GB2634008A

GB2634008A - Apparatus and method for use of logical channel identifier indices

Info

Publication number: GB2634008A
Application number: GB2306467.8A
Authority: GB
Inventors: Henttonen Tero; Heikki Turtinen Samuli; Hathiramani Navin
Original assignee: Nokia Technologies Oy
Current assignee: Nokia Technologies Oy
Priority date: 2023-05-02
Filing date: 2023-05-02
Publication date: 2025-04-02
Also published as: GB202306467D0; CN121176080A; WO2024227577A1

Abstract

Disclosed is an apparatus, comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to: determine that at least one Logical Channel Identification (LCID) index is to be used to transfer information to support communication within a communication network; determine the information and an encoding configuration to allow the information be encoded within a field of the at least one LCID index; and encode the information for transmission in a message including the at least one LCID field in accordance with the encoding configuration. The information may comprise additional, extra, or further information not typically encoded within a field of a Logical Channel Identifier index. The information may comprise information to support communication within a communication network as part of a random access procedure. The information may comprise dynamic user equipment assistance information to support communication within a communication network. The message in which the at least one LCID field is included may comprise a Common Control Channel (CCCH) message. The information may comprise information to support communication of UE capability information between network nodes as part of initial establishment of a communication link.

Description

APPARATUS AND METHOD FOR USE OF LOGICAL CHANNEL IDENTIFIER INDICES

TECHNOLOGICAL FIELD

Various example embodiments relate to communication technologies, and more particularly, to apparatus and methods for facilitating use of a finite resource, in particular, the logical channel identifier (LCID).

BACKGROUND

In 5G New Radio, different kinds of data transfer services are offered by the media access control (MAC) layer. To support those different kinds of data transfer services, multiple types of logical channels are defined.

A media access control (MAC) protocol data unit (PDU) may contain one or more MAC control elements (CEs) corresponding to one or more features requiring the MAC CEs.

According to the third generation partnership project (3GPP) technical specification (TS) 38.321 V16.4.0, the MAC PDU also contains a subheader which includes a logical channel identification (LCID) value or an extended LCID (eLCID) value. The LCID value or eLCID value may identify the logical channel instance or the type of corresponding MAC CE as described in the Tables 6.2.1-1, 6.2.1-1b, 6.2.1-2 and 6.2.1-2b in 3GPP TS 38.321 V16.4.0.

As can be seen from the tables in the technical specification, LCID values are a limited resource. Whilst there are some reserved LCIDs available for new uses, for example, new MAC CEs, even those reserved values are limited. For example, as can be seen in the tables of the technical specification, only 12 LCID values are allocated to the downlink-shared channel (DL-SCH) and 10 LCID values are allocated to the uplink-shared channel (UL-SCH).

Use of the finite LCID resource within a communication network may be restrictive. It is recognised that the bits allocated to one or more fields of an LCID may be utilised to further support effective communication in a network.

BRIEF SUMMARY

The scope of protection sought for various example embodiments of the invention is set out by the independent claims. The example embodiments and features, if any, described in this specification that do not fall under the scope of the independent claims are to be interpreted as examples useful for understanding various embodiments of the invention.

According to various, but not necessarily all, example embodiments there is provided: an apparatus, comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to: determine that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; determine the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; and encode the information for transmission in a message including the at least one Logical Channel Identifier field in accordance with the encoding configuration.

In some embodiments, the apparatus may comprise: a terminal apparatus, or user equipment apparatus in a communication network.

In some embodiments, the use of the at least one Logical Channel Identification LCID index to transfer information to support communication within a communication network may be set

or fixed in the 3GPP specification.

In some embodiments, causing the apparatus to determine that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network may comprise: referring to an internal look up table.

In some embodiments, causing the apparatus to determine that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network may comprise: receiving an indication that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network.

In some embodiments, the indication that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network may be received in an indication from the network.

In some embodiments, the information to support communication within a communication network comprises: additional, extra or further information not typically encoded within a field of a Logical Channel Identifier index.

In some embodiments, the information comprises: information to support communication within a communication network as part of a random access procedure.

In some embodiments, the message in which the at least one Logical Channel Identifier field is included comprises: a Msg3 (for example, in relation to a 4-step random access procedure) message or a MsgA message (for example, in relation to a 2-step random access procedure). In some embodiments, the information and message are selected such that, on the basis of the information and message, a network may determine how to decode a medium access control (MAC) Packet Data Unit (PDU).

In some embodiments, the information comprises: dynamic user equipment assistance information to support communication within a communication network In some embodiments, the information may comprise an indication of a desired change of apparatus capabilities (for example, due to the apparatus overheating), based on encoding such information in at least one LCID rather than using one or more indication typically communicated between apparatus and a network as part of, for example, a Radio Resource Control (RRC) protocol or procedure. Use of LCID may result in a more dynamic and responsive communication network.

In some embodiments, the message in which the at least one Logical Channel Identifier field is included comprises: a Common Control Channel CCCH message.

In some embodiments, the Common Control Channel Message comprises one of the following: a Radio Resource Control RRC connection set up message; or a Radio Resource Control RRC resume message; or a Radio Resource Control RRC reestablishment message; or a System Information request message.

In some embodiments, the information comprises: information to support communication of UE capability information between network nodes as part of initial establishment of a communication link.

In some embodiments, the information comprises: at least one of the following: Common Control Channel CCCH Service data Unit SDU message size; or an extension of a Media Access Channel MAC header or sub header; or an indication of uplink repetition; or user equipment assistance information; or an indication of one or more user equipment preference for a parameter of a Small Data Transfer SDT procedure; or an indication of channel state information; or an indication of user equipment buffer status; or an indication of user equipment power headroom; or an indication of one or more user equipment capability; or status or quantity of measured inter-frequency neighbour cells; or the presence of a stored UE configuration.

In some embodiments, the encoding configuration to allow the information to be encoded within the field of the at least one Logical Channel Identifier index comprises: an indication of a mapping between a bit or group of bits forming the at least one Logical Channel Identifier field and the information which is to be indicated using the bit or group of bits.

In some embodiments, the at least one Logical Channel Identifier field is interpreted as a bit string in which each bit or group of bits maps to a different indicator of information.

According to various, but not necessarily all, example embodiments, there is provided a method, comprising: determining that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; determining an indication of the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; and encoding the information for transmission in a message including the at least one Logical Channel Identifier field in accordance with the encoding configuration.

In some embodiments, the method may be performed by an apparatus comprising: a terminal apparatus, or user equipment apparatus in a communication network.

or fixed in the 3GPP specification.

In some embodiments, determining that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network may comprise: referring to an internal look up table.

In some embodiments, determining that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network may comprise: receiving an indication that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network.

In some embodiments, the indication that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network may comprise receiving that information in an indication from the network.

In some embodiments, the information comprises: information to support communication within a communication network as part of a connection setup or random access procedure.

In some embodiments, the information comprises: dynamic user equipment assistance information to support communication within a communication network.

In some embodiments, the information may comprise: an indication of a desired change of apparatus capabilities (for example, due to the apparatus overheating). According to some embodiments, an indication of a desired change in capabilities may be encoded in at least one LCID.

In some embodiments, the encoding configuration to allow the information to be encoded within the field of the at least one Logical Channel Identifier index comprises: an indication of a mapping between a bit, or group of bits, forming the at least one Logical Channel Identifier field and the information which is to be indicated using the bit or group of bits.

According to various, but not necessarily all, example embodiments there is provided: an apparatus, comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to: determine that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; transmit an indication of the information and an encoding configuration to allow the additional information be encoded within a field of the at least one Logical Channel Identifier index; receive a message including the at least one Logical Channel Identifier field; and decode the information in the received at least one Logical Channel Identifier field in accordance with the encoding configuration.

In some embodiments, the apparatus comprises: a network node in the communication network) In some embodiments, the apparatus is configured to transmit an indication that at least one Logical Channel Identification LCID field is to be used to transfer information to support communication within a communication network.

In some embodiments, the apparatus is configured to transmit the indication that at least one Logical Channel Identification LCID field is to be used to transfer information to support communication within a communication network within one of the following: broadcast signalling; or dedicated signalling.

In some embodiments, the dedicated signalling comprises Radio Resource Control messaging or Media Access Control messaging.

In some embodiments, the apparatus is configured to transmit an indication of a message type within which the at least one Logical Channel Identification LCID field is to be used to transfer information to support communication within a communication network.

In some embodiments, the message type comprises: a New Radio NR Msg 1 or a New Radio NR Msg3 or a New Radio NR MsgA In some embodiments, the information to support communication within the communication network differs in dependence upon the message type within which it is to be used.

According to various, but not necessarily all, example embodiments there is provided: a method, comprising: determining that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; transmitting an indication of the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; receiving a message including the at least one Logical Channel Identifier field; and decoding the information in the received at least one Logical Channel Identifier field in accordance with the encoding configuration.

In some embodiments, the method is performed by: a network node in the communication network.

In some embodiments, the method comprises: transmitting an indication that at least one Logical Channel Identification LCID field is to be used to transfer information to support communication within a communication network.

In some embodiments, the method comprises: transmitting the indication that at least one Logical Channel Identification LCID field is to be used to transfer information to support communication within a communication network within one of the following: broadcast signalling; or dedicated signalling.

In some embodiments, the method comprises: transmitting an indication of a message type within which the at least one Logical Channel Identification LCID field is to be used to transfer information to support communication within a communication network.

According to some, but not necessarily all, example embodiments, there is provided: a computer program product operable, when executed on a computer, to perform a method comprising the steps of: determining that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; determining an indication of the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; and encoding the information for transmission in a message including the at least one Logical Channel Identifier field in accordance with the encoding configuration.

According to some, but not necessarily all, example embodiments, there is provided: a computer program product operable, when executed on a computer, to perform a method comprising the steps of: determining that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; transmitting an indication of the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; receiving a message including the at least one Logical Channel Identifier field; and decoding the information in the received at least one Logical Channel Identifier field in accordance with the encoding configuration.

According to some, but not necessarily all, example embodiments, there is provided: an apparatus, comprising: means configured to determine that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; means configured to determine the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; and means configured to encode the information for transmission in a message including the at least one Logical Channel Identifier field in accordance with the encoding configuration.

According to some, but not necessarily all, example embodiments, there is provided: an apparatus, comprising: circuitry configured to determine that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; circuitry configured to determine the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; and circuitry configured to encode the information for transmission in a message including the at least one Logical Channel Identifier field in accordance with the encoding configuration.

According to some, but not necessarily all, example embodiments, there is provided: an apparatus, comprising: means configured to determine that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; means configured to transmit an indication of the information and an encoding configuration to allow the additional information be encoded within a field of the at least one Logical Channel Identifier index; means configured to receive a message including the at least one Logical Channel Identifier field; and means configured to decode the information in the received at least one Logical Channel Identifier field in accordance with the encoding configuration.

According to some, but not necessarily all, example embodiments, there is provided: an apparatus, comprising: circuitry configured to determine that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; circuitry configured to transmit an indication of the information and an encoding configuration to allow the additional information be encoded within a field of the at least one Logical Channel Identifier index; circuitry configured to receive a message including the at least one Logical Channel Identifier field; and circuitry configured to decode the information in the received at least one Logical Channel Identifier field in accordance with the encoding configuration.

Further particular and preferred aspects are set out in the accompanying independent and dependent claims. Features of the dependent claims may be combined with features of the independent claims as appropriate, and in combinations other than those explicitly set out in the claims.

Where an apparatus feature is described as being operable to provide a function, it will be appreciated that this includes an apparatus feature which provides that function or which is adapted or configured to provide that function.

BRIEF DESCRIPTION

Some example embodiments will now be described with reference to the accompanying drawings in which: FIG. 1A and 1B illustrate schematically an example embodiment of the subject matter described herein; FIG. 2 illustrates schematically a specific example of the subject matter described herein using two bit groups having been allocated specific meanings; FIG. 3 is a signalling diagram illustrating one possible implementation of signalling between a network and a user equipment in accordance with one possible arrangement; FIG. 4 illustrates schematically some components of a network including nodes according to 20 some arrangements; and FIG. 5 illustrates schematically steps of methods performed in accordance with some arrangements.

DETAILED DESCRIPTION

Before discussing the example embodiments in any more detail, first an overview of background context within which arrangements are to be understood is provided.

Logical channel IDs (LCIDs) in cellular communication systems are used for indicating scheduling priorities for a particular set of data, and for allowing identification of which data is sent between, for example, a UE and the network. In particular, LCIDs used for Common Control Channels CCCH are also used to identify the format of the Media Access Control MAC header and the Radio Resource Control RRC message size for a particular message, since UE capabilities are not known in advance and a network doesn't always know which UE sent which message (in other words, Contention Based Random Access CBRA allows for collisions).

The MAC determines the Protocol data Unit PDU payload for CCCH as follows (from the 3GPP specification Rel-17 version of TS38.321, which also considers the extended LCID (eLCID)): 6.1.2 MAC PDU (DL-SCH and UL-SCH except transparent MAC and Random Access Response) A MAC PDU consists of one or more MAC subPDUs. Each MAC subPDU consists of one of the following: A MAC subheader only (including padding); A MAC subheader and a MAC SDU; A MAC subheader and a MAC CE; A MAC subheader and padding.

The MAC SDUs are of variable sizes.

Each MAC subheader corresponds to either a MAC SDU, a MAC CE, or padding.

A MAC subheader except for fixed sized MAC CE, padding, and a MAC SDU containing UL CCCH consists of the header fields R/F/LCID/(eLCID)/L. A MAC subheader for fixed sized 20 MAC CE, padding, and a MAC SDU containing UL CCCH consists of the two header fields R/LCID/(eLCID).

The specification sets out MAC header formats, and a MAC Uplink PDU has a known general construction.

5G/NR deploys two CCCH Service data Unit SDU message sizes: 48 and 64 bits. All RRC request messages except RRCResumeRequestl have a size of 48 bits. The size of the CCCH SDU is indicated by a UE by means of an LCID value or index based upon which a network can determine that there is a CCCH SDU and can know its size (and no L field is required for the MAC subheader): Table 6.2.1-2 Values of LCID for UL-SCH Codepointllndex LCID values 0 CCCH of size 64 bits (referred to as "CCCH1" in TS 38.331 [5]), except for a RedCap UE 1-32 Identity of the logical channel of DCCH and DTCH 33 Extended logical channel ID field (two-octet eLCID field) 34 Extended logical channel ID field (one-octet eLCID field) CCCH of size 48 bits (referred to as "CCCH" in TS 38.331 [5]) for a RedCap UE 36 CCCH of size 64 bits (referred to as "CCCH1" in TS 38.331 [5]) for a RedCap UE 37-42 Reserved 43 Truncated Enhanced BFR (one octet C,) 44 Timing Advance Report Truncated Sidelink BSR 46 Sidelink BSR 47 Reserved 48 LBT failure (four octets) 49 LBT failure (one octet) BFR (one octet C) 51 Truncated BFR (one octet C) 52 CCCH of size 48 bits (referred to as "CCCH" in TS 38.331 [5]) except for a RedCap UE 53 Recommended bit rate query 54 Multiple Entry PHR (four octets CI) Configured Grant Confirmation 56 Multiple Entry PHR (one octet C,) 57 Single Entry PHR 58 C-RNTI 59 Short Truncated BSR Long Truncated BSR 61 Short BSR 62 Long BSR 63 Padding There are a number of LCID indexes allocated to UL-SCH, but that number is restricted so it is difficult for a network to allow for different message sizes for CCCH messages, since each such case would require a new LCID to be allocated, as can be seen from the tables above and below.

LCID=0 was originally reserved for CCCH since LTE, with additional LCIDs (e.g. in NR, LCIDs 35, 36 and 52 as shown above) later extended to indicate specific CCCH messages. As can also be seen, the same principle has been continuously used: A new LCID is allocated to indicate specific type of message. Thus, reserving additional LCID values would require either using up one of the remaining 6 LCID values, or using one of the e-LCID values, which would then increase overall message (header) size substantially. eLCIDs were introduced in Rel-16 to allow more LCIDs to be used in Downlink DL and Uplink UL. eLCIDs extend the address space for MAC LCIDs from 6 bits to either 8 bits or 16 bits, which means the use of eLCID comes at the cost of message (header) size.

Table 6.2.1-2 Values of LCID for UL-SCH Codepointllndex LCID values 00000 CCCH 00001-01010 Identity of the logical channel 01011 CCCH 01100 CCCH 01101 CCCH and Extended Power Headroom Report 01110 Reserved 01111 Timing Advance Report

10000 Extended logical channel ID field

10001 DCQR and AS RAI 10010 AUL confirmation (4 octets) 10011 AUL confirmation (1 octet) 10100 Recommended bit rate query 10101 SPS confirmation 10110 Truncated Sidelink BSR 10111 Sidelink BSR 11000 Dual Connectivity Power Headroom Report 11001 Extended Power Headroom Report 11010 Power Headroom Report 11011 C-RNTI 11100 Truncated BSR 11101 Short BSR 11110 Long BSR 11111 Padding Table 6.2.1-2a Values of eLCID for UL-SCH Codepoint Index LCID values 000000-000110 32-38 Identity of the logical channel 000111-111111 39-95 Reserved LTE MAC operates in a similar manner with certain LCIDs specifically reserved for CCCH: "For NB-IoT only the following LCID values for DL-SCH are applicable: CCCH, Identity of the logical channel, DCQR Command, SC-PTM Stop Indication, SC-MCCH/SC-MTCH, UE Contention Resolution Identity, Timing Advance Command, DRX Command, Differential Koffset and Padding".

Before discussing the example embodiments in any more detail, first an overview will be provided.

Described arrangements recognise that it is possible to use one or more Logical Channel Identifier (LCID) indices (for example, one or more of LCIDs 0-63) in support of, for example, Common Control Channel (CCCH) messaging. According to some arrangements, CCCH messaging can then be effectively used in a network to support, for example, RRC connection setup, resume, re-establishment, and/or system information requests. Described arrangements achieve such functionality by operating to extend the interpretation of a typical LCID index. In the following, and the foregoing, a distinction is made between a Logical Channel identifier index and a Logical Channel identifier field. In particular, "index" signifies the value of the LCID, whereas "field" is used to mean some of the bits that are used/allocated generally to an encoding of the LCID value.

Some arrangements are such that a network is configured to indicate to UE, for example, via dedicated signalling and/or, for example, in broadcast system information messaging or signalling, that the network supports extended LCID usage for CCCH.

Some arrangements may be such that implementation of extended LCID usage, for example in CCCH messaging, is a default. Such an implementation may, for example, be of particular use in a 6G system where the design takes such considerations into account from the first release onwards.

In one example arrangement, a network may be configured to indicate, either in dedicated signalling and/or in broadcast system information, what kind of information the LCID may be used to support. For example, a network may indicate the information that it would prefer to receive from a UE.

In one example arrangement, if a UE determines that extended LCID usage is supported by a network, it may be configured to use a reserved set of LCIDs, comprising, for example, one or more known LCID, to indicate information relating to certain aspects of, for example, uplink (UL) messages, to the network. That information may, for example, comprise one or more of, for example: CCCH Service Data Unit (SDU) message size, extension of MAC header, extension of MAC subheader, UL repetition, assistance information, such as UE preference for Small data Transmission (SDT) procedures, an indication of channel state information, UE buffer status, power headroom, UE capability information, UE serving or neighbour cell measurement quality, status or quantity of measured inter-frequency neighbour cells that could be used as serving cells, presence of a stored configuration and similar.

Since the technical specification specifies 64 LCID values, this translates to 6 bits of information that can be used, for example, in an UL indication. It should be noted that naturally (especially in a 5G system), the number of bits assigned to the LCID field may change and be extended, for example, to 7 or 8 bits, but the principles described in relation to the 6 bits can be extended accordingly. It will be appreciated that since the same Random Access Channel (RACH) can, in some instances, be used by IDLE/INACTIVE mode UEs and CONNECTED mode UEs, at least one LCID may need to be reserved for use to indicate a Cell Radio Network Temporary Identifier (C-RNTI) MAC CE for a CONNECTED mode UE.

As a result, in practice, the maximum current number of LCIDs which could be used for extending information to be exchanged, for example, in CCCH messaging, would currently be 63 indices, or more generally: the LCID index space minus one.

According to arrangements, a meaning of each bit, or a bit group (wherein a bit group could be defined as consisting of 2 or more bits out of all the available bits) may be configured by the network (for example, in system information or in dedicated signalling), fixed in specification, or a combination of both (for example, a first bit group may always indicate certain message size(s), and remaining bits or bit groups may be configurable). The meaning could also be defined via a look up table that defines the meaning of each bit combination for a specific size of a bit group, which is then defined in a specification, and used internally by UE and network.

According to some arrangements, an LCID-based information indicator may be such that the content of the indication may be different in different uplink or downlink messages. By way of example, if considering an uplink use of the LCID to support indication of additional information within a network, arrangements may be such that Msg3/MsgA LCID in uplink messaging may be used to include an indication of information relating to one or more UE capability, Msg4/MsgB may be used to convey an indication that network would like to receive additional capabilities from the UE, and MsgS LCID may be used to indicate additional capabilities to the network. The use of the LCID may be defined separately for each case in specifications. According to some possible arrangements, the LCID used in Msg3 and MsgA could be used to provide different information to the network. Furthermore, in some implementations, for example, where preamble partitioning is implemented, the interpretation of an LCID may depend upon the UE type or of the used preamble partition to be implemented: for example, the interpretation of LCID may be different for RedCap UEs, UEs with a specific configuration identified by a preamble partition, such as UEs having stored network configuration, RedCap UEs, UEs using enhanced coverage, UEs being configured with SDT, or UEs utilized slice-specific cell reselection mechanisms.

According to some arrangements, it may be specified that in relation to an initial Physical Uplink Shared Channel (PUSCH) transmission from a UE to the network, in other words, a Random Access Msg3 or MsgA or initial Configured Grant transmission, for example, in case of a Small Data Transmission (SDT) procedure, the first MAC subheader may not contain a LCID field. For example, the first bit of the first MAC subheader in the MAC PDU may indicate whether the UE is an IDLE/INACTIVE mode UE (for example by allocating bit value '0') or a CONNECTED mode UE (for example by allocating bit value '1'). In an alternative example, the first bit of the LCID space (i.e., 3R1 bit of the MAC subheader in the case of a NR system) can be used for this purpose. Such arrangements may allow for the encoding of anything in the bits that are normally allocated to LCID indication. A network may be configured such that it is known to decode a MAC PDU differently since the MAC PDU is received as part of Random-Access procedure in Msg3/MsgA or as part of initial Configured Grant (CG) transmission. Once appropriately configured, a network and UE may operate such that the traditional LCID bit space (comprising, for example, 5 or 6 bits) could be used in support of communication of new information fields consisting of, for example, 1 or more bits. Those bits may, in some arrangements, be used to communicate indications of, for example, different CCCH SDU sizes, buffer/power headroom/channel state information or similar.

FIG. 1A and 1B illustrate schematically an example embodiment of the subject matter described herein. In the examples of FIG. 1, two possible examples of a reinterpreted LCID are shown. It will be appreciated that 5 bits can be used to represent numbers from 0-31.

The addition of one is needed to allow the 5 bits to represent numbers from 1-32.

FIG. 1A and 1B illustrates the generic principle of how 5 of the 6 bits of an LCID can be used as a bit group 100. In the case shown in FIG. 1A 5 bits of the LCID, can be used, for example, to indicate UE related information in a CCCH message.

FIG. 1A shows how a bit group of 5 bits 100 which usually map to possible LCIDs (LCID 30, LCID 20, LCID 13 and LCID 7) can be reused and map to an encoding of different information for inclusion in messaging.

FIG. 1B shows how the 5 bits which usually map to possible LCI Ds (LCID 30, LCID 20, LCID 13 and LCID 7) can be split into a bit group of two bits 120 and a bit group of 3 bits 130 and each bit group can be reused and map to an encoding of different information for inclusion in messaging.

FIG. 2 illustrates schematically a specific example of the subject matter described herein using two bit groups which have been allocated specific meanings. FIG. 2 shows how the 5 bits which usually map to possible LCIDs (LCID 30, LCID 20, LCID 13 and LCID 7) can be split into a bit group of two bits 220 which can be used to encode information which indicates message size and a bit group of 3 bits 230 which can be used to include Channel State Information (CSI) using two of the three bits, and UE coverage as one bit. It can then be understood that the bits of each bit group can be reused and map to an encoding of additional information from the UE to the network for inclusion in messaging. That additional information is encoded in resource which is already "allocated" or included in existing network messaging, and therefore the UE can be enabled to provide additional information in support of efficient network operation without incurring an additional overhead.

Various implementations are possible. According to one implementation, the LCID can be interpreted as a bit string that indicates multiple bit positions instead of defining a specific logical channel.

According to some implementations, the bit positions may be considered to be defined as one or more bit groups, each bit and/or bit group having a specific meaning or interpretation.

According to some implementations, the meaning of the bits in a bit group may be fixed or pre-allocated in a specification such that each bit indicates, for example, a specific UE capability or capabilities.

According to some implementations, some bits may have a fixed meaning (for example, the message size bits shown as 220 in FIG. 2) whilst the meaning of other bits within the LCID string or within a bit group of the string can be configured by, for example, the network to map to requested information (for example, the network may have configured the three bits 230 to indicate "UE channel information" in the form of Channel State information and UE coverage as shown in FIG. 2).

According to some implementations, a UE may be configured to include different information in different bit groups (i.e. different UE information) in different UL messages (for example, a UE may be configured to use LCID bits to include information in Msg3 which is different to a use of LCID bits to indicate information relating to, for example, UE capabilities in Msg5.

According to some implementations, LCID interpretation may be based on a selected preamble or preamble group.

FIG. 3 is a signalling diagram illustrating one possible implementation of signalling between a network 20 and a user equipment 10 in accordance with one possible arrangement.

S1: According to some implementations, a network may be configured to indicate to UE 10 that a method which extends use of the LCID is to be implemented or supported.

S2: Msg1, the UE and network are configured to communicate via a Random Access Preamble.

S3: Msg2: The network may be configured to respond to the Random Access Preamble with a Random Access Response Message which includes an Uplink Grant.

S4: The UE may receive the Uplink grant, and in some implementations, the network may inform the UE as part of the Random Access Response that that a method which extends use of the LCID is to be implemented or supported. According to some implementations, the UE may also be informed of a specific use of extended LCID. In one implementation, the use of extended LCID may comprise use of extended LCID in Msg3 to indicate UE capabilities.

S5: Msg3, the UE may be configured to send an RRC connection request in which the LCID is repurposed, and the repurposing of the bits forming the LCID allows the network to interpret the LCID in an extended way, so that it provides information to the network regarding, for example UE capabilities.

S6: Msg4, the network is configured to send the UE an RRCSetup message, which may use, or be based upon the LCID-based UE capabilities received.

S7: The UE may be configured to transmit to the network an RRCSetupComplete message. That messaging may also used the extended LCID principles and therefore the UE may use the bits of the LCID to indicate additional capabilities or information to the network using the LCID.

It will be appreciated that features described may be implemented in various ways. By way of example, according to some implementations, a network may be configured to indicate to UE in the network that the LCID can be reused or adapted in accordance with the principles described herein. The network may, for example, inform the UE via system information, which may include transmission of a necessary indication that extended LCID is supported via a SIB (System Information Block). In some implementations, the network may inform UE via dedicated signalling. The dedicated signalling may, for example, comprise least one of RRC or MAC signalling.

In some implementations, upon initiation of a small data transfer (SDT) procedure, the LCID may be repurposed or reinterpreted so that a UE may be configured to use the LCID to indicate one or more of: a rough amount of SDT data (for example, small BSR) in the buffer; rough channel state information (for example, whether RSRP is better or worse than a network configured threshold; whether subsequent transmissions in UUDL are expected; and/or rough power headroom (for example, whether the power headroom is better or worse than a network configured threshold); the status or quantity of measured inter-frequency neighbour cells; or the presence of a stored UE configuration.

In some implementations, a portion of all available LCID space is allocated for the "extended" reuse in accordance with described principles. For example, in one implementation, half of the LCID space is reserved for extended use, for example, the LCID indices 1-32 which would typically be used for identity of the logical channel of DCCH and DTCH in NR. the remaining LCIDs may continue to be used in their traditional sense, for example, in the example above, LCIDs 33-64 could continue to be use for possible MAC CEs in the Msg3/MsgA.

According to come implementations, only a first MAC subheader in the MAC PDU is encoded based on the proposed approach. For example, the MAC PDU in which the approach in 35 accordance with arrangements is deployed may comprise the MAC PDU encoded for Msg3/MsgA of a Random Access procedure.

FIG. 4 illustrates schematically some components of a network including nodes according to some arrangements; and FIG. 5 illustrates schematically steps of methods performed in accordance with some arrangements.

FIG. 4 illustrates schematically some components of a network including nodes according to some arrangements. The network 1000 comprises a plurality of network nodes 1200 in communication with user equipment 1100.

The user equipment 1100 takes the form of an apparatus, comprising: means 1110 configured to determine that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network 1000; means 1120 configured to determine the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; and means 1130 configured to encode the information for transmission in a message including the at least one Logical Channel Identifier field in accordance with the encoding configuration. The user equipment may further comprise means to transmit the message to another apparatus, for example, network node, within the communication network.

The network node 1200 takes the form of an apparatus, comprising: means 1210 configured to determine that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; means 1220 configured to transmit an indication of the information and an encoding configuration to allow the additional information be encoded within a field of the at least one Logical Channel Identifier index; means 1230 configured to receive a message including the at least one Logical Channel Identifier field; and means 1240 configured to decode the information in the received at least one Logical Channel Identifier field in accordance with the encoding configuration.

FIG. 5 illustrates schematically steps of methods performed in accordance with some arrangements.

The user equipment 1100 may be configured to perform a method comprising the steps of: 5110: determining that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; 5120: determining an indication of the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; and 5130: encoding the information for transmission in a message including the at least one Logical Channel Identifier field in accordance with the encoding configuration.

The network node 1200 may be configured to perform a method comprising the steps of: 5210: determining that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; 5220: transmitting an indication of the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; 5230: receiving a message including the at least one Logical Channel Identifier field; and 5340: decoding the information in the received at least one Logical Channel Identifier field in accordance with the encoding configuration.

It will be appreciated that approaches in accordance with the principles of described arrangements may allow for more information to be carried to a network from a UE using, for example, the very limited Msg3/MsgA Transport Block (TB) size. That additional information may comprise additional information relating to the connection establishment and/or UE situation/capabilities at the point of RRC request. Approached described can be implemented such that no additional bytes need to be reserved to indicate the additional information, and instead the exchange of additional information can be achieved using the same number of bits as, for example, a minimum size NR Msg3/MsgA size of 56 bits (1 byte MAC subheader + 6 bytes CCCH SDU).

A person of skill in the art would readily recognize that steps of various above-described methods can be performed by programmed computers. Herein, some embodiments are also intended to cover program storage devices, e.g., digital data storage media, which are machine or computer readable and encode machine-executable or computer-executable programs of instructions, wherein said instructions perform some or all of the steps of said above-described methods. The program storage devices may be, e.g., digital memories, magnetic storage media such as a magnetic disks and magnetic tapes, hard drives, or optically readable digital data storage media. The embodiments are also intended to cover computers programmed to perform said steps of the above-described methods. The tern non-transitory as used herein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g. RAM vs ROM).

As used in this application, the term "circuitry" may refer to one or more or all of the following: (a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and (b) combinations of hardware circuits and software, such as (as applicable): (i) a combination of analog and/or digital hardware circuit(s) with software/firmware and (ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and (c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware.

The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

Although example embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed.

Features described in the preceding description may be used in combinations other than the combinations explicitly described.

Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.

Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

CLAIMS1. An apparatus, comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to: determine that at least one Logical Channel Identification LCD index is to be used to transfer information to support communication within a communication network; determine the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; and encode the information for transmission in a message including the at least one Logical Channel Identifier field in accordance with the encoding configuration.
2. An apparatus according to claim 1, wherein the information comprises additional, extra or further information not typically encoded within a field of a Logical Channel Identifier index.
3. An apparatus according to claim 1, wherein the information comprises: information to support communication within a communication network as part of a random access 20 procedure.
4. An apparatus according to claim 1, wherein the information comprises: dynamic user equipment assistance information to support communication within a communication network.
5. An apparatus according to any one of claims 1 to 4, wherein the message in which the at least one Logical Channel Identifier field is included comprises a Common Control Channel CCCH message.
6. An apparatus according to any preceding claim, wherein the information comprises: information to support communication of UE capability information between network nodes as part of initial establishment of a communication link.
7. An apparatus according to claim 6, wherein the information comprises: at least one of the following: Common Control Channel CCCH Service data Unit SDU message size; or an extension of a Media Access Channel MAC header or sub header; or an indication of uplink repetition; or user equipment assistance information; or an indication of one or more user equipment preference for a parameter of a Small Data Transfer SDT procedure; or an indication of channel state information; or an indication of user equipment buffer status; or an indication of user equipment power headroom; or an indication of one or more user equipment capability; or status or quantity of measured inter-frequency neighbour cells; or the presence of a stored UE configuration.
8. An apparatus according to any preceding claim, wherein the encoding configuration to allow the information be encoded within the field of the at least one Logical Channel Identifier index comprises an indication of a mapping between a bit or group of bits forming the at least one Logical Channel Identifier field and the information which is to be indicated using the bit or group of bits.
9. An apparatus according to claim 8, wherein the at least one Logical Channel Identifier field is interpreted as a bit string in which each bit or group of bits maps to a different indicator of information.
10. An apparatus, comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to: determine that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; transmit an indication of the information and an encoding configuration to allow the additional information be encoded within a field of the at least one Logical Channel Identifier index; receive a message including the at least one Logical Channel Identifier field; and decode the information in the received at least one Logical Channel Identifier field in accordance with the encoding configuration.
11. An apparatus according to claim 10, wherein the apparatus is configured to transmit an indication that at least one Logical Channel Identification LCID field is to be used to transfer information to support communication within a communication network.
12. An apparatus according to claim 11, wherein the apparatus is configured to transmit the indication that at least one Logical Channel Identification LCID field is to be used to transfer information to support communication within a communication network within one of the following: broadcast signalling; or dedicated signalling.
13. An apparatus according to claim 12, wherein the dedicated signalling comprises Radio Resource Control messaging or Media Access Control messaging.
14. An apparatus according to any one of claims 10 to 13, wherein the apparatus is configured to transmit an indication of a message type within which the at least one Logical Channel Identification LCID field is to be used to transfer information to support communication within a communication network.
15. An apparatus according to claim 14, wherein the information to support communication within the communication network differs in dependence upon the message type within which it is to be used.
16. A method, comprising determining that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; determining an indication of the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; and encoding the information for transmission in a message including the at least one Logical Channel Identifier field in accordance with the encoding configuration.
17. A method, comprising determining that at least one Logical Channel Identification LCID index is to be used to transfer information to support communication within a communication network; transmitting an indication of the information and an encoding configuration to allow the information be encoded within a field of the at least one Logical Channel Identifier index; receiving a message including the at least one Logical Channel Identifier field; and decoding the information in the received at least one Logical Channel Identifier field in accordance with the encoding configuration.
18. A computer program product operable, when executed on a computer, to perform the method of claim 16 or claim 17.