Patent Description:
A radio access scheme and a radio network for cellular mobile communications (which will hereinafter be referred to as "Long Term Evolution (LTE; trade name)" or "Evolved Universal Terrestrial Radio Access (EUTRA)") and a core network (which will be referred to as "Evolved Packet Core or EPC") have been studied by the 3rd Generation Partnership Project (3GPP).

As a radio access scheme and a radio network technology for a 5th-generation cellular system, technical studies and standardization of LTE-Advanced Pro, which is an enhanced technology of LTE, and New Radio technology (NR), which is a new radio access technology, have been conducted by the 3GPP (NPL <NUM>). <NUM> Generation Core Network (5GC), which is a core network for a 5th generation cellular system, has also been studied (NPL <NUM>).

Document <NPL>, discusses the configuration and reconfiguration of the SDAP entity, proposing that the SDAP configuration of each PDU session should contain the parameters mapping relationship between QoS flows and DRBs; default DRB ID; associated PDU session ID; SDAP header presence configuration of DRBs; and proposing that the SDAP entity of UE will release the stored UL QoS flow to DRB mapping rule under the control of network e.g. in case of QoS flow release.

Document <NPL>, discusses procedures regarding QoS message flows.

Document <NPL>, discusses QoS flow remapping with/without mobility.

Document <NPL>, proposes inter alia that the RAN may configure, modify and release a configured `Uplink QoS Flow to DRB' mapping by RRCConnectionReconfiguration.

As one of NR technical studies, protocols for a radio access layer are studied which perform Quality of Service (QoS) management between higher layers than the Internet Protocol (IP) layer and a radio access layer of NR.

However, there is a problem in that the management of QoS cannot be performed correctly, and communication between a base station apparatus and a terminal apparatus cannot be efficiently performed in a case that necessary information is not transmitted and/or received between the higher layers and the radio access layer.

In view of the circumstances described above, an object of an aspect of the present invention is to provide a terminal apparatus capable of efficiently communicating with a base station apparatus, and a method used for the terminal apparatus.

In order to accomplish the object described above, there is provided a terminal apparatus and a method as defined in the claims, respectively.

According to an aspect of the present invention, a terminal apparatus can correctly perform QoS management and can communicate efficiently.

Embodiments of the present invention will be described below in detail with reference to the drawings.

LTE (and LTE-A Pro) and NR may be defined as different RATs. NR may be defined as a technology included in LTE. LTE may be defined as a technology included in NR. LTE capable of connecting with NR through Dual connectivity may be distinguished from conventional LTE. The present embodiment may be applied to NR, LTE and other RATs. Terms associated with LTE and NR are used in the following description. However, the present invention may be applied to other technologies using other terms.

<FIG> is a schematic diagram of a communication system.

E-UTRA <NUM> is a radio access technology described in NPL <NUM> or the like, and is constituted by Cell Groups (CGs) configured in one or multiple frequency bands. An E-UTRAN Node B (eNB) <NUM> is a base station apparatus of E-UTRA. An Evolved Packet Core (EPC) <NUM> is a core network described in NPL <NUM> or the like and is designed as a core network for E-UTRA. An interface <NUM> is an interface between the eNB <NUM> and the EPC <NUM>, where there is a Control Plane (CP) through which control signals transfer and a User Plane (UP) through which user data transfers.

NR <NUM> is a new radio access technology that is currently being studied by the 3GPP and includes Cell Groups (CGs) that are configured in one or multiple frequency bands. A gNode B (gNB) <NUM> is an NR base station apparatus. A 5GC <NUM> is a new core network for NR which is currently being studied by 3GPP, and is described in NPL <NUM> and the like.

An interface <NUM> is an interface between the eNB <NUM> and the 5GC <NUM>, an interface <NUM> is an interface between the gNB <NUM> and the 5GC <NUM>, an interface <NUM> is an interface between the gNB <NUM> and the EPC <NUM>, an interface <NUM> is an interface between the eNB <NUM> and the gNB <NUM>, and an interface <NUM> is an interface between the EPC <NUM> and 5GC <NUM>. The interface <NUM>, the interface <NUM>, the interface <NUM>, the interface <NUM>, and the interface <NUM> are interfaces that transfer the CP only, or the UP only, or both the CP and the UP, and details are being discussed by 3GPP. The interface <NUM>, the interface <NUM>, the interface <NUM>, the interface <NUM>, and the interface <NUM> may not exist depending on communication systems provided by network operators.

A UE <NUM> is a terminal apparatus supporting NR or supporting both E-UTRA and NR.

<FIG> is a diagram of Protocol Stacks of the UP and the CP of the terminal apparatus and the base station apparatus in the E-UTRA radio access layer.

<FIG> is a diagram of a protocol stack of the UP used in a case that the UE <NUM> communicates with the eNB <NUM>.

A Physical layer (PHY) <NUM> is a radio physical layer for providing transmission services to higher layers by using Physical Channels. The PHY <NUM> is connected with a Medium Access Control layer (MAC) <NUM>, which is a higher layer described below, via Transport Channels. Data is exchanged between the MAC <NUM> and the PHY <NUM> via the transport channels. The data is transmitted and/or received via radio physical channels between the PHYs of the UE <NUM> and the eNB <NUM>.

The MAC <NUM> maps various Logical Channels to various transport channels. The MAC <NUM> is connected with a Radio Link Control layer (RLC) <NUM>, which is a higher layer described below, via logical channels. The logical channels are roughly classified depending on types of information transmitted, specifically, classified into control channels transmitting control information and traffic channels transmitting user information. The MAC <NUM> has a function of controlling the PHY <NUM> in order to perform Discontinuous Reception and Transmission (DRX and DTX), a function of performing Random Access procedures, a function of reporting transmit power information, a function of performing HARQ control, and the like (NPL <NUM>).

An RLC <NUM> divides (Segmentation) data received from a Packet Data Convergence Protocol Layer (PDCP) <NUM>, which is a higher layer described below, and adjusts the data size such that lower layers can properly transmit data. The RLC <NUM> also has a function of ensuring Quality of Service (QoS) required for each piece of data. In other words, the RLC <NUM> has a function of data retransmission control or the like (NPL <NUM>).

The PDCP <NUM> may have a header compression function for compressing unnecessary control information in order to efficiently transmit IP Packets, which are user data, in radio segments. The PDCP <NUM> may also have a data encryption function (NPL <NUM>).

Note that data processed in the MAC <NUM>, the RLC <NUM>, and the PDCP <NUM> is referred to as MAC Protocol Data Units (PDUs), RLC PDUs, and PDCP PDUs, respectively. Data transferred from a higher layer to the MAC <NUM>, the RLC <NUM>, and the PDCP <NUM>, or data to be transferred to a higher layer is referred to as MAC Service Data Units (SDUs), RLC SDUs, and PDCP SDUs, respectively.

<FIG> is a diagram of a protocol stack of the CP used in a case that the UE <NUM> communicates with the eNB <NUM>.

In addition to the PHY <NUM>, the MAC <NUM>, the RLC <NUM>, and the PDCP <NUM>, there is a Radio Resource Control layer (RRC) <NUM> in the protocol stack of the CP. The RRC <NUM> performs configuration or reconfiguration of Radio Bearers (RBs) to control logical channels, transport channels, and physical channels. The RBs may be classified into Signaling Radio Bearers (SRBs) and Data Radio Bearers (DRBs), and the SRBs may be used as paths for transmitting RRC messages, which are control information. The DRBs may be used as paths for transmitting user data. Each RB may be configured in the RRCs <NUM> of the eNB <NUM> and the UE <NUM> (NPL <NUM>).

The functional classification of the MAC <NUM>, the RLC <NUM>, the PDCP <NUM>, and the RRC <NUM> described above is an example, and some or all of the respective functions may not be implemented. Some or all of the functions of each layer may be included in another layer.

<FIG> is a diagram of Protocol Stacks of the UP and CP of the terminal apparatus and the base station apparatus in the NR radio access layer.

<FIG> is a diagram of a protocol stack of the UP used in a case that the UE <NUM> communicates with the gNB <NUM>.

A Physical layer (PHY) <NUM> is a radio physical layer of NR and may provide transmission services to higher layers by using Physical Channels. The PHY <NUM> may be connected with a Medium Access Control layer (MAC) <NUM>, which is a higher layer described below, via Transport Channels. Data may be exchanged between the MAC <NUM> and the PHY <NUM> via the transport channels. The data may be transmitted and/or received between the PHYs of the UE <NUM> and the gNB <NUM> via radio physical channels. Unlike the radio physical layer PHY <NUM> of E-UTRA, details of the PHY <NUM> are under discussion by 3GPP.

The MAC <NUM> may map various Logical Channels to various transport channels. The MAC <NUM> may be connected with a Radio Link Control layer (RLC) <NUM>, which is a higher layer described below, via logical channels. The logical channels are roughly classified depending on types of information transmitted, and may be classified into control channels transmitting control information and traffic channels transmitting user information. The MAC <NUM> may have a function of controlling the PHY <NUM> in order to perform Discontinuous Reception and Transmission (DRX and DTX), a function of performing Random Access procedures, a function of reporting transmit power information, a function of performing HARQ control, and the like (NPL <NUM>). Unlike the MAC <NUM> of E-UTRA, details of the MAC <NUM> are under discussion by 3GPP.

The RLC <NUM> may divide (Segmentation) data received from a Packet Data Convergence Protocol Layer (PDCP) <NUM>, which is a higher layer described below, and adjust the data size such that lower layers can properly transmit data. The RLC <NUM> may also have a function of ensuring Quality of Service (QoS) required for each piece of data. In other words, the RLC <NUM> may have a function of data retransmission control or the like (NPL <NUM>). Unlike the RLC <NUM> of E-UTRA, details of the RLC <NUM> are under discussion by 3GPP.

A PDCP <NUM> may have a header compression function for compressing unnecessary control information in order to efficiently transmit IP Packets, which are user data, in radio segments. The PDCP <NUM> may also have a data encryption function (NPL <NUM>). Unlike the PDCP <NUM> of E-UTRA, details of the PDCP <NUM> are under discussion by 3GPP.

A Service Data Adaptation Protocol (SDAP) <NUM> performs mapping of QoS flows and DRBs of downlink transmitted from a core network to a terminal apparatus via a base station apparatus, and mapping of QoS information flows and DRBs of uplink transmitted from a terminal apparatus to a core network via a base station apparatus, and may have a function for storing mapping rule information (NPL <NUM>). QoS flows include one or more Service Data Flows (SDFs) that are processed by the same QoS policy (NPL <NUM>). The SDAP <NUM> may have a function of Reflective QoS for performing mapping of QoS flows and DRBs of uplink, based on information of downlink QoS flows (NPL <NUM> and NPL <NUM>). Details are under discussion by 3GPP.

Note that the IP layer, and the Transmission Control Protocol (TCP) layer, the User Datagram Protocol (UDP) layer, the application layer, and the like, which are higher than the IP layer, are higher layers of the SDAP (not illustrated). For the SDAP of a terminal apparatus, a layer for performing association between service data flows and QoS flows is also a higher layer of the SDAP.

Note that data processed in the MAC <NUM>, the RLC <NUM>, the PDCP <NUM>, and the SDAP <NUM> may be referred to as MAC Protocol Data Units (PDUs), RLC PDUs, PDCP PDUs, and SDAP PDUs, respectively. Data transferred from a higher layer to the MAC <NUM>, the RLC <NUM>, and the PDCP <NUM>, or data to be transferred to a higher layer may be referred to as MAC Service Data Units (SDUs), RLC SDUs, PDCP SDUs, and SDAP SDUs, respectively.

<FIG> is a diagram of a protocol stack of the CP used in a case that the UE <NUM> communicates with the gNB <NUM>.

In addition to the PHY <NUM>, the MAC <NUM>, the RLC <NUM>, and the PDCP <NUM>, there is a Radio Resource Control layer (RRC) <NUM> in the protocol stack of the CP. The RRC <NUM> may perform configuration or reconfiguration of Radio Bearers (RBs) to control logical channels, transport channels, and physical channels. The RBs may be classified into Signaling Radio Bearers (SRBs) and Data Radio Bearers (DRBs), and the SRBs may be used as paths for transmitting RRC messages, which are control information. The DRBs may be used as paths for transmitting user data. Each RB may be configured in the RRCs <NUM> of the gNB <NUM> and the UE <NUM> (NPL <NUM>).

The functional classification of the MAC <NUM>, the RLC <NUM>, the PDCP <NUM>, the SDAP <NUM>, and the RRC <NUM> described above is an example, and some or all of the respective functions may not be implemented. Some or all of the functions of each layer may be included in another layer.

Note that, in embodiments of the present invention, the MAC <NUM>, the RLC <NUM>, the PDCP <NUM>, and the RRC <NUM> may be referred to as the MAC for E-UTRA or the MAC for LTE, the RLC for E-UTRA or the RLC for LTE, the PDCP for E-UTRA or the PDCP for LTE, and the RRC for E-UTRA or the RRC for LTE, respectively, to distinguish protocols of E-UTRA and NR hereinbelow. The MAC <NUM>, the RLC <NUM>, the PDCP <NUM>, and the RRC <NUM> may also be referred to as the MAC for NR, the RLC for NR, the RLC for NR, and the RRC for NR, respectively.

As also illustrated in <FIG>, the eNB <NUM>, the gNB <NUM>, the EPC <NUM>, and the 5GC <NUM> may be connected to one another via the interface <NUM>, the interface <NUM>, the interface <NUM>, the interface <NUM>, and the interface <NUM>. Thus, the RRC <NUM> in <FIG> may be replaced with the RRC <NUM> in <FIG> to support various communication systems. The PDCP <NUM> in <FIG> may also be replaced with the PDCP <NUM> in <FIG>. The RRC <NUM> in <FIG> may include functions of the RRC <NUM> in <FIG>. The PDCP <NUM> in <FIG> may be the PDCP <NUM> in <FIG>.

Embodiment <NUM> will be described with reference to <FIG> and <FIG> to <FIG>.

<FIG> is a diagram illustrating an example of a flow of an RRC reconfiguration procedure according to each embodiment of the present invention.

The RRC Reconfiguration procedure includes procedures used for handover and Mesurement and the like, in addition to establishment, change, and release of RBs, and change, release, and the like of secondary cells in NR as disclosed in NPL <NUM>. According to each embodiment, procedures used for establishment, change, and release of RBs, addition, change, and release of cell groups, handover and Mesurement, and the like in NR may be referred to as RRC reconfiguration procedures, or may have another designation. The procedures used for establishment, change, and release of RBs, addition, change, and release of cell groups, handover and Mesurement, and the like according to each embodiment may be procedures in E-UTRA according to NPL <NUM>, or may be referred to as RRC connection reconfiguration procedures.

In an RRC reconfiguration procedure, the UE <NUM> receives an RRC reconfiguration message (RRCReconfigration) from the gNB <NUM> (step S400), and performs various configurations according to information included in the RRC reconfiguration message, such as configuration of DRBs (step S402). After step S402, the UE <NUM> may transmit an RRC reconfiguration complete message (RRCReconfigrationComplete) and the like to the gNB <NUM> (not illustrated).

<FIG> is a block diagram illustrating a configuration of a terminal apparatus (UE <NUM>). Note that <FIG> illustrates only main components closely related in order to avoid complicated explanation.

The UE <NUM> illustrated in <FIG> includes a receiver <NUM> configured to receive RRC reconfiguration messages from the gNB <NUM>, a storage unit <NUM> configured to store mapping rules between QoS flows and DRBs, and a processing unit <NUM> configured to process messages and data.

<FIG> is an example of information related to DRB configuration involved in SDAP configuration, and Abstract Syntax Notation One (ASN. <NUM>) description of information, among the information included in the RRC reconfiguration message in <FIG>. The specifications related to RRC (NPL <NUM> and NPL <NUM>) in the 3GPP describe messages, information (Information Element or IE), and the like related to RRC by using ASN. In the example of ASN. <NUM> of <FIG>, <omitted> or <partly omitted> indicates that not part of the description of ASN. <NUM>, but other pieces of information are omitted. Note that there may also be omitted information in parts where neither <omitted> nor <partly omitted> is indicated. Note that the example of ASN. <NUM> in <FIG> does not exactly follow the description method of ASN. <NUM>, but is a description of an example of parameters of SDAP configuration according to the claimed embodiment, and other names or other descriptions may be used. The example of ASN. <NUM> in <FIG> only illustrates examples about main information closely related to the present invention in order to avoid complicated explanation.

The information represented by DRB-ToAddModList in <FIG> is a list of pieces of information indicating configuration of DRBs to be added or modified, each represented by DRBToAddMod. The information represented by pduSession-Identity in DRB-ToAddMod (information indicating configuration of a DRB to be added or modified) may be information identifying a PDU session described in NPL <NUM>. The information identifying a PDU session may be a PDU session identifier described in NPL <NUM> or may be other information. In the example of <FIG>, the information identifying a PDU session is an integer value from <NUM> to <NUM>, but may take another value. The information identifying a PDU session may be used to identify a PDU session associated with a DRB to be configured. In <FIG>, the information identifying a PDU session is included in information indicating configuration of a DRB to be added or modified, but may be described elsewhere. The information represented by DRB-Identity in the information indicating configuration of a DRB to be added or modified is a DRB identity of a DRB to be added or modified. In the example of <FIG>, the information represented by a DRB-Identity is an integer value from <NUM> to <NUM>, but may take another value. The DRB identity may be used to uniquely identify a DRB in a PDU session.

In <FIG>, the information represented by sdap-Config in the information indicating configuration of a DRB to be added or modified is information related to SDAP entity configuration. The information represented by qosFlowIdAddList in the information related to SDAP entity configuration is list information of QoS flow identifiers (each represented by QoSFlow-Identity) corresponding (mapping) to a DRB identity. The QoS flow identifiers corresponding (mapping) to a DRB correspond (map) to the DRB in the uplink direction. A QoS flow identifier may be an integer value. The information represented by qosFlowIdReleaseList in the information related to SDAP entity configuration is list information of QoS flow identifiers (each represented by QoSFlow-Identity) to be released from among QoS flow identifiers corresponding (mapping) to a DRB identity.

The information represented by sdapHeader-UL may be information indicating that an SDAP header for uplink is present in SDAP PDUs in the uplink direction corresponding (mapping) to a DRB to be configured. The information indicating that an SDAP header for uplink is present may be translated in that an SDAP header for uplink is necessary in SDAP PDUs or SDAP SDUs in the uplink direction corresponding (mapping) to a DRB to be configured. The information represented by sdapHeader-DL may be information indicating that an SDAP header for downlink is present in SDAP PDUs in the downlink direction corresponding (mapping) to a DRB to be configured. The information indicating that an SDAP header for uplink is present, and the information indicating that an SDAP header for uplink is present may indicate that it is present by using true, enable, or the like, or may indicate that it is present with a numerical value representing a header length.

The information represented by reflective may be information indicating that a DRB to be configured correspond (mapping) to reflective QoS flows described in NPL <NUM> and NPL <NUM>. The information indicating that DRBs to be configured correspond (mapping) to reflective QoS flows may indicate that a DRB to be configured correspond (mapping) to reflective QoS flows by using true, enable, or the like. Note that in each embodiment, a QoS flow may include one or more Service Data Flows (SDFs) that are processed by the same QoS policy (NPL <NUM>). Note that a reflective QoS flow may indicate a QoS flow in which a Reflective QoS Indicator (RQI) for being handled as a reflective QoS is included in an encapsulated header (N3 header) of user data of a core network of each packet of one or more SDFs among SDFs assigned to QoS flows.

The information indicated by default may be information indicating that DRB to be added or modified are a default DRB. The default DRB may be DRB corresponding to QoS flows with a default QoS policy, or may be a DRB mapped in a case that mapping rules between QoS flows and a DRB corresponding to uplink SDAP SDUs are not stored. The information indicating that a DRB to be added or modified are a default DRB may indicate that a DRB to be added or modified is a default DRB by using true, enable, and the like.

The information indicated by DRB-ToReleaseList may be information indicating a list of DRB identities of DRBs to be released.

Some or all of the information illustrated in <FIG> may be optional. In other words, the information illustrated in <FIG> is included in an RRC reconfiguration message as necessary. Different processing may be defined as processing of the UE <NUM> in cases that the information is included or not included in an RRC reconfiguration message. For example, the information indicating that an SDAP header for uplink is present, the information indicating that an SDAP header for downlink is present, the information indicating that a DRB to be configured correspond (mapping) to reflective QoS flows, the information indicating that a DRB to be added or modified is a default DRB, and the like may be optional.

The information illustrated in <FIG> may include information having dependencies. For example, in a case that the number of QoS flow identifiers included in list information of QoS flow identifiers (QoSFlow-Identity) corresponding (mapping) to DRB identities is two or more, or the number of QoS flows corresponding (mapping) to one DRB is two or more, it may mean that information is present which indicates that an SDAP header for uplink is present. Even in a case that the number of QoS flows corresponding (or mapping) to one DRB is two or more, it may mean that a case of default DRBs is excluded, that is, an SDAP header for uplink is not present. Conversely, it may mean that, in a case of default DRBs, an SDAP header for uplink is present.

For example, in a case that information indicating that a DRB to be configured correspond (mapping) to reflective QoS flows is included in an RRC reconfiguration message, it may mean that information is present which indicates that an SDAP header for downlink is present.

Note that the information indicating that an SDAP header for downlink is present may be information indicating that a DRB to be configured correspond (mapping) to reflective QoS flows. In other words, in a case that the information indicating that an SDAP header for downlink is present in an RRC reconfiguration message, it may indicate that an SDAP header for downlink is present, and a DRB to be configured correspond (mapping) to reflective QoS flows.

<FIG> illustrates an example of a processing method of the processing unit <NUM> of the UE <NUM> in <FIG>, according to Embodiment <NUM>.

<FIG> illustrates an example of an SDAP header for uplink according to Embodiment <NUM>.

Next, an example of a DRB configuration procedure including SDAP configuration in an RRC reconfiguration procedure will be described with reference to <FIG>, according to the claimed embodiments.

The receiver <NUM> of the UE <NUM> receives an RRC reconfiguration message from the gNB <NUM> (step S400). The processing unit <NUM> of the UE <NUM> performs configuration in accordance with information included in the RRC reconfiguration message (step S402). The RRC reconfiguration message in Embodiment <NUM> includes information indicating that an SDAP header for uplink is present in information related to SDAP entity configuration. In a case that DRB identities and list information of QoS flow identifiers corresponding (mapping) to DRB identities are included in the RRC reconfiguration message, the processing unit <NUM> of the UE <NUM> creates mapping rules between QoS flows corresponding to the QoS flow identifiers for uplink and DRBs having the DRB identities to store in the storage unit <NUM>. At this time, the processing unit <NUM> of the UE <NUM> may notify higher layers of information of storing, together with the QoS flow identifiers. Since the RRC reconfiguration message includes list information of QoS flow identifiers to be released, the processing unit <NUM> of the UE <NUM> releases mapping rules between QoS flows for uplink and DRBs stored in the storage unit <NUM>, corresponding (mapping) to QoS flow identifiers included in the list information of the QoS flow identifiers to be released. At this time, the processing unit <NUM> of the UE <NUM> may notify higher layers of information of releasing, together with the QoS flow identifiers. Since the RRC reconfiguration message includes list information of DRB identities to be released, the processing unit <NUM> of the UE <NUM> releases mapping rules between QoS flows for uplink and DRBs stored in the storage unit <NUM>, corresponding (mapping) to DRB identities included in the list information of the DRB identities to be released. At this time, the processing unit <NUM> of the UE <NUM> may notify higher layers of information of releasing, together with the QoS flow identifiers.

Next, the processing unit <NUM> of the UE <NUM> receives an SDAP SDU and a QoS Flow Identifier (QFI) of a QoS flow corresponding (mapping) to the SDAP SDU from a higher layer (step S700).

Next, the processing unit <NUM> of the UE <NUM> checks whether or not the DRB mapped to the SDAP SDU received from the higher layer is a DRB configured such that an SDAP header for uplink is present, and in a case that the DRB is configured such that an SDAP header for uplink is present, creates an SDAP header for uplink (step S702).

<FIG> are examples of formats of an SDAP header for uplink according to Embodiment <NUM>. <FIG> both include a QFI field and R fields (R bits). The R field (R bits) is a reserved field (reserved bits). In <FIG>, there is one <NUM>-bit length R field, whereas there is one <NUM>-bit length QFI field. In <FIG>, there are two <NUM>-bit length R fields (or one <NUM>-bit length R field), while there is one <NUM>-bit length QFI field. Note that the format of an SDAP header for uplink is not always as this format, but, for example, instead of the R field, there may be a reflective indicator field (RQI field). There may also be other fields or bits, for example, fields or bits indicating that there are no mapping rules between QoS flows and DRBs corresponding to SDAP PDUs received from a higher layer.

Next, the processing unit <NUM> of the UE <NUM> configures the QFI of the QoS flow corresponding to the SDAP PDU received from the higher layer in step S700, to the QFI field of the SDAP header for uplink. The processing unit <NUM> of the UE <NUM> may set zero ('<NUM>') to the reserved field of the SDAP header for uplink (step S704). Note that in a case that an RQI field is present in the SDAP header for uplink, the processing unit <NUM> of the UE <NUM> may set zero ('<NUM>') to the RQI field.

Next, the processing unit <NUM> of the UE <NUM> adds the SDAP header for uplink generated in step S702 and step S704 to the SDAP SDU received from the higher layer in step S700 to create an SDAP PDU, and submits the SDAP PDU to a lower layer according to mapping rules between QoS flows and DRBs stored in the storage unit <NUM>. Note that the order of storing values to each field of an SDAP header for uplink from step S700 to step S706 and adding an SDAP header for uplink to an SDAP SDU may not be this order. Note that in a case that the SDAP header for uplink is not configured to be present in step S702, an SDAP header for uplink may not be created, and the SDAP SDU received from the higher layer may be submitted as is, as an SDAP PDU to a lower layer.

As described above, in Embodiment <NUM>, the terminal apparatus can perform efficient communication by transmitting and/or receiving necessary information such as QoS flow identifier information between higher layers and radio access layer to correctly managing QoS.

Embodiment <NUM> will be described with reference to <FIG> and <FIG> to <FIG>, and <FIG>. <FIG> are the same as in Embodiment <NUM>.

In other words, <FIG> is a diagram illustrating an example of a flow of an RRC reconfiguration procedure according to each embodiment.

<FIG> is a block diagram illustrating a configuration of a terminal apparatus (UE <NUM>) according to each embodiment. Note that <FIG> illustrates only main components closely related to the present invention in order to avoid complicated explanation.

<FIG> is an example of information related to DRB configuration involved in SDAP configuration, and Abstract Syntax Notation One (ASN. <NUM>) description of information, among the information included in the RRC reconfiguration message in <FIG>. The specifications related to RRC (NPL <NUM> and NPL <NUM>) in the 3GPP describe messages, information (Information Element or IE), and the like related to RRC by using ASN. In the example of ASN. <NUM> of <FIG>, <omitted> or <partly omitted> indicates that not part of the description of ASN. <NUM>, but other pieces of information are omitted. Note that there may also be omitted information in parts where neither <omitted> nor <partly omitted> is indicated. Note that the example of ASN. <NUM> in <FIG> does not exactly follow the description method of ASN. <NUM>, but is a description of an example of parameters of SDAP configuration, and other names or other descriptions may be used. The example of ASN. <NUM> in <FIG> only illustrates examples about main information closely related to the claimed embodiment in order to avoid complicated explanation.

The information represented by sdapHeader-UL may be information indicating that an SDAP header for uplink is present in SDAP PDUs in the uplink direction corresponding (mapping) to DRB to be configured. The information indicating that an SDAP header for uplink is present may be translated in that an SDAP header for uplink is necessary in SDAP PDUs or SDAP SDUs in the uplink direction corresponding (mapping) to DRB to be configured. The information represented by sdapHeader-DL may be information indicating that an SDAP header for downlink is present in SDAP PDUs in the downlink direction corresponding (mapping) to DRB to be configured. The information indicating that an SDAP header for uplink is present, and the information indicating that an SDAP header for uplink is present may indicate that it is present by using true, enable, or the like, or may indicate that it is present with a numerical value representing a header length.

The information represented by reflective may be information indicating that DRB to be configured correspond (mapping) to reflective QoS flows described in NPL <NUM> and NPL <NUM>. The information indicating that DRB to be configured correspond (mapping) to reflective QoS flows may indicate that DRB to be configured correspond (mapping) to reflective QoS flows by using true, enable, or the like. Note that in each embodiment, a QoS flow may include one or more Service Data Flows (SDFs) that are processed by the same QoS policy (NPL <NUM>). Note that a reflective QoS flow may indicate a QoS flow in which a Reflective QoS Indicator (RQI) for being handled as a reflective QoS is included in an encapsulated header (N3 header) of user data of a core network of each packet of one or more SDFs among SDFs assigned to QoS flows.

The information indicated by default may be information indicating that DRB to be added or modified are default DRB. The default DRB may be DRB corresponding (mapping) to QoS flows with a default QoS policy, or may be DRB mapped in a case that mapping rules between QoS flows and DRB corresponding to uplink SDAP SDUs are not stored. The information indicating that DRB to be added or modified are default DRB may indicate that DRB to be added or modified are default DRB by using true, enable, and the like.

Some or all of the information illustrated in <FIG> may be optional. In other words, the information illustrated in <FIG> is included in an RRC reconfiguration message as necessary. Different processing may be defined as processing of the UE <NUM> in cases that the information is included or not included in an RRC reconfiguration message. For example, the information indicating that an SDAP header for uplink is present, the information indicating that an SDAP header for downlink is present, the information indicating that DRB to be configured correspond (mapping) to reflective QoS flows, the information indicating that DRB to be added or modified are default DRB, and the like may be optional.

The information illustrated in <FIG> may include information having dependencies. For example, in a case that the number of QoS flow identifiers included in list information of QoS flow identifiers (QoSFlow-Identity) corresponding (mapping) to DRB identities is two or more, or the number of QoS flows corresponding (mapping) to one DRB is two or more, it may mean that information is present which indicates that an SDAP header for uplink is present. Even in a case that the number of QoS flows corresponding (or mapping) to one DRB is two or more, it may mean that a case of default DRB is excluded, that is, an SDAP header for uplink is not present. Conversely, it may mean that, in a case of default DRB, an SDAP header for uplink is present.

For example, in a case that information indicating that DRB to be configured correspond (mapping) to reflective QoS flows is included in an RRC reconfiguration message, it may mean that information is present which indicates that an SDAP header for downlink is present.

Note that the information indicating that an SDAP header for downlink is present may be information indicating that DRB to be configured correspond (mapping) to reflective QoS flows. In other words, in a case that the information indicating that an SDAP header for downlink is present in an RRC reconfiguration message, it may indicate that an SDAP header for downlink is present, and DRB to be configured correspond (mapping) to reflective QoS flows.

Next, an example of a DRB configuration procedure including SDAP configuration in an RRC reconfiguration procedure according to Embodiment <NUM> will be described with reference to <FIG> and <FIG>.

The receiver <NUM> of the UE <NUM> receives an RRC reconfiguration message from the gNB <NUM> (step S400). The processing unit <NUM> of the UE <NUM> performs configuration in accordance with information included in the RRC reconfiguration message (step S402). The RRC reconfiguration message in Embodiment <NUM> includes information indicating corresponding (mapping) to reflective QoS flows, information indicating that an SDAP header for downlink is present, or information indicating corresponding (mapping) to reflective QoS flows and information indicating that an SDAP header for downlink is present, in the information related to SDAP entity configuration. In a case that DRB identities and list information of QoS flow identifiers corresponding (mapping) to DRB identities are included in the RRC reconfiguration message, the processing unit <NUM> of the UE <NUM> creates mapping rules between QoS flows corresponding to the QoS flow identifiers for uplink and DRBs having the DRB identities to store in the storage unit <NUM>. At this time, the processing unit <NUM> of the UE <NUM> may notify higher layers of information of storing, together with the QoS flow identifiers. Since the RRC reconfiguration message includes list information of QoS flow identifiers to be released, the processing unit <NUM> of the UE <NUM> releases mapping rules between QoS flows for uplink and DRBs stored in the storage unit <NUM>, corresponding (mapping) to QoS flow identifiers included in the list information of the QoS flow identifiers to be released. At this time, the processing unit <NUM> of the UE <NUM> may notify higher layers of information of releasing, together with the QoS flow identifiers. Since the RRC reconfiguration message includes list information of DRB identities to be released, the processing unit <NUM> of the UE <NUM> releases mapping rules between QoS flows for uplink and DRBs stored in the storage unit <NUM>, corresponding (mapping) to DRB identities included in the list information of the DRB identities to be released. At this time, the processing unit <NUM> of the UE <NUM> may notify higher layers of information of releasing, together with the QoS flow identifiers.

Next, the processing unit <NUM> of the UE <NUM> receives a downlink SDAP PDU from a lower layer (step S900).

Next, the processing unit <NUM> of the UE <NUM> checks whether or not the DRB that receives the downlink SDAP PDU is configured such that an SDAP header for downlink is present, and in a case that the DRB is configured such that an SDAP header for downlink is present, processes the SDAP header for downlink of the received downlink SDAP PDU (step S902).

Next, the processing unit <NUM> of the UE <NUM> checks whether the field of the RQI of the SDAP header for downlink is a value ('<NUM>') indicating that the reflective QoS indication is action (step S904). In a case that the RQI field is a value ('<NUM>') indicating reflective QoS indication non-action, the processing unit <NUM> of the UE <NUM> removes the SDAP header for downlink from the downlink SDAP PDU received from the lower layer in step S900 to create an SDAP SDU and transfer the SDAP SDU to a higher layer (step S906).

In a case that the field of the RQI of the SDAP header for downlink is <NUM> in step S902, the processing unit <NUM> of the UE <NUM> further checks whether or not a mapping rule between a QoS flow for uplink and a DRB corresponding to a value of a QFI included in an SDAP header for downlink is stored in the storage unit <NUM> (step S908). In a case that the mapping rule is stored in the storage unit <NUM>, the processing unit <NUM> of the UE <NUM> removes the header for downlink from the SDAP PDU received from the lower layer in step S900 to create an SDAP SDU, and transfers the value of the QFI included in the SDAP header for downlink and information indicating reflective indication action (RQI= <NUM>) to a higher layer along with the SDAP SDU (step S912). Here, by transferring the value of the QFI included in the SDAP header for downlink to the higher layer along with the SDAP SDU, it may also serve to transfer information of a reflective indication.

In a case that a mapping rule between a QoS flow for uplink and a DRB corresponding to a value of a QFI included in an SDAP header for downlink are not stored in the storage unit <NUM> in step S908, the processing unit <NUM> of the UE <NUM> stores a mapping rule between a QoS flow for uplink and a DRB corresponding to the value of the QFI included in the SDAP header for downlink in the storage unit <NUM> (step S910), and removes the header for downlink from the SDAP PDU for downlink received from the lower layer in step S900 to create an SDAP SDU, and transfers the value of the QFI included in the SDAP header for downlink and the information of reflective indication to a higher layer along with the SDAP SDU (step S912). Here, by transferring the value of the QFI included in the SDAP header for downlink to the higher layer along with the SDAP SDU, it may also serve to transfer information of a reflective indication.

Note that, from step S900 to step S912, the order of removing an SDAP header for downlink from an SDAP PDU to generate an SDAP SDU, the order for analyzing a field of a downlink SDAP header, and the order of storing a mapping rule between a QoS flow for uplink and a DRB corresponding to a value of a QFI included in an SDAP header for downlink in the storage unit <NUM> may not as those illustrated. Note that in a case that an SDAP header for downlink is not configured to be present in step S902, the processing unit <NUM> of the UE <NUM> may pass the SDAP PDU for downlink received from the lower layer as is, as an SDAP SDU to a higher layer.

Note that, instead of checking whether or not a mapping rule between a QoS flow for uplink and a DRB corresponding to a value of a QFI included in the SDAP header for downlink is stored in the storage unit <NUM> in step S908, the processing unit <NUM> of the UE <NUM> may check whether or not a mapping rule between a QoS flow for uplink and a DRB corresponding to a value of a QFI included in the SDAP header stored in the storage unit <NUM> is active. At this time, in a case that a mapping rule between a QoS flow for uplink and a DRB corresponding to a value of a QFI included in the SDAP header for downlink stored in the storage unit <NUM> is not active, then, instead of storing a mapping rule for a QoS flow for uplink and a DRB corresponding to a value of a QFI included in the SDAP header for downlink in the storage unit <NUM>, the processing unit <NUM> of the UE <NUM> may activate a mapping rule between a QoS flow for uplink and a DRB corresponding to a value of a QFI included in the SDAP header for downlink stored in the storage unit <NUM> in step S910.

As described above, in Embodiment <NUM> of the present invention, the terminal apparatus can perform efficient communication by transmitting and/or receiving necessary information such as QoS flow identifier information and reflective QoS indication information between higher layers and radio access layer to correctly managing QoS.

Embodiment <NUM> will be described with reference to <FIG>, <FIG>, <FIG>, and <FIG> to <FIG>. <FIG> and <FIG> are the same as in Embodiment <NUM> and Embodiment <NUM>.

The information indicated by default may be information indicating that DRBs to be added or modified are default DRB. The default DRB may be DRB corresponding (mapping) to QoS flows with a default QoS policy, or may be DRB mapped in a case that mapping rules between QoS flows and DRB corresponding (mapping) to uplink SDAP SDUs are not stored. The information indicating that DRB to be added or modified are default DRB may indicate that DRB to be added or modified are default DRB by using true, enable, and the like.

<FIG> is a block diagram illustrating a configuration of a terminal apparatus (UE <NUM>) according to Embodiment <NUM>. Note that <FIG> illustrates only main components closely related in order to avoid complicated explanation.

The UE <NUM> illustrated in <FIG> includes a receiver <NUM> configured to receive an RRC reconfiguration message from the gNB <NUM>, and a processing unit <NUM> configured to perform processing in accordance with the RRC reconfiguration request.

Next, a first example of a DRB configuration procedure in an RRC reconfiguration procedure according to Embodiment <NUM> will described with reference to <FIG>, <FIG>, <FIG>, and <FIG>.

The receiver <NUM> of the UE <NUM> receives an RRC reconfiguration message from the gNB <NUM> (step S400). The processing unit <NUM> of the UE <NUM> performs configuration in accordance with information included in the RRC reconfiguration request (step S402).

<FIG> illustrates a first example of a processing method of the processing unit <NUM> of the UE <NUM>, according to Embodiment <NUM> of the present invention. The processing unit <NUM> of the UE <NUM> checks a case that information related to SDAP entity configuration is included in information indicating configuration of a DRB including a DRB identity that is not in part of the current configuration of the UE <NUM>, in a list of information indicating configuration of a DRB to be added or modified, included in the RRC reconfiguration message received from the receiver <NUM>, and whether or not information identifying a PDU session such as a PDU session identifier associated with the SDAP entity configuration is present in part of the current configuration of the UE <NUM> configuration (step S1000). In a case that the information identifying the PDU session is not in part of the current configuration of the UE <NUM> configuration, after establishing an SDAP entity and performing DRB configuration according to the information indicating the configuration of the DRB to be added or modified, the processing unit <NUM> of the UE <NUM> notifies a higher layer of QoS flow identifiers or a list of QoS flow identifiers corresponding (mapping) to the established DRB, and DRB establishment information (step S1002). At this time, the processing unit <NUM> of the UE <NUM> may notify the information identifying the PDU session together. In a case that the information identifying the PDU session is in part of the current configuration of the UE <NUM> configuration, after reconfiguring the SDAP entity and performing DRB configuration according to the information indicating the configuration of the DRB to be added or modified, the processing unit <NUM> of the UE <NUM> notifies a higher layer of QoS flow identifiers or a list of QoS flow identifiers corresponding (mapping) to established DRB, and DRB establishment information (step S1004). At this time, the processing unit <NUM> of the UE <NUM> may notify the information identifying the PDU session together.

Next, a second example of a DRB configuration procedure in an RRC reconfiguration procedure according to Embodiment <NUM> will be described with reference to <FIG> and <FIG>.

<FIG> illustrates a second example of a processing method of the processing unit <NUM> of the UE <NUM>, according to Embodiment <NUM>. The processing unit <NUM> of the UE <NUM> checks that the RRC reconfiguration message received from the receiver <NUM> includes information related to a list of QoS flow identifiers to be released (step S1100). At this time, the RRC reconfiguration message may include DRB identities corresponding (mapping) to the QoS flow identifiers to be released. Next, the processing unit <NUM> of the UE <NUM> notifies a higher layer of the released QoS flow identifiers included in the list of the QoS flow identifiers released and information of releasing (step S1104). At this time, the processing unit <NUM> of the UE <NUM> may notify information identifying PDU sessions corresponding each of the released QoS flow identifiers together.

Next, a third example of a DRB configuration procedure in an RRC reconfiguration procedure according to Embodiment <NUM> will be described with reference to <FIG> and <FIG>.

<FIG> illustrates a third example of a processing method of the processing unit <NUM> of the UE <NUM>, according to Embodiment <NUM>. The processing unit <NUM> of the UE <NUM> checks that the RRC reconfiguration message includes a list of DRB identities to be released (step S1200). Next, the processing unit <NUM> of the UE <NUM> reconfigures the SDAP entity in a case that the DRB identities to be released are DRB identities associated with the SDAP entity, and notifies a higher layer of the QoS flow identifiers corresponding (mapping) to DRBs having the DRB identities to be released, or the list of the QoS identifiers, and the information of releasing (step S1202). At this time, the processing unit <NUM> of the UE <NUM> may notify information identifying PDU sessions corresponding each of the released QoS flow identifiers together. Note that in a case that the DRB identities to be released are not associated with the SDAP entity and are DRB identities associated with EPS bearer identifiers, the EPS bearer identifiers may be notified to a higher layer.

As described above, in Embodiment <NUM>, the terminal apparatus can perform efficient communication by transmitting and/or receiving information of QoS flow identifiers corresponding (mapping) to DRBs between higher layers and the radio access layer to correctly managing QoS.

Note that the DRB configuration according to each embodiment of the present invention may be included in an RRC Establishment procedure or an RRC ReEstablishment procedure, in addition to an RRC reconfiguration procedure.

A program running on an apparatus according to the present invention may serve as a program that controls a Central Processing Unit (CPU) and the like to cause a computer to operate in such a manner as to realize the functions of the above-described embodiments according to the present invention. Programs or the information handled by the programs are temporarily read into a volatile memory, such as a Random Access Memory (RAM) while being processed, or stored in a non-volatile memory, such as a flash memory, or a Hard Disk Drive (HDD), and then read by the CPU to be modified or rewritten, as necessary.

Note that the apparatuses in the above-described embodiments may be partially enabled by a computer. In such a case, a program for realizing such control functions may be recorded on a computer-readable recording medium to cause a computer system to read the program recorded on the recording medium to perform the program. It is assumed that the "computer system" mentioned here refers to a computer system built into the apparatuses, and the computer system includes an operating system and hardware components such as a peripheral device. The "computer-readable recording medium" may be any of a semiconductor recording medium, an optical recording medium, a magnetic recording medium, and the like.

Moreover, the "computer-readable recording medium" may include a medium that dynamically retains a program for a short period of time, such as a communication line that is used to transmit the program over a network such as the Internet or over a communication line such as a telephone line, and may also include a medium that retains a program for a fixed period of time, such as a volatile memory within the computer system for functioning as a server or a client in such a case. The above-described program may be configured to realize some of the functions described above, and additionally may be configured to realize the functions described above, in combination with a program already recorded in the computer system.

Claim 1:
A terminal apparatus (<NUM>) for communicating with a base station apparatus (<NUM>), the terminal apparatus (<NUM>) comprising:
a receiver (<NUM>) configured to receive, from the base station apparatus (<NUM>), a Radio Resource Control, RRC, reconfiguration message including a Data Radio Bearer, DRB, configuration and a first DRB identity of a first DRB to be released, the DRB configuration including a Service Data Adaptation Protocol, SOAP, configuration, and a second DRB identity of a second DRB to be added, which are associated with each other;
a storage unit (<NUM>) configured to store Quality of Service, QoS, flow to DRB mapping rules based on the DRB configuration; and
a processing unit (<NUM>) configured to release all of a plurality of the QoS flow to DRB mapping rules corresponding to the first DRB indicated by the first DRB identity, based on the RRC reconfiguration message, wherein
the first DRB identity is associated with an SDAP entity.