Method and apparatus for configuring network coding and controlling network coding activation

Abstract

The present invention relates to a method for wireless communication between a base station and a user equipment, wherein the method comprises: sending a data radio bearer configuration by the base station; and sending a packet between the base station and the user equipment according to the data radio bearer configuration; wherein the data radio bearer configuration comprises a network coding configuration; and the sent packet is sent according to the network coding configuration.

Description

Technical Field

[0001] The present invention relates to a method and apparatus for configuring network coding of devices in a radio communication system and controlling the activation of network coding. The present invention more particularly relates to data transmission robustness improvement of Ultra-Reliable Low Latency Communication (URLLC). Background Art

[0002] Wireless communication systems are deployed in large numbers to address a wide range of applications ranging from mobile broadband, massive machine type communications, and ultra-reliable low latency communications (URLLC). Such systems allow multiple user equipment (UE) or mobile terminals (MT) to share a wireless medium to exchange several types of data content (e.g., video, voice, messaging, etc.) over a radio access network (RAN) through one or more base stations. Examples of such wireless multiple access communication systems include systems based on the third generation partnership project (3GPP) standard (such as the fourth generation (4G) long term evolution (LTE) or the recent fifth generation (5G) new air interface (NR) system, etc.) or systems based on the IEEE 802.11 standard (such as WiFi, etc.).

[0003] URLLC type of communication is particularly relevant in Industrial Internet of Things (I-IoT or IIOT or IIoT) environments where communication reliability and therefore communication service availability is crucial to prevent service interruptions, while low latency related to the end-to-end delay of the communication is required, for example to avoid introducing downtime of equipment or to ensure predictive deterministic data reception.

[0004] Several techniques can be considered to ensure communication reliability, such as Automatic Repeat Request (ARQ) or on-demand retransmission schemes based on acknowledgement messaging, even if the low latency requirement is difficult to meet.

[0005] To reduce this problem, a packet duplication mechanism is provided, called Packet Data Convergence Protocol (PDCP) T-duplicate in 3GPP and described in specification TS 38.323, where packets are systematically sent and received on two different carrier frequencies instead of one. However, packet duplication is not optimal because it lacks coding diversity while doubling the bandwidth requirement.

[0006] The introduction of network coding for RAN communications leads to consideration of appropriate signaling between the involved radio devices, ie UE and base station. In particular, before enabling the network coding feature, the network coding configuration needs to be shared between the UE and the base station.

[0007] In practice, since a wide range of network coding configurations may be considered, the UE and the base station should agree on the network coding configuration that is selected and applied.

[0008] For example, the network coding scheme as well as the coefficients used to generate the linear combinations and their mapping onto the various communication channels should be determined and agreed upon between the base station and the UE prior to any further activation and potential deactivation of network coding.

[0009] Several 3GPP specification documents (TS 38.300, TS 37.340, TS 38.323, TS 38.331 ...) provide specifications for multiple connections or PDCP duplication setups. Summary of the invention

[0010] The present invention has been designed to solve one or more of the aforementioned problems. A signaling method is provided for establishing a network coding (NC) configuration between 5G devices while describing an associated control protocol for activation and deactivation.

[0011] In one embodiment of the present invention, the NC configuration is shared in the form of a specific field added in an information element (IE) carried in a radio resource control (RRC) message. In another embodiment of the present invention, all or part of the NC configuration can be embedded in the header of the encoded data packet. Other embodiments of the present invention cover combinations of the aforementioned embodiments.

[0012] In one embodiment of the present invention, a network coding (NC) activation / deactivation notification is established by means of a specific field added in an information element (IE) carried in one or more RRC messages. In another embodiment of the present invention, the NC activation / deactivation command is embedded in a dedicated field of a coding data packet.

[0013] In another embodiment of the present invention, the UE may send an activation / deactivation request by sharing state information carried in an RRC message.

[0014] The protocol messages used for both NC configuration and NC activation / deactivation processes should belong to a message set standardized by 3GPP.

[0015] According to a first aspect of the present invention, a method for wireless communication between a base station and a user equipment is provided, wherein the method comprises: sending a data radio bearer configuration by the base station; and sending packets between the base station and the user equipment according to the data radio bearer configuration; wherein: the data radio bearer configuration comprises a network coding configuration; and the sent packets are sent according to the network coding configuration.

[0016] In an embodiment, the network coding configuration is embedded in one or more network coding packets.

[0017] In an embodiment, the method further comprises: receiving, by the base station, a configuration confirmation message to confirm the use of the configuration of the user equipment; and upon receiving the configuration confirmation message, initiating packet transmission according to the network coding configuration.

[0018] In an embodiment, the network coding configuration comprises an indication related to a network coding activation state.

[0019] In an embodiment, the network coding activation state is an activation command or a deactivation command.

[0020] In an embodiment, said network coding configuration comprises an indication regarding a transmission mode to be applied for sending packets according to said network coding.

[0021] In an embodiment, said transmission mode is a multi-radio connection.

[0022] In an embodiment, the transmission mode is carrier aggregation.

[0023] In an embodiment, said network coding configuration comprises information about the number of logical channels to be used for sending packets according to said network coding.

[0024] In an embodiment, said network coding configuration comprises information about a network coding scheme to be used for sending packets according to said network coding.

[0025] In an embodiment, said network coding configuration comprises information about network coding coefficient values ​​to be used for sending packets according to said network coding.

[0026] In an embodiment, the information related to said network coding coefficient values ​​comprises information related to the number of network coding coefficient values ​​to be used for sending packets according to said network coding.

[0027] In an embodiment, in a case where the network coding configuration does not include any information related to the network coding coefficient values, predefined network coding coefficient values ​​are used for network coding.

[0028] In an embodiment, the information related to the network coding coefficient values ​​comprises information related to a mapping of network coding coefficient values ​​to logical channels.

[0029] In an embodiment, in case said network coding configuration does not comprise any information about mapping of network coding coefficient values ​​to logical channels, a predefined mapping of network coding coefficient values ​​to logical channels is applied.

[0030] In an embodiment, the method further comprises: selecting a logical channel to be used for network coding.

[0031] In an embodiment, the method further comprises selecting between carrier aggregation and multi-radio connection as a transmission mode for sending packets according to the network coding configuration.

[0032] In an embodiment, the method further comprises: selecting a plurality of network coding schemes to be used for sending packets according to the network coding.

[0033] In an embodiment, the method further comprises: setting a plurality of radio link control entities associated with the logical channel.

[0034] In an embodiment, the method further comprises: before sending the data radio bearer configuration including the network coding configuration to the user equipment, checking, by the base station, the need for network coding enabling.

[0035] In an embodiment, the method further comprises: before sending the data radio bearer configuration including the network coding configuration to the user equipment, checking, by the base station, feasibility of enabling the network coding.

[0036] In an embodiment, when neither carrier aggregation nor multiple radio connection transmission mode can be applied between the base station and the user equipment, the base station does not send any data radio bearer configuration including network coding configuration.

[0037] In an embodiment, the method further comprises: before sending the data radio bearer configuration including the network coding configuration to the user equipment, receiving, by the base station, a status message from the user equipment.

[0038] In an embodiment, the status message comprises information related to the operational status of the user equipment.

[0039] In an embodiment, the network coding configuration comprises information related to network coding deactivation.

[0040] In an embodiment, the method further comprises: deactivating all or part of the radio link control entities previously used to send the packet according to the network coding.

[0041] In an embodiment, network coding deactivation is conditioned on monitoring of radio link quality status.

[0042] In an embodiment, the monitoring of the radio link quality status is performed by a base station.

[0043] In an embodiment, monitoring of the radio link quality status is performed by the user equipment, and the monitoring result is sent to the base station before network coding is deactivated.

[0044] In an embodiment, the method further comprises: upon receiving the network coding configuration including the information related to the network coding deactivation from the base station, the user equipment sends a confirmation message to the base station.

[0045] In an embodiment, the method further comprises: sending, by the base station, a message comprising information for notifying the user equipment of activation of the network coding configuration.

[0046] In an embodiment, information for notifying activation of the network coding configuration is embedded in the network coding configuration.

[0047] In an embodiment, the information for notifying activation of the network coding configuration includes information about a first data packet to be transmitted according to the network coding configuration.

[0048] In an embodiment, information for notifying activation of the network coding configuration is embedded in a data packet.

[0049] In an embodiment, information for notifying activation of the network coding configuration is embedded in a packet data convergence protocol header of a data packet.

[0050] In an embodiment, the method further comprises: sending, by the base station, information for notifying the user equipment of deactivation of the network coding configuration.

[0051] In an embodiment, information for notifying deactivation of the network coding configuration is embedded in the network coding configuration.

[0052] In an embodiment, the information for notifying deactivation of the network coding configuration includes information on a last data packet to be transmitted according to the network coding configuration.

[0053] In an embodiment, information for notifying deactivation of the network coding configuration is embedded in a data packet.

[0054] In an embodiment, information for notifying the deactivation of the network coding configuration is embedded in a packet data convergence protocol header of a data packet.

[0055] In an embodiment, the radio bearer configuration is sent to the user equipment via a radio resource control message.

[0056] In an embodiment, the confirmation message is sent via a radio resource control message.

[0057] In an embodiment, the message including the information for notifying the user equipment of the activation of the network coding configuration is transmitted through a radio resource control message.

[0058] In an embodiment, the message including the information for notifying the user equipment of the deactivation of the network coding configuration is transmitted through a radio resource control message.

[0059] According to another aspect of the present invention, a system for wireless communication between a base station and a user equipment is provided, wherein the base station and the user equipment include a processor, and the processor is configured to: send a data radio bearer configuration by the base station; and send packets between the base station and the user equipment according to the data radio bearer configuration; wherein: the data radio bearer configuration includes a network coding configuration; and the sent packets are sent according to the network coding configuration.

[0060] According to another aspect of the present invention, a computer program product for a programmable device is provided, the computer program product comprising an instruction sequence for implementing the method according to the present invention when the instruction sequence is loaded into and executed by the programmable device.

[0061] According to another aspect of the present invention, a computer-readable storage medium is provided, which stores instructions of a computer program for implementing the method according to the present invention.

[0062] According to another aspect of the present invention, a computer program is provided which, when executed, causes the method according to the present invention to be performed.

[0063] According to another aspect of the present invention, a base station device is provided for wireless communication between the base station and a user equipment, wherein the base station device includes a processor, and the processor is configured to: send a data radio bearer configuration to the user equipment; and exchange packets with the user equipment according to the data radio bearer configuration; wherein: the data radio bearer configuration includes a network coding configuration; and the exchanged packets are sent according to the network coding configuration.

[0064] According to another aspect of the present invention, a user equipment device is provided for wireless communication between a base station and a user equipment, wherein the user equipment device includes a processor, and the processor is configured to: receive a data radio bearer configuration from the base station; and exchange packets with the base station according to the data radio bearer configuration; wherein: the data radio bearer configuration includes a network coding configuration; and the exchanged packets are sent according to the network coding configuration.

[0065] At least a portion of the method according to the invention may be computer-implemented. Thus, the invention may take the form of a fully hardware embodiment, a fully software embodiment (including firmware, resident software, microcode, etc.), or a combination of software and hardware embodiments, which may all be generally referred to herein as "circuits," "modules," or "systems." In addition, the invention may take the form of a computer program product embodied in any tangible medium of expression having a computer-usable program code embodied in the medium.

[0066] Since the present invention can be implemented in software, the present invention can be embodied as computer readable code for providing to a programmable device on any suitable carrier medium. Tangible non-transitory carrier media may include storage media such as floppy disks, CD-ROMs, hard disk drives, magnetic tape devices, or solid-state memory devices. Transient carrier media may include signals such as electric signals, electronic signals, optical signals, acoustic signals, magnetic signals, or electromagnetic signals (e.g., microwave or RF signals). BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Embodiments of the present invention will now be described, by way of example only, and with reference to the following drawings, in which:

[0068] Figure 1 A radio access network (RAN) topology utilizing carrier aggregation that enables operation of a network coding scheme is shown.

[0069] Figure 2 A Radio Access Network (RAN) topology utilizing dual connectivity enabling operation of a network coding scheme is shown.

[0070] Figure 3 An example of a network coding scheme utilizing operations on the transmitter side is shown.

[0071] Figure 4 Show the use of (in Figure 3 An example of a network coding scheme with operations on the receiver side following the encoding operations depicted in FIG.

[0072] Figure 5 A block diagram is shown supporting downlink or uplink transmission with carrier aggregation.

[0073] Figure 6 A block diagram is shown supporting downlink transmission with dual connectivity.

[0074] Figure 7 A block diagram is shown supporting uplink transmission with dual connectivity.

[0075] Figure 8 An example of a process flow supporting NC configuration and activation processing according to one embodiment of the present invention is shown.

[0076] Fig. 9 An example of a process flow supporting NC configuration and activation processing according to another embodiment of the present invention is shown.

[0077] Fig.10 An example of a process flow supporting NC-enabled synchronization according to one embodiment of the present invention is shown.

[0078] Fig.11An example of a process flow supporting NC deactivation processing according to one embodiment of the present invention is shown.

[0079] Fig.12 An example of a process flow supporting an NC deactivation process according to another embodiment of the present invention is shown.

[0080] Fig.13 An example of a processing flow supporting synchronization of NC deactivation according to one embodiment of the present invention is shown.

[0081] Fig.14 An example of a process flow supporting NC configuration and activation processing for downlink transmission according to another embodiment of the present invention is shown.

[0082] Fig.15 An example of a process flow supporting an NC deactivation process for downlink transmission according to another embodiment of the present invention is shown.

[0083] Fig.16 A block diagram of a device supporting network coding according to the present invention is shown.

[0084] Fig.17 A first block diagram of a communication manager supporting network coding according to the present invention is shown.

[0085] Fig.18 A block diagram of a UE supporting network coding is shown.

[0086] Fig.19 A block diagram of a base station supporting network coding is shown.

[0087] Fig. 20 A flow chart illustrating a method of supporting NC configuration determination and setup processing at a base station level is shown.

[0088] Fig.21 A flow chart illustrating a method of supporting NC configuration shared with UE at base station level is shown.

[0089] Fig. 22 A flowchart illustrating a method for a UE to support NC configuration settings according to an embodiment of the present invention is shown.

[0090] Fig.23 A flow chart illustrating a method for a base station to support network coding activation according to an embodiment of the present invention is shown.

[0091] Fig.24 A flow chart illustrating a method of supporting NC configuration determination, setup and activation processing at a base station level according to one embodiment of the present invention is shown.

[0092] Fig.25A flow chart illustrating a method for a base station to support network coding enabling according to an embodiment of the present invention is shown.

[0093] Fig.26 A flowchart illustrating a method for a UE to support NC configuration settings according to another embodiment of the present invention is shown.

[0094] Fig. 27 A flowchart illustrating a method for a base station to support network coding deactivation according to an embodiment of the present invention is shown.

[0095] Fig.28 A flowchart illustrating a method for a base station to support network coding deactivation according to another embodiment of the present invention is shown.

[0096] Fig.29 A flowchart illustrating a method for UE to support network coding deactivation according to an embodiment of the present invention is shown.

[0097] Fig.30 A flow chart illustrating a method of supporting NC configuration determination, setup and activation processing at a base station level according to one embodiment of the present invention is shown.

[0098] Fig.31 A flowchart illustrating a method for a UE to support NC configuration settings according to another embodiment of the present invention is shown.

[0099] Fig.32 A flowchart illustrating a method for a base station to support network coding deactivation according to another embodiment of the present invention is shown.

[0100] Fig.33 A flowchart illustrating a method for UE to support network coding deactivation according to another embodiment of the present invention is shown.

[0101] Fig.34 An example of a packet format at an interface between a PDCP layer and an RLC layer according to the present invention is shown. DETAILED DESCRIPTION

[0102] Figure 1 A radio access network (RAN) topology with carrier aggregation that enables operation of a network coding scheme is shown.

[0103] An example of a wireless communication system 100 is presented, such as a 5G NR (New Radio) network that can benefit from the present invention. The wireless communication system includes a user equipment (UE) 101 and a base station 102, which can communicate wirelessly with the UE. Several other UEs and other base stations not shown in the figure may also be part of the system. The wireless communication system may be a New Radio (NR) network, a Long Term Evolution (LTE) network, or an Advanced LTE (LTE-A) network. A base station may refer to, but is not limited to, a radio transceiver, an eNodeB (eNB), or a next generation Node B (gNB). UE 101 is able to communicate with any type of base station or a limited type of base stations through a radio access network (RAN).

[0104] The base station 102 is connected to a core network 103, which may be, for example, a 5G core (5GC) or an evolved packet core (EPC). The connection between the base station and the core network entity may be wired or wireless.

[0105] A carrier aggregation (CA) mechanism may be implemented allowing UE 101 and base station 102 to communicate simultaneously on two different component carrier frequencies denoted as f1 and f2. The radio cell defined by the coverage area of ​​f1 is called a primary cell, while f2 defines a secondary cell.

[0106] Carrier aggregation has been introduced in the 4G / LTE standard and enhanced in 5G NR. Other wireless communication standards (such as the latest WiFi generations) also rely on this mechanism. The first purpose of carrier aggregation is to increase the data rate per user by sending different data on multiple frequency blocks (also called component carriers). Carrier aggregation can be applied to downlink (DL) transmissions from the base station to the UE and uplink (UL) transmissions from the UE to the base station.

[0107] Another benefit of carrier aggregation is providing both time and frequency diversity to error correction schemes (such as packet replication or network coding).

[0108] According to the PDCP duplication method, data from core network 103 is sent by base station 102 to UE 101 in the form of protocol data units (PDUs) on one component carrier frequency f1, and copies of these PDUs are sent to UE 101 on different component carrier frequency f2 at the same time or at different times.

[0109] In the context of network coding, according to some embodiments of the present invention, a first set of linear combinations may be sent on f1, and a second set of linear combinations may be sent on f2. In some embodiments of the present invention, the transmission of the linear combinations does not rely on carrier aggregation, i.e., the linear combinations are sent on the same frequency, but not optimally, because the system loses frequency diversity.

[0110] Figure 2 A Radio Access Network (RAN) topology with dual connectivity enabling operation of a network coding scheme is shown.

[0111] The figure presents a wireless communication system 200, such as a 5G NR (New Radio) network, that can benefit from the present invention. The wireless communication system includes a user equipment (UE) 201 and two base stations 202-a and 202-b that can communicate wirelessly with the UE. Several other UEs not shown in the figure may also be part of the system. The wireless communication system may be a New Radio (NR) network, a Long Term Evolution (LTE) network, or an Advanced LTE (LTE-A) network. Each base station may refer to, but is not limited to, a radio transceiver, an eNodeB (eNB), or a next generation Node B (gNB). UE 102 is capable of communicating with any type of base station or with a limited type of base stations.

[0112] Base stations 202-a and 202-b are connected to a core network 203, which may be, for example, a 5G core (5GC) or an evolved packet core (EPC). The connection between the base station and the core network entity and the connection between the two base stations may be wired or wireless.

[0113] A dual connection (DC) mechanism may be implemented, where UE 201 and base station 202-a communicate directly using the f1 frequency band, and where UE 201 also communicates with base station 202-a via base station 202-b using the f2 frequency band. In this particular configuration, base station 202-a is referred to as a master node (MN), and the f1 frequency band defines a master cell group (MCG). Base station 202-b is referred to as a secondary node (SN), and the f2 frequency band defines a secondary cell group (SCG).

[0114] In some embodiments, the f1 frequency and the f2 frequency may be the same.

[0115] Similar to carrier aggregation (CA), 3GPP has introduced dual connectivity (DC) in the 4G / LTE standard and enhanced dual connectivity (DC) in 5G NR with the goal of increasing user throughput, providing mobility robustness, and supporting load balancing between base stations. This applies to both downlink (DL) and uplink (UL) transmissions.

[0116] Another benefit of DC is that it provides not only time and frequency diversity for error correction schemes (such as packet duplication or network coding), but also space diversity.

[0117] According to the PDCP duplication method, data from the core network 203 is sent directly to the UE 201 in the form of protocol data units (PDUs) by the base station 202-a via the MCG, and copies of these PDUs are sent by the base station 202-a to the base station 202-b, which forwards these PDUs to the UE 201 via the SCG. At the protocol level, it can be considered that each PDU is sent through a split data radio bearer (DRB) or a split bearer, where the same DRB is used on both the MCG and the SCG (actually split between the MCG and the SCG).

[0118] Similarly, in the context of network coding, according to some embodiments of the present invention, a first set of linear combinations is sent directly by base station 202-a to UE 201, while a second set of linear combinations is sent by base station 202-a to UE 201 via base station 202-b.

[0119] Figure 1 and Figure 2 Two possible communication channels (also called branches) between a base station and a UE are shown. However, those skilled in the art know that the 5G NR specification does not limit CA and DC to two branches. More branches can be obtained by adding other component carriers in CA, or by adding secondary base stations in DC. As a generalization, a multi-connection scheme involving multiple additional base stations can be established between the UE and the base station. Details on carrier aggregation (CA) and dual connectivity (DC) are available in specification documents TS 38.300 and TS 37.340.

[0120] Figure 3 An example of a network coding scheme with transmitter-side operation is shown.

[0121] An example of a network coding scheme focusing on the encoding aspects of network coding to be performed by the NC encoder module 300 is presented. An incoming PDU is first processed by a padding function 310. If the length of the incoming PDU is odd, one byte of dummy data (e.g., all zeros) is appended to the PDU, and a padding indication is set to the input of a transmission buffer 308 that is also responsible for header processing. The PDU is then processed by a PDU splitter 301, which splits the PDU into two parts.

[0122] The splitting can be done in many different ways. One way to do the splitting action is to split the PDU into two parts of equal size: (PDU_length / 2) The first byte is placed in the so-called even packet (also called EVEN PDU or EVEN), while the subsequent bytes are aggregated in the so-called odd packet (also called ODD PDU or ODD). As an example of other implementations, 1 byte of every 2 bytes can be ordered and placed in the EVEN PDU and the ODD PDU. Those skilled in the art can consider other splitting schemes.

[0123] The two parts are stored in buffer 302 for EVEN PDU and in buffer 303 for ODD PDU. Splitting the PDU into two parts is beneficial because reducing the length of the transmitted packet reduces the probability that a bit is damaged during transmission. Therefore, this also reduces the need for retransmissions due to receiving damaged packets.

[0124] Via the transmission buffer 308, four PDUs will be output: EVEN, ODD, and two PDUs resulting from the combination of EVEN and ODD. The first combined packet, referred to as COMB1 and stored in the buffer 306, is a sum (performed by the multiplication and addition unit 304) of two different coefficients α with the bytes in ODD and EVEN. 11 and α 12 The second combined packet, referred to as COMB2 and stored in buffer 307, is a sum (performed by multiplication and addition unit 305) of two different coefficients α with the bytes in ODD and EVEN. 21 and α 22 The result of the byte-to-byte multiplication is produced by the byte-to-byte addition.

[0125] In some (but not limiting) embodiments of the present invention, operations are performed in a Galois Field GF256. Not all sets of 4 coefficients in GF 256 can be used. Multiple 1s and 0s must be excluded because they will leave the original data unchanged, and (α 11 ×α 12 ) should not be equal to (α 21 ×α 22 ), otherwise the linear combinations will be identical.

[0126] Sequence numbers may also be allocated in the transmission buffer 308. Such sequence numbers may be in the format of (4n+t), where t belongs to {0, 1, 2, 3}. For example, the sequence number of any ODD PDU will be in the form of 4n(t=0), the sequence number of any EVEN PDU will be in the form of (4n+1), the sequence number of any COMB1 PDU will be in the form of (4n+2), and the sequence number of any COMB2 PDU will be in the form of (4n+3).

[0127] Finally, four coded PDUs (ie, ODD, EVEN, COMB1 and COMB2) are sent on different branches (see also Figure 1 and Figure 2 ). For example, ODD and COMB1 are sent on the first branch, while EVEN and COMB2 are sent on the second branch.

[0128] Figure 4 Shown with Figure 3 The encoding operations depicted in the figure correspond to an example of a network coding scheme for operations on the receiver side.

[0129] This example focuses on the decoding aspects of network coding to be performed by the NC decoder module 400 .

[0130] Each received coded PDU (ODD, EVEN, COMB1 or COMB2) enters the receive buffer 411. The padding indication associated with the received PDU can be extracted and passed to the padding removal function 409. In the receive buffer 411, the received PDUs can be reordered according to their sequence numbers. Any sequence number divided by 4 produces a quotient n and a remainder r. Any two PDUs sharing the same quotient n (i.e., any two of EVEN, ODD, COMB1 and COMB2) are sufficient to reconstruct the original PDU. Based on the remainders calculated in modules 401 and 402 of any two received PDUs, a specific set of 4 coefficients (b 11 , b 12 , b 21 and b 22 ) to reconstruct the packet. Example: If ODD and EVEN are received, the coefficients will be the identity matrix (b 11 =1, b 12 =0, b 21 = 0 and b 22 =1).

[0131] Therefore, the remainder of module 401 (also referred to as Rem(SN1)) and the remainder of module 402 (also referred to as Rem(SN2)) of any pair of received PDUs are inputs to the lookup table 403.

[0132] Description in lookup table 403:

[0133] The bytes of the two received coded PDUs (byte (SN1, x) and byte (SN2, x) respectively) will form the vector x indicates the position of the byte in the packet. This vector will be multiplied by the matrix M, and the result is the 2 parts corresponding to the original PDU. Usually 6 cases occur:

[0134] - Case 1) EVEN is received, ODD is received. Rem(SN1)=0 and Rem(SN2)=3. Therefore, the matrix M is the identity matrix;

[0135] - Case 2) EVEN is received, COMB1 is received. Rem(SN1)=0 and Rem(SN2)=1, the matrix M is The inverse of α 1,1 and α 1,2 are the coefficients used by the encoding engine 303 of the transmitter, such as Figure 3 as described in;

[0136] -Case 3) EVEN is received, COMB2 is received. Rem(SN1)=0 and Rem(SN2)=2, the matrix M is The inverse of α 2,1 and α 2,2 are the coefficients used by the encoding engine 303;

[0137] -Case 4) ODD is received, COMB1 is received. Rem(SN1)=1 and Rem(SN2)=3, the matrix M is The inverse of α 1,1 and α 1,2 are the coefficients used by the encoding engine 303;

[0138] - Fifth case) ODD is received, COMB2 is received. Rem(SN1)=2 and Rem(SN2)=3, the matrix M is The inverse of α 2,1 and α 2,2 are the coefficients used by the encoding engine 303;

[0139] -Sixth case) COMB1 is received, COMB2 is received. Rem(SN1)=1 and Rem(SN2)=2, the matrix M is The inverse of α 1,1 , α 1,2 , α 2,1 and α2,2 are the coefficients used by the encoding engine 303 .

[0140] Although the probability of subsequent events is very low, it may happen that only one of the 4 possible coded PDUs is received. In this case, the process will not retrieve the missing original PDU (or may request a retransmission).

[0141] The matrix is ​​given as a preferred choice because the decoding complexity is reduced due to the use of coefficients belonging to the set {0,1}. However, any choice of 4 pairs of linearly independent vectors is acceptable. The matrix operations are performed by "multiplication and addition" units 404 and 405. The results are stored in buffers 406 and 407 before being appended by module 408 to reconstruct the original PDU. The extra padding can be removed in module 409. Finally, module 410 removes duplicated PDUs because it may happen that more than 2 coded PDUs sharing the same quotient are received.

[0142] Figure 5 A block diagram illustrating a protocol stack used in downlink or uplink transmission with carrier aggregation is shown.

[0143] A wireless communication system may be a packet-oriented network that operates using one protocol layer stacked on top of another. In the case of the present invention, the protocols for exchanging control packets and data packets are independent, which means that there is a control plane independent of the user data plane. The two planes use the same layers but different stacks. The user data plane may consist of an SDAP layer, a PDCP layer, an RLC layer, and a MAC layer. The control data plane may consist of an RRC layer, a PDCP layer, an RLC layer, and a MAC layer. Figure 5 Represents the protocol stack responsible for user data packets. The stack consists of the SDAP layer 511, PDCP layer 512, RLC layers 513 and 514, MAC layer 515, and PHY layer 516 on the transmitter side 510. On the receiver side 520, the same stack is found to handle incoming data packets in reverse order. First comes the PHY layer 526, then the MAC layer 525, RLC layers 523 and 524, PCDP layer 522, and finally the SDAP layer 521. The PHY layer 516 at the transmitter side provides an electrical interface to the transmission medium (air) by converting the information stream into a physical modulated signal, modulating the carrier frequency, and performs the opposite operation at the receiver side 526, providing an interface from the medium to the electrical signal by demodulating and down-shifting. The PHY layer is described in TS 38.201, TS 38.211, TS 38.212, TS 38.213, TS 38.214.

[0144] The MAC (Medium Access Channel) 516 protocol is responsible for selecting an available transport format for user data and for mapping logical channels to transport channels. The MAC also handles part of the hybrid automatic repeat request scheme. The MAC layer is described in TS 38.321. The MAC encapsulates data packets sent from the RLC layers 513 and 514. The MAC adds a header that carries the information required for the MAC functionality.

[0145] The MAC on the receiver side 525 receives the data from the PHY layer 526 and removes the MAC header. The MAC passes the data to the RLC layer.

[0146] The RLC (Radio Link Control) layer 513 or 514 is responsible for segmenting the user data packets sent from the PDCP layer so that they are suitable for the transmission format selected by the MAC. The RLC layer can add headers that carry information required for the RLC function. If a mode other than the transparent transmission mode is selected, the RLC layer is also responsible for requesting retransmission of lost packets. It must be noted that these requests are made through ACK / NACK signaling and the buffer status request (BSR) sent backward. The ACK / NACK indicates which packets have been received or not received, and the buffer status in the response to the BSR indicates which packets will still be successfully sent and received. The RLC layer is described in TS38.322. There are as many RLC layer instantiations as carrier frequencies (also called component carriers). In carrier aggregation, the RLC layer delivers or receives their egress / ingress packets to only one MAC entity.

[0147] The RLC layers 523 and 524 on the receiver side receive data from the MAC layer. The RLC layer manages the creation of ACK / NACK packets required for retransmissions. Due to different propagation, the carrier frequencies can present different transmission qualities, so it is necessary to have multiple RLCs because the modulation and retransmissions may be different. The RLC on the receiver side also handles segmentation and recreates the PDCP PDU before passing it to the PDCP layer.

[0148] The Packet Data Convergence Protocol (PDCP) layer 512 (Tx) / 522 (Rx) handles IP header compression / decompression, encryption / decryption, and integrity of user data packets as control packets pass through, but enforces packet numbering on the transmitter side and reordering of received packets on the receiver side. The PDCP layer is described in TS 38.323. PDCP encapsulates (when placed on the transmission path) / decapsulates (when placed on the reception path) user data packets sent from or to the above SDAP layer or control packets sent from or to the RRC layer. Adds / removes headers carrying information required for PDCP functions, including sequence numbers, control / data identification bits, and PDU type information when the control bit is set. PDCP can deliver or receive its egress / ingress packets to multiple RLC layer entities in multi-connection mode (carrier aggregation / multi-connection with up to four branches).

[0149] The SDAP (Service Data Adaptation Protocol) layer 511 or 521 handles quality of service. The SDAP layer is described in TS 38.324. This layer is present only in the user data plane of 5G NR. QoS in 5G NR is flow-based. Packets are classified and marked with QoS flow identifiers (QFI). 5G QoS flows are mapped to data radio bearers (DRBs) in the RAN. In 5G NR, a radio bearer or data radio bearer corresponds to the use of resources of the implementation protocol (PDCP, RLC, MAC) and PHY layers. A data radio bearer can carry several data flows if the data flows belong to the same QoS class. The role of the SDAP layer is to attribute radio bearers to one or more QoS flows.

[0150] In carrier aggregation, user data is sent on 2 or more component carriers, represented here by 540 and 541. The component carriers have different frequencies and may have different bandwidths, different propagation, and thus different throughputs. As mentioned above, managing these differences requires several RLC layers. However, the same MAC layer handles the transport streams.

[0151] Figure 6 A block diagram illustrating a protocol stack for downlink transmission with dual connectivity is shown.

[0152] A first base station 610 (primary) including an SDAP layer 611, a PDCP layer 612, an RLC layer 613, a MAC layer 615, and a PHY layer 616 operates a first protocol stack in transmission. The base station may belong to a 4G / LTE network or a 5G NR network. A second base station 630 (secondary) belonging to a 5G NR network includes an RLC layer 633, a MAC layer 635, and a PHY layer 636. The RLC layers 613 and 633 obtain their PDUs from the same PDCP layer 613, thereby forming a so-called split bearer.

[0153] In UE 620, handling received packets requires duplication of some functions, so 2 separate partial stacks are used. The first partial stack includes PHY layer 628, MAC layer 627 and RLC layer 623. The second partial stack includes PHY layer 626, MAC layer 625 and RLC layer 624. The 2 RLC layers 623 and 624 pass their PDUs to the same PDCP layer 622. The PDCP layer 622 will be responsible for removing duplicate packets before passing them to SDAP layer 621.

[0154] In case more than two branches are used (multiple connection mode), there are as many partial stacks (PHY, MAC, RLC) as the number of branches.

[0155] Figure 7 A block diagram illustrating a protocol stack for uplink transmission with dual connectivity is shown.

[0156] The first base station 710 including the SDAP layer 711, the PDCP layer 712, the RLC layer 713, the MAC layer 715 and the PHY layer 716 operates the first protocol stack in reception. The base station may belong to a 4G / LTE network or a 5G NR network. The second base station 730 belonging to the 5G NR network includes an RLC layer 733, a MAC layer 735 and a PHY layer 736. The RLC layers 713 and 733 send their PDUs to the same PDCP layer 712. The PDCP layer 712 will be responsible for removing duplicate packets before passing them to the SDAP layer 711.

[0157] In UE 720, handling packets to be sent requires duplication of some functions, so 2 separate partial stacks are used. The first partial stack includes PHY layer 728, MAC layer 727 and RLC layer 723. The second partial stack includes PHY layer 726, MAC layer 725 and RLC layer 724. The 2 RLC layers 723 and 724 receive their PDUs from the same PDCP layer 722, thus forming a so-called split bearer.

[0158] In case more than two legs are used (multiple connection mode), there are as many partial stacks (PHY, MAC, RLC) as the number of legs.

[0159] Figure 8 An example of a process flow 800 is shown to support NC configuration and activation processing according to one embodiment of the present invention.

[0160] Assume that UE 801 is in an RRC connected state as defined in TS 38.331, which means that UE 801 is connected to base station 802 (which can be a gNB in ​​a 5G NR network). A signaling radio bearer is established between base station 802 and UE 801. UE 801 is also registered in a core network entity not shown in the figure.

[0161] According to one embodiment of the present invention, UE 801 refers to Figure 1 UE 101 or Figure 2 UE 201, and base station 802 refers to Figure 1 Base station 102 or Figure 2 base station 202-a or 202-b.

[0162] At some point, base station 802 may need to configure and enable an NC scheme for transmitting a data flow to UE 801 (downlink) or from UE 801 (uplink). This action may be triggered, for example, by a Quality of Service (QoS) level associated with the data flow.

[0163] According to one embodiment of the present invention, if the QoS level corresponds to high reliability and low delay requirements (such as URLLC), network coding is applied once both the base station 802 and the UE 801 support network coding.

[0164] In another embodiment of the present invention, the requirement for NC may be triggered by information received in a message 803 from UE 801. For example, UE 801 may report poor communication quality (due to fading or interference), and therefore UE 801 may (implicitly or explicitly) request the use of NC. In one embodiment of the present invention, message 803 is a radio resource control (RRC) message MesurementReport described in TS 38.331 (version 16.0.0). Alternatively, the message may be an RRC message FailureInformation also described in TS 38.331. At step 804, base station 802 decides to consider the use of NC based on the above elements.

[0165] If a data radio bearer already exists and meets the required QoS level, the data flow is sent on this DRB. Otherwise, a new DRB needs to be established and some verification is performed by the base station 802 at step 805. First, the base station itself should support NC. This is verified by reading base station internal parameters, which indicate the supported NC configurations including NC schemes if several NC configurations are specified.

[0166] In addition, the base station 802 needs to check whether the UE 802 supports NC and which NC schemes the UE supports. These elements may already be known to the base station, which information elements usually come from a previous message exchange with the UE for establishing a connection, or these information elements may be retrieved from the UE 801 through a message exchange about the UE capabilities. In addition, the base station 802 may check which transmission mode (carrier aggregation or dual / multiple connections) is feasible for setting up network coding communications with the UE. The above elements related to the NC support of the UE and the associated NC schemes may also be checked by reading parameters stored in a memory or through dedicated messages exchanged with the UE.

[0167] In case the use of NC is feasible, the base station 802 determines the NC configuration at step 806. In one embodiment of the present invention, this means that the base station 802 selects the NC scheme, the transmission mode for NC (i.e., transmission via CA or DC...), the number of associated transmission branches to be used (i.e., RLC layers), the number of linear combinations to be generated and the coefficients to be used, and the mapping of each linear combination to the selected branches. For example, DC is the preferred mode (for spatial diversity) in the case of 2 branches (for low complexity), the selected NC scheme is the first in a predefined list of several NC schemes supported by both the base station 802 and the UE 801, and the number of linear combinations is a function of the requested QoS level and the current quality of the radio link.

[0168] In one embodiment of the present invention, all or part of the above configuration parameters may be considered. The list of these parameters is non-limiting, and other configuration parameters may be considered.

[0169] In step 807, the transmission mode (CA, DC ...) is set according to the previous decision made in step 804. In one embodiment of the invention, this step may be skipped if the selected transmission mode is already active. In another embodiment of the invention, this step includes configuring the transmission mode according to the relevant 3GPP standards. Figure 5 , Figure 6 and Figure 7 In the case of multiple connections, the addition of one or more secondary base stations should be performed by the base station 802 (as a primary node) that can become the primary node. Figure 2The procedure for adding a secondary node is described in 3GPP document TR 37.340 (Section 10.2 in Version 16.1.0).

[0170] Four steps 804, 805, 806 and 807 define the NC configuration process. To simplify the description of the other figures, these steps are collected in a single step called NC configuration process 808.

[0171] Then, all or part of the NC configuration parameters should be sent to the UE 801 using an NC configuration request message 809. In one embodiment of the present invention, the NC configuration request message 809 is sent via a radio resource control (RRC) message 809RRCReconfiguration, which is defined in TS38.331 (version 16.0.0) for the RRC protocol in the control plane and modified for the purpose of the present invention, where, for example, a field related to the NC configuration is added in one of the information elements carried in the message. The message includes a command sent by the base station 802 to the UE 801 to apply the NC configuration for the data stream. The NC configuration parameters may include, but are not limited to, an indication of the NC scheme used, an indication of the coefficients used to generate each linear combination, and an indication of the branches used to send each combination. The message also carries information that enables the UE 801 to set the transmission mode (CA, DC) using the number of branches used.

[0172] In response to the message 809, the UE 801 confirms with an NC Configuration Complete message 810, which in one embodiment of the invention may be the RRC message RRCReconfigurationComplete as defined in TS 38.331.

[0173] Then, the UE 801 configures its NC encoding engine 1724 (for uplink transmission) or NC decoding engine 1725 (for downlink transmission) to be ready to apply the selected NC scheme. In the case of uplink transmission, the UE 801 can start encoding the packets to be sent according to the selected NC scheme. In the case of downlink transmission, the UE 801 will decode the received packets according to the selected NC scheme.

[0174] In base station 802, reception of message 810 indicates that the UE is ready to apply NC. At step 812, base station 802 enables NC: in case of downlink transmission, base station 802 can start encoding packets to be sent, and in case of uplink transmission, base station 802 will decode received packets according to the agreed NC configuration.

[0175] At step 811, UE 801 enables NC, ie, in case of uplink transmission, UE 801 starts encoding packets to be sent, and in case of downlink transmission, UE 801 will decode received packets according to the agreed NC configuration.

[0176] Fig. 9 An example of a process flow 900 is shown to support NC configuration and activation processing according to another embodiment of the present invention.

[0177] Assume that UE 901 is in an RRC connected state as defined in TS 38.331, which means that UE 901 is connected to base station 902, which is a gNB in ​​a 5G NR network in the context of the figure. A signaling radio bearer is established between base station 902 and UE 901. UE 901 is also registered in a core network entity not shown in the figure.

[0178] According to one embodiment of the present invention, UE 901 refers to Figure 1 UE 101 or Figure 2 UE 201, and base station 902 refers to Figure 1 Base station 102 or Figure 2 base station 202-a or 202-b.

[0179] After a certain time of inactivity (no transmission or reception of data) in UE 901, base station 902 may send an RRC message 903 called RRCRelease to UE 901 with a suspension configuration as described in TS 38.331. The purpose may be to reduce power consumption in UE 901 and / or save some radio bandwidth. Upon receiving this message 903, UE 901 stores the current configuration, which may include reference Figure 8 The base station 902 also stores the current configuration, which may also include a reference to the network coding configuration that may have been previously agreed upon, and transitions to an RRC state called RRC Inactive. Figure 8 A network coding configuration may have been previously agreed upon.

[0180] At some point, the base station 902 may have new data to send to the UE 901, and the base station 902 initiates a paging procedure to inform the UE (messages not shown in the figure). Alternatively, the UE 901 may have new data to send, and therefore must request the base station 902 to restore the connection. In both cases, the UE 901 sends an RRC message 904 called RRCResumeRequest as defined in TS 38.331.

[0181] Upon receiving message 904, base station 902 will restore the connection. In this case, base station 902 may consider enabling network coding associated with the communication for the communication, and may therefore apply NC configuration process 908, which is similar to NC configuration process 808 (see also Figure 8 ) is the same. The base station 902 then sends an RRC message 905 called RRCResume and defined in TS38.331 to the UE 901. The message may include the new configuration of the radio bearer. For the NC configuration request message 809, the RRCReconfiguration information 905 may be modified with the same additional fields regarding the NC configuration.

[0182] Upon receiving message 905, UE 901 returns to state RRC connected. In addition, in step 911, UE 901 configures its NC encoding engine (for uplink transmission) or NC decoding engine (for downlink transmission) according to the content of message 905 (new configuration or previous configuration). When the NC scheme will be applied to uplink transmission, UE 901 can start encoding the packets to be sent according to the selected NC configuration. In the case of downlink transmission, UE 901 will decode the received packets according to the selected NC configuration.

[0183] At step 912, the base station 902 enables NC (if needed). In the case of downlink transmission, the base station 902 may start encoding packets to be sent, and in the case of uplink transmission, the base station 902 will decode received packets according to the selected NC scheme.

[0184] At step 911, the UE 901 enables NC, ie, in case of uplink transmission, the UE 901 starts encoding packets to be sent, and in case of downlink transmission, the UE 901 will decode received packets according to the selected NC configuration.

[0185] Fig.10 FIG. 1000 is an example of a process flow 1000 for supporting NC-enabled synchronization according to an embodiment of the present invention. UE 1001 may be a user entering Figure 8 Step 811 of the NC-enabled UE 801, or the UE 1001 may be entered Fig. 9 The step 911 is for the NC enabled UE 901. The base station 1002 may be entered Figure 8 Step 812 of the present invention is for the NC-enabled base station 802, or the base station 1002 may be entered Fig. 9 In step 912, the base station 902 is used for NC activation.

[0186] In reference Figures 8 to 15 Any of the other embodiments of the present invention may also be considered to apply Fig.10 Other situations of synchronized methods.

[0187] When NC is enabled for an existing radio bearer with an already transmitted data stream, the data packets will become NC encoded. The receiver of these packets needs to understand when the packets are NC encoded. Although the receiver knows that NC will be applied, it may still receive some packets that have not yet been NC encoded because these packets were already in the transmitter's transmission queue when the decision to apply network coding was made. In one embodiment of the present invention, in order to synchronize the start of NC between the transmitter and the receiver, an indication as to whether NC encoding is applied is inserted in the header of the transmitted packet. In one embodiment of the present invention, the indication is inserted in a header handled by the layer that performs NC encoding and decoding. In one embodiment of the present invention, the layer that performs NC encoding and NC decoding is the PDCP layer as defined by 3GPP in TS 38.323.

[0188] Therefore, for uplink transmission, when UE 1001 enables NC in step 1011, UE 1001 encodes the packet with the NC notification inserted in the header. The uplink data packet 1013 is sent to the base station 1002, and the base station 1002 parses the header of each received packet. When the packet is identified as NC encoded, the base station 1002 enables the NC decoding engine 1725 in step 1012.

[0189] For downlink transmission, when the base station 1002 enables NC in step 1022, the base station 1002 encodes the packet with the NC notification inserted in the header. The downlink data packet 1023 is sent to the UE 1001, and the UE 1001 parses the header. When the packet is identified as NC-encoded, the UE 1001 enables the NC decoding engine 1725 in step 1021.

[0190] Fig.11 An example of a process flow 1100 to support NC deactivation processing according to one embodiment of the present invention is shown.

[0191] It is assumed that UE 1101 is in an RRC connected state as defined in TS 38.331, which means that UE 1101 is connected to base station 1102 (which can be a gNB in ​​a 5G NR network). It is also assumed that at least one uplink or downlink data radio bearer (DRB) using an active NC scheme has been established between base station 1102 and UE 1101.

[0192] According to one embodiment of the present invention, UE 1101 refers to Figure 1 UE 101 or Figure 2UE 201, and base station 1102 refers to Figure 1 Base station 102 or Figure 2 base station 202-a or 202-b.

[0193] At some point, the base station 1102 may consider deactivating the NC currently in operation for the DRB in step 1105. In one embodiment of the present invention, the action is triggered by detecting an improvement in the quality of the radio link with the UE 1101 (for uplink transmission). In another embodiment of the present invention, the action may be triggered by information received in a message status report 1104 from the UE 1101. For example, the UE 1101 may report an improvement in the quality of communication with the base station 1102, and therefore the UE 1101 may (implicitly or explicitly) request the deactivation of the NC. In one embodiment of the present invention, the status report message 1104 is a radio resource control (RRC) message MeasurementReport described in TS 38.331 (version 16.0.0). In another embodiment of the present invention, the status report message 1104 may be an RRC message FailureInformation also described in TS 38.331.

[0194] In addition, in the case of multiple connections, UE 1101 can report the degradation of the radio link quality with the secondary base station through, for example, the RRC message SCGFailureInformation described in TS 38.331. Then, the current NC configuration in the case of multiple connections needs to be stopped, and a new NC configuration that is more suitable for the new situation may be enabled. Alternatively, UE 1101 can report that it cannot continue to process NC due to low battery power, high processing load or high temperature. This situation can be reported through an RRC message called UEAssistanceInformation described in TS 38.331.

[0195] To deactivate NC, the base station 1102 may perform step 1106 to deactivate the transmission modes (carrier aggregation, dual / multi connectivity) that will no longer be needed when NC is no longer used. This step includes reconfiguring Figure 5 , Figure 6 or Figure 7 The layers described in .

[0196] Then, the base station 1102 sends an NC configuration request message 1109 to the UE 1101. In one embodiment of the present invention, the message 1109 is RRCReconfiguration defined in TS 38.331 and is modified for the purpose of the present invention to include a command to deactivate the NC.

[0197] In another embodiment of the present invention, message 1109 informs UE 1101 to deactivate the transmission mode (CA, DC...) for NC.

[0198] In response to message 1109, UE 1101 confirms request message 1109 by sending NC configuration complete message 1110. In one embodiment of the present invention, NC configuration complete message 1110 may be RRC message 1110RRCReconfigurationComplete as defined in TS 38.331.

[0199] Then, in step 1111, UE 1101 configures its NC encoding engine 1724 (for uplink transmission) or NC decoding engine 1725 (for downlink transmission) to stop NC operation for the relevant DRB.

[0200] In base station 1102, the receipt of message 1110 indicates that UE 1101 is stopping NC operation for the relevant DRB. At step 1112, base station 1102 configures its NC encoding engine 1724 or NC decoding engine 1725 accordingly.

[0201] Fig.12 An example of a process flow 1200 for supporting NC deactivation processing according to another embodiment of the present invention is shown. It is assumed that UE 1201 is in an RRC connected state as defined in TS 38.331, which means that UE 1201 is connected to base station 1202, which is a gNB in ​​a 5G NR network in the context of the figure. It is also assumed that at least one uplink or downlink data radio bearer (DRB) using an active NC scheme has been previously established between base station 1202 and UE 1201.

[0202] According to one embodiment of the present invention, UE 1201 refers to Figure 1 UE 101 or Figure 2 UE 201, and base station 1202 refers to Figure 1 Base station 102 or Figure 2 base station 202-a or 202-b.

[0203] After a certain period of time when UE 1201 is inactive (no transmission or reception of data), base station 1202 may send an RRC message 1203 called RRCRelease to UE 1201 with a suspension configuration as described in TS 38.331. The purpose may be to reduce power consumption in UE 1201 and / or save some radio bandwidth. Upon receiving this message 1203, UE 1201 stores the current configuration and transitions to an RRC state called RRC inactive. Base station 1202 also stores the current configuration.

[0204] At some point, the base station 1202 may have new data to send to the UE 1201, and the base station 1202 initiates a paging procedure to inform the UE (messages not shown in the figure). Alternatively, the UE 1201 may have new data to send, so the UE 1201 must request the base station 1202 to restore the connection. In both cases, the UE 1201 sends an RRC message 1204 called RRCResumeRequest as defined in TS 38.331.

[0205] Upon receiving message 1204, base station 1202 will restore the connection. In this case, base station 1202 may consider deactivating the network coding previously applied to the data radio bearer (DRB) for the given data flow. To this end, steps 1205 and 1206 are performed. Step 1205 and Fig.11 The same as step 1105 , and step 1206 is the same as step 1106 .

[0206] The base station 1202 then sends an RRC message 1207 called RRCResume as defined in TS 38.331 to the UE 1201. The message may include the new configuration of the radio bearers. Fig.11 In message 1109RRCReconfiguration, RRCResume message 1207 is modified with the same command to deactivate NC.

[0207] Upon receiving message 1207, UE 1201 returns to state RRC CONNECTED. Furthermore, at step 1211, UE 1201 configures its NC coding engine (for uplink transmission) or NC decoding engine (for downlink transmission) to stop NC operation for the data radio bearer concerned.

[0208] At step 1212, the base station 1202 configures its NC encoding engine or NC decoding engine accordingly to stop the NC operation for the DRB involved.

[0209] Fig.13 FIG. 1300 shows an example of a synchronous process flow 1300 for supporting NC deactivation according to an embodiment of the present invention. UE 1301 may be a user entering Fig.11 Step 1111 of UE 1101 for NC deactivation, or UE 1301 may be entered Fig.12 The step 1211 is for UE 1201 to deactivate NC. The base station 1302 may be Fig.11 In step 1112, the base station 1102 is used for NC deactivation, or the base station 1302 may be entered Fig.12 In step 1212 , the base station 1202 is used for NC activation.

[0210] In reference Figures 8 to 15 Any of the other embodiments of the present invention may also be considered to apply Fig.13 Other situations of synchronized methods.

[0211] When NC is deactivated for an existing radio bearer utilizing a data stream being sent, data packets will no longer be NC encoded. The receiver of these packets needs to understand when packets are no longer NC encoded. Although the receiver is aware that NC will be stopped, some packets that are NC encoded may still be received because they were already present in the transmitter's transmission queue when the decision to stop network coding was made. In order to synchronize the stopping of NC between the transmitter and the receiver, an indication of whether NC is applied is inserted in the header of the sent packet. Preferably, the indication is inserted in a header handled by the layer that performs NC encoding and decoding. In one embodiment of the present invention, as defined by 3GPP in TS 38.323, the layer that performs NC encoding and decoding is the PDCP layer.

[0212] Therefore, for uplink transmission, when UE 1301 deactivates NC in step 1311, UE 1301 stops encoding packets with NC deactivation notification inserted in the header. Uplink data packets 1313 are sent to base station 1302, and base station 1302 parses the header of each received packet. When the packet is identified as not NC encoded, base station 1302 deactivates NC decoding engine 1725 in step 1312.

[0213] For downlink transmission, when the base station 1302 deactivates NC in step 1322, the base station 1302 stops encoding the packet with the NC deactivation notification inserted in the header. The downlink data packet 1323 is sent to the UE 1301, and the UE 1301 parses the header. When the packet is identified as not NC-encoded, as described below with reference to Fig.17 As described above, UE 1301 deactivates NC decoding engine 1725 in step 1321 .

[0214] Fig.14 An example of a process flow 1400 is shown to support NC configuration and activation processing for downlink transmissions according to another embodiment of the present invention.

[0215] Assume that UE 1401 is in an RRC connected state as defined in TS 38.331, which means that UE 1401 is connected to base station 1402 (which can be a gNB in ​​a 5G NR network). UE 1401 is also registered in a core network entity not shown in the figure.

[0216] According to one embodiment of the present invention, UE 1401 refers to Figure 1 UE 101 or Figure 2 UE 201, and base station 1402 refers to Figure 1 Base station 102 or Figure 2 base station 202-a or 202-b.

[0217] At some point, base station 1402 may need to configure and enable the NC scheme for downlink transmission of data flows to UE 1401. In one embodiment of the invention, this decision may be triggered by a QoS level associated with the data flow, or in another embodiment of the invention, by receiving a status report message 1403 from UE 1401. Message 1403 may be Figure 8 Then, at step 1408, base station 1402 applies the message 803 described in Figure 8 The NC configuration process described at step 808 in .

[0218] In case that configuration of the data radio bearer is required, for example if the CA or DC transmission mode is deactivated, the base station 1402 sends an RRC message RRCReconfiguration as defined in TS 38.331 to the UE 1401. In response to the message (the RRCReconfiguration message), the UE 1401 sends an RRC message RRCReconfigurationComplete as defined in TS 38.331 to the base station 1402.

[0219] Then, the NC configuration (or part thereof) should be sent to the UE 1401. Here this is achieved by inserting NC configuration parameters in a specific NC header attached to at least one network coding packet. This means that the base station 1402 enables the NC function by enabling its NC coding engine 1724 for the data stream at step 1412, and at least one of the downlink data packets 1409 sent to the UE 1401 will include an NC header. In one embodiment of the present invention, the NC header is an extension of the packet header handled by the layer that performs NC encoding and decoding. In one embodiment of the present invention, the layer that performs NC encoding and NC decoding is the PDCP layer. The traditional header should be modified to include a notification that the packet is NC encoded, and therefore includes an NC header. The NC configuration parameters embedded in the NC header include indications related to the NC scheme used and indications related to the coefficients used to encode the packet. In one embodiment of the present invention, all or part of the above configuration parameters may be considered. The list of these parameters is non-limiting, and other configuration parameters may be considered.

[0220] When receiving downlink data packets 1409, UE 1401 will parse the headers of each received packet, including the specific NC header, to retrieve the NC configuration and be able to decode the received NC coded packets. When an NC coded packet is detected, UE 1401 configures and enables its NC decoding engine 1725 according to the retrieved NC configuration at step 1411.

[0221] In another embodiment, the first part of the network coding configuration is provided by the base station, for example, via a Figure 8 The second part of the configuration is embedded in the NC header attached to at least one of the network coding packets.

[0222] Fig.15 An example of a process flow 1500 supporting NC deactivation processing for downlink transmissions according to another embodiment of the present invention is shown.

[0223] It is assumed that UE 1501 is in an RRC connected state as defined in TS 38.331, which means that UE 1501 is connected to base station 1502 (which can be a gNB in ​​a 5G NR network). It is also assumed that at least one downlink data radio bearer (DRB) using an active NC scheme is established between base station 1502 and UE 1501.

[0224] According to one embodiment of the present invention, UE 1501 refers to Figure 1 UE 101 or Figure 2 UE 201, and base station 1502 refers to Figure 1 Base station 102 or Figure 2 base station 202-a or 202-b.

[0225] At some point, the base station 1502 may consider deactivating the NC currently in operation for the DRB in step 1505. This action may be triggered by detecting an improvement in the quality of the radio link with the UE 1501, for example, using information received in a status report message 1503 from the UE 1501. For example, the UE 1501 may report an improvement in the communication quality, and therefore the UE 1501 may (implicitly or explicitly) request the deactivation of the NC. In one embodiment of the present invention, the message 1503 is a radio resource control (RRC) message MeasurementReport described in TS 38.331 (version 16.0.0). In addition, in the case of multiple connections, the UE 1501 may report the degradation of the radio link quality with the secondary base station through, for example, the RRC message SCGFailureInformation described in TS 38.331. Then, it is necessary to stop utilizing the current NC configuration of the multiple connections (and a new NC configuration that is more suitable for the new situation may be enabled). Alternatively, the UE 1501 may report that it cannot continue to process the NC due to low battery, high processing load or high temperature. This situation may be reported via an RRC message called UEAssistanceInformation described in TS 38.331.

[0226] After deciding to deactivate NC, base station 1502 may perform step 1506 to deactivate transmission modes (carrier aggregation, dual / multi connectivity) that will no longer be needed when NC is not used. This step includes reconfiguring Figure 5 , Figure 6 or Figure 7 The layers described in .

[0227] In case that configuration of the data radio bearer is required, for example if the CA or DC transmission mode is deactivated, the base station 1502 sends an RRC message RRCReconfiguration as defined in TS 38.331 to the UE 1501. In response to the message (the RRCReconfiguration message), the UE 1501 sends an RRC message RRCReconfigurationComplete as defined in TS 38.331 to the base station 1502.

[0228] Then, a command to deactivate NC is sent to UE 1501. This is achieved here by inserting a notification in the packet header. Preferably, the notification is added in the packet header handled by the layer that performs encoding and decoding. In one embodiment of the present invention, as defined by 3GPP in TS 38.323, the layer that performs NC encoding and NC decoding is the PDCP layer. The base station 1502 deactivates the NC function at step 1512 by disabling its NC encoding engine for data streams. The notification of NC deactivation will be present in at least one packet to be NC encoded and further sent.

[0229] When receiving downlink data packets 1509, UE 1501 will parse the header of each received packet to determine whether NC is deactivated. In the event of such determination, UE 1501 deactivates its NC decoding engine 1725 at step 1511.

[0230] Fig.16 A block diagram 1600 of an apparatus 1605 supporting network coding according to the present invention is shown. The apparatus 1605 may be Figure 1 The relevant UE 101 or base station 102 or Figure 2 The apparatus 1605 includes a receiver 1610, a communication manager 1620, and a transmitter 1630. Each of these elements can communicate with each other via one or more electronic buses.

[0231] The receiver 1610 receives both user and control breads, but may also receive synchronization signals. The receiver 1610 may also receive specific signals for connection establishment purposes. The receiver 1610 may receive signals for measurement or paging purposes.

[0232] The receiver 1610 may refer to Fig.18 1835 or as described in Fig.19 All or part of the description of 1935.

[0233] In one embodiment of the present invention, the receiver 1605 can receive the Figure 3 and Figure 4 Packets encoded with the relevant network coding scheme.

[0234] The communication manager 1620 is responsible for the establishment, control and release of communications. The functionality of the communication manager 1620 may be distributed and not necessarily reside in the same physical location.

[0235] In one embodiment of the present invention, the communication manager 1620 manages Figures 8 to 15 Related network coding configurations and enabling embodiments, in whole or in part.

[0236] The transmitter 1630 transmits both the user bread and the control bread, as well as synchronization signals, measurement signals, paging signals, and signals specific to initiating a connection.

[0237] The transmitter 1630 may refer to Fig.18 1835 or as described in Fig.19 All or part of that described in 1935.

[0238] In one embodiment of the present invention, the transmitter 1630 may send Figure 3 and Figure 4 Packets encoded with the relevant network coding scheme.

[0239] The elements of device 1605 can be implemented using hardware, software and firmware. The hardware here includes CPU, FPGA, ASIC and DSP, GPU and discrete component electronic device (logic or simulation) or any combination of these parts. When the element is virtualized, that is, when the function is implemented by executing the programming code, such code can be executed in a single or parallel thread on the CPU, DSP or GPU or even on a remote general-purpose server. Communication between elements can be carried out through wires, buses or even optical fibers, or if the element is virtualized, it can be carried out through a memory buffer. Elements can be located together or distributed in various places, even remote.

[0240] Fig.17 A first block diagram 1700 of a communication manager 1720 supporting network coding according to an embodiment of the present invention is shown. This is a non-limiting example of a communication manager 1620. The communication manager operates several protocols common to both ends of wireless communication.

[0241] The communication manager 1720 includes an RRC manager 1721, a multi-connection manager 1722, a bearer manager 1723, a network coding engine 1724, a network decoding engine 1725, a PDCP duplication manager 1726, a PDCP entity manager 1727, a carrier aggregation manager 1728, a network coding manager 1729, a parameter manager 1730, an RLC manager 1731, and a MAC manager 1732. Each of these elements can communicate with each other. The network decoding engine 1725 implements Figure 4 The network coding engine 1724 implements the functions described in Figure 3 The network coding manager 1729 is responsible for the setup and release of the network decoding engine 1725 and the network coding engine 1724.

[0242] The carrier aggregation manager 1728 establishes or releases the use of more than one bandwidth portion between the base station and the UE. The carrier aggregation manager has actions on the RLC layer and enables both the primary RLC and the secondary RLC if carrier aggregation is enabled. In operation without network coding or without PDCP duplication, the carrier aggregation manager behaves like a switch and enables the first RLC layer and the second RLC layer alternately.

[0243] The multi-connection manager 1722 establishes or releases the use of more than one bandwidth portion between two base stations and the UE. The multi-connection manager 1722 has actions on the RLC layer. For user data, if multi-connection is enabled, both the primary RLC and the secondary RLC are enabled, or if multi-connection is not enabled, only the primary RLC is enabled.

[0244] The RRC manager 1721 handles the RRC protocol engine. The RRC protocol engine decodes the received message according to the ASN1 specification. In the UE, the RRC manager 1721 extracts the network-coded parameters received from the base station and passes the parameters to the parameter manager 1730, while in the base station, the RRC manager 1721 uses the parameters stored in the parameter manager and pilots the RRC protocol engine so that the latter encodes the parameters according to the ASN.1 specification before sending the parameters.

[0245] The PDCP duplication manager 1726 handles and releases the use of more than one RLC for a data flow. When duplication is enabled, the PDCP duplication manager 1726 behaves like a repeater when sending the same packet to multiple RLC layers.

[0246] The PDCP entity manager 1727 in the context of the present invention handles the PDCP layer. A packet may or may not require header compression, or encryption or integrity. The PDCP entity manager 1727 enables / disables these features. If network coding is enabled, a specific header corresponding to the network coding is selected.

[0247] The bearer manager 1723 handles the mapping of data flows to data radio bearers (DRBs). In 5G NR, DRBs correspond to the use of resources to implement the protocol (PDCP, RLC, MAC) and PHY layers. A DRB can carry several data flows if they belong to the same class of quality of service (QoS). The bearer manager 1723 can enable network coding operations if the packet belongs to the user data plane and disable network coding operations if the packet belongs to the control plane.

[0248] The network coding manager 1729 handles the network coding engine 1724 and the network decoding engine 1725. Sets network coding parameters when necessary. The parameters can be stored in the device or in the core network. The network coding manager 1729 enables / disables the network coding engine 1724 and / or the network decoding engine 1725 according to the selected transmission scheme.

[0249] The RLC manager 1731 handles (one or more than one) RLC layer. If the device is in carrier aggregation or multi-connectivity, more than one RLC layer may be enabled.

[0250] The MAC manager 1732 handles the MAC layer(s). If the device is in multi-connectivity and the device is a UE, more than one MAC layer may be enabled.

[0251] Fig.18 A block diagram 1800 of a UE system 1805 supporting network coding according to one embodiment of the present invention is shown. The device includes components for sending and receiving communications, including a UE communication manager 1820, an I / O controller 1855, a transceiver 1835, one or more antennas 1845, a memory 1825, and a processor 1815. All of these elements may be in communication with each other.

[0252] The memory 1825 includes RAM, ROM, or a combination of both, or as a non-limiting example, a mass storage device such as a disk or solid state drive, etc. Basic Input Output System (BIOS) instructions may be stored in the memory.

[0253] The processor 1845 is configured to execute machine-readable instructions. The execution of these machine-readable instructions causes the device to perform various functions. These functions may involve transmission (and in particular network coding), or involve interaction with peripheral devices (such as keyboards, screens, mice, etc.). The processor may run an operating system such as, for example, iOS, Windows, Android, etc.

[0254] I / O controller 1855 enables these interactions with external peripheral devices by providing the required hardware and by managing the input and output signals.

[0255] The transceiver 1835 performs wireless two-way communications with other wireless devices. It provides the necessary modem and frequency shifter required to connect to Wi-Fi, Bluetooth, LTE, 5GNR, etc.

[0256] Communications are through a collection of one or more antennas adapted to the frequency spectrum of the frequency transposed signal emitted from the baseband modem. Each antenna group may be limited to one antenna, but preferably contains several antennas to provide beamforming capabilities.

[0257] The UE communication manager 1820 handles the communication establishment, control and release of the UE to the radio access network. In one embodiment of the present invention, the UE communication manager 1820 refers to the communication manager 1620 or 1720.

[0258] The UE receives from the base station an indication of the time slots available for its transmission. The UE then knows where in time and frequency it expects incoming data or must send its outgoing data, whether the data belongs to the control plane or the data plane. In particular, the UE may receive network coding parameters from the base station to apply to downlink or uplink transmissions. In one embodiment of the invention, this is based on Figures 8 to 15 The processing flow is realized.

[0259] Fig.19 A block diagram 1900 of a base station 1905 supporting network coding in an embodiment of the present invention is shown. The apparatus includes components for sending and receiving communications, including a base station communication manager 1920, a core network communication manager 1955, a transceiver 1935, one or more antennas 1945, a memory 1925, a processor 1915, and an inter-station communication manager 1965. All of these elements may be in communication with each other.

[0260] The base station communication manager 1920 handles the communication with multiple UEs. The base station communication manager 1920 is responsible for the establishment, control and release of these communications. The base station communication manager 1920 includes a scheduler. The scheduler allocates time-frequency slots to different UE communications. Information about the occupancy schedule of these time slots is sent to all active UEs. In one embodiment of the present invention, the base station communication manager 1920 refers to the communication manager 1620 or 1720.

[0261] The core network communication manager 1955 manages the communication between the base station and the core network.

[0262] The transceiver 1935 performs wireless bidirectional communication with other wireless devices. These devices can be UEs, or even other base stations. The transceiver provides the necessary modems and frequency shifters to connect to a large number of UEs simultaneously using different frequency carriers in time division duplex (TDD) or frequency division duplex (FDD). The transceiver can provide MIMO coding. The transceiver is connected to an antenna.

[0263] The antenna set may be limited to one antenna, but preferably contains several antennas to provide beamforming capabilities.

[0264] Memory 1925 includes RAM, ROM, or a combination of both, or as non-limiting examples, a mass storage device such as a disk or solid-state drive, etc. BIOS instructions may be stored in the memory to support the operating system.

[0265] Processor 1915 executes computer-readable instructions that perform various functions, such as those related to network coding.

[0266] The inter-station communication manager 1965 manages communications with other base stations. The inter-station communication manager may provide a standardized Xn interface as defined by the 3GPP standard to support these communications.

[0267] Fig. 20 2000 is shown illustrating a method for supporting NC configuration determination and setup processing at the base station level in an embodiment of the present invention. Figure 8 , Fig. 9 and Fig.14 The method supports the network coding configuration of the UE and the base station at the base station side. The operations within the method can be performed by the base station 1900, for example, at Fig.19 The communication manager 1920 is implemented in the communication manager 1920.

[0268] refer to Figure 8 , Fig. 9 and Fig.14 , it is assumed that the UE is in connected mode and the UE exchanges control and user data with the base station.

[0269] As a background process, the base station follows the evolution of the network system.

[0270] At step 2001, the base station detects the need to apply network coding on its connection with the UE. According to some embodiments of the present invention, this need may be caused by degradation of transmission quality due to new interference from the UE environment or the connection of a new UE or a new data stream requiring ultra-reliable low-latency communication. These are of course non-limiting examples, and those skilled in the art may consider several other reasons for applying network coding. The need may arise for any bearer (uplink and downlink) that may be established between the base station and the UE.

[0271] At step 2002, the base station determines the feasibility of a network coding scheme. The feasibility depends on the base station capabilities and the UE capabilities that the base station previously requested using the parameter manager 1730 to retrieve the network coding capabilities.

[0272] The base station also checks its own load in the MAC layer managed by the MAC manager 1732 and the queue of the scheduler that manages the air medium resources.

[0273] At step 2003, the base station determines the network coding configuration. To achieve this, the network coding manager 1729 analyzes the capabilities for uplink and / or downlink communications, including but not limited to: the number of branches that may be handled, the processing capabilities of the base station and / or UE, the transmission modes supported by the base station and / or UE...

[0274] In one embodiment of the present invention, the network coding manager 1729 may also select a specific network coding scheme, such as Figure 3 and Figure 4 , but as another example, the network coding manager 1729 may also select a network code based on a Raptor code, depending on the type of service being carried. The base station (or communication manager 1620) sets the network coding engine 1724 and / or the decoding engine 1725 accordingly.

[0275] At step 2004, the base station determines a transmission configuration. Figure 3 and Figure 4 As proposed in the example of , dual connectivity mode or carrier aggregation mode can be used to support network coding schemes, more precisely to define branches to be used to carry coded packets, thereby providing space or time diversity on top of coding diversity. Carrier aggregation and dual connectivity are described in TS38.300 version 16.

[0276] The multiple connection manager 1722 and the carrier aggregation manager 1728 handle these configurations. Note that configuration does not necessarily mean the enabling of network coding processing. And network coding processing can be enabled even if multiple connections or carrier aggregation are not configured.

[0277] At the end of the method, the base station is ready to send a message containing the information needed to set up one or several RLC, one PDCP, one or several MAC layers of the UE and configure its own layers through its manager 1721 , 1731 , 1732 .

[0278] Fig.21 Shown with Figure 8 , Fig.11 , Fig.14 and Fig.15 Flowchart 2100 of a method for supporting NC configuration shared with UE at base station level. The operations within the method may be performed by base station 1900, for example, at Fig.19 The communication manager 1920 is implemented in the communication manager 1920.

[0279] As a background process, the base station checks the queue of messages to be sent on the control plane and the queue of messages received on the control plane.

[0280] At step 2101, the base station sends an NC configuration request message to the UE participating in establishing the network coding process, using the method 2000 to prepare the message. In one embodiment of the present invention, the message is an RRCReconfiguration message as described in TS 38.331, which is enhanced to support network coding as previously discussed herein.

[0281] Then, at step 2102, the base station or the communication manager 1920 receives a network coding configuration completion from the UE. In one embodiment of the present invention, the message is an RRCReconfigurationComplete message as described in TS 38.331.

[0282] It may happen that at the base station, the UE Network Coding Configuration Complete message is not received or not recovered.In one embodiment of the invention, both the UE and the base station should operate according to TS38.331, which indicates the procedures to be applied when information has not been recovered.

[0283] Fig. 22 FIG. 1 shows an example of a method according to an embodiment of the present invention. Figure 8 and Fig.11 2200 of a method for a UE to support NC configuration settings. The operations within the method may be performed by the UE 1800, for example, at Fig.18 The communication manager 1820 is implemented in the communication manager 1820.

[0284] As a background process, the UE checks the queue of messages to be sent on the control plane and the queue of messages received on the control plane.

[0285] At step 2201, the UE receives a network coding configuration request. The message may be, for example, an RRCReconfiguration message described in TS 38.331, which is modified to support network coding as previously discussed herein.

[0286] As an action implied by this message, the UE sets its protocol stack layers (uplink and / or downlink) according to the NC configuration carried by the message.

[0287] Note that configuring does not necessarily mean immediately enabling or disabling network coding processing.

[0288] Then at step 2202, the UE or the communication manager 1820 sends a network coding configuration complete message to the base station. In one embodiment of the present invention, the message is an RRCReconfigurationComplete message described in TS 38.331.

[0289] Fig.23 FIG. 1 shows an example of a method according to an embodiment of the present invention. Fig.14 2300 of a method for enabling network coding supported by a base station. The method can be performed by the base station 1900, for example, Fig.19 The communication manager 1920 is implemented in the communication manager 1920.

[0290] At step 2301, the base station enables the network coding scheme on the base station side according to the established predetermined network coding configuration. In one embodiment of the present invention, the base station has configured its protocol layer, and now the base station enables the NC configuration to be applied by both the base station and the UE. Since the network coding code is applied, changes occur in the packets carried by the bearer. In one embodiment of the present invention, a dedicated NC header (which is part of the PDCP header in another embodiment of the present invention) carries all or part of the network coding configuration. In one embodiment of the present invention, a dedicated NC header (which is part of the RLC header in another embodiment of the present invention) carries all or part of the network coding configuration. In one embodiment of the present invention, a dedicated NC header (which is part of the MAC header in another embodiment of the present invention) carries all or part of the network coding configuration.

[0291] At step 2302 , the base station sends a data packet in which NC configuration information is embedded according to the processing performed at step 2301 .

[0292] Fig.24 FIG. 1 shows an example of a method according to an embodiment of the present invention. Fig.14 Flowchart 2400 of a method for supporting NC configuration determination, setting and enabling processing at UE level. The operation of the method can be performed by UE 1800, for example, at Fig.18 The communication manager 1820 is implemented in the communication manager 1820.

[0293] At step 2401, the UE retrieves Fig.23 The network coding configuration is present in the formatted data packet as described in the method. Fig.23 As described in the description, the transmitted data packets embed payload data and network coding configuration as well as an indication that the data stream packets are network coded.

[0294] At step 2402 , the UE enables network coding using the configuration retrieved at step 2402 .

[0295] Fig.25 FIG. 1 shows an example of a method according to an embodiment of the present invention. Fig.10 Flowchart 2500 of a method for enabling network coding supported by a base station. The operation of the method may be performed by base station 1900, for example, at Fig.19 The communication manager 1920 is implemented in the communication manager 1920.

[0296] At step 2501, the base station enables a network coding scheme at the base station side according to the established predetermined network coding configuration. In one embodiment of the present invention, the base station has previously configured its protocol layer, and now the base station enables the associated NC scheme. As a result of the application of the network coding code, changes occur in the packets carried by the bearer. In one embodiment of the present invention, information indicating that NC coding is applied to the packet is added to one or more NC coding packets. The information may indicate that NC coding will be further applied to subsequent packets.

[0297] In one embodiment of the invention, the information indicates when NC encoding is applied to a data packet. This may include an identifier of the first data packet to be NC encoded (in the case of NC enabled) or not to be NC encoded (in the case of NC disabled). In one embodiment of the invention, the identifier is a sequence number (SN) associated with the data packet.

[0298] In one embodiment of the present invention, the PDCP header of the packet is modified to embed the aforementioned information.

[0299] In one embodiment of the present invention, the RLC header of the packet is modified to embed the aforementioned information.

[0300] In one embodiment of the present invention, the MAC header of the packet is modified to embed the aforementioned information.

[0301] At step 2502 , the base station sends a data packet formatted according to the process of step 2501 to the UE.

[0302] Fig.26 FIG. 1 shows an example of another embodiment according to the present invention. Fig.10 Flowchart 2600 of a method for a UE to support NC configuration settings.

[0303] It is assumed that the UE has previously received the network coding configuration. In one aspect of the invention, the configuration is received from the base station, for example by an RRC message. In another aspect of the invention, the network coding configuration is predetermined and known by both the UE and the base station.

[0304] The operation of the method may be performed by UE 1800, for example, at Fig.18 The communication manager 1820 is implemented in the communication manager 1820.

[0305] At step 2601, the UE retrieves Fig.25 The network coding information is present in the data packet formatted as described in . Fig.25 As described in the description, the transmitted data packet embeds payload data and network coding information indicating that the data packet is NC-coded.

[0306] At step 2602, the UE enables NC decoding using the previously retrieved configuration.

[0307] Fig. 27 FIG. 1 shows an example of a method according to an embodiment of the present invention. Fig.11 , Fig.12 and Fig.15 Flowchart 2700 of a method for a base station to support network coding deactivation. The method can be performed by base station 1900, for example, Fig.19 The communication manager 1920 is implemented in the communication manager 1920.

[0308] As a background process, the base station follows the evolution of the network system.

[0309] At step 2701, the base station detects the need to disable network coding on its connection with the UE. According to some embodiments of the present invention, this need may be caused by a change in the UE environment or by an improvement in transmission quality caused by the disappearance of interference as the UE is disconnected, or the release of a data stream requiring ultra-reliable low-latency communication. These are of course non-limiting examples, and those skilled in the art may consider several other reasons for disabling network coding. The need may arise for any bearer (uplink and downlink) that may be established between the base station and the UE.

[0310] At step 2702, the base station turns off the network coding operation. Then, only the primary carrier is reserved for transmission bearer.

[0311] Fig.28 FIG. 1 shows an example of another embodiment according to the present invention. Fig.13 2800 of a method for a base station to support network coding deactivation. The method can be performed by the base station 1900, for example, Fig.19 The communication manager 1920 is implemented in the communication manager 1920.

[0312] As a background process, the base station follows the evolution of the network system.

[0313] At step 2801, the base station turns off network coding operation.

[0314] In another embodiment of the present invention, the base station embeds network coding deactivation information in one or more network coding data packets, and the network coding deactivation information indicates that NC coding is stopped or will be stopped.

[0315] In one embodiment of the present invention, the PDCP header of the packet is modified to embed the above deactivation information. In another embodiment of the present invention, the RLC header or the MAC header may be modified to embed the above deactivation information.

[0316] At step 2802 , the base station sends the data packet formatted according to the process of step 2801 to the UE.

[0317] Fig.29 FIG. 1 shows an example of a method according to an embodiment of the present invention. Fig.13 Flowchart 2900 of a method for UE to support network coding deactivation. The operation of the method may be performed by UE 1800, for example, at Fig.18 The communication manager 1820 is implemented in the communication manager 1820.

[0318] At step 2901, the UE retrieves Fig.28 The network coding information is present in the data packet formatted as described in . Fig.28 As described in the description, one or more transmitted data packets embed payload data and network coding information indicating that the data stream packet is no longer NC-encoded.

[0319] At step 2902 , the UE deactivates NC decoding using the configuration previously retrieved in step 2901 .

[0320] Fig.30 FIG. 1 shows an example of a method according to an embodiment of the present invention. Fig. 9 Flowchart 3000 of a method for supporting NC configuration determination, setup and activation processing at the base station level. The operation of the method can be performed by the base station 1900, for example, at Fig.19 The communication manager 1920 is implemented in the communication manager 1920.

[0321] Fig. 9 A feature that is somewhat specific to 5G systems, which implements means to reduce UE power consumption, and in particular implements means to reduce the likelihood of soliciting the UE to set a UE in inactive mode for a short period of time every 80 milliseconds instead of every millisecond assuming that the UE is in RRC inactive mode.

[0322] At step 3001, the base station receives an RRC resumption request from a UE, where the RRC resumption request notifies the UE that it needs to re-enter a connection mode with the base station.

[0323] At step 3002, the base station undergoes the process as shown in flowchart 2000 ( Fig. 20 ) in steps 2001 to 2004 described in the text.

[0324] At step 3003, the base station sends a message to the UE resulting from the operation of step 3002. The message contains information related to network coding configuration. In one embodiment of the present invention, as previously discussed herein, the message is an RRCReconfiguration message as described in TS38.331, which is modified to support network coding configuration information.

[0325] Fig.31 FIG. 1 shows an example of another embodiment according to the present invention. Fig. 9 3100 of a method for a UE to support NC configuration settings. The method can be performed by the UE 1800, for example, Fig.18 The communication manager 1820 is implemented in the communication manager 1820. It is assumed that the UE is in RRC inactive mode.

[0326] Because some applications on the UE need to access the network, or perhaps because the UE is paged, the UE needs to exit from the inactive mode to the connected mode.

[0327] At step 3101, the UE sends an RRC recovery request message to the base station.

[0328] At step 3102, the UE receives an RRC resume command from the base station. The message may include configuration parameters required to set the network coding scheme. In one embodiment of the present invention, as previously discussed herein, the message is an RRCResume message as described in TS 38.331, which is modified to support network coding. In other words, the UE ignores its previous configuration (regardless of whether network coding is enabled) and applies the received configuration.

[0329] At step 3103 , the UE configures its protocol stack and enables its network coding according to the network coding configuration received in step 3102 .

[0330] Fig.32 FIG. 1 shows an example of another embodiment according to the present invention. Fig.12 Flowchart 3200 of a method for a base station to support network coding deactivation. The method can be performed by base station 1900, for example, Fig.19 The communication manager 1920 is implemented in the communication manager 1920. It is assumed that the UE is in RRC inactive mode.

[0331] At step 3201, the base station receives an RRC resume request from the UE indicating that it finally needs to re-enter the connected mode with the base station.

[0332] At step 3202 , the base station performs the operations described in flowchart 2700 .

[0333] As a result, even if the base station was enabled before the UE entered the RRC inactive mode, the base station deactivates the network coding operation.

[0334] At step 3003, the base station sends a message generated by the operation of step 3002 to the UE. The message contains the configuration of network coding. The message can be, for example, an RRCResume message as described in TS 38.331, which is enhanced to support network coding. The message carries deactivation information here.

[0335] Fig.33FIG. 1 shows an example of another embodiment according to the present invention. Fig.12 Flowchart 3300 of a method for UE to support network coding deactivation. The operation of the method may be performed by UE 1600, for example, at Fig.16 The communication manager 1620 is implemented in the communication manager 1620.

[0336] Assume that the UE is in RRC inactive mode.

[0337] Because some applications on the UE need to access the network, or perhaps because the UE is paged, the UE needs to exit from the inactive mode to the connected mode.

[0338] At step 3301, the UE sends an RRC recovery request message to the base station.

[0339] At step 3302, the UE receives an RRC resume command from the base station. The message may include the necessary parameters for setting the network coding mode. The message may be, for example, an RRCResume message as described in TS 38.331, which is enhanced to support network coding. In other words, the UE ignores its previous configuration (regardless of whether network coding is enabled) and applies the received configuration.

[0340] At step 3303, the UE configures its protocol stack to follow the network coding configuration, and according to the parameters of the message, network coding may be deactivated.

[0341] Fig.34 An example of a packet format 3400 at the interface between the PDCP layer and the RLC layer according to an embodiment of the present invention is shown. The packet format reuses the PDCP format defined in the specification TS 38.323 issued by the 3GPP organization.

[0342] The first part 3401 is the PDCP header, which includes:

[0343] - a bit indicating whether the information embedded in the data portion 3403 is user data or control data,

[0344] -PDCP Sequence Number (SN),

[0345] - some reserved (R) bits,

[0346] -NC Enable bit, an additional bit (compared to the standardized header) that indicates whether the packet is network coded.

[0347] The second portion 3402 is when the packet contains user data and when the NC enable bit is set to, for example, "1". Fig.14The NC header is added in the context of . The NC header includes an indication of the NC scheme used and a list of NC coefficients used to encode the packet. The number of coefficients (i.e. the number of combined parts in the packet) may be indicated by the NC scheme. Alternatively, instead of a list of coefficients, a code identifying a set of predefined coefficients known to the receiver may be sent.

[0348] The third part 3403 contains data.

[0349] The fourth part 3404 is the packet trailer, which embeds hash information required to verify data integrity.

[0350] The following is the Figure 8 Message 809 and Fig. 9 905 is an illustration of the relevant NC configuration information. NC activation and configuration information (in bold below) can be added in an information element called PDCP-Config, and itself is carried in the parent information element RadioBearerConfig. The RadioBearerConfig information element is carried in the RRC messages RRCReconfiguration and RRCResume. As defined in TS 38.331 (version 16.0.0).

[0351]

[0352]

[0353]

[0354] In this example, the NC enablement and configuration information parameters include:

[0355] -nc-Activation: Boolean value indicating whether NC should be enabled;

[0356] -nc-Config collects the following NC parameters:

[0357] on-Mode: a value among multiple possible values ​​indicating the transmission mode (carrier aggregation or multi-connectivity);

[0358] onc-NumChannel: an integer indicating the number of RLC channels used for NC;

[0359] onc-Scheme: A value among multiple possible values ​​indicating the NC scheme to be applied. This format assumes that both the base station and the UE share the same understanding of which NC scheme corresponds to each possible value. In particular, the NC scheme may identify the number of PDUs to be grouped together in each linear combination;

[0360] onc-CoeffList: list of coefficient values ​​nc-CoeffValue (e.g. 8 bits each in Galois Field 256). The maximum number of coefficients is a constant (e.g. 32). As an example, assuming that no more than 4 different PDUs can be combined together in various NC schemes, the first linear combination uses coefficients belonging to the first set (coefficients from 1 up to 4), the second linear combination uses coefficients belonging to the second set (coefficients from 5 up to 8), and so on;

[0361] nc-CoeffMapping: A list of RLC channels sorted in increasing order of logical channel identity. The number of elements of this list is indicated by the parameter nc-NUMChannel. The value is a bit string where each bit (boolean value) is associated with a linear combination (i.e., with a set of coefficients). If the value is true, the linear combination is sent on this channel.

[0362] This is a non-limiting example, and other formats and combinations of parameters are possible.

[0363] Any step of the algorithm of the present invention may be implemented in software by executing an instruction set or program by a programmable computing machine (such as a PC ("personal computer"), a DSP ("digital signal processor") or a microcontroller); or in hardware by a machine or dedicated component (such as an FPGA ("field programmable gate array") or an ASIC ("application-specific integrated circuit")).

[0364] Although the present invention has been described above with reference to specific embodiments, the present invention is not limited to these specific embodiments, and modifications within the scope of the present invention will be apparent to those skilled in the art.

[0365] Many further modifications and variations will occur to those skilled in the art when referring to the foregoing illustrative embodiments, which are given by way of example only and are not intended to limit the scope of the invention, which is determined solely by the appended claims. In particular, different features from different embodiments may be interchanged where appropriate.

[0366] The various embodiments of the present invention described above may be implemented individually or as a combination of multiple embodiments. In addition, features from different embodiments may be combined where necessary or where a combination of elements or features from various embodiments is beneficial in a single embodiment.

[0367] In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that different features are recited in mutually different dependent claims does not indicate that a combination of these features cannot be used to advantage.

Claims

1. A method for wireless communication between a base station and a user equipment, wherein: The method comprises: sending, by the base station, a data radio bearer configuration; and sending packets between the base station and the user equipment according to the data radio bearer configuration; in: The data radio bearer configuration comprises a network coding configuration; and The transmitted packets are transmitted according to the network coding configuration; and The method further comprises sending, by the base station, a message comprising information for notifying the user equipment of activation of the network coding configuration.

2. The method according to claim 1, wherein: The network coding configuration is embedded in one or more network coding packets.

3. The method according to claim 1, wherein: The method further comprises: receiving, by the base station, a configuration confirmation message to confirm the configuration using the user equipment; and Upon receiving the configuration confirmation message, packet transmission is initiated according to the network coding configuration.

4. The method according to any one of claims 1 to 3, wherein: The network coding configuration includes an indication related to a network coding activation state.

5. The method according to claim 4, wherein: The network coding enabling state is an enabling command or a disabling command.

6. The method according to any one of claims 1 to 3, wherein: The network coding configuration comprises an indication regarding a transmission mode to be applied for sending packets according to the network coding.

7. The method according to claim 6, wherein: The transmission mode is a multi-radio connection.

8. The method according to claim 6, wherein: The transmission mode is carrier aggregation.

9. The method according to any one of claims 1 to 3, wherein: The network coding configuration comprises information about the number of logical channels to be used for sending packets according to the network coding.

10. The method according to any one of claims 1 to 3, wherein: The network coding configuration includes information about a network coding scheme to be used for sending packets according to the network coding.

11. The method according to any one of claims 1 to 3, wherein: The network coding configuration includes information about network coding coefficient values ​​to be used for sending packets according to the network coding.

12. The method according to claim 11, wherein: The information about the network coding coefficient values ​​includes information about the number of network coding coefficient values ​​to be used for transmitting packets according to the network coding.

13. The method according to any one of claims 1 to 3, wherein: In case the network coding configuration does not include any information related to the network coding coefficient values, network coding is performed using predefined network coding coefficient values.

14. The method according to claim 11, wherein: The information related to the network coding coefficient values ​​includes information related to mapping of network coding coefficient values ​​to logical channels.

15. The method according to claim 11, wherein: In case the network coding configuration does not comprise any information about mapping of network coding coefficient values ​​to logical channels, a predefined mapping of network coding coefficient values ​​to logical channels is applied.

16. The method according to claim 1, wherein: The method further comprises: Select the logical channel to be used for network coding.

17. The method according to claim 1, wherein: The method further comprises: A selection is made between carrier aggregation and multi-radio connection as a transmission mode for transmitting packets according to the network coding configuration.

18. The method according to claim 1, wherein: The method further comprises: A plurality of network coding schemes are selected to be used for sending packets according to the network coding configuration.

19. The method according to claim 1, wherein: The method further comprises: A plurality of radio link control entities associated with the logical channels are set.

20. A system for wireless communication between a base station and a user equipment, wherein: The base station and the user equipment include a processor, wherein the processor is configured to: sending, by the base station, a data radio bearer configuration; and sending packets between the base station and the user equipment according to the data radio bearer configuration; in: The data radio bearer configuration comprises a network coding configuration; and The transmitted packets are transmitted according to the network coding configuration; and The processor is further configured to send, by the base station, a message including information for notifying the user equipment of activation of the network coding configuration.

21. A computer program product for a programmable device, the computer program product comprising a sequence of instructions for implementing the method according to claim 1 when loaded into and executed by the programmable device.

22. A non-transitory computer-readable storage medium storing instructions of a computer program for implementing the method according to claim 1.

23. A base station device, used for wireless communication between the base station and user equipment, wherein: The base station device comprises a processor, wherein the processor is configured to: sending a data radio bearer configuration to the user equipment; exchanging packets with the user equipment according to the data radio bearer configuration; and sending a message including information for notifying the user equipment of activation of a network coding configuration; in: The data radio bearer configuration includes the network coding configuration; and The exchanged packets are sent according to the network coding configuration.

24. A user equipment device, used for wireless communication between a base station and a user equipment, wherein: The user equipment device comprises a processor, the processor being configured to: receiving a data radio bearer configuration from the base station; exchanging packets with the base station according to the data radio bearer configuration; as well as receiving, from the base station, a message including information for notifying the user equipment of activation of a network coding configuration; in: The data radio bearer configuration includes the network coding configuration; and The exchanged packets are sent according to the network coding configuration.

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