Abstract: The present specification provides a method, performed by an apparatus, for transmitting at least one beam in a wireless communication system, the method comprising transmitting the at least one beam to another apparatus and receiving information about a result of measuring the at least one beam from the other apparatus, wherein the at least one beam is a beam generated on the basis of a signal synthesized from a laser signal being incident on a meta surface from a power controller, the laser signal consists of a plurality of frequency components, the synthesized signal is a signal in which power amplification is applied to each of the plurality of frequency components, and the power amplification is applied on the basis of the intensity regarding each of the plurality of frequency components.

Abstract: Provided are a method and a device used in an optical wireless communication (OWC) system. A receiver comprises an optical amplifier and detector that receives an optical signal including a target signal and/or daylight noise as an input to output baseband electrical signals for digital signal processing. The optical amplifier and detector comprises: (1) an optical amplifier that amplifies the optical signal; (2) an optical diplexer that filters the amplified optical signal into an in-band wavelength band and an out-of-band wavelength band, respectively; (3) an optical attenuator that receives the target signal present in the in-band wavelength band as an input and outputs an attenuated target signal; (4) a first photodetector that converts the attenuated target signal into a first baseband electrical signal; (5) an electric filter; and (6) a second photodetector that converts the daylight noise into a second baseband electrical signal.

Abstract: The present specification provides a method and a device, the method, performed by a device, for transmitting a first pulse train in a quantum communication system being characterized by: receiving a random access (RA) preamble from another device; transmitting an RA response (RAR) to the other device as a response to the RA preamble; performing a radio resource control (RRC) connection process with the other device; receiving data from the other device; and decoding the data on the basis of key information, wherein a first pulse train is generated in a laser diode of the device, and the key information is determined on the basis that the first pulse train passes through both a first path and a second path and is then transmitted from the device to the other device via a quantum channel.

Abstract: Disclosed are a multi-layer transmission and reception method in a communication system based on 1-bit quantization in a wireless communication system, and an apparatus for supporting same. Particularly, a method by which a first device transmits and receives a signal in a wireless communication system comprises the steps of: receiving a reference signal (RS) from a second device; generating a demodulation reference vector on the basis of the RS; and receiving a data signal from the second device by using the demodulation reference vector, wherein the RS can be generated differently according to the modulation of the data signal.

Abstract: Provided is a method and device for correcting an error in a communication system, the method including: transmitting, to another device, data encrypted based on key information. The key information is obtained by: incident a detection pulse on a variable Faraday rotating mirror and a reference pulse on a first mirror, respectively, wherein the detection pulse and the reference pulse are pulses branched from a test pulse; generating a first current in a balanced photodetector (BPD) based on a first component obtained as the detection pulse is reflected from the variable Faraday rotating mirror and a second component obtained as the reference pulse is reflected from the first mirror; converting the first current into a second current; incident the second current on the variable Faraday rotating mirror; and correcting the error in the variable Faraday rotating mirror based on the incident second current.

Abstract: Disclosed is a method by which a terminal controls the calculations of a deep neural network in a wireless communication system. A method according to one embodiment of the present disclosure receives a downlink from a base station of a wireless communication system by using a multi input multi output (MIMO) operation, pre-processes the downlink on the basis of a result of calculations of a deep neural network in a terminal, acquires the number of a plurality of transmission antennas connected to the terminal, acquires the number of a plurality of reception antennas connected to the terminal, and forms a plurality of overlapping neural networks overlapping in the deep neural network, on the basis of a preset number of reference antennas, the number of transmission antennas, and the number of reception antennas.

Abstract: Provided is an operation method of a first node in a communication system, according to various embodiments of the present disclosure, the method comprising the steps of: receiving one or more synchronization signals from a second node; receiving system information from the second node; identifying, for a bit flip channel, a bit correlation of a first number of n first qubits constituting an entanglement state between the first node and the second node; generating, on the basis of the bit correlation, a second number of n?1 auxiliary qubits; after an interaction with respect to the bit flip channel occurs, determining, on the basis of the second number of n?1 auxiliary qubits, whether a bit flip error has occurred with respect the entanglement state; and, if the bit flip error is determined to have occurred, carrying out error correction by means of a bit flip operation for the first qubits.

Abstract: The present disclosure is an embodiment of a method for operating a terminal, and the method for operating a terminal in a wireless communication system includes requesting, by the terminal, reference signal (RS) group-related configuration information to a base station, receiving RS group-related configuration information from the base station, learning a first parameter related to a meta-learning learning model based on the RS group-related configuration information, and receiving, by the terminal, a RS from the base station or transmitting a RS to the base station based on the first parameter. The RS group-related configuration information includes pattern information, an identifier and a weight value of at least one of a demodulation-reference signal (DM-RS), a phase-tracking reference signal (PTRS), a channel status information-reference signal (CSI-RS), a positioning reference signal (PRS), a synchronization signal block (SSB), a sounding reference signal (SRS), and a meta-learning RS.

Abstract: The present specification provides a method, performed by a device, for transmitting information about a pencil beam timing offset in a wireless optical communication system, in which a reference synchronization time is obtained, wherein the reference synchronization time is obtained on the basis of a cell-reference synchronization signal (C-RSS) received from another device, a peak energy time is obtained, the pencil beam timing offset is obtained on the basis of the reference synchronization time and the peak energy time, and information about the pencil beam timing offset is transmitted to the other device.

Abstract: The present disclosure relates to a quantum communication system, and specifically to a method and a device for the method, wherein the method comprises the steps of: acquiring configuration information about a quantum signal used for quantum communication; receiving, through a quantum channel, a first block sequence which includes a plurality of first single photons that correspond to the quantum signal, and generating a plurality of second single photons on the basis of the configuration information; inputting, to a beam splitter (BS), the first and second single photons which correspond to each other; and determining whether there is an error in the quantum channel on the basis of the number of detection paths of photons output from the beam splitter.

Abstract: The present disclosure relates to a quantum communication system. Particularly, the present disclosure relates to a device and a method for performing two-step quantum secure direct communication (QSDC) with a reduced complexity without measuring a quantum memory and a bell state of a receiver in a quantum communication system.

Abstract: In order to perform quantum secure direct communication using a high-dimensional quantum state quantum state based on polarization and phase information, a method performed by a first device in a communication system may comprise establishing a classic channel with a second device using a random access (RA) preamble and an RA response (RAR) message, receiving a forward pulse including photons in an initial quantum state from the second device, and transmitting a backward pulse representing a plurality of bits per photon by performing phase modulation and polarization modulation on the photons based on assistance of the classic channel

Abstract: The present specification provides a method by which a terminal performs federated learning with a plurality of terminals in a wireless communication system.

Abstract: The present specification provides a method for transmitting at least one beam, performed by a device, in a wireless communication system, in which the at least one beam is transmitted to another device and a measurement result of the at least one beam is received from the another device, wherein the at least one beam is a beam generated on the basis of a laser signal being incident on the metasurface, the laser signal passing through a phase controller or a delay controller before being incident on the metasurface.

Abstract: The present disclosure provides a method for one user equipment (UE) to perform federated learning with a plurality of UEs in a wireless communication system. More specifically, the method performed by the one UE comprises receiving, from a server, a channel state information reference signal (CSI-RS); transmitting, to the server, channel state information (CSI) calculated based on the CSI-RS; receiving, from the server, compression state information for determining a weight compression method of the one UE based on (i) information on a global parameter for the federated learning and (ii) channel state information of each of channels between the server and the plurality of UEs; determining the weight compression method based on (i) a difference between the global parameter and a global parameter received before a reception of the global parameter and (ii) the compression state information; and transmitting, to the server, a local parameter updated based on the determined weight compression method.

Abstract: A method and a device used in an optical wireless communication (OWC) system are provided. A transmitting terminal transmits a plurality of reference signals to a receiving terminal through each of a plurality of beams. Each of the plurality of beams may have an inhomogeneous polarization beam pattern. The receiving terminal measures signal strength and polarization with respect to the plurality of reference signals. When the receiving terminal transmits feedback information including the measured signal strength information and polarization information to the transmitting terminal, the transmitting terminal may select at least one beam among the plurality of beams on the basis of the feedback information. Alternatively, the receiving terminal may select at least one beam from among the plurality of beams, which corresponds to at least one inhomogeneous polarization beam pattern among a plurality of inhomogeneous polarization beam patterns, on the basis of the measured signal strength and polarization.

Abstract: A sender may: decompose, on the basis of a plurality of semantic elements, data into semantic element values respectively corresponding to the plurality of semantic elements; perform a first transmission including some semantic element values from among the semantic element values; and on the basis of receiving a retransmission request for the first transmission from a receiver, perform a retransmission including at least one semantic element value other than the semantic element values included in the first transmission, from among the plurality of semantic element values.

Abstract: A transmission device in a wireless communication system: determines an encoder having S outputs from among encoders supported by the transmission device, on the basis of the number B of feedback bits, wherein B=S×Q; encodes CSI through the encoder to output S real number values; determines B-bit encoded CSI including Q bits indicating the S real number values, respectively; and transmits the B-bit encoded CSI. The encoders may have different numbers of outputs from each other, and the different numbers of outputs may be predetermined for different feedback bit number ranges.

Abstract: Proposed are a method for performing federated learning in a wireless communication system, and an apparatus therefor. The method performed by a terminal may comprise the steps of: generating a Q-ary code including i) a restriction-based system part and ii) a parity part by coding restriction-based Q-ary information; determining, on the basis of a preset method, the number T of transmissions of the parity part of the Q-ary code; on the basis of specific channel information from among channel information between a plurality of terminals and a base station participating in the federated learning, allocating power to the system part and T parity parts; and transmitting, on the basis of the allocated power, the system part and the T parity parts to the base station.

Abstract: The present disclosure provides a method for reporting, by a terminal, channel state information (CSI) in a wireless communication system. More specifically, the method includes: receiving, from a base station, a pilot signal related to calculation of a quantization rule, in which the quantization rule is determined based on an empirical distribution of an encoder neural network output of the terminal; transmitting, to the base station, quantization rule information related to the quantization rule calculated based on the pilot signal; and receiving, from the base station, information on a gradient calculated based on the quantization rule information, and the quantization rule information includes information on an empirically calculated variance with respect to the empirical distribution of the encoder neural network output.