T SearchDeltaP_stationary ), the static criterion is no longer met, or (ii) the non-cell edge criterion is no longer met.

[0161] As shown in B3 of Figure 16, the control unit 140 may target serving cells corresponding to NR measurement targets (MeasObjectNR) associated with stationary and non-cell edge events for this measurement.

[0162] Step S103: The communication unit 120 can send a measurement report message to the serving cell (network) when both the static criterion and the non-cell edge criterion are met.

[0163] The measurement report message includes measurement result information (MeasResults). The measurement result information (MeasResults) may include measurement identifiers associated with static and non-cell edge event identifiers (event identifiers) and measurement results of the serving cell's radio quality. The control unit 140 may include the measurement identifier associated with the static event identifier (event identifier) ​​in the measurement report message if the subscription conditions for static and non-cell edge events are met. The measurement report message may indicate, by measurement identifier, that both the static criterion and the non-cell edge criterion have been met.

[0164] The control unit 240 of the base station 200 can determine that the conditions for joining static and non-cell edge events have been met if the measurement report message includes a measurement identifier associated with a static and non-cell edge event identifier (event identifier), and the UE 100 has not performed a relaxed measurement (for example, the UE 100 has not been instructed to perform a relaxed measurement). The control unit 240 may also determine whether both the static criterion and the non-cell edge criterion have been met based on the measurement results included in the measurement report message. For example, the control unit 240 can determine whether both the static criterion and the non-cell edge criterion have been met based on the static threshold T1 and non-cell edge threshold T2 transmitted to the UE 100 and the measurement results.

[0165] When the conditions for joining stationary and non-cell edge events are met, the control unit 240 may determine that the conditions for performing a relaxation measurement on the UE 100 have been met and may choose to have the UE 100 perform a relaxation measurement. If the control unit 240 chooses to have the UE 100 perform a relaxation measurement, it can execute the process in step S104.

[0166] Step S104: The wireless communication unit 220 of the base station 200 transmits a relaxation measurement instruction to the UE 100 to cause it to perform a relaxation measurement. The communication unit 120 of the UE 100 receives the relaxation measurement instruction from the serving cell.

[0167] A relaxed measurement instruction may, for example, be an instruction to further relax the measurement than in the first example. A relaxed measurement instruction may, for example, have a higher parameter multiplier for multiplying the allowable time by a predetermined amount than in the first example. A relaxed measurement instruction may also be an instruction to allow the non-performance of measurements for adjacent cells.

[0168] Step S105: The control unit 140 of UE100 performs relaxation measurements on adjacent cells in accordance with the relaxation measurement instruction.

[0169] Step S106: The control unit 140 of UE100 performs measurement and determination in the same manner as in step S102. The control unit 140 may execute the process in step S107 if the conditions for stationary and departure from non-cell edge events are met. Therefore, the control unit 140 may execute the process in step S107 if at least one of the stationary criterion and the non-cell edge criterion is no longer met.

[0170] The control unit 140 may perform the processing in step S107 based on the departure report information (reportOnLeave) included in the event identifier (eventId) indicating stationary and non-cell edge events. The control unit 140 may perform the processing in step S107 if the departure report information (reportOnLeave) indicates that the UE 100 should start the measurement reporting procedure when the departure conditions are met with respect to the serving cell.

[0171] Step S107: The communication unit 120 of UE100 transmits a measurement report message to the serving cell (base station 200, network), similar to step S103. The wireless communication unit 220 of base station 200 receives the measurement report message.

[0172] The communication unit 120 can send a measurement report message to the serving cell (network) in response to the fact that at least one of the static criterion and the non-cell edge criterion is no longer met. The measurement report message may indicate that at least one of the static criterion and the non-cell edge criterion is no longer met.

[0173] The control unit 140 may include the measurement identifier associated with the identifier of the stationary and non-cell edge event (event identifier) ​​in the measurement report message when the conditions for departure to stationary and non-cell edge events are met.

[0174] The control unit 240 of the base station 200 may, similar to step S103, select whether or not to have the UE 100 perform a relaxation measurement based on the measurement report message.

[0175] If the control unit 240 chooses not to have the UE 100 perform a relaxation measurement, it can execute the process in step S108. The control unit 240 can determine that the conditions for departure to a stationary and non-cell edge event have been met if the measurement report message includes a measurement identifier associated with the identifiers (event identifiers) of stationary and non-cell edge events, and the UE 100 is performing a relaxation measurement (for example, if the control unit 240 has instructed the UE 100 to perform a relaxation measurement). The control unit 240 may also determine, based on the measurement results included in the measurement report message, whether at least one of the stationary criterion and the non-cell edge criterion is no longer met.

[0176] When the condition for departing from a stationary event is met, the control unit 240 may determine that the conditions for performing a relaxation measurement on the UE 100 are no longer met and may choose not to have the UE 100 perform a relaxation measurement. If the control unit 240 chooses not to have the UE 100 perform a relaxation measurement, it can perform the following processes.

[0177] Step S108: This is the same as step S108 in the first example of operation.

[0178] (4) Fourth example of operation Referring to Figures 12 and 17 through 19, the third operational example will be explained, primarily focusing on the differences from the operational examples described above. The fourth operational example describes a case in which UE100 transmits a UE auxiliary information message to base station 200 depending on whether both the static criterion and the non-cell edge criterion are met, or whether both the static criterion and the non-cell edge criterion are met. The sequence in this operational example is the same as in the second operational example.

[0179] Step S201: As shown in Figure 12, the wireless communication unit 220 of the base station 200 transmits the configuration information to the UE 100, similar to step S101. The communication unit 120 of the UE 100 receives the configuration information from the base station 200 (serving cell).

[0180] In this example, as shown in Figure 13, the configuration information may include status configuration information (stationaryAndNot-at-cell-edgeStatusConfig) for configuring UE100 to report auxiliary information to base station 200 informing it of the stationary state and non-cell edge state detected by UE100. The status configuration information may include the setting value of the prohibit timer for reporting status information (stationaryAndNot-at-cell-edgeStatusProhibitTimer). The prohibit timer (Tyyy) starts in response to the transmission of a UE auxiliary information message containing the status information described below. The prohibit timer (Tyyy) stops in response to the release of the status configuration information (stationaryAndNot-at-cell-edgeStatusConfig) or the reception of information to release the status configuration information (stationaryAndNot-at-cell-edgeStatusConfig).

[0181] Furthermore, the configuration information may include the stationary threshold T1 and the non-cell edge threshold T2. The status configuration information (stationaryAndNot-at-cell-edgeStatusConfig) may include the stationary threshold T1 and the non-cell edge threshold T2.

[0182] The control unit 140 of UE100 sets the information included in the configuration information. Based on the set information, UE100 can perform the following operations.

[0183] Step S202: The control unit 140 of UE100 performs measurement and determination in the same manner as in step S102. The control unit 140 may determine that UE100 is in a stationary state if the stationary criterion is met. On the other hand, the control unit 140 may determine that UE100 is not in a stationary state if the stationary criterion is not met. Furthermore, the control unit 140 may determine that UE100 is in a non-cell edge state if the non-cell edge criterion is met. On the other hand, the control unit 140 may determine that UE100 is not in a non-cell edge state if the non-cell edge criterion is not met.

[0184] As shown in Figure 18, the control unit 140 of the UE 100, which has the capability to provide status information indicating whether or not it is in a stationary state and whether or not it is in a non-cell-edge state in the RRC connected state, may perform the following actions when it enters or leaves the stationary state if it is configured to provide status information. Note that the UE 100 may be configured to provide status information based on status setting information.

[0185] If the control unit 140 has not sent a UE auxiliary information message since receiving the status setting information, it may start sending a UE auxiliary information message. Also, if the last UE auxiliary information message sent to the network contained status information indicating that the UE 100 is not in a quiescent state or not in a non-cell edge state, the control unit 140 may start sending a UE auxiliary information message in response to both the quiescent criterion and the non-cell edge criterion being met. Also, if the last UE auxiliary information message sent to the network contained status information indicating that the UE 100 is in a quiescent state and also in a non-cell edge state, the control unit 140 may start sending a UE auxiliary information message in response to at least one of the quiescent criterion and the non-cell edge criterion no longer being met.

[0186] Furthermore, the control unit 140 may start the prohibit timer in response to the transmission of a UE auxiliary information message containing status information. The communication unit 120 does not need to transmit the next UE auxiliary information message containing status information if the prohibit timer is running.

[0187] As shown in Figure 18, the control unit 140 may start the prohibit timer, setting the timer value to the prohibited timer setting value (StationaryAndNot-at-cell-edgeStatusProhibitTimer), if (i) it has not sent a UE auxiliary information message containing status information since it was set to provide status information, or (ii) the current stationary state or non-cell edge state is different from the state indicated by the last UE auxiliary information message containing status information sent, and the prohibit timer is not running. The control unit 140 may also start sending a UE auxiliary information message to provide status information.

[0188] As shown in Figures 18 and 19, when the control unit 140 starts sending a UE auxiliary information message to provide status information, it includes the status information in the UE auxiliary information message. The status information indicates that UE 100 is in a stationary state and is not at a cell edge state, or that UE 100 is not in a stationary state or is not at a cell edge state. Alternatively, the status information may indicate that UE 100 is no longer in a stationary state and is not at a cell edge state, or that UE 100 is in at least one of the states of not being in a stationary state and not being at a cell edge state.

[0189] Step S203: The communication unit 120 of UE100 transmits a UE auxiliary information message to the serving cell (base station 200, network). The communication unit 120 can transmit the UE auxiliary information message to the serving cell (network) depending on whether both the stationary criterion and the non-cell edge criterion are met. The radio communication unit 220 of base station 200 receives the UE auxiliary information message.

[0190] The UE auxiliary information message may indicate, based on the status information, that both the quiescent criterion and the non-cell edge criterion have been met.

[0191] The control unit 240 of the base station 200 may choose whether or not to have the UE 100 perform a relaxation measurement based on the UE auxiliary information message. If the control unit 240 chooses to have the UE 100 perform a relaxation measurement, it can execute the process in step S204. The control unit 240 may also choose to have the UE 100 perform a relaxation measurement if the UE auxiliary information message includes status information indicating that the UE 100 is in a stationary state and is in a non-cell end state.

[0192] Steps S204 and S205: This is the same as steps S104 and S105.

[0193] Step S206: The control unit 140 of UE100 performs measurement and determination in the same manner as in step S202. Here, we will proceed with the assumption that the control unit 140 has determined that at least one of the static criterion and the non-cell edge criterion is no longer met.

[0194] The control unit 140 may (ii) start sending a UE auxiliary information message if the current stationary state or non-cell end state is different from the state indicated by the last transmitted UE auxiliary information message which includes state information, and the prohibit timer is not running. The control unit 140 includes state information in the UE auxiliary information message indicating that the UE 100 is not in a stationary state or a non-cell end state.

[0195] Step S207: The communication unit 120 of UE100 transmits a UE auxiliary information message to the serving cell (base station 200, network). The communication unit 120 can transmit a UE auxiliary information message to the serving cell (network) when at least one of the stationary criteria and the non-cell edge criteria is no longer met. The radio communication unit 220 of base station 200 receives the UE auxiliary information message.

[0196] The control unit 240 of the base station 200 may choose whether or not to have the UE 100 perform a relaxation measurement based on the UE auxiliary information message. If the control unit 240 chooses not to have the UE 100 perform a relaxation measurement, it can execute the process in step S208. The control unit 240 may also choose not to have the UE 100 perform a relaxation measurement if the UE auxiliary information message includes status information indicating that the UE 100 is not in a stationary state or not in a non-cell end state.

[0197] Steps S208 and S209: This is the same as steps S108 and S109.

[0198] (5) Fifth example of action Referring to Figures 20 to 22, the fifth operation example will be explained, primarily focusing on the differences from the operation examples described above. In the fifth operation example, UE100 chooses to perform measurements on adjacent cells according to the measurement relaxation method, depending on whether the static criteria are met.

[0199] Steps S301 and S302: This is the same as steps S101 and S102 or S201 and S202.

[0200] The control unit 140 may determine whether or not to select to perform relaxation measurements by the following method.

[0201] As shown in Figure 21, the control unit 140 has setting information (lowMobilityEvaluation) for selecting to perform relaxation measurements based on a low mobility criterion set in UE100, and setting information (cellEdgeEvaluation) for selecting to perform relaxation measurements based on a non-cell edge criterion set in UE100, and the power threshold (S) included in the static threshold T1 SearchDeltaP_stationary ) and period information (T SearchDeltaP_stationary If ) and are set to UE100, you may choose to perform radio quality measurements for in-frequency cells according to the measurement relaxation method if the following conditions are met.

[0202] The above conditions (i) at least for a specified period (T SearchDeltaP_stationary (ii) having performed normal radio quality measurements for cells within a frequency, normal radio quality measurements for cells between NR frequencies, or normal radio quality measurements for cells between RATs, and (ii) for a specified period (T SearchDeltaP_stationary ), the static criterion may be met.

[0203] The control unit 140 determines the wireless quality of the serving cell to be "Srxlev > S nonIntraSearchP " and "Squal > S nonIntraSearchQ If the above condition is met, the control unit 140 may choose not to perform a radio quality measurement on an inter-frequency cell or inter-RAT cell for which one hour has not elapsed since the radio quality measurement. The control unit 140 may choose not to perform a radio quality measurement on an inter-frequency cell or inter-RAT cell if relaxation measurement on a high-priority frequency is permitted, i.e., if highPriorityMeasRelax is set to "true".

[0204] The control unit 140 determines the wireless quality of the serving cell to be "Srxlev > S nonIntraSearchP " and "Squal > S nonIntraSearchQ If the above condition is not met, you may choose to perform radio quality measurements for inter-frequency cells or inter-RAT cells according to the same or different relaxation measurements as described above.

[0205] Furthermore, as shown in Figure 22, when both setting information for selecting to perform relaxation measurements based on a low mobility criterion (lowMobilityEvaluation) and setting information for selecting to perform relaxation measurements based on a non-cell edge criterion (cellEdgeEvaluation) are set in the UE100, the control unit 140 sets the power threshold (S) included in the static threshold T1. SearchDeltaP_stationary ) and period information (T SearchDeltaP_stationaryIf ) and are set to UE100, you may choose not to perform a wireless quality measurement on an intra-frequency cell, inter-frequency cell, or inter-RAT cell that has not been measured for more than one hour since the wireless quality measurement, provided the following conditions are met.

[0206] The above conditions (i) at least for a specified period (T SearchDeltaP_stationary (ii) Having performed a normal measurement of radio quality for cells within a frequency, a normal measurement of radio quality for cells between NR frequencies, or a normal measurement of radio quality for cells between RATs, (ii) for a specified period (T SearchDeltaP_stationary (iii) the static criterion is met, and (iii) the non-cell edge criterion is met.

[0207] The control unit 140 (i) for at least a predetermined period (T SearchDeltaP_stationary ), if a normal measurement of radio quality for an intra-frequency cell, a normal measurement of radio quality for an NR inter-frequency cell, or a normal measurement of radio quality for an RAT inter-cell is performed, and (ii) the non-cell end criterion is met, and (iii) relaxation measurements at high priority frequencies are not permitted, then the radio quality measurement for a low priority intra-frequency cell, a low priority inter-frequency cell, or a low priority RAT inter-cell may be performed in accordance with the same or different relaxation measurements as described above.

[0208] The control unit 140 determines the wireless quality of the serving cell as follows: "Srxlev ≤ S nonIntraSearchP " or "Squal ≤ S nonIntraSearchQ If the above condition is met, the radio quality measurement for high-priority inter-frequency cells or high-priority inter-RAT cells may be selected to be performed according to the same or different relaxation measurements as described above.

[0209] Steps S303 and S306: The same applies as in steps S103 or S203 and S106 or S206. After making a selection, UE100 may, for example, perform the selected operation in accordance with the instructions from base station 200 if it receives instructions from base station 200.

[0210] Steps S304, S305, S307: This is the same as step S104 or S204, step S106 or S206, and step S104 or S204.

[0211] (Other embodiments) In the above-described embodiment, UE100 may be a specific UE100B. Since a specific UE100B is assumed to be stationary compared to a general UE100A, it is easier to satisfy the stationary criterion.

[0212] In the above-described embodiment, UE100 may perform the above-described operation only when it is in the RRC Connected state. Alternatively, UE100 may perform any of the first to fifth operation examples when it is in the RRC Connected state, and may perform any of the first to fifth operation examples when it is in the RRC Idle state or RRC Inactive state.

[0213] In the embodiments described above, the base station 200 may choose to have the UE 100 perform a relaxation measurement or not perform a measurement for a predetermined adjacent cell (non-performance of measurement) in accordance with the conditions described in the fifth example of operation. The base station 200 may transmit an instruction to the UE 100 based on the selection result. The UE 100 may choose to perform a relaxation measurement or not perform a measurement based on the instruction from the base station 200.

[0214] In the embodiments described above, UE100 may use a different message (for example, a new RRC message) instead of the measurement report message and the UE auxiliary information message.

[0215] In the embodiments described above, the base station 200 may include a plurality of units. The plurality of units may include a first unit that hosts the higher layer included in the protocol stack, and a second unit that hosts the lower layer included in the protocol stack. The higher layer may include the RRC layer, SDAP layer, and PDCP layer, and the lower layer may include the RLC layer, MAC layer, and PHY layer. The first unit may be a CU (central unit), and the second unit may be a DU (Distributed Unit). The plurality of units may include a third unit that performs processing below the PHY layer. The second unit may perform processing above the PHY layer. The third unit may be a RU (Radio Unit). The base station 200 may be one of the plurality of units and may be connected to other units of the plurality of units. The base station 200 may also be an IAB (Integrated Access and Backhaul) donor or IAB node.

[0216] In the embodiments described above, a mobile communication system based on NR was used as an example for the mobile communication system 1. However, the mobile communication system 1 is not limited to this example. The mobile communication system 1 may be a system compliant with LTE or another generation system of the 3GPP standard (e.g., 6th generation). The base station 200 may be an eNB that provides E-UTRA user plane and control plane protocol termination directed to UE100 in LTE. The mobile communication system 1 may be a system compliant with a TS of a standard other than the 3GPP standard.

[0217] The steps in the operation of the above-described embodiment do not necessarily have to be executed chronologically in the order shown in the flowchart or sequence diagram. For example, the steps in the operation may be executed in a different order than that shown in the flowchart or sequence diagram, or they may be executed in parallel. Also, some steps in the operation may be deleted, or further steps may be added to the process. Furthermore, each of the above-described operation flows can be implemented not only separately and independently, but also by combining two or more operation flows. For example, some steps of one operation flow may be added to another operation flow, or some steps of one operation flow may be replaced with some steps of another operation flow.

[0218] A program may be provided that causes a computer to execute each process performed by the UE100 or base station 200. The program may be recorded on a computer-readable medium. Using a computer-readable medium, it is possible to install the program on a computer. Here, the computer-readable medium on which the program is recorded may be a non-transient recording medium. The non-transient recording medium is not particularly limited, but may be a recording medium such as a CD-ROM or DVD-ROM. Alternatively, the circuits that execute each process performed by the UE100 or base station 200 may be integrated, and at least a part of the UE100 or base station 200 may be configured as a semiconductor integrated circuit (chipset, SoC).

[0219] In the above embodiments, "transmit" may mean performing processing on at least one layer within the protocol stack used for transmission, or may mean physically transmitting a signal wirelessly or via a wire. Alternatively, "transmit" may mean a combination of performing the processing on the at least one layer and physically transmitting a signal wirelessly or via a wire. Similarly, "receive" may mean performing processing on at least one layer within the protocol stack used for reception, or may mean physically receiving a signal wirelessly or via a wire. Alternatively, "receive" may mean a combination of performing the processing on the at least one layer and physically receiving a signal wirelessly or via a wire.

[0220] As described above, the embodiments have been explained in detail with reference to the drawings. However, the specific configuration is not limited to the above, and various design changes and the like can be made without departing from the gist.

Explanation of Reference Numerals

[0221] 1: Mobile communication system 10: Network 120: Communication unit 121: Receiver 122: Transmitter 140: Control unit 200: Base station 220: Wireless communication unit 230: Network communication unit 240: Control unit 300: Core network device

Claims

1. A receiving unit (121) receives from a base station (200) first information relating to a static criterion and information for specifying the period over which fluctuations in the received level value applied to the static criterion are evaluated. The system includes a control unit (140) that receives second information regarding non-cell edge criteria from the base station, and performs a relaxation measurement when the stationary criteria and the non-cell edge criteria are met and the base station receives third information instructing it to perform a relaxation measurement, If the control unit has not received the third information from the base station, it determines whether the static criterion is met during the period in which the fluctuation of the received level value applied to the static criterion is evaluated, and based on that determination, it selects to perform the relaxation measurement. The control unit, If no information is set to specify a threshold for the reception quality value applied to the non-cell edge criterion, it is determined whether the non-cell edge criterion is met based on the threshold for the reception level value applied to the non-cell edge criterion. If information is set to specify a threshold value for the reception quality value that applies to the non-cell edge criterion, then it is determined whether the non-cell edge criterion is met based on the threshold value for the reception level value that applies to the non-cell edge criterion and the threshold value for the reception quality value that applies to the non-cell edge criterion. Communication device (100).

2. The threshold value of the received level that is applied to the non-cell edge criterion is included in the second information. The communication device according to claim 1.

3. The receiving unit receives a system information block from the base station that includes the first information, information for specifying the period over which the fluctuation of the received level value is evaluated, and the second information. The communication device according to claim 1 or 2.

4. The first information indicates a first value as a threshold value for the received level value applied to the stationary criterion, The control unit determines whether the static criterion is met based on the reference signal received power (RSRP) of the serving cell and the first value. The communication device according to claim 1 or 2.

5. The second piece of information indicates a second value as a threshold value for the received level value applied to the non-cell edge criterion, The control unit determines, based on the second value, whether the non-cell edge criterion is met. The communication device according to claim 4.

6. If the second information further indicates a third value as a threshold for the received quality value applied to the non-cell edge criterion, the control unit determines whether the non-cell edge criterion is met based on the second value, the reference signal received quality (RSRQ) of the serving cell, and the third value. The communication device according to claim 5.

7. The control unit selects at least one of the following measurements as the relaxation measurement: a measurement on an intra-frequency cell and a measurement on an inter-frequency cell. The communication device according to claim 1 or 2.

8. The aforementioned communication device is a Red Cap (Reduced Capability) user device. The communication device according to claim 1 or 2.

9. A transmitting unit that transmits to a communication device (100) first information relating to a static criterion and information for specifying a period during which fluctuations in the received level value applied to the static criterion are evaluated. The system includes a control unit that controls the communication device to perform the relaxation measurement when the stationary criterion and the non-cell edge criterion are met, by transmitting a second piece of information regarding the non-cell edge criterion to the communication device and a third piece of information instructing the communication device to perform the relaxation measurement, The control unit, If the third information has not been transmitted to the communication device, the system will determine whether the static criterion is met during the period in which the fluctuation of the received level value applied to the static criterion is evaluated, and will control the communication device to select the execution of the relaxation measurement based on that determination. If information for specifying a threshold value for the reception quality value applied to the non-cell edge criterion is not set in the communication device, the communication device is controlled to determine whether the non-cell edge criterion is met based on the threshold value for the reception level value applied to the non-cell edge criterion. If information for specifying the threshold value of the reception quality applied to the non-cell edge criterion is set in the communication device, the communication device will be controlled to determine whether the non-cell edge criterion is met based on the threshold value of the reception level applied to the non-cell edge criterion and the threshold value of the reception quality applied to the non-cell edge criterion. Base station (200).

10. The threshold value of the received level that is applied to the non-cell edge criterion is included in the second information. The base station according to claim 9.

11. The transmitting unit transmits a system information block to the communication device, which includes the first information, information for specifying the period during which the fluctuation of the received level value is evaluated, and the second information. The base station according to claim 9 or 10.

12. In the communication device, at least one of the measurements of an intra-frequency cell and an inter-frequency cell is performed as the relaxation measurement. The base station according to claim 9 or 10.

13. The aforementioned communication device is a Red Cap (Reduced Capability) user device. The base station according to claim 9 or 10.

14. A communication method performed by a communication device (100), The steps include receiving from a base station (200) first information relating to a static criterion and information specifying a period for which fluctuations in the received level value applied to the static criterion are evaluated, The steps include: receiving second information regarding non-cell edge criteria from the base station, and performing the relaxation measurement when the stationary criteria and the non-cell edge criteria are met and receiving third information from the base station instructing to perform the relaxation measurement; If the third information has not been received from the base station, the steps include determining whether the static criterion is met during the period in which the fluctuation of the received level value applied to the static criterion is evaluated, and selecting to perform the relaxation measurement based on that determination, If no information is set to specify a threshold for the reception quality value applied to the non-cell edge criterion, the step of determining whether the non-cell edge criterion is met based on a threshold for the reception level value applied to the non-cell edge criterion, If information for specifying a threshold value for the reception quality value applied to the non-cell edge criterion is set, the procedure includes the step of determining whether the non-cell edge criterion is met based on the threshold value for the reception level value applied to the non-cell edge criterion and the threshold value for the reception quality value applied to the non-cell edge criterion. Communication method.

15. A communication method performed at a base station (200), The steps include transmitting to a communication device (100) first information relating to a static criterion and information specifying a period for which fluctuations in the received level value applied to the static criterion are evaluated, The method includes the step of controlling the communication device to perform the relaxation measurement when the stationary criterion and the non-cell edge criterion are met, by transmitting a second piece of information relating to a non-cell edge criterion to the communication device and a third piece of information instructing the communication device to perform the relaxation measurement, If the third information has not been transmitted to the communication device, the steps include determining whether the static criterion is met during the period in which the fluctuation of the received level value applied to the static criterion is evaluated, and controlling the communication device to select to perform the relaxation measurement based on that determination, If information for specifying a threshold value for reception quality applied to the non-cell edge criterion has not been set in the communication device, the communication device is controlled to determine whether the non-cell edge criterion is met based on a threshold value for reception level applied to the non-cell edge criterion. If information for specifying a threshold value for the reception quality value applied to the non-cell edge criterion is set in the communication device, the communication device is controlled to determine whether the non-cell edge criterion is met based on the threshold value for the reception level value applied to the non-cell edge criterion and the threshold value for the reception quality value applied to the non-cell edge criterion. Communication method.

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