Apparatus and method for performing asynchronous measurement device independent quantum secure direct communication by using intermediate node in communication system

Abstract

The objective of the present disclosure is to perform asynchronous measurement device independent quantum secure direct communication (AMDI QSDC) by using an intermediate node in a communication system. The present disclosure may comprise the steps of: acquiring system information; performing an initial access procedure on the basis of the system information; transmitting a first signal for measurement to a second device; receiving information related to a measurement result from the second device; generating, on the basis of the information related to the measurement result, data signals on which data encoding has been performed; and transmitting the data signals to the second device.

Description

Device and method for performing asynchronous detector-independent quantum secure direct communication using an intermediate node in a communication system

[0001] The present disclosure relates to a communication system, and more particularly, to an apparatus and method for performing asynchronous measurement device independent quantum secure direct communication (AMDI QSDC) using an intermediate node in a communication system using an intermediate node.

[0002] Wireless access systems are widely deployed to provide various types of communication services, such as voice and data. Typically, wireless access systems are multiple access systems that support communications with multiple users by sharing available system resources (e.g., bandwidth, transmission power). Examples of multiple access systems include code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), and single-carrier frequency division multiple access (SC-FDMA).

[0003] In particular, as numerous communication devices demand greater communication capacity, enhanced mobile broadband (eMBB) communication technologies are being proposed, improving upon existing radio access technology (RAT). Furthermore, massive machine type communications (mMTC), which connects multiple devices and objects to provide diverse services anytime and anywhere, as well as communication systems that consider reliability and latency-sensitive services / user equipment (UE), are being proposed. Various technological configurations are being proposed for these solutions.

[0004] The present disclosure relates to an apparatus and method for performing asynchronous measurement device independent quantum secure direct communication (AMDI QSDC) using an intermediate node in a communication system.

[0005] The present disclosure relates to a device and method for transmitting a message using entangled qubits in a communication system.

[0006] The present disclosure relates to a device and method for transmitting a message using a valid event detected by only one of two detectors in a communication system.

[0007] The present disclosure relates to a device and method for determining whether there is an eavesdropper based on the frequency of valid events in a communication system.

[0008] The present disclosure relates to a device and method for transmitting a message using an intermediate node including a detector in a communication system.

[0009] The present disclosure relates to a device and method for transmitting a message based on a pulse position in a communication system.

[0010] The present disclosure relates to a device and method for sharing a security key based on an index pair of valid events in a communication system.

[0011] The present disclosure relates to a device and method for transmitting a message based on a phase difference in a communication system.

[0012] The present disclosure relates to a device and method for verifying an initial state of a transmitting node based on a detection result in a communication system.

[0013] The present disclosure relates to a device and method for transmitting a message using interference between two detectors in a communication system.

[0014] The present disclosure relates to a device and method for performing long-distance communication using an asynchronous detection method in a communication system.

[0015] The present disclosure relates to a device and method for performing secure communication in a communication system regardless of whether or not the detection result is eavesdropped.

[0016] The technical objectives to be achieved in the present disclosure are not limited to those mentioned above, and other technical tasks not mentioned can be considered by a person having ordinary skill in the technical field to which the technical configuration of the present disclosure is applied from the embodiments of the present disclosure described below.

[0017] As an example of the present disclosure, a method performed by a first device in a communication system, the method comprising: obtaining system information; performing an initial connection procedure based on the system information; transmitting a first signal for measurement to a second device; receiving information related to a measurement result from the second device; generating a data signal on which data encoding is performed based on the information related to the measurement result; and transmitting the data signal to the second device, wherein the information related to the measurement result includes information related to time intervals in which at least one of the qubits included in the first signal for measurement and the second signal for measurement transmitted by a third device is detected only by one of two detectors of the second device, and the data encoding can be performed based on the information related to the time intervals.

[0018] As an example of the present disclosure, a method performed by a second device in a communication system, the method comprising: obtaining system information; performing an initial connection procedure based on the system information; receiving a first signal for measurement from a first device; receiving a second signal for measurement from a third device; determining whether to interrupt communication based on the first signal for measurement and the second signal for measurement; transmitting information related to a measurement result to the first device; receiving a data signal on which data encoding is performed based on the information related to the measurement result from the first device; and transmitting a detection result of the data signal to the third device, wherein the information related to the measurement result includes information related to time intervals in which at least one of the qubits included in the first signal for measurement and the second signal for measurement is detected only by one of two detectors of the second device, and the data encoding can be performed based on the information related to the time intervals.

[0019] As an example of the present disclosure, a method performed by a third device in a communication system, comprising: obtaining system information; performing an initial connection procedure based on the system information; transmitting a second signal for measurement to a second device; receiving a detection result of a data signal transmitted by a first device from the second device; and performing data decoding based on the detection result of the data signal, wherein the decoding may be performed based on information related to time intervals in which at least one of the qubits included in the first signal for measurement and the second signal for measurement transmitted by the first device is detected by only one of two detectors of the second device.

[0020] As an example of the present disclosure, in a communication system, a first device includes a transceiver and a processor coupled to the transceiver, wherein the processor is configured to obtain system information, obtain the system information, perform an initial connection procedure based on the system information, transmit a first signal for measurement to a second device, receive information related to a measurement result from the second device, generate a data signal on which data encoding is performed based on the information related to the measurement result, and transmit the data signal to the second device, wherein the information related to the measurement result includes information related to time intervals in which at least one of the qubits included in the first signal for measurement and the second signal for measurement transmitted by a third device is detected only by one of two detectors of the second device, and the data encoding can be performed based on the information related to the time intervals.

[0021] As an example of the present disclosure, in a communication system, a second device includes a transceiver and a processor connected to the transceiver, wherein the processor is configured to obtain system information, perform an initial connection procedure based on the system information, receive a first signal for measurement from a first device, receive a second signal for measurement from a third device, determine whether to interrupt communication based on the first signal for measurement and the second signal for measurement, transmit information related to a measurement result to the first device, receive a data signal on which data encoding is performed based on the information related to the measurement result from the first device, and transmit a detection result of the data signal to the third device, wherein the information related to the measurement result includes information related to time intervals in which at least one of the qubits included in the first signal for measurement and the second signal for measurement is detected only by one of two detectors of the second device, and the data encoding can be performed based on the information related to the time intervals.

[0022] As an example of the present disclosure, in a communication system, a third device includes a transceiver and a processor connected to the transceiver, wherein the processor is configured to obtain system information, perform an initial connection procedure based on the system information, transmit a second signal for measurement to a second device, receive a detection result of a data signal transmitted by a first device from the second device, and perform data decoding based on the detection result of the data signal, wherein the decoding may be performed based on information related to time intervals in which at least one of the qubits included in the first signal for measurement transmitted by the first device and the second signal for measurement is detected only by one of two detectors of the second device.

[0023] As an example of the present disclosure, a first communication device includes at least one processor, and at least one computer memory connected to the at least one processor and storing instructions that direct operations when executed by the at least one processor, the operations including: obtaining system information; performing an initial connection procedure based on the system information; transmitting a first signal for measurement to a second communication device; receiving information related to a measurement result from the second communication device; generating a data signal on which data encoding is performed based on the information related to the measurement result; and transmitting the data signal to the second communication device, wherein the information related to the measurement result includes information related to time intervals in which at least one of the qubits included in the first signal for measurement and the second signal for measurement transmitted by the third communication device is detected only by one of two detectors of the second communication device, and the data encoding can be performed based on the information related to the time intervals.

[0024] As an example of the present disclosure, a non-transitory computer-readable medium storing at least one instruction, the at least one instruction being executable by a processor, the at least one instruction configuring a first device to obtain system information, perform an initial connection procedure based on the system information, transmit a first signal for measurement to a second device, receive information related to a measurement result from the second device, generate a data signal on which data encoding is performed based on the information related to the measurement result, and transmit the data signal to the second device, wherein the information related to the measurement result includes information related to time intervals in which at least one of the qubits included in the first signal for measurement and the second signal for measurement transmitted by a third device is detected only by one of two detectors of the second device, and the data encoding can be performed based on the information related to the time intervals.

[0025] The above-described aspects of the present disclosure are only some of the preferred embodiments of the present disclosure, and various embodiments reflecting the technical features of the present disclosure can be derived and understood by a person having ordinary skill in the art based on the detailed description of the present disclosure to be described below.

[0026] The following effects may be achieved by embodiments based on the present disclosure.

[0027] According to the present disclosure, efficient quantum communication can be performed using an intermediate node including a detector.

[0028] The effects that can be obtained from the embodiments of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those skilled in the art to which the technical configuration of the present disclosure is applied, from the description of the embodiments of the present disclosure below. In other words, unintended effects resulting from implementing the configuration described in the present disclosure can also be derived from the embodiments of the present disclosure by those skilled in the art.

[0029] The accompanying drawings are intended to aid understanding of the present disclosure and, together with detailed descriptions, may provide embodiments of the present disclosure. However, the technical features of the present disclosure are not limited to specific drawings, and the features disclosed in each drawing may be combined with each other to form new embodiments. Reference numerals in each drawing may indicate structural elements.

[0030] Figure 1 illustrates an example of a communication system applicable to the present disclosure.

[0031] FIG. 2 illustrates an example of a wireless device applicable to the present disclosure.

[0032] FIG. 3 illustrates a method for processing a transmission signal applicable to the present disclosure.

[0033] Figure 4 illustrates a communication procedure between a terminal and a base station applicable to the present disclosure.

[0034] FIG. 5 illustrates an example of a communication structure that can be provided in a 6G (6th generation) system applicable to the present disclosure.

[0035] Figure 6 illustrates an electromagnetic spectrum applicable to the present disclosure.

[0036] Figure 7 illustrates a transmitter structure applicable to the present disclosure.

[0037] Figure 8 illustrates an example of a functional framework for application of artificial intelligence technology applicable to the present disclosure.

[0038] Figure 9 illustrates an example of a procedure for utilizing an artificial intelligence model applicable to the present disclosure.

[0039] Figure 10 illustrates a communication procedure based on AI (artificial intelligence) technology applicable to the present disclosure.

[0040] Figure 11 illustrates three basic properties of quantum information that can be utilized in information communication applicable to the present disclosure.

[0041] FIG. 12 illustrates an example of a quantum transmission protocol according to one embodiment of the present disclosure.

[0042] FIG. 13 illustrates an example of a procedure for transmitting quantum information in a two-step quantum secure direct communication according to one embodiment of the present disclosure.

[0043] FIG. 14 illustrates an example of a transmitting node transmitting a data signal using the AMDI QSDC protocol according to one embodiment of the present disclosure.

[0044] FIG. 15 illustrates an example of a receiving node receiving a data signal using the AMDI QSDC protocol according to one embodiment of the present disclosure.

[0045] FIG. 16 illustrates an example in which an intermediate node supports the AMDI QSDC protocol according to one embodiment of the present disclosure.

[0046] FIG. 17 illustrates an example of a structure of nodes for transmitting or receiving a signal for measurement according to one embodiment of the present disclosure.

[0047] FIG. 18 illustrates an example of a procedure in which a transmitting node transmits data based on the pulse position of a photon according to one embodiment of the present disclosure.

[0048] FIG. 19 illustrates an example of a structure of nodes for transmitting a data signal using a phase difference according to one embodiment of the present disclosure.

[0049] FIG. 20 illustrates an example of a procedure of AMDI QSDC according to one embodiment of the present disclosure.

[0050] FIG. 21 illustrates an example of a valid time interval according to one embodiment of the present disclosure.

[0051] FIG. 22 illustrates an example of signaling for determining a valid index pair based on a signal for measurement according to one embodiment of the present disclosure.

[0052] FIG. 23 illustrates an example of signaling for transmitting data based on pulse position according to one embodiment of the present disclosure.

[0053] FIG. 24 illustrates an example of signaling for transmitting data based on a phase difference according to one embodiment of the present disclosure.

[0054] Figure 25 illustrates an example of a wireless device applicable to the present disclosure.

[0055] Figure 26 illustrates an example of a portable device applicable to the present disclosure.

[0056] FIG. 27 illustrates an example of a vehicle or autonomous vehicle applicable to the present disclosure.

[0057] Figure 28 illustrates an example of a vehicle applicable to the present disclosure.

[0058] FIG. 29 illustrates an example of an XR device applicable to the present disclosure.

[0059] Figure 30 illustrates an example of a robot applicable to the present disclosure.

[0060] Figure 31 illustrates an example of an AI device applicable to the present disclosure.

[0061] Figure 32 illustrates an example of a quantum communication device applicable to the present disclosure.

[0062] The following embodiments combine the components and features of the present disclosure in a predetermined form. Each component or feature may be considered optional unless explicitly stated otherwise. Each component or feature may be implemented without being combined with other components or features. Furthermore, some components and / or features may be combined to form embodiments of the present disclosure. The order of operations described in the embodiments of the present disclosure may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment.

[0063] In the description of the drawings, procedures or steps that may obscure the gist of the present disclosure are not described, and procedures or steps that can be understood by a person skilled in the art are also not described.

[0064] Throughout the specification, when a part is said to "comprising" or "including" a component, this does not mean that other components may be included, but rather that other components may be excluded, unless otherwise specifically stated. In addition, terms such as "...part," "...unit," and "module" described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware, software, or a combination of hardware and software. In addition, the words "a" or "an," "one," "the," and similar related words may be used in the context of describing the present disclosure (especially in the context of the claims below) to include both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context.

[0065] Embodiments of the present disclosure described herein focus on the data transmission and reception relationship between a base station and a mobile station. Here, the base station is understood as a terminal node of a network that directly communicates with the mobile station. Certain operations described herein as being performed by the base station may, in some cases, be performed by an upper node of the base station.

[0066] That is, in a network consisting of multiple network nodes including a base station, various operations performed for communication with a mobile station may be performed by the base station or other network nodes other than the base station. In this case, the term 'base station' may be replaced by terms such as fixed station, Node B, eNB (eNode B), gNB (gNode B), ng-eNB, advanced base station (ABS), or access point.

[0067] Additionally, in the embodiments of the present disclosure, the term terminal may be replaced with terms such as user equipment (UE), mobile station (MS), subscriber station (SS), mobile subscriber station (MSS), mobile terminal, or advanced mobile station (AMS).

[0068] Additionally, a transmitter refers to a fixed and / or mobile node that provides data or voice services, and a receiver refers to a fixed and / or mobile node that receives data or voice services. Therefore, for uplink, a mobile station can be the transmitter, and a base station can be the receiver. Similarly, for downlink, a mobile station can be the receiver, and a base station can be the transmitter.

[0069] Embodiments of the present disclosure may be supported by standard documents disclosed in at least one of wireless access systems, such as IEEE 802.xx system, 3rd Generation Partnership Project (3GPP) system, 3GPP Long Term Evolution (LTE) system, 3GPP 5th generation (5G) NR (New Radio) system and 3GPP2 system, and in particular, embodiments of the present disclosure may be supported by 3GPP TS (technical specification) 38.211, 3GPP TS 38.212, 3GPP TS 38.213, 3GPP TS 38.321 and 3GPP TS 38.331 documents.

[0070] Furthermore, the embodiments of the present disclosure can be applied to other wireless access systems and are not limited to the systems described above. For example, they can be applied to systems implemented after the 3GPP 5G NR system and are not limited to a specific system.

[0071] That is, obvious steps or parts not described in the embodiments of the present disclosure can be explained by referring to the above documents. In addition, all terms disclosed in this document can be explained by the above standard documents.

[0072] Hereinafter, preferred embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description set forth below, together with the accompanying drawings, is intended to illustrate exemplary embodiments of the present disclosure and is not intended to represent the only embodiments in which the technical configurations of the present disclosure may be implemented.

[0073] Additionally, specific terms used in the embodiments of the present disclosure are provided to aid in understanding of the present disclosure, and the use of such specific terms may be changed to other forms without departing from the technical spirit of the present disclosure.

[0074] The following technology can be applied to various wireless access systems such as CDMA (code division multiple access), FDMA (frequency division multiple access), TDMA (time division multiple access), OFDMA (orthogonal frequency division multiple access), and SC-FDMA (single carrier frequency division multiple access).

[0075]

[0076] For clarity, the following description is based on 3GPP communication systems (e.g., LTE, NR, etc.), but the technical spirit of the present disclosure is not limited thereto. LTE may refer to technology after 3GPP TS 36.xxx Release 8. Specifically, LTE technology after 3GPP TS 36.xxx Release 10 may be referred to as LTE-A, and LTE technology after 3GPP TS 36.xxx Release 13 may be referred to as LTE-A pro. 3GPP NR may refer to technology after TS 38.xxx Release 15. 3GPP 6G may refer to technology after TS Release 17 and / or Release 18. "xxx" refers to a standard document detail number. LTE / NR / 6G may be collectively referred to as a 3GPP system.

[0077] For background information, terms, abbreviations, etc. used in this disclosure, reference may be made to standard documents published prior to this disclosure. For example, reference may be made to standard documents 36.xxx and 38.xxx.

[0078]

[0079] Communication system applicable to the present disclosure

[0080] Although not limited thereto, the various descriptions, functions, procedures, proposals, methods and / or operational flowcharts of the present disclosure disclosed in this document may be applied to various fields requiring wireless communication / connectivity (e.g., 5G) between devices.

[0081] Hereinafter, more specific examples will be provided with reference to the drawings. In the drawings / descriptions below, the same drawing reference numerals may represent identical or corresponding hardware blocks, software blocks, or functional blocks, unless otherwise described.

[0082] Figure 1 illustrates an example of a communication system applied to the present disclosure.

[0083] Referring to FIG. 1, a communication system (100) applied to the present disclosure includes a wireless device, a base station, and a network. Here, the wireless device refers to a device that performs communication using a 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 device. Although not limited thereto, the wireless device may include a robot (100a), a vehicle (100b-1, 100b-2), an XR (extended reality) device (100c), a hand-held device (100d), a home appliance (100e), an IoT (Internet of Things) device (100f), and an AI (artificial intelligence) device / server (100g). For example, the vehicle may include a vehicle equipped with a wireless communication function, an autonomous vehicle, a vehicle capable of performing vehicle-to-vehicle communication, etc. Here, the vehicles (100b-1, 100b-2) may include unmanned aerial vehicles (UAVs) (e.g., drones). The XR devices (100c) include augmented reality (AR) / virtual reality (VR) / mixed reality (MR) devices, and may be implemented in the form of head-mounted devices (HMDs), head-up displays (HUDs) installed in vehicles, televisions, smartphones, computers, wearable devices, home appliances, digital signage, vehicles, robots, etc. The portable devices (100d) may include smartphones, smart pads, wearable devices (e.g., smartwatches, smart glasses), computers (e.g., laptops, etc.), etc. The home appliances (100e) may include TVs, refrigerators, washing machines, etc. The IoT devices (100f) may include sensors, smart meters, etc.For example, the base station (120) and the network (130) may also be implemented as wireless devices, and a specific wireless device (120a) may act as a base station / network node to other wireless devices.

[0084] Wireless devices (100a to 100f) can be connected to a network (130) via a base station (120). AI technology can be applied to the wireless devices (100a to 100f), and the wireless devices (100a to 100f) can be connected to an AI server (100g) via a network (130). The network (130) can be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR), or a 6G network. The wireless devices (100a to 100f) can communicate with each other via the base station (120) / network (130), but can also communicate directly (e.g., sidelink communication) without going through the base station (120) / network (130). For example, vehicles (100b-1, 100b-2) can communicate directly (e.g., V2V (vehicle to vehicle) / V2X (vehicle to everything) communication). Additionally, an IoT device (100f) (e.g., a sensor) can communicate directly with another IoT device (e.g., a sensor) or another wireless device (100a to 100f).

[0085] Wireless communication / connection (150a, 150b, 150c) can be established between wireless devices (100a to 100f) / base stations (120), and base stations (120) / base stations (120). Here, the wireless communication / connection can be established through various wireless access technologies such as uplink / downlink communication (150a), sidelink communication (150b) (or D2D communication), and base station-to-base station communication (150c) (e.g., relay, IAB (integrated access backhaul)). Through the wireless communication / connection (150a, 150b, 150c), the wireless device and base station / wireless device, and base stations and base stations can transmit / receive wireless signals to / from each other. For example, the wireless communication / connection (150a, 150b, 150c) can transmit / receive signals through various physical channels. To this end, based on various proposals of the present disclosure, at least some of various configuration information setting processes for transmitting / receiving wireless signals, various signal processing processes (e.g., channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), resource allocation processes, etc. may be performed.

[0086]

[0087] Devices applicable to the present disclosure

[0088] FIG. 2 illustrates an example of a wireless device applicable to the present disclosure.

[0089] Referring to FIG. 2, the wireless device (200) can transmit and receive wireless signals via 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 at least one memory (204), and may additionally include at least one transceiver (206) and / or at least one antenna (208).

[0090] 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 operational flowcharts disclosed in this document. For example, the processor (202) may process information in the memory (204) to generate first information / signal, and then transmit a wireless signal including the first information / signal via the transceiver (206). In addition, the processor (202) may receive a wireless signal including second information / signal via the transceiver (206), and then store information obtained from 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, the memory (204) may store software code including 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 operational flowcharts disclosed herein. Here, the processor (202) and the memory (204) may be part of a communication modem / circuit / chip designed to implement wireless communication technology. The transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals via at least one antenna (208). The transceiver (206) may include a transmitter and / or a receiver. The transceiver (206) may be used interchangeably with an RF (radio frequency) unit. In the present disclosure, a wireless device may also mean a communication modem / circuit / chip.

[0091] Hereinafter, the 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., a functional layer such as physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), radio resource control (RRC), and service data adaptation protocol (SDAP)). At least one processor (202) may generate at least one Protocol Data Unit (PDU) and / or at least one Service Data Unit (SDU) according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. At least one processor (202) may generate a message, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. At least one processor (202) can generate a signal (e.g., a baseband signal) including a PDU, an SDU, a message, control information, data or information according to the functions, procedures, proposals and / or methods disclosed in this document, and provide the signal to at least one transceiver (206). At least one processor (202) can receive a signal (e.g., a baseband signal) from at least one transceiver (206) and obtain the PDU, SDU, message, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed in this document.

[0092] At least one processor (202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. The 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 the at least one processor (202). The descriptions, functions, procedures, proposals, methods, and / or operation flowcharts 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. The descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document may be included in the at least one processor (202), or may be stored in at least one memory (204) and driven by the at least one processor (202). The descriptions, functions, procedures, suggestions, 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.

[0093] At least one memory (204) can be connected to at least one processor (202) and can store various forms of data, signals, messages, information, programs, codes, instructions and / or commands. The at least one memory (204) can be configured as a read only memory (ROM), a random access memory (RAM), an erasable programmable read only memory (EPROM), a flash memory, a hard drive, a register, a cache memory, a computer readable storage medium and / or a combination thereof. The at least one memory (204) can be located internally and / or externally to the at least one processor (202). In addition, the at least one memory (204) can be connected to the at least one processor (202) via various technologies such as a wired or wireless connection.

[0094] At least one transceiver (206) can transmit user data, control information, wireless signals / channels, etc., mentioned in the methods and / or flowcharts of this document to at least one other device. At least one transceiver (206) can receive user data, control information, wireless signals / channels, etc. mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts disclosed in this document from at least one other device. For example, at least one transceiver (206) can be connected to at least one processor (202) and can transmit and receive wireless signals. For example, at least one processor (202) can control at least one transceiver (206) to transmit user data, control information, or wireless signals to at least one other device. Furthermore, at least one processor (202) can control at least one transceiver (206) to receive user data, control information, or wireless signals from at least one other device. In addition, 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. mentioned in the descriptions, functions, procedures, proposals, methods and / or operation flowcharts 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).For this purpose, at least one transceiver (206) may include an (analog) oscillator and / or filter.

[0095] The components of the wireless device described with reference to FIG. 2 may be referred to by different terms in terms of functionality. For example, the processor (202) may be referred to as a control unit, the transceiver (206) as a communication unit, and the memory (204) as a storage unit. In some cases, the communication unit may be used to mean at least a portion of the processor (202) and the transceiver (206).

[0096] The structure of the wireless device described with reference to FIG. 2 can be understood as the structure of at least a portion of various devices. For example, the structure of the wireless device illustrated in FIG. 2 can be at least a portion of various devices described with reference to FIG. 1 (e.g., a robot (100a), a vehicle (100b-1, 100b-2), an XR device (100c), a portable device (100d), a home appliance (100e), an IoT device (100f), an AI device / server (100g)). Furthermore, according to various embodiments, in addition to the components illustrated in FIG. 2, the device may further include other components.

[0097] For example, the device may be a portable device such as a smartphone, a smart pad, a wearable device (e.g., a smart watch, smart glasses), or a portable computer (e.g., a 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., an audio input / output port, a video input / output port), and an input / output unit for inputting and outputting image information / signals, audio information / signals, data, and / or information input from a user.

[0098] For example, the device may be a mobile device such as a mobile robot, a vehicle, a train, an aerial vehicle (AV), a ship, etc. In this case, the device may further include at least one of a driving unit including at least one of an engine, a motor, a power train, wheels, brakes, and a steering unit of the device, a power supply unit including a wired / wireless charging circuit, a battery, etc. that supplies power, a sensor unit that senses status 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 obtains location information of the mobile device through a global positioning system (GPS) and various sensors.

[0099] For example, the device may be an XR device such as an HMD, a head-up display (HUD) installed in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance, a 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 obtains control information, data, etc. from the outside and outputs the generated XR object, and a sensor unit that senses status information, environmental information, and user information of the device or the surroundings of the device.

[0100] For example, the device may be a robot that can be classified into industrial, medical, household, military, etc. types 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 status information, environmental information, and user information of the device or its surroundings, and a driving unit that performs various physical actions, such as moving the robot joints.

[0101] For example, the device may be an AI device such as a TV, a projector, a smartphone, a PC, a laptop, a digital broadcasting terminal, a tablet PC, a wearable device, a set-top box (STB), a radio, a washing machine, a refrigerator, digital signage, a robot, a 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 status information, environmental information, and user information of the device or its surroundings, and a training unit that trains a model composed of an artificial neural network using learning data.

[0102] The structure of the wireless device illustrated in FIG. 2 may be understood as a part of a RAN node (e.g., a base station, DU, RU, RRH, etc.). That is, the device illustrated in FIG. 2 may be a RAN node. In this case, the device may further include a wired transceiver for front haul and / or back haul communications. However, if the front haul and / or back haul communications are based on wireless communications, at least one transceiver (206) illustrated in FIG. 2 may be used for front haul and / or back haul communications, and a wired transceiver may not be included.

[0103]

[0104] FIG. 3 illustrates a method for processing a transmission signal applicable to the present disclosure. For example, the transmission signal may be processed by a signal processing circuit. At this time, the signal processing circuit (300) may include scramblers (310), modulators (320), a layer mapper (330), a precoder (340), resource mappers (350), and signal generators (360). At this time, for example, the operation / function of FIG. 3 may be performed in the processor (202) and / or the transceiver (206) of FIG. 2. Furthermore, for example, the hardware elements of FIG. 3 may be implemented in the processor (202) and / or the transceiver (206) of FIG. 2. For example, blocks 310 to 360 may be implemented in the processor (202) of FIG. 2. Additionally, blocks 310 to 350 may be implemented in the processor (202) of FIG. 2, and block 360 may be implemented in the transceiver (206) of FIG. 2, and are not limited to the above-described embodiment.

[0105] The codeword can be converted into a wireless signal through the signal processing circuit (300) of FIG. 3. Here, the codeword is an encoded bit sequence of an information block. The information block may include a transport block (e.g., a UL-SCH transport block, a DL-SCH transport block). Here, the information block may include data related to AI (e.g., training data, AI model data, input data, output data, etc.), and the codeword may be an encoded bit sequence corresponding to the data related to AI. The wireless signal may be transmitted through various physical channels (e.g., a PUSCH, a PDSCH). Specifically, the codeword may be converted into a bit sequence scrambled by scramblers (310). The scramble sequence used for scrambling is generated based on an initialization value, and the initialization value may include ID information of the wireless device, etc. The scrambled bit sequence may be modulated into a modulation symbol sequence by modulators (320). Modulation schemes may include pi / 2-BPSK (pi / 2-binary phase shift keying), m-PSK (m-phase shift keying), m-QAM (m-quadrature amplitude modulation), etc.

[0106] A complex modulation symbol sequence can be mapped to at least one transport layer by a layer mapper (330). Here, a transport layer is a logical resource unit for mapping a signal or data transmitted through spatial resources to antenna ports, and one transport layer can correspond to one stream or one antenna port. Each of the complex modulation symbols included in the complex modulation symbol sequence is mapped to at least one transport layer, thereby determining which antenna port it will be transmitted through. The modulation symbols of each transport layer can be mapped to the corresponding antenna port(s) by a precoder (340). The output z of the precoder (340) can be obtained by multiplying the output y of the layer mapper (330) by a precoding matrix W of NХM. Here, N is the number of antenna ports, and M is the number of transport layers. Here, the precoder (340) may perform precoding after performing transform precoding (e.g., discrete Fourier transform (DFT) transform) on complex modulation symbols. Additionally, the precoder (340) may perform precoding without performing transform precoding.

[0107] Resource mappers (350) can map modulation symbols of each antenna port to time-frequency resources. The time-frequency resources may include a plurality of symbols (e.g., CP-OFDMA symbols, DFT-s-OFDMA symbols) in the time domain and a plurality of subcarriers in the frequency domain. Signal generators (360) generate wireless signals from the mapped modulation symbols, and the generated wireless signals can be transmitted to other devices through each antenna. To this end, each of the signal generators (360) may include an inverse fast Fourier transform (IFFT) module, a cyclic prefix (CP) inserter, a digital-to-analog converter (DAC), a frequency uplink converter, etc.

[0108] The signal processing process for a received signal in a wireless device may be configured in reverse order of the signal processing process (310 to 360) of FIG. 3. For example, a wireless device (e.g., 200 of FIG. 2) may receive a wireless signal from the outside through an antenna port / transceiver. The received wireless signal may be converted into a baseband signal through a signal restorer. For this purpose, the signal restorer may include a frequency downlink converter, an analog-to-digital converter (ADC), a CP remover, and a fast Fourier transform (FFT) module. Thereafter, the baseband signal may be restored to a codeword through a resource demapper process, a postcoding process, a demodulation process, and a descrambling process. The codeword may be restored to the original information block through decoding. Therefore, a signal processing circuit (not shown) for a received signal may include a signal restorer, a resource demapper, a postcoder, a demodulator, a descrambler, and a decoder.

[0109] The signal processing circuit (300) described with reference to FIG. 3 is exemplified as including a plurality of scramblers (310), modulators (320), a plurality of resource mappers (350), and a plurality of signal generators (360). However, at least one of the scramblers, modulators, resource mappers, and signal generators may be implemented as a single integrated structure. That is, the number of at least one of the scramblers, modulators, resource mappers, and signal generators may be smaller than the number of layers. Furthermore, at least one of the components exemplified in FIG. 3 may be omitted.

[0110]

[0111] Figure 4 illustrates a communication procedure between a terminal and a base station applicable to the present disclosure. Figure 4 illustrates operations of a terminal (410) and a base station (420) transmitting and / or receiving data and operations performed prior thereto.

[0112] Referring to FIG. 4, in step 401, the terminal (410) and the base station (420) perform synchronization. For example, the terminal (410) performs an initial cell search operation. Specifically, the terminal (410) can detect at least one synchronization signal transmitted from the base station (420) according to a predefined rule. Here, the synchronization signal can include multiple synchronization signals classified according to structure or purpose (e.g., primary synchronization signal, secondary synchronization signal). Through this, the terminal (410) can check the boundary of the frame, subframe, slot, and / or symbol of the base station (420) and obtain information about the base station (420) (e.g., cell identifier).

[0113] In step 403, the terminal (410) obtains system information transmitted from the base station (420). The system information is information related to the properties, characteristics, and / or capabilities of the base station (420) required to access the base station (420) and use the service, and may be classified by content (e.g., whether it is essential for access), transmission structure (e.g., channel used, whether provided on-demand), etc., and may be classified into, for example, a master information block (MIB) and a system information block (SIB). If necessary, the terminal (410) may transmit a signal requesting system information before receiving the system information. The system information may include information related to an AI function. For example, the system information may include at least one of information related to an AI model, information related to training, and information related to inference / prediction, as information required for operations performed based on AI. However, the request and provision of the system information may be performed after a random access procedure described below.

[0114] In step 405, the terminal (410) and the base station (420) perform a random access procedure. The terminal (410) may transmit and / or receive at least one message (e.g., a random access preamble, a random access response (RAR) message, etc.) for the random access procedure based on information related to the random access channel of the base station (420) obtained through system information (e.g., channel position, channel structure, supported preamble structure, etc.). For example, the terminal (410) may transmit a preamble (e.g., MSG1) through the random access channel, receive an RAR message (e.g., MSG2), transmit a message (e.g., MSG3) including information related to the terminal (410) (e.g., identification information) to the base station (420) using scheduling information included in the RAR message, and receive a message (e.g., MSG4) for contention resolution and / or connection establishment. As another example, MSG1 and MSG3 may be sent and received as one message, or MSG2 and MSG4 may be sent and received as one message.

[0115] In step 407, the terminal (410) and the base station (420) perform signaling of control information. Here, the control information may be defined in various layers, such as a layer that controls a connection (e.g., a radio resource control (RRC) layer), a layer that handles mapping between logical channels and transport 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 (410) and the base station (420) may perform at least one of signaling for establishing a connection, signaling for determining settings related to communication, and signaling for indicating allocated resources. In addition, the signaling of the control information may be performed to convey information related to an AI function. For example, the information related to an AI function is information necessary for an operation performed based on AI, and may include at least one of information related to an AI model, information related to training, and information related to inference / prediction. More specifically, information related to the AI ​​function signaled in step 407 may be combined and / or combined with information related to the AI ​​function signaled in step 403, and the two may be defined in a hierarchical, mutually complementary, or substitutive structure.

[0116] In step 409, the terminal (410) and the base station (420) transmit and / or receive data. In other words, the terminal (410) and the base station (420) can process, transmit, and / or receive data based on the signaling of the control information. For example, when transmitting data, the terminal (410) or the base station (420) can 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 (410) or the base station (420) can perform at least one of signal extraction from resources, waveform demodulation for each antenna, signal arrangement considering layer mapping, constellation demapping, descrambling, and channel decoding. Here, the transmitted data is data related to AI, and may include, for example, data for AI-based operations or data generated by AI-based operations.

[0117] Steps 401 to 409 illustrated with reference to FIG. 4 do not necessarily have to be performed in the order illustrated in FIG. 4, and the order of at least some of the steps may vary. Furthermore, at least some of steps 401 to 409 may be combined into a single step or omitted. That is, the steps illustrated in FIG. 4 may be performed in various modified forms.

[0118]

[0119] 6G communication systems and core implementation technologies of 6G systems

[0120] The 5G system defines various operating bands within FR1 (frequency range 1), which covers 410 MHz to 7125 MHz, and FR2 (frequency range 2), which covers 24,250 MHz to 71,000 MHz. Various frequencies are being discussed as operating bands for the subsequent 6G system, and the use of higher frequencies than 5G systems is also being considered for wider bandwidth and higher transmission speeds. One such band is the THz (terahertz) frequency band, which covers approximately 100 GHz to 10 THz. The THz frequency band is a band that has both the transparency of radio waves and the straightness of light waves, and communications using the THz frequency band are expected to play a transitional role from existing radio-centered communications to lightwave-based communications.

[0121] 6G systems utilizing the THz frequency band have the following goals: 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 devices, vi) ultra-reliable connectivity, and vii) connected intelligence with machine learning capabilities. The vision of the 6G system can be divided into four aspects: “intelligent connectivity,” “deep connectivity,” “holographic connectivity,” and “ubiquitous connectivity,” and the 6G system can be designed to satisfy the requirements as shown in [Table 1] below.

[0122] Per device peak data rate1 TbpsE2E latency1 msMaximum spectral efficiency100 bps / HzMobility supportup to 1000 km / hrSatellite integrationFullyAIFullyAutonomous vehicleFullyXRFullyHaptic CommunicationFully

[0123] At this time, the 6G system may have key factors such as enhanced mobile broadband (eMBB), ultra-reliable low latency communications (URLLC), massive machine type communications (mMTC), AI integrated communication, tactile internet, high throughput, high network capacity, high energy efficiency, low backhaul and access network congestion, and enhanced data security. FIG. 5 illustrates an example of a communication structure that can be provided in a 6G system applicable to the present disclosure. Referring to FIG. 5, the 6G system is expected to have simultaneous wireless communication connectivity that is 50 times higher than that of a 5G wireless communication system. URLLC, a key feature of 5G, is expected to become an even more crucial technology in 6G communications, offering end-to-end latency of less than 1 ms. Furthermore, 6G systems will boast significantly higher volumetric spectral efficiency than the commonly used area spectral efficiency. 6G systems can offer extremely long battery life and advanced battery technologies for energy harvesting, eliminating the need for separate charging for mobile devices in 6G systems. New network characteristics in 6G may include:

[0124] - Satellite integrated network: 6G is expected to integrate with satellites to provide a global mobile network. The integration of terrestrial, satellite, and airborne networks into a single wireless communications system is crucial for 6G.

[0125] Connected Intelligence: Unlike previous generations of wireless communication systems, 6G is revolutionary, upgrading the wireless evolution from "connected objects" to "connected intelligence." AI can be applied at every stage of the communication process (or at every signal processing step, as described below).

[0126] - Seamless integration of wireless information and energy transfer: 6G wireless networks will transfer power to charge the batteries of devices such as smartphones and sensors. Therefore, wireless information and energy transfer (WIET) will be integrated.

[0127] - Ubiquitous super 3D connectivity: Access to networks and core network functions of drones and very low Earth orbit satellites will create super 3D connectivity in 6G ubiquitous.

[0128] Some general requirements for the new network characteristics of 6G, such as the above, may be as follows:

[0129] - Small cell networks: The concept of small cell networks was introduced to improve received signal quality in cellular systems by increasing throughput, energy efficiency, and spectral efficiency. Consequently, small cell networks are essential for 5G and beyond-5G (5GB) communication systems. Accordingly, 6G communication systems also adopt the characteristics of small cell networks.

[0130] Ultra-dense heterogeneous networks: Ultra-dense heterogeneous networks will be another key feature of 6G communication systems. Multi-tier networks comprised of heterogeneous networks improve overall QoS and reduce costs.

[0131] High-capacity backhaul: Backhaul connections are characterized by high-capacity backhaul networks to support high-volume traffic. High-speed fiber optics and free-space optics (FSO) systems may be potential solutions to this problem.

[0132] - Radar technology integrated with mobile technology: High-precision localization (or location-based services) through communications is a key feature of 6G wireless communication systems. Therefore, radar systems will be integrated with 6G networks.

[0133] - Softwarization and virtualization: Softwarization and virtualization are two critical features that form the foundation of the design process for 5GB networks to ensure flexibility, reconfigurability, and programmability. Furthermore, billions of devices can be shared on a shared physical infrastructure.

[0134] To satisfy the above-mentioned characteristics, the core implementation technologies of the 6G system may include artificial intelligence (AI), THz (terahertz) communication, optical wireless technology, FSO backhaul network, massive MIMO technology, blockchain, 3D networking, quantum communication, unmanned aerial vehicles, cell-free communication, wireless information and energy transfer (WIET), integration of sensing and communication, integration of access backhaul networks, holographic beamforming, big data analysis, and large intelligent surface (LIS).

[0135] For example, THz communication can be utilized in 6G systems. THz communication is a communication that utilizes a spectrum in a frequency band between 0.3 THz and 3 THz with a corresponding wavelength in the range of 0.1 mm to 1 mm, as shown in FIG. 6. Referring to FIG. 6, the frequency band of THz waves is located in the middle region between the infrared band and the millimeter wave band, and therefore, THz waves can be understood as radio waves with the shortest wavelength and light waves with the longest wavelength. Therefore, THz waves share some of the characteristics of infrared and microwave waves, and specifically, they can simultaneously have the transparency of electromagnetic waves and the straightness of light waves.

[0136]

[0137] Figure 7 illustrates a transmitter structure applicable to the present disclosure.

[0138] Referring to Figure 7, in order to modulate data into an optical signal, an optical source of a laser can be passed through an optical wave guide to change the phase of the signal, etc. At this time, data is loaded by changing the electrical characteristics through a microwave contact, etc. Therefore, the optical modulator output is formed as a modulated waveform.

[0139] Data may be provided from a data signal generator. Here, the data may include various user data, configuration information, control information, etc. transmitted through a channel. Furthermore, the data may include data related to AI-based operations, such as information for configuring an AI model, input / output data for tasks of the AI ​​model, etc. To this end, components related to AI functions (e.g., an AI processing unit) may be included in the data signal generator or may be linked to the data signal generator.

[0140] An optical / electronic converter (O / E converter) can generate THz pulses by optical rectification using a nonlinear crystal, photoelectric conversion using a photoconductive antenna, or emission from a bunch of relativistic electrons. The THz pulse generated in the above manner can have a length in the range of femtoseconds to picoseconds. The optical / electronic converter (O / E converter) performs down conversion by utilizing the nonlinearity of the device.

[0141] Considering the THz spectrum usage, it is likely that multiple contiguous GHz bands will be used for THz systems, either fixed or for mobile services. For an outdoor scenario, the available bandwidth can be categorized based on an oxygen attenuation of 10^2 dB / km in the spectrum up to 1 THz. Accordingly, a framework in which the available bandwidth is divided into multiple band chunks can be considered. As an example of this framework, if the THz pulse length for a single carrier is set to 50 ps, ​​the bandwidth (BW) becomes approximately 20 GHz.

[0142] Effective down-conversion from the infrared band to the THz band depends on how to utilize the nonlinearity of the optical / electrical converter (O / E converter). In other words, to down-convert to the desired THz band, it is necessary to design an O / E converter with the most ideal non-linearity for transferring to the THz band. If an O / E converter that is not suitable for the target frequency band is used, errors in the amplitude and phase of the pulse are likely to occur.

[0143] A THz transmission and reception system can be implemented using a single optical-to-electrical converter in a single-carrier system. Depending on the channel environment, optical-to-electrical converters may be required as many as the number of carriers in a multi-carrier system. This phenomenon will be particularly noticeable in a multi-carrier system that utilizes multiple broadbands according to the aforementioned spectrum usage plan. In this regard, a frame structure for the multi-carrier system may be considered. A signal down-frequency converted based on an optical-to-electrical converter may be transmitted in a specific resource region (e.g., a specific frame). The frequency region of the specific resource region may include multiple chunks. Each chunk may be composed of at least one component carrier (CC).

[0144] 6G systems may introduce AI technology. Efficient resource management and optimization are required to maintain connectivity between various services and devices. AI technology may include technologies that perform data analysis, pattern recognition, and predictive modeling using AI / ML (artificial intelligence / machine learning) models. Here, an AI / ML model can be understood as a set of parameter values ​​and / or weight values ​​related to mathematical formulas or algorithms generated through learning to discover patterns in input data or make predictions. To create such an AI / ML model, an AI / ML model learning process is required, which builds an AI / ML model by learning the relationship between inputs and outputs in a data-driven manner. Various learning algorithms, such as supervised learning, unsupervised learning, and reinforcement learning, can be utilized as learning algorithms. To generate output, a user can input specific data into a trained AI / ML model, and the process of obtaining output data by inputting input data into an AI / ML model can be referred to as AI / ML "inference" or "prediction."

[0145] Network control parameters can be obtained as output through AI / ML inference using trained AI / ML models. Users can utilize the output parameter values ​​to improve network efficiency. For example, AI technology can be utilized in various fields, such as wireless network resource allocation, traffic management, fault prediction, and quality of service (QoS) management. In particular, machine learning can efficiently allocate resources even in dynamically changing network environments based on real-time data. Therefore, AI technology can be utilized to provide hyper-connectivity and ultra-low latency.

[0146] At this time, AI / ML inference can be performed based on a combination of various devices. For example, the UE and the network can jointly perform AI / ML inference, and such an AI / ML model can be referred to as a two-sided AI / ML model or a two-sided model. In this case, the UE can perform the first part of the inference first, and the base station can perform the remaining inference, or vice versa. Alternatively, inference can be performed entirely on the UE, and such an AI / ML model can be referred to as a UE-side AI / ML model or a UE-side model.

[0147] Additionally, life cycle management (LCM) can be performed for AI / ML models. Life cycle management can include model training, model deployment, model inference, model monitoring, and model updates. This may require support for data collection, model training, functional / model identification, model delivery / transfer, model inference operations, functional / model selection / activation / deactivation / fallback, functional / model monitoring, model updates, and UE capabilities.

[0148] For example, AI / ML technology can be operated based on a functional framework such as FIG. 8. FIG. 8 illustrates an example of a functional framework for application of AI / ML technology applicable to the present disclosure. First, a data collection function (810) performs data preparation on input data collected from objects (e.g., UE, RAN node, network node, etc.) to generate training data (801), monitoring data (803), and / or inference data (805) including processed input data. A model training function (820), which receives training data (801) from the data collection function (810), performs training on an AI / ML model using the training data (801) and provides a trained / updated model (813) to a model repository (840). The model repository (840) can store and retain the received trained / updated model (813).

[0149] A management function (830) may be used to control AI / ML model training. The management function (830) may control the operation of the AI / ML model or AI / ML functions, or supervise their performance. To this end, the management function (830) may receive monitoring data (830) from the data collection function (810) and inference output (809) from the inference function (840). The management function (830) manages the data received from the data collection function (810) and the inference function (840) so that the inference task can be performed efficiently. That is, the management function (830) may transmit performance feedback or a retraining request (807) to the model training function (820) to improve the inference task. Here, the performance feedback may be used to indicate a learning goal or as a reward for reinforcement learning. Additionally, the management function (830) can transmit management instructions (811) that instruct the inference function (840) to select AI / ML models or AL / ML-based functions to be used, activate / deactivate them, or switch to non-AI / ML operation.

[0150] The inference function (840) generates an inference output (809) by performing inference and / or prediction using the inference data (805) received by the data collection function (810). Here, the inference output (809) refers to the inference output of the AI / ML model used by the inference function (840), and the details of the inference output may vary depending on the use case. The AI / ML model used by the inference function (840) can be controlled by the management function (830). That is, the management function (830) can transmit a model transfer / forward request signal (815) to request a necessary AI / ML model to the model repository function (850), and the model repository function (850) can transmit the corresponding AI / ML model to the inference function (840) via a model transfer / forward signal (817). Therefore, the inference function (840) can perform inference using the AI / ML model (817) according to the received management instruction (811).

[0151] Additionally, the management function (830) may trigger or perform a designated task / action based on the inference output (809). Accordingly, the management function (830) may trigger a task / action for another entity (e.g., at least one UE, at least one RAN node, at least one network node, etc.) or for itself. Any one of the functions exemplified in FIG. 8 described above may be performed by two or more entities, including the RAN, the network node, the network operator's OAM, or the UE, in collaboration. This may be referred to as a split AI operation.

[0152] Not all of the functions (810 to 850) illustrated in FIG. 8 need to be used to utilize the AI / ML model, and the method of combining them is not limited to a specific method. Accordingly, the functions (810 to 850) may be operated in an integrated manner, or some functions may be omitted. Furthermore, the functions (810 to 850) illustrated in FIG. 8 are not necessarily limited to being implemented as separate devices or apparatuses. For example, some or all of the functions (810 to 850) may be included in the processor (202) of FIG. 2. Furthermore, the model storage function (850) may be included in the memory (204) of FIG. 2.

[0153]

[0154] FIG. 9 illustrates an example of a procedure for utilizing an AI model applicable to the present disclosure. FIG. 9 illustrates a case where a model training function (820) is included in a network node and a model inference function (840) is included in a RAN node. Referring to FIG. 9, in step 1, RAN node 1 and RAN node 2 transmit input data (e.g., training data) for training an AI model to the network node. Here, RAN node 1 and RAN node 2 may transmit data collected from the UE (e.g., measurements of the UE related to RSRP, RSRQ, SINR of the serving cell and neighboring cells, the UE's position, speed, etc.) together to the network node. In step 2, the network node trains the AI ​​model using the received training data. In step 3, the network node distributes / updates the AI ​​model to RAN node 1 and / or RAN node 2. RAN node 1 and / or RAN node 2 may also continue model training based on the received AI model. In this procedure, it is assumed that the AI ​​model is deployed / updated only to RAN node 1. In step 4, RAN node 1 receives input data (e.g., inference data) for AI model inference from UE and RAN node 2. In step 5, RAN node 1 performs AI model-based inference using the received inference data to generate output data (e.g., prediction or decision). In step 6, if applicable, RAN node 1 may transmit model performance feedback to network nodes. In step 7, RAN node 1, RAN node 2, and UE (or 'RAN node 1 and UE', or 'RAN node 1 and RAN node 2') perform actions based on the output data. For example, in case of load balancing operation, the UE may move from RAN node 1 to RAN node 2. In step 8, RAN node 1 and RAN node 2 transmit feedback information to network nodes.

[0155] Network nodes can manage AI models based on feedback information regarding the AI ​​model's inference results. For example, the network node can perform additional training on the AI ​​model or generate additional information about the AI ​​model (e.g., performance information, accuracy information, etc.). If additional training is performed on the AI ​​model, the network node can distribute the updated AI model to RAN node 1.

[0156] As described with reference to Figure 9, model training can be performed by network nodes, and inference using the model can be performed by RAN node 1. In other words, the model training and inference functions can be distributed. Typically, model training requires significant computational resources because it utilizes large amounts of data and complex algorithms for optimization. In contrast, inference, which uses a trained model to derive conclusions about new data, requires relatively fewer computational resources compared to model training. Therefore, using the procedure of Figure 9, model training can be performed through network nodes when the computational resources of the UE or RAN node are insufficient. Furthermore, security can be ensured for the AI ​​model because the AI ​​model is not disclosed to the UE.

[0157] FIG. 9 illustrates a case where a model training function (820) is included in a network node and a model inference function (840) is included in a RAN node, but the present disclosure is not limited thereto. For example, if the computational resources of the RAN node are sufficient, both the model training function (820) and the model inference function (840) may be included in RAN node 1. In this case, RAN node 1 receives training data for training an AI model from the UE and RAN node 2. RAN node 1 trains the AI ​​model using the received training data. Thereafter, RAN node 1 receives inference data for AI model inference from the UE and RAN node 2. RAN node 1 performs inference based on the AI ​​model using the received inference data to generate output data. Based on the output data, the UE, RAN node 1, and RAN node 2 may perform operations related to communication (e.g., handover, cell change). Thereafter, the UE and RAN node 2 may transmit feedback regarding the operations to RAN node 1. Therefore, RAN node 1 can learn the AI ​​model and update its own AI model using feedback information regarding the AI ​​model's inference results. According to the aforementioned method, signaling with the network is not required for AI model learning and inference, thereby reducing network load and delays until the AI ​​model is trained or inference results are received. Furthermore, since the UE performs inference using the AI ​​model, its personal information is not transmitted to network nodes, etc., thereby enhancing the security of personal information.

[0158] As another example, the model training function (820) may be included in the RAN node, and the model inference function (840) may be included in the UE. The RAN node receives training data for training an AI model from the UE, and trains the AI ​​model using the received training data. The RAN node distributes the trained AI model to the UE. The UE may perform inference based on the received AI model to generate output data. At this time, the data for inference may be received from the RAN node, or the UE may use data acquired on its own. The UE and the RAN node may perform communication-related operations based on the output data generated by inference. Thereafter, the UE may transmit feedback regarding the operation to the RAN node. Therefore, the RAN node may train the AI ​​model and distribute the updated AI model to the UE through feedback information regarding the inference result of the AI ​​model. According to the above-described method, the model training function (820) may be included in the RAN node, and the model inference function (840) may be included in the UE to perform inference, thereby reducing the load on the RAN node. Additionally, if the UE uses data acquired on its own to make inferences, even if the UE loses connection with the RAN node after receiving the AI ​​model, the UE can continue to infer the distributed AI model and perform operations based on the inference results.

[0159] According to the framework and procedures described above, an AI model can be trained and utilized in a wireless communication system. The model training function (820) and the model inference function (840) can be combined in various ways and are not necessarily limited to the case of FIG. 9. In the framework and procedures described above, various types of data, such as input data, training data, and inference data, are introduced, and the specific content of the data described above may vary depending on the task for which the AI ​​model is utilized. For example, information used in various embodiments of the present disclosure described below may be included in the data described above.

[0160] Figure 10 illustrates an AI technology-based communication procedure applicable to the present disclosure. The detailed procedures illustrated in Figure 10 can be combined with various embodiments of the present disclosure described below. For example, data generated according to various embodiments of the present disclosure can be used for operations (e.g., configuration, training, inference, and / or data transmission / reception) in at least one of the detailed procedures illustrated in Figure 10. As another example, the results of the inference illustrated in Figure 10 can be used to transmit and / or receive data according to various embodiments of the present disclosure.

[0161] Referring to FIG. 10, in step S1001, at least one of the UE (1010), the RAN node (1020), and the network node (1030) performs an initial access procedure. For example, in this step, at least one of an initial cell search operation, a system information acquisition operation, a random access operation, and a registration operation may be performed. In step S1003, at least one of the UE (1010), the RAN node (1020), and the network node (1030) performs a configuration procedure. Through the configuration procedure, parameters, resources, connections, and / or entities necessary for performing subsequent procedures in layers between the UE (1010) and the RAN node (1020) and / or in at least one layer between the UE (1010) and the network node (1030) may be determined and / or created. In this case, the configuration procedure may be performed based on information, status, and / or characteristics of an AI model used for subsequent training and inference.

[0162] In step S1005, at least one of the UE (1010), the RAN node (1020), and the network node (1030) performs a model training procedure. At least one of the UE (1010), the RAN node (1020), and the network node (1030) may collect training data and perform learning using the training data. For example, the model training procedure may be performed as described with reference to FIG. 9. If an offline-trained model is used, this step may be omitted.

[0163] In step S1007, at least one of the UE (1010), the RAN node (1020), and the network node (1030) performs a task using the trained model. That is, the task may be performed based on the results of inference and / or prediction using the trained model. For example, the task may be a procedure belonging to a communication protocol, and may be a preparatory operation for subsequent data transmission and / or reception, or may be related to data transmission and / or reception, or may be related to data processing (e.g., encoding, decoding, etc.).

[0164] In step S1009, at least one of the UE (1010), the RAN node (1020), and the network node (1030) transmits and / or receives data. At this time, the result of the task performed in step 1007 may be used. In some cases, the task performed in step 1007 may include transmitting and / or receiving data, in which case this step may be omitted as it is part of step 1007.

[0165] Specific embodiments of the present disclosure

[0166] Transmitting quantum states in quantum communications can present numerous challenges. For example, as transmission distance increases, photon loss occurs in the quantum channel, reducing transmission efficiency. Furthermore, interactions with the surrounding environment can lead to decoherence, altering the quantum state. Therefore, intermediate nodes may be required for long-distance quantum communication. Using repeaters as intermediate nodes presents significant technical challenges. Furthermore, noise and interference generated during long-distance transmission can alter the quantum state. Therefore, methods utilizing devices other than repeaters have been proposed. The present disclosure proposes a procedure for performing asynchronous, detector-independent, quantum secure direct communication (AMDI QSDC) using intermediate nodes in a communication system utilizing quantum entanglement. By using intermediate nodes, the distance at which messages can be transmitted using quantum signals can be increased. Furthermore, since synchronous detection is not required, the range of message transmission can be increased compared to asynchronous measurement device independent (AMDI) quantum secure direct communication using intermediate nodes. Below, the basic characteristics of quantum communication are described.

[0167] Classical computers have internal calculation units, and the basic calculation unit of a computer is a bit, which has two states: 0 and 1. Meanwhile, in quantum mechanics, a single quantum can be in a superposition of multiple states, and quantum computers utilizing this are being studied. The quantum bits used in quantum computers are called qubits (quantum bits) to distinguish them from the bits in classical computers. In other words, a single quantum can be in both a 0 state and a 1 state. However, when a quantum in a superposition state is measured, it collapses into one of the superposition states, determining the state as either 0 or 1.

[0168] To represent qubits in quantum systems, a method for representing superposed quantum states is needed. One way to represent quantum states is through Dirac notation, also known as bra-ket notation.

[0169] A ket can represent a quantum state Ψ, which can be expressed in the form |Ψ〉. A bra represents the complex conjugate transpose of a ket, which can be expressed in the form 〈φ|. Therefore, 〈φ| and |φ〉 form a complex conjugate transpose relationship.

[0170] The inner product between two states can be computed by combining bras and kets. For example, the inner product between two states |Ψ〉 and |φ〉 can be expressed in the form 〈Ψ|φ〉. In addition, all quantum states can be assumed to be normalized. That is, we can define a set of state functions that satisfy 〈Ψ|Ψ〉 = 1. This set is defined as the Hilbert space. In addition, two quantum states that produce a bra-ket result of 0 in the Hilbert space can be defined to be orthogonal. Therefore, if 〈Ψ|φ〉 = 0, the relationship between the |Ψ〉 state and the |φ〉 state is orthogonal to each other.

[0171] Entanglement

[0172] Entanglement is a very important property that differentiates quantum systems from classical information. Entanglement refers to a state in which the results of different observations are closely related to each other. The entanglement state of a quantum system acts more strongly than any correlation that exists in classical mechanics. Two qubits can be represented as a superposition of four fundamental quantum states in Hilbert space. Here, the four fundamental quantum states are { , , , } is included. The basic quantum state of two qubits can be expressed through tensor operations on the basic states of individual qubits. If the state of two qubits cannot be expressed as a tensor product of a single qubit, such a qubit state is called an entangled state. There are four cases, which are representative examples of qubits in an entangled state and are called EPR (Einstein-Podolsky-Rosen) states, and the four cases are as shown in [Mathematical Formula 1] below.

[0173]

[0174]

[0175]

[0176]

[0177] In [Equation 1] can be used when transmitting classical information 00, can be expressed as, can be used to transmit classical information 10, can be expressed as, can be used when transmitting classic information 01, can be expressed as, can be used to transmit classical information 11, can be expressed as . The matching relationship between quantum states and classical information can be defined differently from the above.

[0178] The above EPR state is also called the Bell state, and the measurement result of the preceding qubit always affects the measurement of the succeeding qubit. Furthermore, all four of the above pure states are maximally entangled states and form the vertical basis of the two-qubit Hilbert space.

[0179] For entangled qubits with M>2 qubits or more, the GHZ state is as follows [Mathematical Equation 2].

[0180]

[0181] In [Equation 2], stands for tensor product operator.

[0182] When M=2 The GHZ state is generally expressed for M = 3. Sometimes, the GHZ state can be expressed by extending it to a system corresponding to d-dimension rather than 2-dimension.

[0183] The decay of quantum information by measurement

[0184] Quantum information exists probabilistically, and quantum information collapses to a ground state at the moment of measurement and cannot be restored to the state before measurement. The quantum information after measurement by the measurement operator is a probability and It collapses into one of the states of the basis that constitutes information. The collapsed information does not have the information of 'a' or 'b' and cannot return to the state before measurement.

[0185] From the perspective of quantum error-correcting codes, applying quantum error-correcting codes in quantum information systems requires generating codewords, estimating errors in the channel, and restoring the information without measuring the information during the encoding and restoration process, or without measurements that would alter the information. Information communication can utilize the three properties of quantum information—superposition, entanglement, and the influence of observation—as shown in Figure 11.

[0186] Figure 11 illustrates three fundamental properties of quantum information that can be utilized for information communication applicable to the present disclosure. Superposition is a property in which quantum information exists probabilistically before being measured. The quantum information collapses to an instantaneous basis state due to the influence of observation at the moment of measurement and cannot be restored to the state before the measurement. Furthermore, due to entanglement, when a qubit in one system is measured, information about the qubit in another system can also be obtained. For example, after measurement, quantum information has a probability |a| 2 A basis state with probability |b| 2 It collapses into the B basis state. Therefore, the collapsed information only has information about A or B, and does not have the information of A and B superimposed, and cannot return to the state before measurement.

[0187] quantum teleportation (QT)

[0188] Quantum teleportation is a technology that transmits quantum information from a sender at a specific location to a receiver located a certain distance away. Unlike traditional teleportation, which involves transmitting actual carriers, quantum teleportation transmits quantum information while the carriers on both sides remain fixed. This quantum information transmission requires entangled quantum states, or Bell states. Bell states can be used to establish statistical correlations between distinct physical systems. Because any change experienced by one of the entangled particles causes the other particle to experience the same change, the two particles can be interpreted as acting as a single quantum state.

[0189] FIG. 12 illustrates an example of a quantum transmission protocol according to one embodiment of the present disclosure. Quantum transmission requires a classical channel capable of transmitting two classical bits, an entanglement state (e.g., Bell state) generation device, a quantum channel for moving two particles in an entangled state to transmitting and receiving devices located at different locations, a Bell state measurement device at a transmitting end, and a unitary computation device at a receiving end. For example, a classical channel may be a wireless channel in a wireless communication system, and bits transmitted through the wireless channel may be classical bits. As another example, a classical channel may be a wired channel in a wired communication system. However, in the following, the terms classical channel and classical bit are used to clarify the difference between a quantum channel and a conventional communication channel, but the present invention is not limited thereto. In other words, a classical channel may be any channel for transmitting data.

[0190] In addition, the following describes a method for performing two-way communication between a first device (1210) and a second device (1220), and the devices may not be limited to a specific form.

[0191] For example, the quantum information you want to transmit The quantum transmission protocol for can be expressed as follows.

[0192] - Entanglement generation: An entangled state of two qubits is created using a Bell state generator.

[0193] - Entanglement distribution: The generated entangled state qubits are moved through a quantum channel, with one qubit moving to the location of the first transmitter device (1210) and the other qubit moving to the location of the second receiver device (1220).

[0194] - Quantum pre-processing: The first device (1210) measures the Bell state for the quantum state |φ〉 to be transmitted and one qubit of the Bell state it has. Therefore, the first device (1210) can obtain a result corresponding to one of the Bell states. At this time, the qubit state that the second device (1220) has in response to the result of the Bell state measurement of the first device (1210) is as shown in [Table 2] below.

[0195] BSM Results of and Alice's QubitBob's Qubit

[0196] - Classical information transmission: The first device (1210) encodes the Bell state measurement result into two classical bits and transmits it to the second device (1220). - Quantum post-processing: The second device (1220) can obtain a quantum state identical to the quantum information |φ〉 that the first device (1210) wants to transmit by performing a unitary operation on the remaining qubit of the Bell state that it has through the two classical bits received from the first device (1210).

[0197] quantum direct communication (QDC)

[0198] Quantum direct communication (QKD) is a method for securely transmitting classical message information. It shares similarities with quantum key distribution (QKD), a technology used in 4G and 5G secure communication, but there are also differences. Quantum key distribution (QKD) utilizes the unclonable nature of quantum mechanics to securely transmit message information transmitted over classical channels, sharing symmetric secret key information between the sender and receiver. In contrast, quantum direct communication (QD) shares the classical message information to be transmitted directly over the quantum channel, rather than a secret key.

[0199] Among quantum direct communication technologies, quantum secure direct communication (QSDC) boasts the advantage of not generating information leaks related to transmitted information, ensuring high reliability. A two-step QSDC technique utilizing entangled light sources is currently being studied. This two-step QSDC can be implemented based on super-dense coding techniques.

[0200] Super dense coding technique is a technique that can safely transmit classical information using quantum communication. It is a technique that can stably transmit 2 bits of classical information using the four types of single entangled photons (hereinafter referred to as EPR-pairs) of [Mathematical Formula 3] below.

[0201]

[0202]

[0203]

[0204]

[0205] When using superdense coding, a transmitter can transmit two bits of classical information to a receiver using a single qubit through a quantum channel. First, two entangled qubits are created. The transmitter owns the first entangled qubit, and the receiver owns the second entangled qubit. There are four cases for the qubit that the transmitter wants to transmit: '00', '01', '10', and '11'. For each of the four cases above, the transmitter performs a qubit operation corresponding to each of the four cases on the entangled qubit it owns and then transmits it through the quantum channel. At this time, the qubit operation can be expressed in the form of I, Z, X, and iY. Each operation performed by the transmitter can change the entanglement state shared by the transmitter and receiver into a different basis form that is orthogonal to each other. Therefore, the receiver measures the qubit it owns and recovers the two bits of information transmitted by the transmitter.

[0206] FIG. 13 illustrates an example of a procedure for transmitting quantum information in a two-step quantum secure direct communication according to an embodiment of the present disclosure. In FIG. 13, SRs 1 to SR 4 are optical delay lines that serve as quantum memories. CEs (checking eavesdropping) 1 and CE 2 are devices that check for the presence of eavesdroppers. CM (coding message) is a device that encodes classical message information to be transmitted from a transmitter (1310) to a receiver (1320). An EPR source is a device that generates an entangled light source in an EPR state, and a bell state measurement device is a device that measures an entangled photon pair. Furthermore, in quantum communication, the transmitter (1310) may be referred to as the first device (1310) or Alice, and the receiver (1320) may be referred to as the second device (1320) or Bob, and the same notation may be used below.

[0207] In two-step quantum secure direct communication, unlike superdense coding, entangled photon pairs are not transmitted all at once, but are transmitted in two stages through an upper quantum channel and a lower quantum channel. To eavesdrop on the entangled light source, an eavesdropper must know information from both sides of the entangled photon pair to measure and decipher the transmitted information. To prevent eavesdropping, two-step quantum secure direct communication uses a method where one side of the entangled photon pair is transmitted first, and its security is verified against eavesdropping. Once security is guaranteed, the remaining part of the photon pair, which encodes the message information to be sent, is then transmitted.

[0208] The aforementioned QSDC protocol can directly transmit messages using quantum states. In quantum communication techniques, eavesdropping attacks are primarily conducted at the detector. To counter this, a detector-independent (measurement device independent, MDI) QSDC protocol has been developed.

[0209] For convenience of explanation, in the following, a device that sends data is referred to as a transmitting node, a device that receives data is referred to as a receiving node, and nodes other than the transmitting node and receiving node that participate in data communication are referred to as nodes. In quantum communication, the transmitting node may be referred to as Alice, the receiving node may be referred to as Bob, and the intermediate node may be referred to as Charlie. Furthermore, in the present disclosure, the disclosure of information by a specific node means that another node can obtain the information. The method of obtaining the information is not limited to a specific method. For example, if an intermediate node discloses information A, the intermediate node may directly transmit information A to the receiving node and the transmitting node. As another example, the intermediate node may transmit information A to the control node, and the control node may transmit information A to the transmitting node and the transmitting node. Information A does not necessarily have to be transmitted through a quantum channel and may be transmitted through a classical channel. In the following, the information disclosed means information that cannot be obtained by an eavesdropper without knowing the message the transmitting node is trying to send, and it is assumed that the information is transmitted through a classical channel rather than a quantum channel.

[0210] MDI (measurement device independent) QSDC protocol

[0211] First, let's explain the MDI QSDC protocol. Below: , , , refers to an EPR-pair consisting of two qubits as in [Mathematical Formula 1], , , means a single qubit.

[0212] The first step is to prepare the quantum sequence in an entangled state by the transmitting node and the receiving node. The transmitting node Generate EPR-pairs and divide the generated EPR-pairs into two single qubit sequences. Here, the EPR-pairs are It is assumed that the sequence stored by the transmitting node among the two single qubit sequences is , and the sequence transmitted by the transmitting node is expressed as Let's express it as . The transmitting node additionally Prepare a set of single qubits. The state of the single qubits can be determined as one of the states expressed in [Mathematical Formula 4] below.

[0213]

[0214] The transmitting node sequences the prepared single qubits. By inserting it at any position in the ordered sequence Creates.

[0215] The receiving node is A single-qubit sequence of dogs Create a sequence The state of the qubits included in can be determined as one of the states expressed in [Mathematical Formula 4] above. The generated EPR pairs can be used for information transmission, and single qubits can be used for security verification procedures.

[0216] The second step is where the intermediate node performs the measurement and publishes the measurement result. The transmitting node transmits the sequence to the intermediate node. The receiving node transmits a sequence to the intermediate node. is transmitted. The intermediate node performs Bell-basis measurements of the received sequences and publishes the measurement results. The single qubit composed of the EPR-pair of the transmitting node can collapse into one of the states as shown in [Mathematical Formula 4] above after the Bell-basis measurement. The transmitting node and the intermediate node cannot know which state the single qubit stored in the transmitting node collapses into. However, the receiving node can infer which state the single qubit stored in the transmitting node collapses into by the following method through the sequence initial state and the result published by the intermediate node.

[0217] For convenience of explanation, the initial state of the EPR-pair prepared by the transmitting node is , and the state of the qubit prepared by the receiving node is Assume that the intermediate node that receives qubits from the transmitting node and the receiving node is A Bell-basis measurement can be performed using a state as input. The intermediate nodes receive the Bell-basis measurement results. You can get one of the results 10, 11, 00, 01. The results of 10, 11, 00, 01 are respectively . The previous two results indicate that the qubit of the transmitting node is , which means that the qubits of the remaining transmitting nodes are derived from It can be determined that the receiving node is in a prepared state. It can be understood in the same way at the same time.

[0218] After the intermediate node's result is published, the receiving node and disclose the basis. The transmitting node stores a single qubit If you do this, you can get the same state as the receiving node. Or, even if the receiving node only discloses the basis, the sending node and the intermediate nodes can can be obtained. The storage qubit and operator of the transmitting node corresponding to the measurement result according to the qubit state of the receiving node is as shown in [Table 3] below.

[0219] Qubit state of the receiving node

[0220] In [Table 3] means the measurement information disclosed by the intermediate node and the column refers to the state of the qubit stored by the transmitting node, refers to an operator that makes the qubit stored by the transmitting node identical to the qubit state of the receiving node.

[0221] For example, an intermediate node If the receiving node discloses the qubit state it has prepared, Since we know that the qubits that the transmitting node is storing are , and the receiving node can know that its qubit state is It is the basis, go It is revealed that

[0222] The third step is to check whether there is any wiretapping. The transmitting node randomly inserted the The location and state of the single qubits of the dog are disclosed, and the receiving node discloses the state of the qubit at the corresponding location. Since the qubits are randomly selected by the transmitting and receiving nodes, if the same basis is selected, a measurement error rate that deviates from the baseline can be attributed to an eavesdropper. If a different basis is selected, all possible Bell states can be combined, making it impossible to determine the error rate using the qubits.

[0223] The fourth step is where the transmitting node transmits information. The receiving node transmits the base and Since the transmitting node has made the remaining Encoding operators on qubits can be applied. Encoding operator is as follows [Mathematical Formula 5].

[0224]

[0225] In [Equation 5], refers to an operator for completing quantum teleportation, stands for message encoding operation.

[0226] is an operator disclosed by the receiving node, and can play a role in making the qubit stored by the transmitting node into the same state as the qubit generated by the receiving node. is an encoding operator, the transmitting node transmits 0 information. To be used by the operator and to transmit 1 information Operators can be used. The sending node must ensure the integrity of the message. We also perform arbitrary encoding on the qubits of the dog.

[0227] The fifth step is when the sending node transmits the message. The sending node sends the message to the intermediate node after encoding is performed. A single qubit sequence is transmitted. The intermediate node performs unitary operations on the received qubit. Here, if the basis of the received qubit is If is set to , and the basis of the received qubit is If is set to . The intermediate node is then We perform measurements on a baseline and publish the results.

[0228] The receiving node can obtain the message and randomly encoded numbers that the transmitting node wants to send based on the published results.

[0229] The sixth step is to check whether there is any manipulation. The transmitting node Randomly encoded numbers are published on the qubits. If the error rate is lower than a threshold, it can indicate that the communication was conducted securely. Conversely, if the error rate is higher than the threshold, it can indicate that the communication was manipulated by an eavesdropper or intermediate node.

[0230] The aforementioned MDI QSDC protocol allows for relatively long-distance communication, but in situations where quantum repeaters are difficult to implement, a protocol capable of long-distance communication may be required. Therefore, the present disclosure proposes a method for performing an asynchronous measurement device independent quantum secure direct communication (AMDI QSDC) protocol. The AMDI QSDC protocol proposed in this disclosure can be used to perform long-distance communication using intermediate nodes rather than repeaters. The specific procedures of the AMDI QSDC protocol are described below.

[0231] FIG. 14 illustrates an example of a transmitting node transmitting a data signal using the AMDI QSDC protocol according to one embodiment of the present disclosure. Referring to FIG. 14 , the transmitting node can transmit the data signal to the receiving node using an intermediate node. In this case, the intermediate node includes two detectors.

[0232] Referring to FIG. 14, in step S1401, the transmitting node performs an initial connection procedure. The transmitting node may perform the initial connection procedure with the receiving node and / or the intermediate node, and establish a connection with the receiving node and / or the intermediate node. For convenience of explanation, the initial connection procedure between the transmitting node and the intermediate node is described, but the same method may be used for the initial connection procedure between the transmitting node and the receiving node. The transmitting node may receive system information from the intermediate node to perform the initial connection procedure. The system information may be transmitted through a master information block (MIB) and a system information block (SIB). The transmitting node may transmit a signal for initial connection (e.g., a random access preamble) to the base station based on the system information, and receive a response signal to the signal for initial connection from the base station.

[0233] In step S1403, the transmitting node transmits a signal for measurement to the intermediate node. The signal for measurement may include at least one qubit of a first single qubit sequence. The first single qubit sequence may be composed of qubits selected one from each pair among a plurality of qubit pairs in an entangled state. The remaining qubits not included in the first single qubit sequence are included in a second single qubit sequence. The transmitting node stores the second single qubit sequence for use in data transmission.

[0234] In step S1405, the transmitting node receives a measurement result regarding a signal for measurement from the intermediate node. The measurement result includes information regarding time intervals in which valid events occurred, and the time intervals can be indicated by a time index value. Here, a valid event means an event in which at least one of the qubits included in the signal for measurement of the transmitting node and the signal for measurement of the receiving node is detected by only one of the two detectors of the intermediate node. If less than one valid event occurs within a valid time interval, the remaining steps may not be performed and communication may be interrupted. The measurement result may be transmitted via a classical channel.

[0235] In step S1407, the transmitting node transmits data to the intermediate node based on the measurement result. The data signal is generated based on an encoded message based on a valid time interval pair among the time intervals in which valid events occurred. Here, the valid time interval pair is determined to include both a time interval in which the transmitting node transmitted a signal for measurement and a time interval in which the transmitting node did not transmit a signal for measurement. The data signal may be transmitted based on a pulse position when the Z basis is selected, and based on a phase difference when the Y basis is selected. A specific method for encoding data in a message and a method for generating a data signal will be described later.

[0236] When a data signal is transmitted to an intermediate node, the intermediate node discloses the reception result to the receiving node, and the receiving node can obtain the message that the transmitting node wants to send based on the disclosed result.

[0237] FIG. 15 illustrates an example of a receiving node receiving a data signal using the AMDI QSDC protocol according to one embodiment of the present disclosure. Referring to FIG. 15 , the receiving node can receive a data signal from a transmitting node using an intermediate node. In this case, the intermediate node includes two detectors.

[0238] Referring to Figure 15, in step S1501, the receiving node performs an initial connection procedure. The receiving node performs the initial connection procedure with the transmitting node and / or intermediate nodes, and can establish a connection with the transmitting node and / or intermediate nodes. Through this procedure, the receiving node can share information necessary for communication via a classical channel.

[0239] In step S1503, the receiving node transmits a signal for measurement to the intermediate node. The signal for measurement may include at least one qubit among the qubits of the single qubit sequence generated by the receiving node. Here, at least one qubit included in the signal for measurement may be determined independently from the signal for measurement of the transmitting node. Each of the qubits included in the single qubit sequence generated by the receiving node may be assigned to the same time interval as each of the qubits included in the single qubit sequence generated by the transmitting node.

[0240] In step S1505, the receiving node shares a valid time interval pair. The receiving node can determine a time interval pair that satisfies the condition that a qubit is transmitted in one time interval and a qubit is not transmitted in another time interval as a valid time interval pair. This condition must also be satisfied for the transmitting node. For example, if the transmitting node transmits a qubit and the receiving node does not transmit a qubit in the first time interval, and the transmitting node does not transmit a qubit and the receiving node transmits a qubit in the second time interval, the time interval pair including the first time interval and the second time interval can be determined as a valid time interval pair. In this case, the basis selected by the receiving node can be shared. The valid time interval pair and the basis selected by the receiving node can be shared via a classical channel.

[0241] In step S1507, the receiving node receives the detection result of the data signal from the intermediate node. The data signal is encoded by the transmitting node based on a valid time interval pair and transmitted to the intermediate node. The detection result of the data signal can be received via a classical channel.

[0242] At step S1509, the receiving node performs data decoding based on the detection result of the data signal. The receiving node can perform data decoding based on the detection result of the data signal and a basis selected by the receiving node.

[0243] FIG. 16 illustrates an example of an intermediate node supporting the AMDI QSDC protocol according to one embodiment of the present disclosure. Referring to FIG. 16 , the intermediate node can support a transmitting node transmitting a message to a receiving node. In this case, the intermediate node includes two detectors.

[0244] Referring to Figure 16, at step S1601, the intermediate node performs an initial connection procedure. The intermediate node performs the initial connection procedure with the transmitting node and / or receiving node, and can establish a connection with the transmitting node and / or receiving node. Through this procedure, the intermediate node can share information necessary for communication via a classical channel.

[0245] In step S1603, the intermediate node receives a first signal for measurement from the transmitting node and a second signal for measurement from the receiving node. The intermediate node can detect the first signal for measurement and the second signal for measurement using detectors. The intermediate node can obtain a time interval in which a valid event occurs through the detection result. Here, a valid event means an event in which at least one of the qubits included in the first signal for measurement and the second signal for measurement is detected by only one of the two detectors.

[0246] In step S1605, the intermediate node determines whether to interrupt communication. This decision may be based on the number of valid events occurring during the valid time interval. For example, if the rate of valid events occurring less than once during the valid time interval exceeds a threshold, quantum communication may be interrupted. Here, the valid time interval may refer to the entire time interval allocated to the signal for measurement.

[0247] In step S1607, the intermediate node shares the measurement results of the signal for measurement. The measurement results include information about time intervals in which valid events occurred, and the time intervals in which valid events occurred can be indicated by a time index value. Two time intervals among the time intervals in which valid events occurred are selected by the transmitting node and the receiving node. A pair of time intervals including the selected time intervals is used for transmitting the data signal. The measurement results and the selected time intervals can be shared via a classical channel.

[0248] At step S1609, the intermediate node receives a data signal from the transmitting node. The data signal may be transmitted based on pulse position or based on qubit phase difference.

[0249] In step S1611, the intermediate node transmits the detection result of the data signal to the receiving node. The detection result may include the pulse position of the data signal or information about the detector where the detection occurred. The detection result may be transmitted to the receiving node via a classical channel. The receiving node that receives the detection result can decode the data signal based on the basis selected by the receiving node.

[0250] FIG. 17 illustrates an example of a structure of nodes for transmitting or receiving signals for measurement according to one embodiment of the present disclosure. The transmitting node (1710), the receiving node (1720), and the intermediate node (1730) of FIGS. 14 to 16 can perform quantum communication based on the structure depicted in FIG. 17. Referring to FIG. 17, the transmitting node (1710) and the receiving node (1720) can transmit signals for measurement including photon qubits in quantum communication. For convenience of explanation in the present disclosure, it is assumed that quantum states are transmitted using photons.

[0251] The transmitting node (1710) may include an entanglement source (1711), an attenuator (ATT) (1712), and a quantum memory (1713). The entanglement source (1711) is a device that generates entangled photon pairs. The entangled photons generated by the entanglement source (1711) may exhibit strong correlations in polarization, phase, or time-bin states, and may be used in quantum communication protocols. The entanglement source (1711) may transmit all or part of the entangled photon pairs to the quantum memory (1713) or the attenuator (1712).

[0252] The quantum memory (1713) can store qubits received from the entanglement source (1711) for a certain period of time or permanently. The quantum memory (1713) can be implemented so that changes in the state of the qubits can be minimized to reduce qubit loss. The quantum memory (1713) can be implemented in various forms and is not limited to a specific form. For example, if the qubits are implemented using photons, the quantum memory (1713) can be implemented using a light bundle.

[0253] The attenuator (1712) can adjust the output of the photons received from the entanglement source (1711) to optimize the signal-to-noise ratio and reduce errors. The attenuator (1712) can change the intensity of the output signal to match the operating requirements of the single photon detector (SPD) and the beam splitter (BS) (1731) of the intermediate node (1730). The transmitting node (1710) can transmit a signal for measurement including at least one qubit selected from each pair of a plurality of qubit pairs to the intermediate node (1730) through the attenuators (1712, 1721).

[0254] The receiving node (1720) may include a laser (1721), an intensity modulator (IM) (1722), a phase modulator (PM) (1723), and an attenuator (1721). The laser (1721) may generate a single-photon qubit sequence. Since the receiving node (1720) does not necessarily need to generate a single-photon qubit sequence using an entangled photon pair, the laser (1721) may be used to generate a photon qubit. The intensity modulator (1722) may adjust the amplitude or intensity of the single qubit generated from the laser (1721), and the phase modulator (1723) may adjust the phase of the output signal of the intensity modulator (1722). A signal with adjusted amplitude and phase of the single-photon qubit generated from the laser (1721) may be transmitted to the intermediate node (1730) through the attenuator (1721). The receiving node (1720) can transmit a signal for measurement including at least one qubit of a single qubit sequence to the intermediate node (1730) through the attenuator (1721). Accordingly, the receiving node (1720) can generate a photonic qubit using a laser (1721) and transmit a single photon to the intermediate node (1730) through the intensity modulator (1722), the phase modulator (1723), and the attenuator (1721).

[0255] The intermediate node (1730) may include a single photon detector and beam splitters (1731). The beam splitter (1731) may split an incident optical signal into two or more paths and transmit the split signal to the single photon detectors (1732, 1733). The single photon detectors (1732, 1733) may detect individual photons from the optical signal received through the beam splitter (1731). The intermediate node (1730) may determine that a case in which a photon transmitted by a transmitting node (1710) and a receiving node (1720) is detected by a single single photon detector is a valid event and may disclose the time index of the detected photon to the receiving node (1720) and the transmitting node (1710).

[0256] After the time indices of valid events are disclosed, the sending node and the receiving node must determine a valid time interval pair with a correlation. A valid time interval pair with a correlation between the sending node and the receiving node must be valid for both the sending node and the receiving node. Therefore, a verification procedure can be performed between the sending node and the receiving node to determine the validity of the time interval pair. The method for determining the validity of the time interval pair is not limited to a specific method. For example, as described in FIGS. 14 to 16, the sending node may first receive the time index values ​​of valid events from an intermediate node and transmit the valid time interval pair to the receiving node. The receiving node may then transmit a message to the sending node confirming that the time interval pair received from the sending node is also a valid time interval pair for the sending node. As another example, the receiving node may first determine a valid time interval pair and transmit the time interval pair to the sending node, and the sending node may then confirm that the time interval pair is also a valid time interval pair for itself. As another example, both the transmitting node and the receiving node receive valid event time index values ​​from an intermediate node, each discloses a pair of time intervals that are valid for itself, and the same pair of time intervals can be used. Once a pair of time intervals that are valid for both the transmitting node and the receiving node are determined, data transmission based on photon pulse position or phase difference can be performed using the valid pair of time intervals.

[0257] Figure 18 illustrates an example of a procedure in which a transmitting node transmits data based on the pulse positions of photons, according to one embodiment of the present disclosure. In Figure 18, it is assumed that the transmitting node and the receiving node share a pair of valid time intervals. It is assumed that the receiving node has generated a photon sequence to be included in a signal for measurement using a Z basis, and has disclosed the basis selected by the receiving node to the transmitting node and intermediate nodes.

[0258] In step S1801, the transmitting node obtains a key value based on whether a photon has been transmitted. The key value may be determined based on the pattern in which photons are transmitted in a valid time interval pair. For example, if a photon is transmitted in the time interval corresponding to the first index and no photon is transmitted at the time corresponding to the second index, the key value may be set to 0. Conversely, if a photon is not transmitted in the time interval corresponding to the first index and a photon is transmitted at the time corresponding to the second index, the key value of the transmitting node may be set to 1. At this time, the receiving node can also obtain the key value of the transmitting node using the same method. Since the receiving node obtains the key value opposite to that of the transmitting node, it can share the key value with the transmitting node by applying a NOT operator to the obtained key value. Even if an eavesdropper knows a valid time interval pair, the eavesdropper cannot know the transmission pattern of the transmitting node, and therefore cannot know the key value. Therefore, the security of quantum communication can be maintained.

[0259] In step S1803, the transmitting node performs data encoding based on the determined key value. The transmitting node can convert the message to be transmitted into an encoded message through an exclusive OR operation with the determined key value.

[0260] In step S1805, the transmitting node generates a data signal based on the pulse position of the photon from the encoded data. The data signal can be generated according to the pulse position of the photon allocated to the time resource. For example, the time resource through which the photon can be transmitted can be divided into two time intervals, and if the pulse position of the photon exists in the first time interval, it can be set to mean '1', and if the pulse position of the photon exists in the second time interval, it can be set to mean '0'. In addition, '0' and '1' can be defined oppositely, and which setting to use can be preset between the transmitting node and the intermediate nodes.

[0261] In step S1807, the transmitting node transmits a data signal to the intermediate node. The intermediate node can obtain encoded data based on the pulse positions of the received data signal. However, since the intermediate node does not know the key value, it cannot obtain the message that the transmitting node actually intends to send. The intermediate node transmits the encoded data to the receiving node. The encoded data can be transmitted through a classical channel, and the receiving node can obtain the message that the transmitting node intends to send based on the key shared with the transmitting node.

[0262] Using Fig. 18, a message can be transmitted based on the pulse position. Below, a method of transmitting a message using the phase difference is described when the basis selected by the receiving node is the X basis. The intermediate node may include an interferometer that inputs two signals.

[0263] FIG. 19 illustrates an example of a structure of nodes for transmitting a data signal using a phase difference according to an embodiment of the present disclosure. Referring to FIG. 19, a transmitting node (1910) can transmit a signal encoded using a phase difference to an intermediate node (1930). Although not illustrated in FIG. 19, the transmitting node (1910) can include an entanglement source and an attenuator as in FIG. 17, and can transmit one of the qubit pairs generated from the entanglement source as a signal for measurement and store the other in a quantum memory (1911).

[0264] The transmitting node (1910) can encode the photon stored in the quantum memory (1911) using an encoding operator and then transmit it to the intermediate node (1930). Here, the encoding operator can change the phase of the stored photon. For example, if the message to be transmitted is '1', the phase of the stored photon can be changed by π without changing the phase of the stored photon. Accordingly, the transmitting node (1910) can transmit a signal modulated based on the phase to the intermediate node.

[0265] The intermediate node can measure the modulated signal received from the transmitting node. At this time, a single photon source (1934) can be used so that the detection result can vary depending on the phase. At this time, interference between the modulated signal transmitted by the transmitting node (1910) and the signal generated by the single photon source (1934) can occur in the beam splitter (1931). When interference between the two signals occurs, the single photon detector (1932 or 1933) that detects the signal can vary depending on the phase difference. Therefore, when the intermediate node discloses the detected single photon detector (1932 or 1933), the receiving node can derive the phase of the photon signal transmitted by the transmitting node (1910).

[0266] Figure 20 illustrates an example of an AMDI QSDC procedure according to one embodiment of the present disclosure. Using the procedure of Figure 20, a transmitting node can transmit data to a receiving node via an intermediate node. In Figure 20, it is assumed that the transmitting node, the receiving node, and the intermediate node can transmit and receive data to and from each other via a classical channel. In Figure 20, it is assumed that the intermediate node includes two detectors.

[0267] In step S2001, the transmitting node and the receiving node generate photons in a quantum state and transmit them to the intermediate node. The transmitting node and the receiving node decide whether to transmit the photons in a quantum state to the intermediate node. If the transmitting node decides to transmit the photons to the intermediate node, it generates an entangled photon pair as shown in [Mathematical Formula 6] below.

[0268]

[0269] The transmitting node transmits one of the generated entangled photon pairs to the intermediate node. The remaining one is stored. If the receiving node decides to transmit the quantum state, the photon prepared by the receiving node can be determined to be in one of the states shown in [Mathematical Equation 7] below.

[0270]

[0271] In [Equation 7] refers to the phase of the photon prepared by the receiving node.

[0272] The receiving node can transmit the prepared photon to the intermediate node. The transmitting and receiving nodes must store which basis was selected at the time of transmission. Here, the basis is Basal or A basis can be selected. At this time, the valid time interval can be defined. The valid time interval can be composed of multiple time sections. For example, the valid time interval can be composed of 8 time sections as shown in FIG. 21, and each time section can be indicated by a time index value. The transmitting node and the receiving node can determine whether to transmit a photon during each time section. The transmitting node and the receiving node can transmit the prepared photon in at least one time section among the time sections included in the valid time interval. It is not disclosed in which time section each node transmitted the photon.

[0273] In step S2003, the intermediate node determines whether communication is interrupted. Whether communication is interrupted can be determined based on the number of valid events. A valid event means that the photons transmitted by the transmitting node and the receiving node are detected by only one of the two detectors of the intermediate node. In this case, the valid time interval If the number of valid events during a time interval is less than one, then quantum communication is not performed during that time interval. That is, If a valid event occurs during the valid time interval, the event is removed. If the percentage of cases where the number of valid events during the period is less than or equal to one is higher than the threshold, the AMDI QSDC procedure may be aborted. Conversely, the valid time interval If there are more than two valid events during the valid time interval, the AMDI QSDC procedure can be continued. is a setting value that can vary depending on the laser used by the transmitting node and the receiving node, and two valid events within a valid time interval mean that there is a correlation.

[0274] In step S2005, the intermediate node shares the time intervals in which valid events occurred. The sharing of time intervals is not limited to a specific form. For example, the time intervals may be transmitted by transmitting all index values ​​of the time intervals in which valid events occurred. Alternatively, the transmission may be based on the index of the first time interval in which a valid event occurred and the index difference between the first time interval and the remaining time intervals. Furthermore, the intermediate node is not limited to sharing all time intervals in which valid events occurred. For example, the intermediate node may share only two time intervals in which valid events occurred with the transmitting node and the receiving node. At this time, the intermediate node may also share information about the detector in which detection occurred during each time interval.

[0275] In step S2007, the transmitting node and the receiving node determine a valid time interval pair based on the time intervals in which valid events occur. The transmitting node can disclose a valid time interval pair to itself among the valid time interval pairs received from the intermediate node. Here, a valid time interval pair means a time interval pair in which transmission was performed during one time interval and no transmission was performed during the other time interval. The receiving node selects a time interval pair that is also valid to itself among at least one time interval pair received from the transmitting node. If the receiving node selects the Z basis, step S2009 is performed, and if the receiving node selects the X basis, step S2015 is performed.

[0276] In step S2009, the transmitting node and the receiving node obtain a key value based on whether or not the photon was transmitted. The key value can be determined based on the order in which the transmissions were performed in a time-valid time pair. For example, if the transmitting node and the receiving node performed a transmission in the first time interval included in the time interval pair and did not perform a transmission in the second time interval, the transmitting node and the receiving node can determine '0' as the key value, and in the opposite case, the transmitting node and the receiving node can determine '1' as the key value. In this case, since only one detector is detected in the valid time interval, the transmitting node and the receiving node can be expected to have transmitted the photon in different time intervals. Therefore, the receiving node can obtain the same key value as the transmitting node by further performing a procedure of inverting the obtained key value.

[0277] In step S2011, the transmitting node performs data encoding based on the determined key value. The message to be transmitted can be converted into an encoded message through an exclusive OR operation with the determined key value. In other words, the key value obtained by the transmitting node and the message to be sent is When the encoded message is can be decided by

[0278] In step S2013, the transmitting node transmits a data signal modulated based on the pulse position of the photon. The encoded message can be modulated based on the pulse position of the photon and transmitted to the intermediate node. Specifically, the time interval during which the photon can be transmitted can be divided into a first time interval and a second time interval. The transmitting node can transmit the encoded message by including the pulse position of the photon in one of the first time interval and the second time interval.

[0279] When modulating the encoded message based on the pulse position at this time, the transmitting node can additionally perform modulation of the phase of the photon to be transmitted. The phase value that changes at this time can be set to any value. By modulating the phase, the eavesdropper can detect that the receiving node The security of communication can be improved because it becomes indistinguishable from the case where the basis is selected. An eavesdropper can check the pulse position of the photon. Even if the value can be obtained, the message information cannot be obtained because the key value shared by the transmitting node and the receiving node is not known. The data signal can be received by an intermediate node. The intermediate node can determine the photon position of the received data signal based on the You can obtain it, and the obtained can be transmitted to the receiving node. Afterwards, the receiving node performs an exclusive OR operation with the key value it has to receive the message. can be obtained.

[0280] In step S2015, the receiving node acquires the initial state of the transmitting node. The initial state of the transmitting node can be acquired based on detection information of the signal for measurement. The procedure for acquiring the initial state of the transmitting node based on detection information is described below.

[0281] All cases that can appear in a valid index pair (i, j) can be expressed as shown in [Table 4] below.

[0282] case 10vv020vv03πvv04πvv050vvπ60vvπ7πvvπ8πvvπ

[0283] In [Table 4], means the time index value, is index It refers to the phase of the photon transmitted by the receiving node within the corresponding time interval, can be selected arbitrarily. is index The entanglement state prepared by the transmitting node within the corresponding time interval It refers to the phase of a photon determined based on . means the detector, and v is indicated on the detector where the detection occurred among the two detectors. The two time indices When said, the photon state transmitted by the transmitting node and the receiving node can be expressed as in [Mathematical Formula 8] below.

[0284]

[0285] In [Equation 8], and are each index It means a state in which the transmitting node does not transmit photons and a state in which the receiving node does not transmit photons during a time interval, and are each index It means a state in which a transmitting node transmits a photon and a receiving node transmits a photon during a time interval, and are each index It refers to the initial photon state information of the transmitting node and the initial photon state of the receiving node during the time interval.

[0286] At this time, the initial photon state of the transmitting node can be inferred by the receiving node through the state of the receiving node based on the detection result, rather than being determined by the transmitting node. The photon state in which a valid detection event occurs in [Mathematical Equation 8] can be expressed as [Mathematical Equation 9] below.

[0287]

[0288] At this time, the state of passing through the beam splitter can be expressed as in [Mathematical Formula 10] below.

[0289]

[0290] In [Equation 10], is the index in the direction of the first detector It means an operator that generates a photon in the time interval corresponding to is the index in the direction of the second detector It refers to an operator that generates photons in the time interval corresponding to .

[0291] In [Equation 10] If , index and index If we display the cases detected in the corresponding time interval in order, or A photon is detected by the detector. That is, index and index A photon is detected by the same detector in the time interval corresponding to . If If or is detected by the detector. The receiving node can know the photon state it has prepared, so can be known. That is, the receiving node acquires the detection information based on the and information you know Using the phase information of the transmitting node, can be obtained.

[0292] The initial state of the sending node is index and index In the time interval corresponding to , if (00,00) or (11,11), The value of has a value of 0, if it is (00,11) or (11,00), The value of has the value of π. Therefore, the receiving node can obtain the initial state of the transmitting node based on the detection information.

[0293] In step S2017, the transmitting node transmits an encoded data signal based on the phase of the photon. The encoded data signal can be generated using the remaining qubits stored by the transmitting node. To this end, the transmitting node uses a message operator that can change the phase of the stored photon state. can be defined. For example, the phase that a message operator changes is the phase that a sent message changes. If , and the sending message is set to If can be set to .

[0294] Therefore, the phase and detection state of the photon for the transmitting node to transmit encoded data can be expressed as in [Mathematical Formula 11] below.

[0295]

[0296] In [Mathematical Formula 11], subscripts 1 and 2 represent detectors, respectively. means the mode connected to, represents the creation operator corresponding to each mode.

[0297] Therefore, the photon transmitted by the transmitting node is When the detector A photon is detected in When the detector is detected. Afterwards, the intermediate node discloses the detector where the detection event occurred. The receiving node receives the disclosed detector and the initial state of the transmitting node. Based on the value, send message can be obtained.

[0298] FIG. 22 illustrates an example of signaling for determining a valid index pair based on a signal for measurement according to one embodiment of the present disclosure. Referring to FIG. 22 , a transmitting node (2210) can select qubits corresponding to a valid index pair. In FIG. 22 , it is assumed that the quantum and classical channels required for signaling are available through an initial access procedure, etc.

[0299] Referring to FIG. 22, in steps S2201 and S2203, a transmitting node (2210) and a receiving node (2220) transmit signals for measurement to an intermediate node (2230). The transmitting node (2210) can generate pairs of entangled photons and transmit at least one photon selected from each pair to the intermediate node (2230). The receiving node (2220) can transmit at least one generated single photon to the intermediate node (2230).

[0300] For convenience of explanation, the effective time interval is as shown in Fig. 21. It is assumed that eight time intervals are included and an index is defined for each time interval. In addition, it is assumed that the transmitting node (2210) and the receiving node (2220) transmit photons for each interval corresponding to each time index as shown in [Table 5] below.

[0301] indexTransmitting nodeReceiving nodePhase 100002000π300-0400-π5-006-0π7--08--π

[0302] In [Table 5], 00 and 0 indicated in the transmitting node (2210) and receiving node (2220) mean that an entangled photon pair and a single photon were generated, respectively, and - indicates that no photon was generated. means the phase value of the photon transmitted by the receiving node (2220). That is, it means that during the time interval corresponding to index 1, both the transmitting node (2210) and the receiving node (2220) generated photons, and during the time interval corresponding to index 3, the transmitting node (2210) generated photons, but the receiving node (2220) did not generate photons.

[0303] For convenience of explanation, it is assumed that the transmitting node (2210) and the receiving node (2220) transmit all the patterns that can be transmitted by time interval as shown in [Table 5] above, but it is not limited to this. That is, whether the transmitting node (2210) and the receiving node (2220) transmit photons can be independently determined, and it is not necessarily limited to the valid time interval. Not all transmission patterns need to be included during the transmission.

[0304] At step S2205, the intermediate node (2230) determines whether communication is interrupted. The communication protocol may be interrupted if only one valid event occurs. For convenience of explanation, it is assumed that within the time intervals corresponding to indexes 1, 3, and 5, photons are detected by only one of the two detectors, resulting in three valid events. In the remaining time intervals, photons are either not detected or detected by both detectors.

[0305] In step S2207, the intermediate node (2230) transmits valid event index values ​​to the transmitting node (2210). All or some of the valid event index values ​​may be transmitted. For convenience of explanation, it is assumed that the intermediate node (2230) transmitted all of the valid event index values ​​1, 3, and 5 to the transmitting node (2210). The index values ​​may be transmitted via a classical channel.

[0306] In step S2209, the transmitting node (2210) transmits valid index pairs to the receiving node (2220). Here, a valid index pair means an index pair in which the transmitting node (2210) performed transmission during one time interval and did not perform transmission during another time interval during the time intervals included in the index pair.

[0307] Here, since the transmitting node (2210) performed transmission in both the time interval corresponding to index 1 and the time interval corresponding to index 3, (1, 3) is not a valid index pair. However, since the transmitting node (2210) performed transmission in the time interval corresponding to index 3 and did not perform transmission in the time interval corresponding to index 5, (3, 5) is a valid index pair. Similarly, (1, 5) is also a valid index pair. Therefore, the transmitting node (2210) can transmit at least one valid index pair of (1, 5) or (3, 5) to the receiving node (2220). The method by which the valid index pair is transmitted is not limited to a particular method. For example, a method may be used in which the transmitting node (2210) sequentially transmits (1, 5) and (3, 5), and the receiving node (2220) sequentially discloses a valid ordered pair to itself. A method may be used in which the transmitting node (2210) discloses all valid ordered pairs, and the receiving node (2220) discloses the ordered pairs that are valid for itself among the disclosed ordered pairs. For convenience of explanation, it is assumed below that both (1, 5) and (3, 5) have been transmitted.

[0308] In step S2211, the receiving node (2220) shares a valid index pair. To this end, the receiving node (2220) selects an index pair that is valid for itself from among the valid received index pairs. The receiving node (2220) did not perform transmission in the time interval corresponding to index 3, and performed transmission in the time interval corresponding to index 5. Therefore, (3, 5) is a valid index pair for the receiving node (2220). However, since the transmitting node (2210) performed transmission in the time interval corresponding to (1, 5), it is not a valid index pair for the receiving node (2220). Therefore, the receiving node (2220) shares the index pair (3, 5). The index pair (3, 5) is a valid index pair for both the transmitting node (2210) and the receiving node (2220), and can be used for message transmission. Afterwards, if the receiving node (2220) selects the Z basis, the data signal is transmitted based on the pulse position, and if the X basis is selected, the data signal is transmitted based on the phase difference.

[0309] Fig. 23 illustrates an example of signaling for transmitting data based on pulse positions according to one embodiment of the present disclosure. For convenience of explanation, Fig. 23 assumes that the procedure of Fig. 22 has been performed first. That is, it is assumed that the transmitting node (2310) and the receiving node (2320) have transmitted photons as shown in [Table 5] above, and that the index pair (3, 5) to be used for data communication is shared by each node. It is assumed that the receiving node (2320) has selected the Z basis when generating the photons.

[0310] In steps S2301 and S2303, the transmitting node (2310) and the receiving node (2320) determine key values. The transmitting node (2310) performed transmission in the time interval corresponding to index 3 and did not perform transmission in the time interval corresponding to index 5, so the transmitting node (2310) can obtain the key value '0'. In the same way, the receiving node (2320) can obtain the key value '1' of the receiving node (2320). The receiving node (2320) can obtain the same key value '0' as the transmitting node (2310) by inverting the obtained key value.

[0311] In step S2305, the transmitting node (2310) encodes the message to be transmitted. For convenience of explanation, it is assumed that the transmitting node (2310) transmits message '1'. The transmitting node (2310) performs message encoding through an exclusive OR operation using the message to be transmitted and its own key value '0' as input. Therefore, the transmitting node (2310) obtains the encoded message '1'.

[0312] In step S2307, the transmitting node (2310) performs pulse position-based modulation. The pulse position-based modulation can be performed by dividing the transmitting interval into a first time interval and a second time interval and utilizing the positions where the pulse positions of the photons exist. For example, if the encoded message is '1', the transmitting node (2310) can generate a data signal so that the pulse positions of the photons stored in the quantum memory exist within the first time interval. If the encoded message is '0', the transmitting node (2310) can generate a data signal so that the pulse positions of the photons stored in the quantum memory exist within the second time interval. The data signal can be generated using the remaining photons that are not included in the signal for measurement among the quantum pairs generated by the transmitting node (2310).

[0313] In step S2309, the transmitting node (2310) transmits the generated data signal to the intermediate node (2330). The data signal may be transmitted via a quantum channel. The data signal is transmitted in the first time interval to transmit the encoded message '1'. In addition, the data signal may be transmitted after performing phase modulation on the photons present in the first time interval to prevent eavesdroppers from obtaining information.

[0314] At step S2311, the intermediate node (2330) measures the data signal. The intermediate node (2330) can confirm that the received data signal exists in the first time interval and that the encoded message is a '1'. However, since the intermediate node (2330) does not know the key value, it cannot confirm the message that the transmitting node (2310) intends to send.

[0315] In step S2313, the intermediate node (2330) transmits the measurement result to the receiving node (2320). The measurement result may include information that the encoded message is '1'. At this time, the measurement result may be transmitted via a classical channel.

[0316] At step S2315, the receiving node (2320) obtains the message sent by the transmitting node (2310). The receiving node (2320) can perform message decoding through an exclusive OR operation using the encoded message '1' and its own key value '0' as input. As a result, the receiving node (2320) can obtain the message '1' sent by the transmitting node (2310).

[0317] Fig. 24 illustrates an example of signaling for transmitting data based on a phase difference according to an embodiment of the present disclosure. It is assumed that the procedure of Fig. 22 is performed first before the procedure of Fig. 24 is performed. That is, it is assumed that the transmitting node (2410) and the receiving node (2420) transmitted photons as shown in [Table 5], and the index pair (3, 5) to be used for data communication is shared by each node. In addition, it is assumed that the initial state is determined as case 3 of [Table 4] for convenience of explanation. That is, the phase difference of the photons corresponding to time index 3 and time index 5 stored by the transmitting node (2410) is , and the phase difference of the photon transmitted by the receiving node (2420) is It is assumed that. Since the transmitting node (2410) has prepared an entanglement order pair, it cannot know the exact phase difference of the photons it is storing, but since the receiving node (2420) has prepared a single photon, it can know the phase difference π of the photons it has prepared and transmitted. At this time, it is assumed that the receiving node (2420) has selected the X basis when generating the photon.

[0318] In step S2401, the transmitting node (2410) performs encoding based on the phase difference. The transmitting node (2410) can transmit a message using the remaining photons that are not included in the signal for measurement among the generated quantum pairs. The transmitting node (2410) can be a message operator. Encoding can be performed using . For example, if the message to be transmitted is '1', the transmitting node (2410) shifts the phase of the quantum to be transmitted by π, and if the message to be transmitted is '0', the message operator does not shift the phase of the quantum to be transmitted. can be defined. For convenience of explanation, it is assumed that the message to be transmitted is '1'. The transmitting node (2410) shifts the phase of the photon to be transmitted by π using the message operator. The transmitting node (2410) does not know its own initial phase difference, but the initial phase difference The phase difference is changed by moving That is, although the transmitting node (2410) does not know the exact values ​​of the initial phase difference and the changed phase difference, it can encode the phase of the photon it has stored to have a phase difference different from the initial phase difference. The transmitting node (2410) can generate an encoded signal including photons having the changed phase difference.

[0319] In step S2403, the receiving node (2420) obtains the initial state of the transmitting node (2410). To this end, the receiving node (2420) must obtain information about the detector in which the photon was detected in the index pair (3,5) to be used for data communication from the intermediate node (2430). Assuming case 3 in [Table 4], the receiving node (2420) can receive from the intermediate node (2430) that the photon was detected in the first detector in the time interval of index 3, and that the photon was detected in the second detector in the time interval of index 5. Referring to [Mathematical Formula 10], since the intermediate node (2430) was detected in a different detector in the index pair (3,5), the receiving node (2420) It can be seen that the phase difference of the photons it transmits is . Therefore, the receiving node (2420) knows the initial state phase difference of the transmitting node (2410). can be obtained.

[0320] In step S2405, the transmitting node (2410) transmits a data signal encoded based on a phase difference to the intermediate node (2430). The transmitting node (2410) can transmit the encoded signal prepared in step S2401 to the intermediate node (2430).

[0321] In step S2407, the intermediate node (2430) performs measurement of the photons received from the transmitting node (2410). At this time, the photons received from the transmitting node (2410) and the photons generated from the single photon source of the intermediate node (2430) interfere with each other in the beam splitter. Referring to [Mathematical Formula 11], The signal encoded in is a detector Photons are detected in .

[0322] At step S2409, the intermediate node (2430) transmits the measurement result to the receiving node (2420). The measurement result can be transmitted via a classical channel.

[0323] At step S2411, the receiving node (2420) obtains the message of the transmitting node (2410). The receiving node (2420) Since photons were detected in , It can be seen that the initial state phase difference of the photon generated by the transmitting node (2410) is Because I know, It can be seen that the receiving node (2420) can therefore obtain the message '1' from the transmitting node (2410).

[0324] Using the aforementioned method, even if an intermediate node or eavesdropper obtains the detection result, they cannot know what message the transmitting node is transmitting. Therefore, secure communication can be performed regardless of the detection result. In particular, since the detector is a device easily attacked in quantum communication, the method proposed in this disclosure that neutralizes attacks using the detector significantly enhances the security of quantum communication. Furthermore, because the method proposed in this disclosure does not require simultaneous detection events from two detectors, the effective transmission distance can be extended by utilizing the intermediate node. In particular, in environments where quantum repeaters cannot be used, the communication distance between the transmitting node and the receiving node can be increased, enabling long-distance communication.

[0325] Although it has been described that the transmitting node transmits at least one index pair that is valid for the transmitting node to the receiving node, and the receiving node uses an ordered pair that is valid for the receiving node among the at least one index pair received for quantum communication, it is not limited thereto. For example, the receiving node may first transmit a valid index pair to the transmitting node. As another example, the transmitting node and the receiving node may each transmit valid index pairs to each other, and communication may be performed using a matching index pair among the shared index pairs.

[0326] In this disclosure, the term "encoding" refers to altering a message to be transmitted so that it cannot be recognized by eavesdroppers or converting it into an optical signal, but is not limited to this term. Encoding may be replaced with technically equivalent or similar terms such as modulation, physical encoding, message encoding, optical encoding, optical modulation, and optical signal processing.

[0327] For convenience of explanation, the methods proposed in this disclosure are described as implementing quantum-state qubits using photons. However, this is not necessarily limited to implementing them using photons. For example, quantum-state qubits may be implemented using ion traps or superconductors.

[0328]

[0329] Below, examples of wireless device utilization to which various embodiments of the present disclosure are applied are described.

[0330] Figure 25 illustrates an example of a wireless device applicable to the present disclosure. The wireless device may be implemented in various forms depending on the use case / service (see Figure 1).

[0331] Referring to FIG. 25, the wireless device (200) corresponds to the wireless device (200) of FIG. 2 and may be composed of various elements, components, units / units, and / or modules. For example, the wireless device (200) may include a communication unit (210), a control unit (220), a memory unit (230), and additional elements (240). The communication unit may include a communication circuit (212) and a transceiver(s) (214). For example, the communication circuit (212) may include one or more processors (202) and / or one or more memories (204) of FIG. 2. For example, the transceiver(s) (214) may include one or more transceivers (206) and / or one or more antennas (208) of FIG. 2. The control unit (220) is electrically connected to the communication unit (210), the memory unit (230), and the additional elements (240) and controls the overall operations of the wireless device. For example, the control unit (220) can control the electrical / mechanical operations of the wireless device based on the program / code / command / information stored in the memory unit (230). In addition, the control unit (220) can transmit information stored in the memory unit (230) to an external device (e.g., another communication device) via a wireless / wired interface through the communication unit (210), or store information received from an external device (e.g., another communication device) via a wireless / wired interface in the memory unit (230).

[0332] The additional element (240) may be configured in various ways depending on the type of the wireless device. For example, the additional element (240) may include at least one of a power unit / battery, an input / output unit (I / O unit), a driving unit, and a computing unit. Although not limited thereto, the wireless device may be implemented in the form of a robot (Fig. 1, 100a), a vehicle (Fig. 1, 100b-1, 100b-2), an XR device (Fig. 1, 100c), a portable device (Fig. 1, 100d), a home appliance (Fig. 1, 100e), an IoT device (Fig. 1, 100f), a digital broadcasting terminal, a hologram device, a public safety device, an MTC device, a medical device, a fintech device (or a financial device), a security device, a climate / environmental device, an AI server / device (Fig. 1, 400), a base station (Fig. 1, 200), a network node, etc. Wireless devices may be mobile or stationary depending on the use / service.

[0333] In FIG. 25, various elements, components, units / parts, and / or modules within the wireless device (200) may be entirely interconnected via a wired interface, or at least some may be wirelessly connected via a communication unit (210). For example, within the wireless device (200), the control unit (220) and the communication unit (210) may be wired, and the control unit (220) and a first unit (e.g., 230, 240) may be wirelessly connected via the communication unit (210). In addition, each element, component, unit / part, and / or module within the wireless device (200) may further include one or more elements. For example, the control unit (220) may be composed of a set of one or more processors. For example, the control unit (220) may be composed of a set of a communication control processor, an application processor, an electronic control unit (ECU), a graphics processing processor, a memory control processor, etc. As another example, the memory unit (130) may be composed of RAM (Random Access Memory), DRAM (Dynamic RAM), ROM (Read Only Memory), flash memory, volatile memory, non-volatile memory, and / or a combination thereof.

[0334] Below, the implementation example of Fig. 25 is described in more detail with reference to the drawings.

[0335] Figure 26 illustrates examples of portable devices applicable to the present disclosure. Portable devices may include smartphones, smart pads, wearable devices (e.g., smartwatches, smartglasses), and portable computers (e.g., laptops, etc.). Portable devices may be referred to as Mobile Stations (MS), User Terminals (UT), Mobile Subscriber Stations (MSS), Subscriber Stations (SS), Advanced Mobile Stations (AMS), or Wireless Terminals (WT).

[0336] Referring to FIG. 26, the portable device (200) may include an antenna unit (208), a communication unit (210), a control unit (220), a memory unit (230), a power supply unit (240a), an interface unit (240b), and an input / output unit (240c). The antenna unit (208) may be configured as a part of the communication unit (210). Blocks 210 to 230 / 240a to 240c of FIG. 26 correspond to blocks 210 to 230 / 240 of FIG. 25, respectively.

[0337] The communication unit (210) can transmit and receive signals (e.g., data, control signals, etc.) with other wireless devices and base stations. The control unit (220) can control components of the mobile device (200) to perform various operations. The control unit (220) can include an AP (Application Processor). The memory unit (230) can store data / parameters / programs / codes / commands required for operating the mobile device (200). In addition, the memory unit (230) can store input / output data / information, etc. The power supply unit (240a) supplies power to the mobile device (200) and can include a wired / wireless charging circuit, a battery, etc. The interface unit (240b) can support connection between the mobile device (200) and other external devices. The interface unit (240b) can include various ports (e.g., audio input / output ports, video input / output ports) for connection with external devices. The input / output unit (240c) can input or output video information / signals, audio information / signals, data, and / or information input from a user. The input / output unit (240c) may include a camera, a microphone, a user input unit, a display unit (240d), a speaker, and / or a haptic module.

[0338] For example, in the case of data communication, the input / output unit (240c) obtains information / signals (e.g., touch, text, voice, image, video) input by the user, and the obtained information / signals can be stored in the memory unit (230). The communication unit (210) converts the information / signals stored in the memory into wireless signals, and can directly transmit the converted wireless signals to other wireless devices or to a base station. In addition, the communication unit (210) can receive wireless signals from other wireless devices or base stations, and then restore the received wireless signals to the original information / signals. The restored information / signals can be stored in the memory unit (230) and then output in various forms (e.g., text, voice, image, video, haptic) through the input / output unit (240c).

[0339] Figure 27 illustrates examples of vehicles or autonomous vehicles applicable to the present disclosure. The vehicles or autonomous vehicles may be implemented as mobile robots, cars, trains, manned or unmanned aerial vehicles (AVs), ships, etc.

[0340] Referring to FIG. 27, a vehicle or autonomous vehicle (200-1) may include an antenna unit (208-1), a communication unit (210-1), a control unit (220-1), a driving unit (240a-1), a power supply unit (240b-1), a sensor unit (240c-1), and an autonomous driving unit (240d-1). The antenna unit (208-1) may be configured as a part of the communication unit (210-1). Blocks 210-1 / 230-1 / 240a-1 to 240d-1 of FIG. 27 correspond to blocks 210 / 230 / 240 of FIG. 25, respectively.

[0341] The communication unit (210-1) can transmit and receive signals (e.g., data, control signals, etc.) with external devices such as other vehicles, base stations (e.g., base stations, roadside base stations (ROS), etc.), and servers. The control unit (220-1) can control elements of the vehicle or autonomous vehicle (200-1) to perform various operations. The control unit (220-1) may include an ECU (Electronic Control Unit). The drive unit (240a-1) can drive the vehicle or autonomous vehicle (200-1) on the ground. The drive unit (240a-1) may include an engine, a motor, a power train, wheels, brakes, a steering device, etc. The power supply unit (240b-1) supplies power to the vehicle or autonomous vehicle (200-1) and may include a wired / wireless charging circuit, a battery, etc. The sensor unit (240c-1) can obtain vehicle status, surrounding environment information, user information, etc. The sensor unit (240c-1) may include an IMU (inertial measurement unit) sensor, a collision sensor, a wheel sensor, a speed sensor, an incline sensor, a weight detection sensor, a heading sensor, a position module, a vehicle forward / backward sensor, a battery sensor, a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, a humidity sensor, an ultrasonic sensor, an illuminance sensor, a pedal position sensor, etc. The autonomous driving unit (240d-1) may implement a technology for maintaining a driving lane, a technology for automatically controlling speed such as adaptive cruise control, a technology for automatically driving along a set path, a technology for automatically setting a path and driving when a destination is set, etc.

[0342] For example, the communication unit (210-1) can receive map data, traffic information data, etc. from an external server. The autonomous driving unit (240d-1) can generate an autonomous driving route and driving plan based on the acquired data. The control unit (220-1) can control the drive unit (240a-1) so that the vehicle or autonomous vehicle (200-1) moves along the autonomous driving route according to the driving plan (e.g., speed / direction control). During autonomous driving, the communication unit (210-1) can irregularly / periodically acquire the latest traffic information data from an external server and can acquire surrounding traffic information data from surrounding vehicles. In addition, during autonomous driving, the sensor unit (240c-1) can acquire vehicle status and surrounding environment information. The autonomous driving unit (240d-1) can update the autonomous driving route and driving plan based on newly acquired data / information. The communication unit (210-1) can transmit information regarding the vehicle location, autonomous driving route, driving plan, etc. to an external server. The external server can predict traffic information data in advance using AI technology, etc. based on information collected from the vehicle or autonomous vehicles, and provide the predicted traffic information data to the vehicle or autonomous vehicles. If the device (220-2) is an autonomous vehicle, it can perform the same procedure as the vehicle or autonomous vehicle (200-1). In addition, if the device (220-2) is a base station or a roadside base station, the device (220-2) can transmit data, control signals, etc. to the vehicle or autonomous vehicle (200-1) through the communication unit (210-2).

[0343] Figure 28 illustrates an example of a vehicle applicable to the present disclosure. The vehicle may also be implemented as a means of transportation, a train, an aircraft, a ship, etc. Referring to Figure 28, the vehicle (200) may include a communication unit (210), a control unit (220), a memory unit (230), an input / output unit (240a), and a position measurement unit (240b). Here, blocks 210 to 230 / 240a to 240b correspond to blocks 210 to 230 / 240 of Figure 25, respectively.

[0344] The communication unit (210) can transmit and receive signals (e.g., data, control signals, etc.) with other vehicles or external devices such as base stations. The control unit (220) can control components of the vehicle (200) to perform various operations. The memory unit (230) can store data / parameters / programs / codes / commands that support various functions of the vehicle (100). The input / output unit (240a) can output AR / VR objects based on information in the memory unit (230). The input / output unit (240a) can include a HUD. The position measurement unit (240b) can obtain position information of the vehicle (200). The position information can include absolute position information of the vehicle (200), position information within a driving line, acceleration information, position information with respect to surrounding vehicles, etc. The position measurement unit (240b) can include GPS and various sensors.

[0345] For example, the communication unit (210) of the vehicle (200) can receive map information, traffic information, etc. from an external server and store them in the memory unit (230). The location measurement unit (240b) can obtain vehicle location information through GPS and various sensors and store the information in the memory unit (230). The control unit (220) can create a virtual object based on the map information, traffic information, and vehicle location information, and the input / output unit (240a) can display the created virtual object on the vehicle window (240a-1, 240a-2). In addition, the control unit (220) can determine whether the vehicle (200) is being driven normally within the driving line based on the vehicle location information. If the vehicle (200) abnormally deviates from the driving line, the control unit (220) can display a warning on the vehicle window through the input / output unit (240a). Additionally, the control unit (220) can broadcast a warning message regarding driving abnormalities to surrounding vehicles through the communication unit (210). Depending on the situation, the control unit (220) can transmit vehicle location information and information regarding driving / vehicle abnormalities to relevant authorities through the communication unit (210).

[0346] Figure 29 illustrates examples of XR devices applicable to the present disclosure. The XR devices may be implemented as HMDs, head-up displays (HUDs) installed in vehicles, televisions, smartphones, computers, wearable devices, home appliances, digital signage, vehicles, robots, and the like.

[0347] Referring to FIG. 29, the XR device (200a) may include a communication unit (210), a control unit (220), a memory unit (230), an input / output unit (240a), a sensor unit (240b), and a power supply unit (240c). Here, blocks 210 to 230 / 240a to 240c of FIG. 29 correspond to blocks 210 to 230 / 240 of FIG. 25, respectively.

[0348] The communication unit (210) can transmit and receive signals (e.g., media data, control signals, etc.) with external devices such as other wireless devices, portable devices, or media servers. The media data can include videos, images, sounds, etc. The control unit (220) can control components of the XR device (200a) to perform various operations. For example, the control unit (220) can be configured to control and / or perform procedures such as video / image acquisition, (video / image) encoding, metadata generation and processing, etc. The memory unit (230) can store data / parameters / programs / codes / commands required for driving the XR device (200a) / generating XR objects. The input / output unit (240a) can obtain control information, data, etc. from the outside, and output the generated XR object. The input / output unit (240a) can include a camera, a microphone, a user input unit, a display unit, a speaker, and / or a haptic module. The sensor unit (240b) can obtain the XR device status, surrounding environment information, user information, etc. The sensor unit (240b) may include a proximity sensor, an illuminance sensor, an acceleration sensor, a magnetic sensor, a gyro sensor, an inertial sensor, an RGB sensor, an IR sensor, a fingerprint recognition sensor, an ultrasonic sensor, a light sensor, a microphone, and / or a radar. The power supply unit (240c) supplies power to the XR device (200a) and may include a wired / wireless charging circuit, a battery, etc.

[0349] For example, the memory unit (230) of the XR device (200a) may include information (e.g., data, etc.) required for creating an XR object (e.g., AR / VR / MR object). The input / output unit (240a) may obtain a command to operate the XR device (200a) from the user, and the control unit (220) may operate the XR device (200a) according to the user's operating command. For example, when the user attempts to watch a movie, news, etc. through the XR device (200a), the control unit (220) may transmit content request information to another device (e.g., a mobile device (200b)) or a media server through the communication unit (230). The communication unit (230) may download / stream content such as movies and news from another device (e.g., a mobile device (200b)) or a media server to the memory unit (230). The control unit (220) controls and / or performs procedures such as video / image acquisition, (video / image) encoding, and metadata generation / processing for content, and can generate / output an XR object based on information about surrounding space or real objects acquired through the input / output unit (240a) / sensor unit (240b).

[0350] In addition, the XR device (200a) is wirelessly connected to the mobile device (200b) through the communication unit (210), and the operation of the XR device (200a) can be controlled by the mobile device (200b). For example, the mobile device (200b) can act as a controller for the XR device (200a). To this end, the XR device (200a) can obtain 3D location information of the mobile device (200b), and then generate and output an XR object corresponding to the mobile device (200b).

[0351] Figure 30 illustrates examples of robots applicable to the present disclosure. Robots can be classified into industrial, medical, household, and military types, depending on their intended use or field.

[0352] Referring to FIG. 30, the robot (200) may include a communication unit (210), a control unit (220), a memory unit (230), an input / output unit (240a), a sensor unit (240b), and a driving unit (240c). Here, blocks 210 to 230 / 240a to 240c of FIG. 30 correspond to blocks 210 to 230 / 240 of FIG. 25, respectively.

[0353] The communication unit (210) can transmit and receive signals (e.g., driving information, control signals, etc.) with external devices such as other wireless devices, other robots, or control servers. The control unit (220) can control components of the robot (200) to perform various operations. The memory unit (230) can store data / parameters / programs / codes / commands that support various functions of the robot (200). The input / output unit (240a) can obtain information from the outside of the robot (200) and output information to the outside of the robot (200). The input / output unit (240a) can include a camera, a microphone, a user input unit, a display unit, a speaker, and / or a haptic module. The sensor unit (240b) can obtain internal information of the robot (200), surrounding environment information, user information, etc. The sensor unit (240b) may include a proximity sensor, an illuminance sensor, an acceleration sensor, a magnetic sensor, a gyro sensor, an inertial sensor, an IR sensor, a fingerprint recognition sensor, an ultrasonic sensor, a light sensor, a microphone, a radar, etc. The driving unit (240c) may perform various physical operations, such as moving the robot joints. In addition, the driving unit (240c) may enable the robot (200) to drive on the ground or fly in the air. The driving unit (240c) may include an actuator, a motor, wheels, brakes, propellers, etc.

[0354] Figure 31 illustrates an example of an AI device applicable to the present disclosure.

[0355] AI devices can be implemented as fixed or mobile devices, such as TVs, projectors, smartphones, PCs, laptops, digital broadcasting terminals, tablet PCs, wearable devices, set-top boxes (STBs), radios, washing machines, refrigerators, digital signage, robots, and vehicles.

[0356] Referring to FIG. 31, the AI ​​device (200) may include a communication unit (210), a control unit (220), a memory unit (230), an input / output unit (240a / 240b), a learning processor unit (240c), and a sensor unit (240d). Blocks 210 to 230 / 240a to 240d of FIG. 31 correspond to blocks 210 to 230 / 140 of FIG. 25, respectively.

[0357] The communication unit (210) can transmit and receive wired and wireless signals (e.g., sensor information, user input, learning models, control signals, etc.) with external devices such as other AI devices (e.g., 100a to 100f, 120 of FIG. 1) or AI servers (e.g., 100g of FIG. 1) using wired and wireless communication technology. To this end, the communication unit (210) can transmit information within the memory unit (230) to the external device or transfer a signal received from the external device to the memory unit (230).

[0358] The control unit (220) may determine at least one executable operation of the AI ​​device (200) based on information determined or generated using a data analysis algorithm or a machine learning algorithm. In addition, the control unit (220) may control components of the AI ​​device (200) to perform the determined operation. For example, the control unit (220) may request, search, receive, or utilize data from the learning processor unit (240c) or the memory unit (230), and may control components of the AI ​​device (200) to perform at least one executable operation, a predicted operation, or an operation determined to be desirable. In addition, the control unit (220) may collect history information including the operation contents of the AI ​​device (200) or user feedback on the operation, and store the collected history information in the memory unit (230) or the learning processor unit (240c), or transmit the collected history information to an external device such as an AI server (FIG. 1, 100g). The collected history information may be used to update a learning model.

[0359] The memory unit (230) can store data that supports various functions of the AI ​​device (200). For example, the memory unit (230) can store data obtained from the input unit (240a), data obtained from the communication unit (210), output data of the learning processor unit (240c), and data obtained from the sensing unit (140). In addition, the memory unit (230) can store control information and / or software codes necessary for the operation / execution of the control unit (220).

[0360] The input unit (240a) can obtain various types of data from the outside of the AI ​​device (200). For example, the input unit (220) can obtain learning data for model learning, input data to which the learning model will be applied, etc. The input unit (240a) may include a camera, a microphone, and / or a user input unit. The output unit (240b) may generate output related to vision, hearing, or touch. The output unit (240b) may include a display unit, a speaker, and / or a haptic module, etc. The sensing unit (140d) can obtain at least one of internal information of the AI ​​device (200), information about the surrounding environment of the AI ​​device (200), and user information using various sensors. The sensing unit (140d) may include a proximity sensor, an illuminance sensor, an acceleration sensor, a magnetic sensor, a gyro sensor, an inertial sensor, an RGB sensor, an IR sensor, a fingerprint recognition sensor, an ultrasonic sensor, a light sensor, a microphone, and / or a radar, etc.

[0361] The learning processor unit (240c) can train a model composed of an artificial neural network using learning data. The learning processor unit (240c) can perform AI processing together with the learning processor unit of the AI ​​server (Fig. 1, 100g). The learning processor unit (240c) can process information received from an external device via the communication unit (210) and / or information stored in the memory unit (230). In addition, the output value of the learning processor unit (240c) can be transmitted to an external device via the communication unit (210) and / or stored in the memory unit (230).

[0362] Figure 32 illustrates an example of a quantum communication device applicable to the present disclosure. The quantum communication device can be applied to various devices and can be operated in combination (or merged) with other non-quantum communication wired and / or wireless communication devices. Information in quantum communication can be a concept encompassing both bit information, the basic unit of classical information, and qubit information, the basic unit of quantum information.

[0363] The channel encoder (250) can encode the classical bits to be transmitted into coded bits. The channel encoder (250) can improve the reliability of the classical bits.

[0364] A quantum encoder (260) converts the encoded bits into a qubit basis (or computation basis). Here, the qubit basis is logical information about a quantum state and can be formed based on a physical quantum basis. For example, as a quantum basis at the transmitter and receiver, horizontal polarization and vertical polarization can be agreed to correspond to the qubit basis |0〉 and |1〉, respectively.

[0365] Classical information bits 0 or 1 can be converted into qubit basis |0〉 or |1〉 through a channel encoder (250) and a quantum encoder (260). The qubit basis generated at the transmitter can be transmitted to the receiver through a quantum channel.

[0366] The quantum decoder (270) at the receiving end can perform measurements based on a pre-arranged quantum basis and decode the qubit basis transmitted to the receiving end into coded bits. If multiple qubit basis determines the qubit state, a qubit coded deterministically or probabilistically can be obtained depending on the measured qubit basis.

[0367] The channel decoder (280) decodes the coded bits back into classical bits and can obtain the information bits sent by the transmitter.

[0368] The procedures related to the channel encoder (250) and channel decoder (280) indicated by dotted lines in FIG. 32 may be omitted. If the channel encoder (250) and channel decoder (280) are omitted, the qubit state can be transmitted from the quantum process of the transmitter to the receiver via a quantum channel. The received qubit state can be used by the quantum processor for various purposes. For example, to transmit the qubit state generated in the quantum processor, a quantum direct communication method in which the qubit state is converted into a photon and transmitted may be used, or a method in which quantum teleportation is performed based on an entanglement source shared by the transmitter and receiver in advance may be used. Here, quantum direct communication refers to a communication method in which classical message information to be transmitted is safely shared directly through a quantum channel, and quantum teleportation refers to a communication method in which quantum information itself is shared through a quantum entanglement channel.

[0369] The proposed methods described above can be implemented independently, but they can also be implemented as a combination (or merge) of some of the proposed methods. Rules can be defined so that the base station notifies the terminal of the applicability of the proposed methods (or information about the rules of the proposed methods) through a predefined signal (e.g., a physical layer signal or a higher layer signal).

[0370] The present disclosure may be embodied in other specific forms without departing from the technical ideas and essential features described herein. Therefore, the above detailed description should not be construed as limiting in all respects but rather as illustrative. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present disclosure are intended to be included within the scope of the present disclosure. Furthermore, claims that are not explicitly cited in the claims may be combined to form an embodiment or incorporated into a new claim through a post-filing amendment.

[0371] The embodiments described herein may be applied to various wireless access systems. Examples of such wireless access systems include the 3rd Generation Partnership Project (3GPP) or 3GPP2 systems.

[0372] The embodiments described herein can be applied not only to the various wireless access systems described above, but also to all technical fields utilizing these various wireless access systems. Furthermore, the proposed method can be applied to mmWave and THz communication systems utilizing ultra-high frequency bands.

[0373] Additionally, the embodiments can be applied to various applications such as autonomous vehicles and drones.

Claims

1. In a method performed by a first device in a communication system, Step of obtaining system information; A step of performing an initial connection procedure based on the above system information; A step of transmitting a first signal for measurement to a second device; A step of receiving information related to the measurement result from the second device; A step of generating a data signal in which data encoding is performed based on information related to the above measurement results; and Including a step of transmitting the above data signal to the second device, Information related to the measurement result includes information related to time intervals in which at least one of the qubits included in the first signal for the measurement and the second signal for the measurement transmitted by the third device was detected only by one of the two detectors of the second device, A method in which the above data encoding is performed based on information related to the above time intervals.

2. In paragraph 1, A method in which a first signal for the above measurement is generated based on a first single qubit sequence including a first qubit and a second qubit selected from each pair among a plurality of qubit pairs in an entangled state.

3. In paragraph 2, The time intervals detected by only one detector include a first time interval assigned to the first qubit and a second time interval assigned to the second qubit, A method wherein the first signal comprises a first time interval including the first qubit and a second empty time interval.

4. In paragraph 3, A method in which the data signal is transmitted through a quantum channel using at least one of a third qubit entangled with the first qubit or a fourth qubit entangled with the second qubit.

5. In paragraph 4, The above data encoding is performed based on the basis of the second signal for the measurement, The above data encoding is performed based on the pulse position when the basis of the second signal for the measurement is the first basis, A method in which the above data encoding is performed based on a phase difference when the basis of the second signal for the above measurement is a second basis.

6. In paragraph 5, The above data encoding is performed using a key value when the data encoding is performed based on the pulse position, A method in which the above key value is determined based on a comparison result between an index value of the first time interval and an index value of the second time interval.

7. In paragraph 6, A method further comprising the step of changing the phase of the data signal.

8. In paragraph 7, The pulse position of the data signal is measured by the second device, The pulse position of the above data signal is transmitted to the third device, A method in which the key value is shared by the first device and the third device based on an index value of the first time interval and an index value of the second time interval.

9. In paragraph 5, A method in which the above data encoding is performed by shifting the initial phase difference between the third qubit and the fourth qubit by a phase corresponding to the message to be transmitted, when the above data encoding is performed based on a phase difference.

10. In paragraph 9, A method in which the data signal is detected by one of the two detectors through interference with a single photon source of the second device.

11. In paragraph 3, A method in which the second signal for the above measurement does not include the fifth qubit within the first time interval and includes the sixth qubit within the second time interval.

12. In paragraph 3, A step of transmitting an index pair including an index value of the first time interval and an index value of the second time interval to the third device; and A method further comprising the step of receiving valid information of the index pair from the third device.

13. In paragraph 3, A method further comprising the step of stopping quantum communication when the rate at which only one of the two detectors is detected during the entire time interval allocated to the first signal is greater than a threshold value.

14. In a method performed by a second device in a communication system, Step of obtaining system information; A step of performing an initial connection procedure based on the above system information; A step of receiving a first signal for measurement from a first device; A step of receiving a second signal for measurement from a third device; A step of determining whether communication is interrupted based on a first signal for the measurement and a second signal for the measurement; A step of transmitting information related to the measurement result to the first device; A step of receiving a data signal on which data encoding is performed based on information related to the measurement result from the first device; and Including a step of transmitting the detection result of the data signal to the third device, Information related to the measurement result includes information related to time intervals in which at least one of the qubits included in the first signal for the measurement and the second signal for the measurement was detected only by one of the two detectors of the second device, A method in which the above data encoding is performed based on information related to the above time intervals.

15. In claim 14, A method further comprising the step of transmitting detector information corresponding to information related to time intervals included in information related to the measurement result to the third device.

16. In a method performed by a third device in a communication system, Step of obtaining system information; A step of performing an initial connection procedure based on the above system information; A step of transmitting a second signal for measurement to a second device; A step of receiving a detection result of a data signal transmitted by the first device from the second device; and Including a step of performing data decoding based on the detection result of the above data signal, A method wherein the decoding is performed based on information related to time intervals in which at least one of the qubits included in the first signal for measurement transmitted by the first device and the second signal for measurement is detected only by one of the two detectors of the second device.

17. In paragraph 16, Further comprising the step of generating a single qubit sequence including a first qubit and a second qubit, The time intervals detected by only one detector include a first time interval assigned to the first qubit and a second time interval assigned to the second qubit, A method comprising: said second signal comprising said first time interval including said first qubit and said second time interval being empty.

18. In paragraph 17, The detection result of the above data signal includes the pulse position of the above data signal, Decoding of the above data signal is performed using a key value based on the pulse position, A method in which the above key value is determined based on a comparison result between an index value of the first time interval and an index value of the second time interval.

19. In paragraph 17, A step of receiving first detector information about a detector that detected a qubit in the first time interval and second detector information about a detector that detected a qubit in the second time interval from the second device; A step of determining an initial phase difference between qubits generated by the first device based on the first detector information and the second detector information; and Further comprising a step of determining a phase difference between qubits included in the data signal based on the detection result, A method in which the above data decoding is performed using the initial phase difference and the phase difference between qubits included in the data signal.

20. In paragraph 17, A step of receiving an index pair including an index value of the first time interval and an index value of the second time interval from the first device; and A method further comprising the step of transmitting valid information of the index pair to the first device.

21. In paragraph 16, A step of selecting a basis of the qubits included in the second signal; and A method further comprising the step of transmitting the selected base to the first device.

22. In the first device of the communication system, Transmitter and receiver; and comprising a processor coupled to the above transceiver, The above processor, Obtain system information, Obtain system information, Perform the initial connection procedure based on the above system information, Transmit a first signal for measurement to a second device, Receive information related to the measurement results from the second device, Generate a data signal on which data encoding is performed based on information related to the above measurement results, configured to transmit the above data signal to the second device, Information related to the measurement result includes information related to time intervals in which at least one of the qubits included in the first signal for the measurement and the second signal for the measurement transmitted by the third device was detected only by one of the two detectors of the second device, The above data encoding is performed by a first device based on information related to the time intervals.

23. In the second device of the communication system, Transmitter and receiver; and A processor connected to the above transmitter and receiver is included, The above processor, Obtain system information, Perform the initial connection procedure based on the above system information, Receive a first signal for measurement from a first device, Receive a second signal for measurement from a third device, Determine whether communication is interrupted based on the first signal for the above measurement and the second signal for the above measurement, Transmit information related to the measurement result to the first device, Receive a data signal on which data encoding is performed based on information related to the measurement result from the first device, configured to transmit the detection result of the data signal to the third device; Information related to the measurement result includes information related to time intervals in which at least one of the qubits included in the first signal for the measurement and the second signal for the measurement was detected only by one of the two detectors of the second device, A second device wherein the above data encoding is performed based on information related to the above time intervals.

24. In a third device in a communication system, Transmitter and receiver; and A processor connected to the above transmitter and receiver is included, The above processor, Obtain system information, Perform the initial connection procedure based on the above system information, Transmit a second signal for measurement to the second device, Receive the detection result of the data signal transmitted by the first device from the second device, Configured to perform data decoding based on the detection result of the above data signal, A third device wherein the decoding is performed based on information related to time intervals in which at least one of the qubits included in the first signal for measurement transmitted by the first device and the second signal for measurement was detected only by one of the two detectors of the second device.

25. In the first communication device, At least one processor; At least one computer memory connected to said at least one processor and storing instructions that direct operations when executed by said at least one processor, The above actions are, Step of obtaining system information; A step of performing an initial connection procedure based on the above system information; A step of transmitting a first signal for measurement to a second communication device; A step of receiving information related to the measurement result from the second communication device; A step of generating a data signal in which data encoding is performed based on information related to the above measurement results; and Including a step of transmitting a data signal to the second communication device, Information related to the measurement result includes information related to time intervals in which at least one of the qubits included in the first signal for the measurement and the second signal for the measurement transmitted by the third communication device was detected only by one of the two detectors of the second communication device, A first communication device wherein the above data encoding is performed based on information related to the above time intervals.

26. In a non-transitory computer-readable medium storing at least one instruction, comprising at least one instruction executable by the processor, At least one of the above commands causes the first device to: Obtain system information, Perform the initial connection procedure based on the above system information, Transmit a first signal for measurement to the second device. Receive information related to the measurement results from the second device, Generate a data signal on which data encoding is performed based on information related to the above measurement results, configured to transmit a data signal to the second device, Information related to the measurement result includes information related to time intervals in which at least one of the qubits included in the first signal for the measurement and the second signal for the measurement transmitted by the third device was detected only by one of the two detectors of the second device, A computer-readable medium in which the above data encoding is performed based on information related to the above time intervals.

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