Method and apparatus for generating modulation symbols

Abstract

The present disclosure proposes a method and apparatus for generating modulation symbols. Specifically, the method of the present disclosure, performed by a user equipment, comprises the steps of: generating coded bits by applying channel coding to a transport block; and generating modulation symbols by performing superposition modulation on the coded bits on the basis of layer groups.

Description

Method for generating modulation symbols and apparatus thereof

[0001] The present disclosure relates to a method for generating modulation symbols and an apparatus thereof.

[0002] The 5G mobile communication system is a successor technology to LTE (Long Term Evolution) and is a new clean-slate type of mobile communication system characterized by high performance, low latency, and high availability. In the case of 5G NR, all available spectrum resources can be utilized, ranging from low-frequency bands below 1 GHz to intermediate frequency bands between 1 GHz and 10 GHz, and high-frequency (millimeter wave) bands above 24 GHz. Based on the underlying technology of 5G mobile communication, 6G mobile communication systems are being developed.

[0003] The 6G mobile communication system aims for (i) very high data rates per device, (ii) a very large number of connected devices, (iii) global connectivity, (iv) very low latency, (v) reduced energy consumption of battery-free IoT (internet of things) devices, (vi) ultra-reliable connectivity, and (vii) connected intelligence with machine learning capabilities. The vision of the 6G system can be four aspects: intelligent connectivity, deep connectivity, holographic connectivity, and ubiquitous connectivity.

[0004] The present disclosure proposes a method and apparatus for mapping to layer groups based on the priority of code bits during Superposition Modulation (SM).

[0005] In addition, the present disclosure proposes a method and apparatus for setting the size of a layer group based on the number of code bits mapped to the layer group.

[0006] In addition, the present disclosure proposes a method and apparatus for mapping code bits to layer groups and setting the size of layer groups based on a block memory structure.

[0007] In addition, the present disclosure proposes a method and apparatus for having different power between layers within the same layer group.

[0008] The technical problems to be solved in this disclosure are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which this disclosure belongs from the description below.

[0009] The present disclosure proposes a method for generating modulation symbols and an apparatus thereof.

[0010] A method performed by a terminal of the present disclosure comprises the steps of generating a code bit by applying channel coding to a transmission block and generating a modulation symbol by performing nested modulation based on layer groups on the code bit, wherein the layer groups have different power levels, the code bit is mapped to one of the layer groups based on priority, and the size of the layer groups can be set based on the ratio of the number of code bits mapped to the layer groups.

[0011] In addition, in the method of the present disclosure, the code bits may be mapped to a layer group with a higher power level as their priority increases.

[0012] Additionally, in the method of the present disclosure, the size of at least one of the layer groups based on the ratio of the number of code bits mapped to the layer group is a real number that is not an integer, and the size of the layer groups may be set based on an accumulated error to have an integer value.

[0013] In addition, in the method of the present disclosure, the size of at least one of the layer groups based on the ratio of the number of code bits mapped to the layer group is a real number rather than an integer, and the size of the layer groups may be set based on a block memory having a number of columns associated with a resource element (RE) and a number of rows associated with a modulation order.

[0014] In addition, in the method of the present disclosure, the code bits are written to the block memory one row at a time in order of priority, and the bits of each column can be mapped to one of the layer groups in order.

[0015] In addition, in the method of the present disclosure, the size of the layer groups may be set based on an accumulated error to have an integer value.

[0016] In addition, in the method of the present disclosure, the modulation symbol may be generated by reading the block memory one column at a time in sequence from the block memory.

[0017] In addition, in the method of the present disclosure, each of the layer groups comprises one or more layers, and each of the one or more layers within the same layer group may have different power levels based on the power ratio within the group.

[0018] In addition, in the method of the present disclosure, the power ratio within the group may be a value less than 1.

[0019] Additionally, the terminal of the present disclosure comprises one or more transceivers, one or more processors, and one or more memories connected to the one or more processors and storing instructions, wherein the instructions may enable the terminal to perform all or some steps of a method according to any one of the methods of the present disclosure based on execution by the one or more processors.

[0020] Additionally, an apparatus comprising one or more memories of the present disclosure and one or more processors connected to said one or more memories may store instructions that cause said apparatus to perform all or some steps of a method according to any one of the methods of the present disclosure, based on execution by said one or more processors.

[0021] Additionally, a non-transitory computer-readable storage medium storing instructions of the present disclosure, said instructions executable by one or more processors, may enable a terminal to perform all or some steps of a method according to any one of the methods of the present disclosure.

[0022] Additionally, a method performed by a base station of the present disclosure comprises the steps of generating a code bit by applying channel coding to a transmission block and generating a modulation symbol by performing overlapping modulation based on layer groups on the code bit, wherein the layer groups have different power levels, the code bit is mapped to one of the layer groups based on priority, and the size of the layer groups can be set based on the ratio of the number of code bits mapped to the layer groups.

[0023] Additionally, the base station of the present disclosure comprises one or more transceivers and one or more processors and one or more memories connected to the one or more processors and storing instructions, wherein the instructions may enable the base station to perform all or some steps of the method according to the present disclosure based on execution by the one or more processors.

[0024] According to the present disclosure, by mapping to layer groups based on the priority of code bits during Superposition Modulation (SM), there is an effect of implementing a method and apparatus that improve the decoding performance of a receiver.

[0025] In addition, according to the present disclosure, by setting the size of a layer group based on the number of code bits mapped to a layer group, there is an effect of implementing a method and apparatus for performing differential power allocation according to priority.

[0026] In addition, according to the present disclosure, by mapping code bits to a layer group based on a block memory structure and setting the size of the layer group, there is an effect of implementing a method and apparatus that eliminate ambiguity when the calculated layer group size is a real number rather than an integer and simultaneously improve decoding performance.

[0027] In addition, according to the present disclosure, by having different powers among layers within the same layer group, there is an effect of implementing a method and apparatus that eliminates ambiguity in layer distinction caused by layers within the same group all having the same power.

[0028] In addition, according to the present disclosure, there is an effect of implementing a method and apparatus that improve FEC decoding performance by placing bits with the same priority in the same group and allocating power to the group according to priority.

[0029] In addition, according to the present disclosure, there is an effect of implementing a method and apparatus that can resolve the ambiguity problem of SM symbols by granting degrees of freedom to allocate power even between layers within the same group.

[0030] In addition, according to the present disclosure, in the case of equal power allocation of SM, transmission reliability can be controlled according to the priority of code bits by allocating a different number of layers for each RE.

[0031] The effects obtainable from the present disclosure are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present disclosure belongs from the description below.

[0032] FIG. 1 illustrates an exemplary flexible network topology to which some examples of the present disclosure may be applied.

[0033] FIG. 2 illustrates a communication system to which the present disclosure applies.

[0034] FIG. 3 illustrates an example of a wireless device that can be applied to the present disclosure.

[0035] FIG. 4 illustrates a communication procedure between a first node and a second node applicable to the present disclosure.

[0036] Figure 5 illustrates the structure of a base graph in 5G NR.

[0037] Figure 6 is an example of a 16QAM interleaver.

[0038] Figure 7 illustrates the structure of an SM transmitter.

[0039] FIG. 8 illustrates a block memory structure for assigning FEC code bits to overlapping modulation symbols.

[0040] FIG. 9 illustrates a block memory structure for assigning FEC code bits according to Example 3 to an overlapping modulation symbol.

[0041] Figure 10 illustrates the power per layer according to mathematical formula 13.

[0042] FIG. 11 illustrates a block memory structure for assigning FEC code bits according to Example 4 to SM symbols.

[0043] FIG. 12 illustrates the power per layer according to Example 4.

[0044] FIG. 13 illustrates a transmitter structure according to Example 6.

[0045] FIG. 14 is a flowchart for explaining the operation method of a device according to the present disclosure.

[0046] In the present disclosure, "A or B" may mean "only A," "only B," or "both A and B." Alternatively, in the present disclosure, "A or B" may be interpreted as "A and / or B." For example, in the present disclosure, "A, B or C" may mean "only A," "only B," "only C," or "any combination of A, B and C."

[0047] A slash ( / ) or a comma used in the present disclosure may mean "and / or." For example, "A / B" may mean "A and / or B." Accordingly, "A / B" may mean "only A," "only B," or "both A and B." For example, "A, B, C" may mean "A, B or C."

[0048] In the present disclosure, "at least one of A and B" may mean "only A," "only B," or "both A and B." Additionally, in the present disclosure, the expressions "at least one of A or B" or "at least one of A and / or B" may be interpreted as synonymous with "at least one of A and B."

[0049] Additionally, in the present disclosure, "at least one of A, B and C" may mean "only A," "only B," "only C," or "any combination of A, B and C." Additionally, "at least one of A, B or C" or "at least one of A, B and / or C" may mean "at least one of A, B and C."

[0050] Additionally, parentheses used in the present disclosure may mean "for example." Specifically, when indicated as "control information (PDCCH)," "PDCCH" may be proposed as an example of "control information." In other words, the "control information" of the present disclosure is not limited to "PDCCH," and "PDCCH" may be proposed as an example of "control information." Furthermore, even when indicated as "control information (i.e., PDCCH)," "PDCCH" may be proposed as an example of "control information."

[0051] In the following explanation, 'when, if, in case of' can be replaced with 'based on'.

[0052] Technical features described individually within one drawing in this disclosure may be implemented individually or simultaneously.

[0053] Hereinafter, preferred embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description disclosed below, together with the accompanying drawings, is intended to describe exemplary embodiments of the present disclosure and is not intended to represent the only embodiment in which the present disclosure may be practiced. The detailed description below includes specific details to provide a complete understanding of the present disclosure.

[0054] In the present disclosure, a terminal is a user-side device (user equipment, UE) or a consumer-side device, and may also be referred to as a first node that receives / transmits signals from / to a base station / second node / IAB node / Transmission-Reception Point (TRP). A terminal may correspond to a physical node or a logical node. A terminal may correspond to a user-side endpoint or an intermediate point between other endpoints. In communication between two points not limited to endpoints (including one-to-one / many-to-one / one-to-many / many-to-many communication), a terminal may correspond to a served node. A terminal may be a fixed-location node or a non-fixed-location (or mobile) node.

[0055] In the present disclosure, a base station (BS) is a device on the network side and may be referred to as a second node / IAB node / x-nodeB (x-NodeB, where x may be an abbreviation related to Radio Access Technology (RAT)) / Transmission-Reception Point (TRP). A base station may correspond to a physical node or a logical node. A base station may correspond to an endpoint on the network side or an intermediate point between other endpoints. In communication between two points not limited to endpoints (including one-to-one / many-to-one / one-to-many / many-to-many communication), a base station may correspond to a serving node. A base station may be a node with a fixed location or a node without a fixed location.

[0056] In the present disclosure, higher layer parameters may be set for the terminal, pre-set, or pre-defined. For example, a base station may transmit higher layer parameters to the terminal. For example, the terminal may transmit parameters such as capability to the base station as higher layer parameters. For example, higher layer parameters may be transmitted via radio resource control (RRC) signaling or medium access control (MAC) signaling.

[0057] In the present disclosure, information / state / parameters being "configured or pre-configured" may be interpreted as information / state / parameters being provided or pre-provided to the terminal through pre-defined signaling (e.g., SIB, MAC, RRC) from the base station. In the present disclosure, information / state / parameters being "defined or pre-defined" may be interpreted as being known or stored in advance by the base station and the terminal without signaling between the base station and the terminal.

[0058] The technology described in this disclosure can be used in various wireless communication systems such as CDMA (code division multiple access), FDMA (frequency division multiple access), TDMA (time division multiple access), OFDMA (orthogonal frequency division multiple access), SC-FDMA (single carrier frequency division multiple access), etc. CDMA can be implemented with wireless technologies such as UTRA (universal terrestrial radio access) or CDMA2000. TDMA can be implemented with wireless technologies such as GSM (global system for mobile communications) / GPRS (general packet radio service) / EDGE (enhanced data rates for GSM evolution). OFDMA can be implemented with wireless technologies such as IEEE (institute of electrical and electronics engineers) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, E-UTRA (evolved UTRA), LTE (long term evolution), 5G NR, etc.

[0059] The technology described in this disclosure can be implemented as 6G wireless technology and applied to various 6G systems. For example, 6G systems may have key factors such as eMBB (enhanced mobile broadband), URLLC (ultra-reliable low latency communications), mMTC (massive machine-type communication), AI (artificial intelligence) integrated communication, tactile internet, high throughput, high network capacity, high energy efficiency, low backhaul and access network congestion, and enhanced data security.

[0060] 6G network architecture

[0061] FIG. 1 illustrates an exemplary flexible network topology to which some examples of the present disclosure may be applied.

[0062] To compensate for incomplete areas of network coverage, a network topology in which the Split Radio Access Network (RAN) is configured more flexibly and resiliently may be considered. To this end, various nodes such as IAB nodes, relays, and RF repeaters, as exemplified in Fig. 1, may be applied, and NTN may be integrated. For example, an IAB node may correspond to a node that provides wireless backhaul. For example, a relay may refer to any intermediate point, and in the case of a sidelink relay where a terminal functions as a relay, it may collectively refer to a terminal-to-network (U2N) relay and a terminal-to-terminal (U2U) relay. For example, an RF repeater may correspond to a node that performs simple signal amplification and forwarding functions, and in the case of a network-controlled repeater, it may adjust transmit / receive settings based on information provided by the network as well as signal amplification and forwarding. For example, an NTN node may correspond to a satellite or aircraft that provides NTN coverage that is difficult for a terrestrial network to provide. In addition to these examples, various intermediate points can be introduced to improve network topology.

[0063] Referring to FIG. 1, a split RAN can support the division of a base station into one centralized unit (CU) and one or more distributed units (DU). The CU and DU may correspond to logical units. The CU may be further divided into a control plane (CP) portion and one or more user plane (UP) portions. Since a failure in the CU-CP affects not only the CU-UP but also the DU, various intermediate points may be introduced to compensate for this.

[0064] An intermediate point may correspond to a terminal or a base station depending on its relative relationship with other nodes. For example, an IAB node may include a mobile-termination (MT) portion and a DU. The MT can connect the IAB node to a donor node. The DU of the IAB node may serve other terminals or connect to other IAB nodes to provide multi-hop wireless backhaul to terminals. In other words, an IAB node may correspond to a base station in its relative relationship with user-side nodes and to a terminal in its relative relationship with network-side nodes.

[0065] In some examples of the present disclosure, the description of a terminal may apply equally to an intermediate point corresponding to a terminal in relation to a network-side endpoint as well as to a user-side endpoint. Similarly, in some examples of the present disclosure, the description of a base station may apply equally to an intermediate point corresponding to a base station in relation to a user-side endpoint as well as to a network-side endpoint. However, in most cases where there is no additional description of the operation of three or more entities, the communication entities in the present disclosure are briefly described by the term terminal and / or base station (or first node and / or second node), wherein the term terminal and / or base station (or first node and / or second node) is interpreted to include or replace any endpoint or any intermediate point in relation to other nodes.

[0066] That is, for the sake of brevity of description in some examples of the present disclosure, the subject of the operation may be referred to as a base station and / or terminal (or a first node and / or a second node). Additionally, the term base station and / or terminal (or a first node and / or a second node) may be interpreted or substituted as in the following examples. For instance, the base station (or the first node) and the terminal (or the second node) may correspond to a first endpoint and a second endpoint, respectively; may correspond to an endpoint and an intermediate point, respectively; may correspond to an intermediate point and an endpoint, respectively; or may correspond to a first intermediate point and a second intermediate point, respectively.

[0067] In the present disclosure, there may be no intermediate points between a base station and a terminal, or there may be one or more. If intermediate points exist, the intermediate points may correspond to IAB nodes, relays, RF repeaters, NTN (non-terrestrial network) nodes, or nodes supporting other functions. The intermediate points may be nodes with a fixed location or nodes with an indefinite location.

[0068] (Systems applicable to the present disclosure)

[0069] The communication system (100) of FIG. 2 to which the present disclosure applies includes a wireless device (110), a network device (120), and a network (130). Here, the wireless device (110) refers to a device that performs communication using wireless access technology (e.g., LTE, LTE-A, LTE-A pro, NR, 5G, 5G-A, 6G) and may be referred to as a communication / wireless / 5G / 6G device. Although not limited thereto, the wireless device (110) may include a robot (110a), a vehicle (110b-1, 110b-2), an XR (extended reality) device (110c), a hand-held device (110d), a home appliance (110e), an IoT (Internet of Thing) device (110f), and an AI (artificial intelligence) device / server (110g). For example, the vehicle may include a vehicle equipped with wireless communication capabilities, an autonomous vehicle, a vehicle capable of performing inter-vehicle communication, etc. Here, the vehicle (110b-1, 110b-2) may include an unmanned aerial vehicle (UAV) (e.g., a drone). The XR device (110c) includes an augmented reality (AR) / virtual reality (VR) / mixed reality (MR) device and may be implemented in the form of a head-mounted device (HMD), a head-up display (HUD) equipped in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance, digital signage, a vehicle, a robot, etc. The portable device (110d) may include a smartphone, a smartpad, a wearable device (e.g., a smartwatch, smart glasses), a computer (e.g., a laptop, etc.). The home appliance (110e) may include a TV, a refrigerator, a washing machine, etc. The IoT device (110f) may include a sensor, a smart meter, etc. The wireless device (110) may correspond to a terminal (or first node) or an intermediate point.The network device (120) may correspond to a base station (or a second node) or another intermediate point. For example, the network device (120) may also be implemented as a wireless device (110), and a specific wireless device (120a) may operate as a network device (120) to another wireless device (110).

[0070] Wireless devices (110a to 110f) can be connected to a network (130) through a network device (120). AI technology may be applied to the wireless devices (110a to 110f), and the wireless devices (110a to 110f) can be connected to an AI server (110g) through the network (130). The network (130) can be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR) network, or a 6G network. The wireless devices (110a to 110f) may communicate with each other through the network device (120) / network (130), but may also communicate directly (e.g., sidelink communication) without going through the network device (120) / network (130). For example, vehicles (110b-1, 110b-2) can communicate directly (e.g., V2V (vehicle to vehicle) / V2X (vehicle to everything) communication). Also, an IoT device (110f) (e.g., a sensor) can communicate directly with another IoT device (e.g., a sensor) or other wireless devices (110a to 110f).

[0071] Wireless communication / connection (150a, 150b, 150c) can be established between wireless devices (110a to 110f) / network devices (120) and between network devices (120). Here, wireless communication / connection can be established through various wireless access technologies such as uplink / downlink communication (150a), sidelink communication (150b) (or D2D communication), and communication between network devices (150c) (e.g., relay, IAB (integrated access backhaul)). Through wireless communication / connection (150a, 150b, 150c), wireless devices and network devices / wireless devices, and network devices and network devices can transmit / receive wireless signals to / from each other. For example, wireless communication / connection (150a, 150b, 150c) can transmit / receive signals through various physical channels. To this end, based on the various descriptions of the present disclosure, at least some of the following may be performed: a process for setting various configuration information for transmitting / receiving wireless signals, a process for various signal processing (e.g., channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), a resource allocation process, etc.

[0072] (Applicable devices to the present disclosure)

[0073] FIG. 3 illustrates an example of a wireless device that can be applied to the present disclosure.

[0074] Referring to FIG. 3, the wireless device (200) can transmit and receive wireless signals through various wireless access technologies (e.g., LTE, LTE-A, LTE-A pro, NR, 5G, 5G-A, 6G). The wireless device (200) includes at least one processor (202) and / or at least one memory (204), and / or may further include at least one transceiver (206) and / or at least one antenna (208).

[0075] The processor (202) controls the memory (204) and / or the transceiver (206) and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or sequences of operation disclosed in this document. For example, the processor (202) may process information within the memory (204) to generate a first information / signal and then transmit a wireless signal containing the first information / signal through the transceiver (206). Additionally, the processor (202) may receive a wireless signal containing a second information / signal through the transceiver (206) and then store information obtained from the signal processing of the second information / signal in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, memory (204) may store software code containing instructions for performing some or all of the processes controlled by the processor (202) or for performing the descriptions, functions, procedures, proposals, methods, and / or sequences of operations disclosed in this document. Here, the processor (202) and memory (204) may be part of a communication modem / circuit / chip designed to implement wireless communication technology. A transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals through at least one antenna (208). The transceiver (206) may include a transmitter and / or receiver. The transceiver (206) may be interchangeable with a radio frequency (RF) unit. In this disclosure, a wireless device may mean a communication modem / circuit / chip.

[0076] Hereinafter, hardware elements of the wireless device (200) will be described in more detail. Although not limited thereto, at least one protocol layer may be implemented by at least one processor (202). For example, at least one processor (202) may implement at least one layer (e.g., functional layers such as PHY (physical), MAC (media access control), RLC (radio link control), PDCP (packet data convergence protocol), RRC (radio resource control), and SDAP (service data adaptation protocol). At least one processor (202) may generate at least one PDU (Protocol Data Unit) and / or at least one SDU (service data unit) according to the descriptions, functions, procedures, proposals, methods and / or operation sequences disclosed in this document. At least one processor (202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods and / or operation sequences disclosed in this document. At least one processor (202) may generate a signal (e.g., baseband signal) including a PDU, SDU, message, control information, data, or information according to the functions, procedures, proposals, and / or methods disclosed in this document and provide it to at least one transceiver (206). At least one processor (202) may receive a signal (e.g., baseband signal) from at least one transceiver (206) and may obtain a PDU, SDU, message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this document.

[0077] At least one processor (202) may be referred to as a controller, microcontroller, microprocessor, or microcomputer. At least one processor (202) may be implemented by hardware, firmware, software, or a combination thereof. For example, at least one application-specific integrated circuit (ASIC), at least one digital signal processor (DSP), at least one digital signal processing device (DSPD), at least one programmable logic device (PLD), or at least one field programmable gate array (FPGA) may be included in at least one processor (202). The descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this document may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. Firmware or software configured to perform the descriptions, functions, procedures, proposals, methods, and / or operation sequences disclosed in this document may be included in at least one processor (202) or stored in at least one memory (204) and driven by at least one processor (202). The descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed in this document may be implemented using firmware or software in the form of code, instructions, and / or sets of instructions.

[0078] At least one memory (204) may be connected to at least one processor (202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. At least one memory (204) may be composed of ROM (read-only memory), RAM (random access memory), EPROM (erasable programmable read-only memory), flash memory, hard drive, registers, cache memory, computer read storage media, and / or combinations thereof. At least one memory (204) may be located inside and / or outside of at least one processor (202). Additionally, at least one memory (204) may be connected to at least one processor (202) via various technologies, such as wired or wireless connections.

[0079] At least one transceiver (206) may transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or operation flowcharts, etc. of this document to at least one other device. At least one transceiver (206) may receive user data, control information, wireless signals / channels, etc., as mentioned in the descriptions, functions, procedures, proposals, methods and / or operation flowcharts, etc. disclosed in this document from at least one other device. For example, at least one transceiver (206) may be connected to at least one processor (202) and may transmit and receive wireless signals. For example, at least one processor (202) may control at least one transceiver (206) to transmit user data, control information, or wireless signals to at least one other device. Additionally, at least one processor (202) may control at least one transceiver (206) to receive user data, control information, or wireless signals from at least one other device. Additionally, at least one transceiver (206) may be connected to at least one antenna (208), and at least one transceiver (206) may be configured to transmit and receive user data, control information, wireless signals / channels, etc., as described in the descriptions, functions, procedures, proposals, methods, and / or operation sequence diagrams disclosed in this document through at least one antenna (208). In this document, at least one antenna may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports). At least one transceiver (206) may convert the received wireless signals / channels, etc., from RF band signals to baseband signals in order to process the received user data, control information, wireless signals / channels, etc., using at least one processor (202). At least one transceiver (206) may convert the processed user data, control information, wireless signals / channels, etc., from baseband signals to RF band signals using at least one processor (202).To this end, at least one transceiver (206) may include an (analog) oscillator and / or filter.

[0080] The components of the wireless device described with reference to FIG. 3 may be referred to by other terms in terms of their function. For example, the processor (202) may be referred to as the control unit, the transceiver (206) as the communication unit, and the memory (204) as the storage unit. In some cases, the communication unit may be used to mean at least a part of the processor (202) and the transceiver (206).

[0081] The structure of the wireless device described with reference to FIG. 3 can be understood as the structure of at least part of various devices. For example, the structure of the wireless device exemplified in FIG. 3 may be at least part of the various devices described with reference to FIG. 2 (e.g., robot (110a), vehicle (110b-1, 110b-2), XR device (110c), portable device (110d), home appliance (110e), IoT device (110f), AI device / server (110g)). Furthermore, according to various embodiments, the device may include other components in addition to the components exemplified in FIG. 3.

[0082] For example, the device may be a portable device such as a smartphone, smartpad, wearable device (e.g., smart watch, smart glasses), or portable computer (e.g., laptop, etc.). In this case, the device may further include at least one of a power supply unit that supplies power and includes a wired / wireless charging circuit, a battery, etc., an interface unit that includes at least one port for connection with another device (e.g., audio input / output port, video input / output port), and an input / output unit for inputting and outputting video information / signals, audio information / signals, data, and / or information input by a user.

[0083] For example, the device may be a mobile device such as a mobile robot, vehicle, train, manned / unmanned aerial vehicle (AV), or ship. In this case, the device may further include at least one of a drive unit comprising at least one of an engine, motor, power train, wheel, brake, and steering device of the device; a power supply unit that supplies power and includes a wired / wireless charging circuit, battery, etc.; a sensor unit that senses state information, environmental information, and user information of the device or its surroundings; an autonomous driving unit that performs functions such as path maintenance, speed control, and destination setting; and a position measurement unit that acquires position information of the moving body through a GPS (global positioning system) and various sensors.

[0084] For example, the device may be an XR device such as an HMD, a HUD (head-up display) equipped in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance, digital signage, a vehicle, a robot, etc. In this case, the device may further include at least one of a power supply unit that supplies power and includes a wired / wireless charging circuit, a battery, etc., an input / output unit that acquires control information, data, etc. from the outside and outputs a generated XR object, and a sensor unit that senses state information, environment information, and user information of the device or the surroundings of the device.

[0085] For example, the device may be a robot that can be classified into industrial, medical, household, military, etc., depending on the purpose or field of use. In this case, the device may further include at least one of a sensor unit that senses state information, environmental information, and user information of the device or its surroundings, and a drive unit that performs various physical actions, such as moving robot joints.

[0086] For example, the device may be an AI device such as a TV, projector, smartphone, PC, laptop, digital broadcasting terminal, tablet PC, wearable device, set-top box (STB), radio, washing machine, refrigerator, digital signage, robot, vehicle, etc. In this case, the device may further include at least one of an input unit that acquires various types of data from the outside, an output unit that generates output related to sight, hearing, or touch, a sensor unit that senses state information, environmental information, and user information of the device or its surroundings, and a training unit that learns a model composed of an artificial neural network using training data.

[0087] The structure of the wireless device exemplified in FIG. 3 may be understood as part of a terminal (or first node), or part of an intermediate point, or part of a base station (or second node). If the device exemplified in FIG. 3 is a base station (or second node), the device may further include a wired transceiver for front haul and / or back haul communication. However, if the front haul and / or back haul communication is based on wireless communication, at least one transceiver (206) exemplified in FIG. 3 is used for front haul and / or back haul communication, and the wired transceiver may not be included.

[0088] Communication procedures

[0089] FIG. 4 illustrates a communication procedure between a first node (e.g., a terminal) and a second node (e.g., a base station) applicable to the present disclosure. The second node of FIG. 4 supports dynamic spectrum sharing (DSS) and can provide connectivity to both nodes where 6G technology is implemented and nodes where pre-6G wireless communication technology (e.g., 5G, 4G) is implemented. That is, the first node of FIG. 4 may have 6G technology implemented or pre-6G wireless communication technology (e.g., 5G, 4G) implemented. Additionally, the first node and / or the second node may support full duplex mode as well as non-overlapping full duplex mode.

[0090] In FIG. 4, for the sake of simplicity of explanation, the first node and the second node are assumed to be a terminal and a base station, respectively, and the operation of the terminal (110) and the base station (120) transmitting and / or receiving data, and the operation performed prior to this, are illustrated. However, the operation of FIG. 4 is not limited to the operation between the terminal and the base station, but can be interpreted as the operation between the first node and the second node. Additionally, FIG. 4 illustrates the operation of direct transmission and reception of wireless signals between the terminal (110) and the base station (120), but there may be one or more intermediate points between the terminal (110) and the base station (120), and wireless signals may be transmitted and received via one or more intermediate points.

[0091] Referring to FIG. 4, in step 101, the terminal (110) and the base station (120) perform synchronization. For example, the terminal (110) performs an initial cell search operation. Specifically, the terminal (110) can detect a synchronization signal for at least one base station connection transmitted from the base station (120) according to a predefined rule. Here, the synchronization signal may include a plurality of synchronization signals classified according to structure or use (e.g., a first synchronization signal (e.g., a primary synchronization signal), a second synchronization signal (e.g., a secondary synchronization signal), etc.). Through this, the terminal (110) can identify the boundary of the unit (e.g., frame, subframe, slot and / or symbol) constituting the wireless signal transmission of the base station (120) and obtain information about the base station (120) (e.g., a cell identifier).

[0092] In step 103, the terminal (110) obtains system information transmitted from the base station (120). The system information is information related to the attributes, characteristics, and / or capabilities of the base station (120) required to connect to the base station (120) and use the service, and can be classified according to content (e.g., whether it is essential for connection), transmission structure (e.g., channel used, whether it is provided on-demand), etc., and can be classified, for example, into first system information (e.g., MIB (master information block), primary system information), second system information (e.g., SIB (system information block), secondary system information), etc. If necessary, the terminal (110) may transmit a signal requesting system information prior to receiving the system information. However, the request and provision of system information may be performed after the random access procedure described later.

[0093] In step 105, the terminal (110) and the base station (120) perform a random access procedure. The terminal (110) may transmit and / or receive at least one message for a random access procedure (e.g., a random access preamble, a RAR (random access response) message, etc.) based on information related to the channel for the random access procedure of the base station (120) obtained through system information (e.g., channel location, channel structure, structure of a supported preamble, etc.). For example, the terminal (110) may transmit a first message (e.g., a preamble, MSG1) through the channel for the random access procedure, receive a second message (e.g., a RAR message, MSG2), transmit a third message (e.g., MSG3) containing information related to the terminal (110) (e.g., identification information) using scheduling information included in the second message, and receive a fourth message (e.g., MSG4) for contention resolution and / or connection establishment. As another example, the first message and the third message can be transmitted and received as a single message, or the second message and the fourth message can be transmitted and received as a single message.

[0094] In step 107, the terminal (110) and the base station (120) perform signaling of control information. Here, the control information may be defined in various layers, such as a layer that controls the connection (e.g., a radio resource control (RRC) layer), a layer that handles mapping between logical channels and transmission channels (e.g., a media access control (MAC) layer), and a layer that handles physical channels (e.g., a physical (PHY) layer). For example, the terminal (110) and the base station (120) may perform at least one of signaling to establish a connection, signaling to determine settings related to communication, and signaling to indicate allocated resources.

[0095] In step 109, the terminal (110) and the base station (120) transmit and / or receive data. That is, the terminal (110) and the base station (120) can process, transmit and / or receive data based on the signaling of control information. For example, when transmitting data, the terminal (110) or the base station (120) may perform at least one of channel encoding, rate matching, scrambling, constellation mapping, layer mapping, waveform modulation, antenna mapping, and resource mapping on the information bits. Conversely, when receiving data, the terminal (110) or the base station (120) may perform at least one of signal extraction from resources, antenna-specific waveform demodulation, signal placement considering layer mapping, constellation demapping, descrambling, and channel decoding.

[0096] Glossary of Terms

[0097] The symbols / abbreviations / terms used in this disclosure are as follows.

[0098] QAM: Quadrature Amplitude Modulation

[0099] LDPC: Low Density Parity Check

[0100] FEC: Forward Error Correction

[0101] SM: Superposition Modulation

[0102] NR: New Radio

[0103] BPSK: Binary Phase Shift Keying

[0104] SM-EPA: Superposition Modulation with Equal Power Allocation

[0105] SM-UPA: Superposition Modulation with Unequal Power Allocation

[0106] SM-GPA: Superposition Modulation with Grouped Power Allocation

[0107] 5G New Radio LDPC Codes

[0108] One of the key components of the 5G NR standard is the use of advanced error correction codes, such as LDPC codes, to ensure reliable transmission over radio channels. 5G must support high throughput up to 20 Gbps and various block sizes with different code rates for data channels and Hybrid Automatic Retransmission Requests (HARQ).

[0109] LDPC codes provide a good solution to meet all these requirements specified by 3GPP. According to 3GPP TS 38.212, the base graph of 5G NR LDPC codes is structured, and the parity-check matrix can efficiently support HARQ and rate compatibility. These features of the base graph enable support for any amount of transmitted information bits over a wide range with various code rates.

[0110] (Base Graphs of 5G NR LDPC Codes)

[0111] 3GPP TS 38.212 defines two types of base graphs (BGs), BG-1 and BG-2, respectively. The use of these BGs is determined by the required information bit size and code rate. BG-1 has 46 rows and 68 columns, and the information block size is K=22Zc. On the other hand, BG-2 has 42 rows and 52 columns, and K=10Zc. Here, Zc represents the size of the lifting matrix, and the set of lifting sizes defined in 5G NR is shown in Table 1. Table 1 shows the set of 5G NR LPDC lifting sizes.

[0112]

[0113]

[0114] Figure 5 illustrates the structure of a base graph in 5G NR. Table 2 illustrates the structure of a base graph in 5G NR.

[0115] Both BG-1 and BG-2 have the same block structure. The columns consist of information columns, core parity columns, and extension parity columns. The rows are divided into core-check rows and extension-check rows.

[0116]

[0117]

[0118] The sub-matrix E is a dual diagonal matrix, which is advantageous for enabling low-complexity encoding of 5G NR LDPC. For each base graph, there are 51 lifting sizes, ranging from 2 to 384.

[0119] According to the LDPC encoding procedure, 66Zc (for BG-1) coded bits are generated and 50Zc (for BG-2) coded bits are generated. In BG-1 and BG-2, the coded bits are output in the order of systematic bits, core parity bits, and extended parity bits.

[0120] (Rate Matching in 5G NR LDPC Codes)

[0121] N coded bits generated according to the LDPC encoding procedure are subjected to a rate matching process to select G coded bits in order to match the size of the resources allocated to the transport block transmission and the modulation order. The coded bits generated for the rate matching process are stored in a circular buffer, and the initial bit location of the coded bits to be transmitted is selected based on the redundancy version (RV) index of the HARQ. Table 3 shows the starting positions of different redundancy versions.

[0122]

[0123]

[0124] (Interleaving in 5G NR LDPC Codes)

[0125] In high-order QAM modulation schemes of 16QAM (order 4) or higher, the transmission reliability for each bit of the n-bit tuple determining the QAM symbol varies depending on the bit position. Generally, Gray mapping is applied so that the MSB has higher reliability than the LSB. Figure 6 shows an example of a 16QAM interleaver. In the 16QAM modulation case, LDPC codeword code bits are written row by row starting from row 1, and the output of the block interleaver is read column by column starting from the left column and transmitted after 16QAM modulation. Therefore, the code bits mapped to rows 1 and 2 are located at the MSB of the 4-bit tuple determining the 16QAM symbol, allowing for more reliable transmission of the Gray-mapped QAM symbol. This operation ensures that systematic bits, which have higher priority among the LDPC code bits, are transmitted more reliably.

[0126] (Layer mapping in 5G NR)

[0127] In MIMO 2 codeword transmission, each layer is divided into two sets, and data is transmitted via an independent MCS for each set. That is, a separate TB is allocated for each layer set, and independent codewords are transmitted for each layer set after channel encoding. Table 4 shows the codeword-to-layer mapping relationships for spatial multiplexing. In Table 4, a single codeword is transmitted at ranks below 4. In this case, modulation symbols are mapped alternately across each layer to maximize diversity gain.

[0128]

[0129]

[0130] 5G New Radio Modulation Mapper

[0131] A modulation mapper takes binary digits 0 or 1 as input and generates complex-valued modulation symbols as output.

[0132] (π / 2-BPSK)

[0133] In the case of π / 2-BPSK modulation, bit is a complex-valued modulated symbol according to Equation 1 It is mapped to.

[0134]

[0135] (BPSK)

[0136] In the case of BPSK modulation, bit is a complex value modulation symbol as in mathematical equation 2 It is mapped to.

[0137]

[0138] (QPSK)

[0139] In the case of QPSK modulation, bit pair is a complex-valued modulated symbol according to Equation 3 It is mapped to.

[0140]

[0141] (16QAM)

[0142] In the case of 16QAM modulation, four bits The set of bits consisting of is a complex-valued modulated symbol according to Equation 4 It is mapped to.

[0143]

[0144] (64QAM)

[0145] In the case of 64QAM modulation, six bits The bit set consisting of is a complex-valued modulated symbol according to Equation 5 It is mapped to.

[0146]

[0147] (256QAM)

[0148] In the case of 256QAM modulation, eight bits The set of bits consisting of is a complex-valued modulated symbol according to Equation 6 It is mapped to.

[0149]

[0150] (1024QAM)

[0151] In the case of 1024QAM modulation, 10 bits The set of bits consisting of is a complex-valued modulated symbol according to Equation 7 It is mapped to.

[0152]

[0153] The present disclosure proposes a method for mapping forward error correction (FEC) coded bits by considering their priority when applying superposition modulation (SM) to 5G NR, 6G, etc. SM is a modulation scheme that obtains passive shaping gain by superimposing bits transmitted in a modulation symbol after bipolar signal mapping. Taking NR LDPC as an example, FEC coded bits have priority in the order of systematic bits, core parity bits, and extended parity bits. The present disclosure can improve FEC decoding performance at the receiver by setting the power of the superimposed bipolar signals differently according to priority when transmitting FEC coded bits via SM.

[0154] The following description is based on the case where the code bits of a single code block are ordered according to priority in the order of system bits, core parity bits, and extended parity bits, using LDPC Code and / or QAM as examples. However, the method of the present disclosure can also be applied to channel coding and / or non-systematic channel coding methods other than LDPC Code, by performing ordering / arrangement according to priority. Furthermore, the method of the present disclosure can be applied even in high-order modulation methods with gray mapping other than QAM, where the reliability of each bit position of the m-bit tuple determining the modulation symbol is different.

[0155] The present disclosure proposes a method to improve decoding performance at a receiver by mapping FEC code bits to layers of SM symbols according to their priorities when FEC core bits each have different priorities.

[0156] In the following disclosure, the term 'group' may be used interchangeably with the terms 'layer group', 'SM group', and 'SM-GPA group'. Additionally, in the present disclosure, the term 'layer' may be used interchangeably with the term 'SM layer'. Furthermore, in the present disclosure, the term 'FEC code bit' may be used interchangeably with the term 'code bit'.

[0157] Additionally, in the present disclosure, a code bit may mean a codeword, a channel-coded bit(s), a rate-matched bit(s), a scrambled bit(s), or a bit included therein. And / or, a code bit may mean a bit(s) included as a result of channel coding, a result of rate matching, or a result of scrambling, or a bit included therein.

[0158] In the following disclosure, code bit priority and superposition modulation (SM) are first examined, and then a method for mapping SM layers according to code bit priority is described.

[0159] 1) Priority of FEC code bits

[0160] FEC code bits can be prioritized based on the extent to which an error in each bit affects the decoding performance of the entire FEC code block. For example, in the case of NR LDPC, system bits have a greater impact on overall FEC decoding performance than parity bits. Furthermore, even among the same system bits or parity bits, high-degree bits have a greater impact on FEC decoding performance compared to low-degree bits.

[0161] Therefore, when transmitting these FEC code bits in parallel across multiple transmission channels simultaneously, if the quality of each transmission channel is not uniform, the overall FEC decoding performance can be improved by transmitting bits that significantly affect FEC decoding performance (high priority bits) through a high-quality channel to increase the probability of successful reception.

[0162] Table 5 is an example of priority setting for NR LDPC Code. In this case, Systematic bits can be set to priority 1 (High priority), Core parity bits to priority 2 (Mid priority), and Extended Parity bits to priority 3 (Low priority). Hereinafter, the present disclosure has focused on classifying / setting code bits into three priorities as shown in Table 5, but this is merely for convenience of explanation, and it goes without saying that the embodiments described below can also be applied to code bits classified into two or four or more priorities.

[0163]

[0164]

[0165] 2) Superposition Modulation (SM)

[0166] Superposition modulation (SM) is a method that indirectly obtains shaping gain by forming a modulation symbol by overlapping multiple bit streams (layers).

[0167] Figure 7 illustrates the structure of an SM transmitter. The transmission formula for a typical SM is given by Equation 8.

[0168]

[0169] Here, x is the overlapping modulation symbol (or final modulation symbol), N is the (total) number of layers, is a power-scaled modulation symbol (or power-scaled layer symbol), is BPSK modulation symbol, is the weight of each layer, can be binary data ({0, 1}) of each layer.

[0170] In mathematical formula 8 is a parameter that sets the power value of each layer, and the method of allocating power to each layer in SM is as follows.

[0171] (a) Equal Power Allocation (EPA) (or SM-EPA)

[0172] SM-EPA is a method that allocates the same power to all layers. For example, It can be equal to mathematical formula 9. Here, N is the total number of layers.

[0173]

[0174] (b) Unequal Power Allocation (UPA) (or SM-UPA)

[0175] SM-UPA is a method of allocating different power to each layer. For example, can be equal to mathematical equation 10. Here, can be a power coefficient.

[0176]

[0177] (c) Grouped Power Allocation (GPA) (or SM-GPA)

[0178] SM-GPA is a method that groups layers into several groups and allocates different power to each group. For example, It can be equal to mathematical formula 11.

[0179]

[0180] Here, x is the overlapping modulation symbol (or final modulation symbol), L is the number of groups, and l is the index of the group. is the (power) weight of the group, G is the size of the group, is the BPSK symbol of layer g of group l, and N can be the total number of layers. And / or, is, can be a scalar for limiting symbol energy. Here, the number of groups may refer to the number of different power levels, and the size of a group may refer to the number of layers contained within a single group.

[0181] 3) SM layer mapping method based on the priority of FEC code bits

[0182] When viewing each layer in SM as a transmission channel, assigning different power levels to each layer can be seen as establishing different reliability levels for each layer. In other words, a layer assigned high power can be viewed as a highly reliable channel, while a layer assigned low power can be viewed as a lowly reliable channel. Therefore, when applying SM to FEC code bits, the decoding performance of FEC code blocks can be significantly improved by assigning high-priority bits to the high-power layer and low-priority bits to the low-power layer.

[0183] Below, we will examine in detail the layer mapping method in the following order: a method of mapping to groups considering the priority of code bits and setting different group sizes for each power level (Example 1); a method of setting the group size based on the number of code bits (Example 2); a method of resolving ambiguity when the group size is not an integer (Example 3); a method of giving different power ratios between layers within a group for each group (Example 4); a method of using two power ratios between adjacent layers by assigning power coefficients to each layer of SM (Example 5); and a method of applying SM-EPA while varying the number of layers applied to each RE according to the priority of code bits (Example 6).

[0184] (Example 1)

[0185] This embodiment proposes a method of mapping to groups considering the priority of code bits and setting different group sizes for each power level.

[0186] (a) Group mapping based on code bit priority

[0187] For example, if the priority of the NR LDPC code bits is set to three as shown in Table 5, the number of levels L of the SM-GPA in Equation 11 can be set to 3. Then, the system bits can be assigned / mapped / set to group 1, which has the highest power, the core parity bits to group 2, and the extended parity bits to group 3.

[0188] Table 6 is an example of mapping between SM-GPA groups and code bit priorities. In Table 6, SM-GPA groups 1, 2, and 3 represent groups 1, 2, and 3, respectively, and Channel Reliability may represent a power level. For example, if Channel Reliability is high, it may be a high power level. That is, as shown in Table 6, code bits of high priority can be assigned / mapped / set to SM-GPA groups with high power levels.

[0189]

[0190]

[0191] (b) Setting different group sizes by power level

[0192] In Equation 11, the group size for each power level is the same as G. Therefore, when code bits are allocated for each power level, the number of code bits for each priority may need to be the same. However, since the number of code bits for each priority generally differs, a method is required to map FEC code bits to each (layer) group of SM-GPA. In this disclosure, the term 'code bit' may be used interchangeably with the term 'FEC code bit'. In this disclosure, the term 'group' may be replaced with the terms 'layer group' and 'SM group'.

[0193] For example, there is a method to set different group sizes for each power level as in Equation 12. That is, the (overlapping modulated) modulation symbol (x) can be as in Equation 12.

[0194]

[0195] Here, x is the overlapping modulation symbol (or final modulation symbol), L is the number of groups, and l is the index of the group. is the group's (power) weight, is the size of group l, is the BPSK modulation symbol of layer g belonging to group l, and N can be the total number of layers. Also, And, can be a scalar for limiting symbol energy. Here, the number of groups may refer to the number of different power levels, and the size of the group may refer to the number of layers the group contains.

[0196] (Example 2)

[0197] This embodiment proposes a method for setting the size of a group based on the number of code bits.

[0198] For example, in an NR LDPC with three priorities as shown in Table 5, if the number of priority 1 bits is 600 bits, the number of priority 2 bits is 200 bits, and the number of priority 3 bits is 400 bits, and the number of transmitted bits per resource element (RE) is 6 bits, the number of levels (or groups) L ​​of the SM-GPA can be set to 3. In this case, system bits can be assigned / mapped / set to Group 1, which has the highest power, core parity bits to Group 2, and extended parity bits to Group 3. And / or, the size of each group is proportional to the number of corresponding priority bits and It can be set to.

[0199] (Example 3)

[0200] This embodiment proposes a method to resolve ambiguity when the group size is not an integer.

[0201] In Example 2, the group size for each power level was set to an integer, but it is more common for the group size to be non-integer. For example, in an NR LDPC with three priorities as shown in Table 5, if the LDPC encoder input data size is 4000 bits and the code rate is 0.5, the lifting size Zc = 192, and accordingly, the number of priority 1 bits (e.g., system bits) can be 20*Zc = 3840 bits, the number of priority 2 bits (e.g., core parity bits) can be 4*Zc = 768 bits, and the number of priority 3 bits (e.g., extended parity bits) can be 42*Zc = 8064 bits. That is, the total FEC bits are 12672 bits, the number of transmitted bits per RE is 6 bits when transmitting 64QAM, and the total number of REs can be 12672 / 6 = 2112.

[0202] At this time, the size of each group proportional to the number of corresponding priority bits is and This is the case. In this case, since the group size is not an integer, a more general rule is needed to place each priority bit in RE.

[0203] (a) Bit group mapping when the group size according to Example 2 is a non-integer real number

[0204] FIG. 8 illustrates a block memory structure for assigning FEC code bits to overlapping modulation symbols.

[0205] For example, as shown in FIG. 8, a block memory can be configured such that the number of columns is the number of REs and the number of rows is the modulation order (or the number of bits per symbol / RE according to the modulation order). And / or, bits with priority 1 (i.e., priority 1 bits) can be written to the memory row by row first, and after all bits with priority 1 are written, bits with priority 2 and bits with priority 3 can be written to the memory row by row. And / or, after all bits are written, the memory can be read in the column direction to generate SM symbols. At this time, the bits of each column can be assigned sequentially to groups 1 through N. For example, if bits with priority 1 are written to rows 1 through 3, bits with priority 2 are written to rows 4 through 5, and bits with priority 3 are written to rows 6 through 7, rows 1 through 3 can be assigned to group 1, rows 4 through 5 to group 2, and rows 6 through 7 to group 3.

[0206] (b) Calculate group size

[0207] When grouping using this block memory structure, the group size can be set through the following calculation process.

[0208]

[0209] For example, the initial group size of each group Based on, setting group size can be determined. Here, i can be an integer between 1 and N, and N can represent the total number of groups. Specifically, the cumulative error as the initial value. can be set to 0. Subsequently, group size settings can be performed sequentially from the first group to the Nth group.

[0210] For example, for the i-th group, cumulative error a is the initial group size of the i-th group If smaller, the setting group size of the i-th group Is It can be determined by the ceiling value. That is, the actual configuration group size Is It can be set as. The configured group size is calculated through the ceil operation, allowing the initial group size to be reflected while maintaining the sum of the group sizes. And, the configured group size of the i-th group After it is determined, cumulative error is the existing accumulated error Set group size and initial group size It can be updated by adding the error / difference values. In other words, the accumulated error Is It can be updated to.

[0211] On the other hand, cumulative error a is the initial group size of the i-th group If above, the setting group size of the i-th group can be set to 0. In this case, cumulative error is the existing accumulated error Initial group size It can be updated with the value obtained by subtracting . In other words, the accumulated error Is It can be updated to.

[0212] This process is repeated for all groups, thereby determining the set group size corresponding to the initial group size of each group.

[0213] Therefore, the size of each setting group can be set in integer units using a block memory structure, while also being adjusted to reflect the distribution of the initial group size overall. In other words, errors occurring during the group size setting process can be reflected in the process of determining the group size of subsequent groups through accumulated errors.

[0214] If you calculate the size of each group using the above calculation process, It can be like this.

[0215] FIG. 9 is an example of allocating / setting / mapping FEC code bits to a block memory according to Embodiment 3. Referring to FIG. 9, each column corresponds to an SM symbol, and each row may be a layer or a bit corresponding to a layer. For example, the first, second layer, or corresponding bit is a group Included in, and the third layer or corresponding bit is a group It is included in, and the fourth to sixth layers or corresponding bits are group It can be included in.

[0216] (c) Different power allocations within the same group

[0217] In SM-GPA, layers within a group all have the same power, which can lead to ambiguity issues. For example, in a group of size 2, the layers {1,-1} and {-1,1} are mapped to 1+(-1)=(-1)+1=0, even though they are different data. In other words, there is a problem in that the overlap of BPSK modulation symbol 1 in the first layer and BPSK modulation symbol -1 in the second layer within the same group is difficult to distinguish from the overlap of BPSK modulation symbol -1 in the first layer and BPSK modulation symbol 1 in the second layer.

[0218] This ambiguity problem can be resolved by using FEC redundancy, but it can also be resolved by differentiating the power of layers within the same group by a unit smaller than the power difference between groups. This method of power allocation by group and / or layer can be resolved by assigning / setting / mapping different power to different layers within the same group, as shown in Equation 13.

[0219]

[0220] Here, x is the overlapping modulation symbol (or final modulation symbol), L is the number of groups, and l is the index of the group. is the inter-group coefficient, and is a scalar for symbol energy limiting, is the size of the l-th group, is the intra-group coefficient, is a scalar for symbol energy limiting, is the intra-group power ratio ), can be a BPSK modulation symbol of layer g belonging to group l.

[0221] in other words, is a coefficient for allocating power between different layer groups, and is a coefficient for allocating power to each layer within the same layer group. At this time Power allocation between layers within the same group can vary depending on the value.

[0222] for example, can be a value less than 1. And / or It can be set to a value less than 1 but sufficiently close to 1. For example, can be greater than or equal to 0.9 and less than or equal to 0.999. In this case, because the power of the layers is different, even if layers within the same group overlap, the ambiguity problem where different data correspond to a single symbol is prevented, and the performance gap between layers within the same group can be minimized by minimizing the power difference between layers belonging to the same group.

[0223] Figure 10 illustrates the power per layer according to Equation 13. That is, Figure 10 shows that in Equation 13 Power parameter when ( This is an example of ). Group 1 includes Layer 1 and Layer 2, Group 2 includes Layer 3, and Group 3 includes Layers 4, 5, and 6. The x-axis of the graph in Fig. 10 is the layer index, and the y-axis is the power parameter. Referring to Fig. 10, it can be seen that Layers 1 and 2 in Group 1 and Layers 4, 5, and 6 in Group 3 each have different power within the same group, but the power difference is minimized.

[0224] (Example 4)

[0225] This embodiment proposes a method for setting the power ratio between layers within a group differently for each group.

[0226] The intra-group power ratio can be set differently for each group l as shown in Equation 14 (i.e., ).

[0227]

[0228] Here, x is the overlapping modulation symbol (or final modulation symbol), L is the number of groups, and l is the index of the group. is the size of the l-th group, is an out-of-group coefficient, and is a scalar for symbol energy limiting, and is the coefficient within the group (or the coefficient of layer g of group l), is a scalar for symbol energy limiting, may be the in-group power ratio of the l-th group (or group l) ). can be a BPSK modulation symbol of layer g belonging to group l.

[0229] FIG. 11 illustrates a block memory structure for assigning FEC code bits to SM symbols according to Example 4. FIG. 11 is an example of grouping FEC bits. That is, FIG. 11 is group 2 of FIG. 9 ( ) and Group 3( ) group 2( This is an example of grouping to apply the same power ratio (within the group). In this case, for bits with a priority of 1 in the FEC, the power change between layers within the group can be made large to eliminate modulation symbol ambiguity (i.e., Group 1), and for bits with priorities 2 and 3, they can be grouped into one group to make the power change between layers within the group small (Group 2).

[0230] FIG. 12 illustrates the power per layer according to Example 4. FIG. 12 is from Equation 13 When assigned power parameters per group and / or layer ( An example of (or power coefficient) is provided. Referring to FIG. 12, it can be seen that layers 1 and 2 of group 1 have large power changes between layers, while layers 3 to 6 of group 2 have small power changes between layers.

[0231] (Example 5)

[0232] This embodiment proposes a method of using two power ratios between adjacent layers by assigning power coefficients to each layer of SM.

[0233] If we take the existing 5G 256-QAM modulation as superposition modulation, as shown in Equation 15, the power coefficient of each layer is set so that the power ratio between adjacent layers becomes 0.5.

[0234]

[0235] Here, x is an overlapping modulation symbol (or final modulation symbol) or an I / Q (In-phase / Quadrature) data symbol (or I / Q data), N is the number of layers, is a power-scaled modulation symbol (or power-scaled layer symbol), is the weight of each layer n, is the power normalizing coefficient, is BPSK modulation symbol, can be binary data ({0, 1}) of each layer.

[0236] This embodiment proposes a method of selecting and using either p or q as a power ratio between adjacent layers as shown in Equation 16. A power coefficient can be determined / set such that when a high-priority bit is mapped and transmitted to the layer, the power ratio becomes p, and when a low-priority bit is mapped and transmitted to the layer, the power ratio becomes q.

[0237]

[0238] Here, overlapping modulation symbols (or final modulation symbols) or I / Q (In-phase / Quadrature) data symbols (or I / Q data), N is the total number of layers, is a power-scaled layer symbol, is the weight of each layer, is BPSK modulation symbol, can be the binary data ({0, 1}) of each layer. Also, is the power normalizing coefficient, and If it is a high priority and, if not It could be.

[0239] For example, if p=0.5 and q=0.9 are selected, the power difference between layers can be increased for high-priority bits to reduce ambiguity, and power efficiency can be increased for low-priority bits.

[0240] (Example 6)

[0241] This embodiment proposes a method for applying SM-EPA and setting the number of layers applied to each RE differently according to the priority of the code bits. For example, when applying SM-EPA, the number of layers applied to each RE can be varied according to the priority of the code bits.

[0242] FIG. 13 illustrates a transmitter structure according to Example 6. Referring to FIG. 13, the structure of each of superposition modulators 1 to 3 may be the same as FIG. 7. For example, REs assigned the same number of layers to each other may be defined or referred to as SM-REG (Resource Element Group).

[0243] At this time, if we take an NR LDPC with three priorities as shown in Table 5, the bits with priority 1 (Priority 1 bits) can be assigned / mapped / set to SM-REG 1 with 2 layers, the bits with priority 2 (Priority 2 bits) can be assigned / mapped / set to SM-REG 2 with 4 layers, and the bits with priority 3 (Priority 3 bits) can be assigned / mapped / set to SM-REG 3 with 6 layers.

[0244] That is, bits with priority 1 can be superimposed modulated based on 2 layers by superimposed modulator 1, bits with priority 2 can be superimposed modulated based on 4 layers by superimposed modulator 2, and bits with priority 3 can be superimposed modulated based on 6 layers by superimposed modulator 3. And / or, bits with priority 1 can be assigned / mapped to SM-REG 1 as superimposed modulated symbols, bits with priority 2 can be assigned / mapped to SM-REG 2 as superimposed modulated symbols, and bits with priority 3 can be assigned / mapped to SM-REG 3 as superimposed modulated symbols.

[0245] Table 7 illustrates the mapping between the SM-REG of SM-EPA and the priority of code bits. That is, code bits can be assigned / mapped / set to fewer layers and SM-REGs as their priority increases. Through this, the present disclosure can improve decoding performance.

[0246]

[0247]

[0248] FIG. 14 is a flowchart illustrating a method of operation of a device according to one embodiment of the present disclosure. Herein, the device may include a terminal and / or a base station.

[0249] Referring to FIG. 14, the device may generate coded bits (coded bit(s)) by applying channel coding to a transmission block in step S1410. For example, the channel coding may be FEC channel coding. For example, the FEC channel coding may be the LDPC channel coding described above.

[0250] Next, in step S1420, the device can generate modulation symbols (e.g., SM symbols) by performing superposition modulation (SM) based on layer groups on the code bits.

[0251] For example, layer groups may have different power levels. And / or, code bits may be mapped to one of the layer groups based on priority. And / or, the size of the layer groups may be set based on the ratio of the number of code bits mapped to the layer groups.

[0252] For example, assuming the case where the code bits are classified into priority 1 to 3 as shown in Table 5 and the first to third layer groups, the code bits with priority 1 can be mapped to the first layer group, the code bits with priority 2 can be mapped to the second layer group, and the code bits with priority 3 can be mapped to the third layer group. In this case, if the ratio of the number of mapped code bits in the first to third layer groups is 3:1:2 and the total number of layers is 6, the size of the first layer group can be set to 3=6*3 / 6, the size of the second layer group to 1=6*1 / 6, and the size of the third layer group to 2=6*2 / 6.

[0253] For example, code bits can be mapped to layer groups with higher power levels as their priority increases. For example, a first layer group mapped to a code bit with priority 1 corresponds to the highest power level, a third layer group mapped to a code bit with priority 3 corresponds to the lowest power level, and a second layer group mapped to a code bit with priority 2 corresponds to a power level between the power level of the first layer group and the power level of the third layer group.

[0254] For example, based on the ratio of the number of code bits mapped to the layer groups, the size of at least one of the layer groups is a real number rather than an integer, and the size of the layer groups can be set based on a block memory (or block memory structure) (e.g., the block memory (structure) of FIG. 8) having a number of columns associated with resource elements (RE) and a number of rows associated with modulation orders. For example, and / or, code bits can be written to the block memory one row at a time in order of priority, and / or, bits of each column can be mapped to one of the layer groups in order. And / or, modulation symbols (e.g., SM symbols) can be generated by reading from the block memory one column at a time in order.

[0255] And / or, based on the fact that the size of at least one of the layer groups based on the ratio of the number of code bits mapped to the layer groups is a non-integer real number, the size of the layer groups has an integer value according to the operation process of Example 3 described above, and the accumulated error ( It can be set based on ).

[0256] And / or, each of the layer groups includes one or more layers, and each of the one or more layers within the same layer group may have different power levels based on the intra-group power ratio. For example, power allocation for layers within the same or different layer groups may follow Equation 13. In this case, the intra-group power ratio may be a value less than 1.

[0257] For example, the intra-group power ratio can be applied differently for each layer group. In this case, two or more layer groups can be grouped so that the same power ratio is applied.

[0258] For example, each layer can be assigned different power without layer groups. For example, each layer can be assigned power according to Equation 16. For example, the weights assigned to each layer ( ) is the power factor assigned / applied when the priority of the code bit (or binary data of each layer) is higher than / exceeds the preset priority (or has a higher priority). and, if not, It could be.

[0259] For example, the number of layers applied to each RE can be mapped / assigned / set differently depending on the priority of the code bits. For instance, code bits can be mapped to the RE by nested modulation based on a nested modulator with fewer layers as their priority increases.

[0260] Operations based on the above-described S1410 to S1420 can be implemented by the wireless device (200) of FIG. 3. For example, referring to FIG. 3, the wireless device (200) can control at least one memory (204) and / or at least one transceiver (206) to perform operations based on S1410 to S1420.

[0261] The method of operation of the device described with reference to FIG. 14 is identical to the operation and embodiments described with reference to FIG. 1 to 13, so further detailed description is omitted. The method of operation of the device of FIG. 14 may be changed / replaced / added with all and / or part of the embodiments / examples of FIG. 1 to 13, or a combination thereof.

[0262] The operations / terms based on the embodiments described above are described under the assumption of an existing system (e.g., a 5G system). However, this is for the convenience of explanation and is not intended to limit the scope of application of the technical problems and means for solving problems that are to be solved by this disclosure to a specific system. That is, the technical problems / technical issues / problems mentioned in this disclosure may exist in other systems (e.g., a 6G system) as well. It is evident that the embodiments of this disclosure can be extended to solve problems that exist in other systems as well. Therefore, for the extended application of the embodiments of this disclosure to other systems, terms defined / described based on a 5G system may be replaced / changed with terms defined in other systems (or generalized terms not specific to one system).

Claims

1. In a method performed by a terminal, A step of generating code bits by applying channel coding to a transmission block; and The method includes the step of generating a modulation symbol by performing nested modulation based on layer groups on the above code bit, The above layer groups have different power levels, The above code bits are mapped to one of the above layer groups based on priority, and A method in which the size of the above layer groups is set based on the ratio of the number of code bits mapped to the above layer groups.

2. In Paragraph 1, A method in which the above code bits are mapped to a layer group with a higher power level as the priority increases.

3. In Paragraph 1, Based on the fact that the size of at least one of the layer groups based on the ratio of the number of code bits mapped to the layer groups is a real number rather than an integer, A method in which the sizes of the above layer groups are set based on accumulated error to have integer values.

4. In Paragraph 1, Based on the fact that the size of at least one of the layer groups based on the ratio of the number of code bits mapped to the layer groups is a real number rather than an integer, A method in which the size of the above layer groups is set based on a block memory having a number of columns related to resource elements (RE) and a number of rows related to modulation order.

5. In Paragraph 4, The above code bits are written to the above block memory one row at a time in order of priority, and A method in which the bits of each column are mapped to one of the above layer groups in order.

6. In Paragraph 5, A method in which the sizes of the above layer groups are set based on accumulated error to have integer values.

7. In Paragraph 5, The above modulation symbol is generated by reading the block memory column by column in order from the block memory.

8. In Paragraph 1, Each of the above layer groups includes one or more layers, and A method in which each of one or more layers within the same layer group has a different power level based on the power ratio within the group.

9. In Paragraph 8, A method in which the power ratio within the above group is a value less than 1.

10. In the terminal, One or more transmitters and receivers; One or more processors; and It includes one or more memories connected to the above one or more processors and storing instructions, A terminal that enables the terminal to perform all steps of the method according to any one of claims 1 through 9, based on the above instructions being executed by the one or more processors.

11. A device comprising one or more memories and one or more processors connected to the one or more memories, The above one or more memories are a device that stores instructions for the device to perform all steps of the method according to any one of claims 1 to 9, based on execution by the above one or more processors.

12. In a non-transitory computer-readable storage medium for storing instructions, The above instructions, executable by one or more processors, are a non-transient computer-readable storage medium that enables a terminal to perform all steps of the method according to any one of claims 1 through 8.

13. In a method performed by a base station, A step of generating code bits by applying channel coding to a transmission block; and The method includes the step of generating a modulation symbol by performing nested modulation based on layer groups on the above code bit, The above layer groups have different power levels, The above code bits are mapped to one of the above layer groups based on priority, and A method in which the size of the above layer groups is set based on the ratio of the number of code bits mapped to the above layer groups.

14. Regarding base stations, One or more transmitters and receivers; One or more processors; and It includes one or more memories connected to the above one or more processors and storing instructions, A base station that enables the base station to perform all steps of the method according to paragraph 13, based on the above instructions being executed by the one or more processors.

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