KR20230052844A - Method and apparatus for transmitting and receiving signals between a terminal and a base station in a wireless communication system - Google Patents

Abstract

The present disclosure discloses a method of operating a terminal and a base station in a wireless communication system and an apparatus supporting the same. As an example of the present disclosure, a method of operating a user equipment (UE) in a wireless communication system includes receiving a pilot symbol from a base station, channel state information (CSI) based on the received pilot symbol It may include estimating and reporting to the base station, and receiving a signal from the base station according to a direction of a beam determined based on the estimated channel state information.

Description

Method and apparatus for transmitting and receiving signals between a terminal and a base station in a wireless communication system

The following description relates to a wireless communication system, and relates to a method and apparatus for transmitting and receiving signals between a terminal and a base station.

A beam forming method and apparatus using multiple antennas based on a digital-to-analog converter (DAC)/analog-to-digital converter (ADC) used in a THz band by a terminal and a base station in a wireless communication system.

In particular, when the terminal and the base station transmit and receive signals in the THz band,

A beam forming method and apparatus for overcoming the problem of lowering the data rate and the limitation of the modulation order when using a resolution ADC/DAC.

A wireless access system is widely deployed to provide various types of communication services such as voice and data. In general, a wireless access system is a multiple access system capable of supporting communication with multiple users by sharing available system resources (bandwidth, transmission power, etc.). Examples of the multiple access system include a code division multiple access (CDMA) system, a frequency division multiple access (FDMA) system, a time division multiple access (TDMA) system, an orthogonal frequency division multiple access (OFDMA) system, and a single carrier frequency (SC-FDMA) system. division multiple access) system.

In particular, as many communication devices require large communication capacity, an enhanced mobile broadband (eMBB) communication technology compared to existing radio access technology (RAT) has been proposed. In addition, a communication system considering reliability and latency-sensitive services/UE (user equipment) as well as mMTC (massive machine type communications) providing various services anytime and anywhere by connecting multiple devices and objects has been proposed. . Various technical configurations for this have been proposed.

The present disclosure may provide a method and apparatus for transmitting and receiving signals between a terminal and a base station in a wireless communication system.

The present disclosure may provide a multi-antenna based transmission/reception method and apparatus according to antenna selective modulation in a THz band-based wireless communication system.

The technical objects to be achieved in the present disclosure are not limited to the above-mentioned matters, and other technical problems not mentioned above are common knowledge in the art to which the technical configuration of the present disclosure is applied from the embodiments of the present disclosure to be described below. can be considered by those who have

The present disclosure may provide a method and apparatus for transmitting and receiving signals between a terminal and a base station in a wireless communication system.

As an example of the present disclosure, a method of operating a user equipment (UE) in a wireless communication system includes receiving a pilot symbol from a base station, channel state information (CSI) based on the received pilot symbol It may include estimating and reporting to the base station, and receiving a signal from the base station according to a direction of a beam determined based on the estimated channel state information.

Meanwhile, the pilot symbol may be based on a single constellation.

Meanwhile, when receiving the pilot symbol based on the single constellation, the single constellation may be a reference constellation indicated by the base station and inferred by the terminal.

Meanwhile, the pilot symbol may be based on multi-constellation.

Meanwhile, when receiving the pilot symbol based on the multi-constellation, the terminal may receive the pilot symbol at least once for each constellation included in the multi-constellation or for each pre-selected partial constellation. .

Meanwhile, when the pilot symbol based on the multi-constellation is received, the channel state information transmitted by the terminal includes the average value and each channel state estimated from the pilot symbol based on the constellation. Information about the difference from information may be further included.

Meanwhile, when the pilot symbols based on the multi-constellation are received, the channel state information may be estimated as an average value for each piece of channel state information estimated from pilot symbols based on each constellation.

Meanwhile, when receiving the pilot symbol based on the multi-constellation, the channel state information may include each channel state information estimated from the pilot symbol based on each constellation.

Meanwhile, when receiving the pilot symbol based on the multi-constellation, the channel state information is a pilot based on a reference constellation having a phase value that the terminal and the base station already know or can be inferred by the base station. It may include a difference between channel state information estimated from a symbol and each channel state information estimated from pilot symbols based on other constellations.

Meanwhile, when receiving the pilot symbol based on the multi-constellation, the channel state information may include only the channel quality of a constellation point for which the estimated channel quality is determined to be greater than or equal to a preset threshold.

Meanwhile, when the pilot symbol based on the multi-constellation is received, the channel state information may be reported differently for each type of channel state information.

Meanwhile, when the channel environment is deterministic or fixed, the terminal can receive the pilot symbol based on a single constellation.

Meanwhile, the base station may dynamically select whether the pilot symbol received by the terminal is based on multi-constellation or single constellation according to channel similarity.

Meanwhile, the direction of the determined beam may be different for each bit of the signal.

Meanwhile, at least one of the pilot symbol and the signal may be transmitted based on a 1-bit DAC.

As an example of the present disclosure, in a wireless communication system, a terminal is operably connected to at least one transmitter, at least one receiver, at least one processor, and the at least one processor, and when executed, the at least one processor specifies Includes at least one memory for storing instructions for performing an operation, and the specific operation receives a pilot symbol from a base station. Based on the received pilot symbol, Channel State Information (CSI) ), and reporting the estimated channel state information to the base station.

As an example of the present disclosure, in a wireless communication system, a base station is operatively connected to at least one transmitter, at least one receiver, at least one processor, and the at least one processor, and when executed, the at least one processor specifies Includes at least one memory for storing instructions for performing an operation, wherein the specific operation transmits a pilot symbol to a terminal, channel state information (CSI, estimated from the terminal based on the pilot symbol) channel state information), and transmitting a signal to the terminal based on a direction of a beam determined based on the channel state information.

The above-described aspects of the present disclosure are only some of the preferred embodiments of the present disclosure, and various embodiments in which the technical features of the present disclosure are reflected are detailed descriptions of the present disclosure to be detailed below by those of ordinary skill in the art. It can be derived and understood based on.

The following effects may be obtained by embodiments based on the present disclosure.

According to the present disclosure, when transmitting and receiving signals in the THz band, power consumption can be reduced by using a low resolution ADC/DAC.

According to the present disclosure, it is possible to prevent a problem in which a data transmission rate is lowered when a low resolution ADC/DAC is used.

According to the present disclosure, high-order modulation is possible while using a low-resolution ADC/DAC, and a beamforming gain can be effectively obtained.

Effects obtainable in the embodiments of the present disclosure are not limited to the above-mentioned effects, and other effects not mentioned are technical fields to which the technical configuration of the present disclosure is applied from the description of the following embodiments of the present disclosure. can be clearly derived and understood by those skilled in the art. That is, unintended effects according to implementing the configuration described in the present disclosure may also be derived by those skilled in the art from the embodiments of the present disclosure.

The accompanying drawings are provided to aid understanding of the present disclosure, and may provide embodiments of the present disclosure together with a detailed description. However, the technical features of the present disclosure are not limited to specific drawings, and features disclosed in each drawing may be combined with each other to form a new embodiment. Reference numerals in each drawing may mean structural elements.
1 is a diagram illustrating an example of a communication system applied to the present disclosure.
2 is a diagram illustrating an example of a wireless device applicable to the present disclosure.
3 is a diagram illustrating another example of a wireless device applied to the present disclosure.
4 is a diagram illustrating an example of a portable device applied to the present disclosure.
5 is a diagram illustrating an example of a vehicle or autonomous vehicle to which the present disclosure applies.
6 is a diagram showing an example of a moving body applied to the present disclosure.
7 is a diagram showing an example of an XR device applied to the present disclosure.
8 is a diagram showing an example of a robot applied to the present disclosure.
9 is a diagram illustrating an example of an artificial intelligence (AI) device applied to the present disclosure.
10 is a diagram illustrating physical channels applied to the present disclosure and a signal transmission method using them.
11 is a diagram illustrating structures of a control plane and a user plane of a radio interface protocol applied to the present disclosure.
12 is a diagram illustrating a method of processing a transmission signal applied to the present disclosure.
13 is a diagram illustrating a structure of a radio frame applicable to the present disclosure.
14 is a diagram illustrating a slot structure applicable to the present disclosure.
15 is a diagram illustrating an example of a communication structure that can be provided in a 6G system applicable to the present disclosure.
16 is a diagram showing an electromagnetic spectrum applicable to the present disclosure.
17 is a diagram illustrating a THz communication method applicable to the present disclosure.
18 is a diagram illustrating a THz wireless communication transceiver applicable to the present disclosure.
19 is a diagram illustrating a THz signal generation method applicable to the present disclosure.
20 is a diagram illustrating a wireless communication transceiver applicable to the present disclosure.
21 is a diagram illustrating a transmitter structure applicable to the present disclosure.
22 is a diagram illustrating a modulator structure applicable to the present disclosure.
23 is a block diagram of a transmitter applicable to the present disclosure.
24 is a diagram illustrating an antenna configuration applicable to the present disclosure.
25 to 28 are diagrams illustrating single-panel-based multi-antenna configurations applicable to the present disclosure.
29 to 32 are diagrams illustrating multi-panel-based multi-antenna configurations applicable to the present disclosure.
33 is a diagram illustrating a multi-panel configuration for a phase-defined antenna-based modulation scheme applicable to the present disclosure.
34 is a diagram showing plane waves of multiple panels applicable to the present disclosure.
35 is a diagram illustrating a symbol configuration applicable to the present disclosure.
36 is a diagram illustrating a pilot symbol transmission method according to an embodiment of the present disclosure.
37 is a diagram illustrating an operating method of a receiving end according to an embodiment of the present disclosure.
38 is a diagram illustrating an operation method of a transmitter according to an embodiment of the present disclosure.
39 is a block diagram of a transmitter according to an embodiment of the present disclosure.

The following embodiments are those that combine elements 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 in a form not combined with other components or features. In addition, an embodiment of the present disclosure may be configured by combining some elements and/or features. 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.

In the description of the drawings, procedures or steps that may obscure the gist of the present disclosure have not been described, and procedures or steps that can be understood by those skilled in the art have not been described.

Throughout the specification, when a part is said to "comprising" or "including" a certain element, it means that it may further include other elements, not excluding other elements, unless otherwise stated. do. In addition, terms such as “… unit”, “… unit”, and “module” described in the specification mean a unit that processes at least one function or operation, which is hardware or software or a combination of hardware and software. can be implemented as Also, "a or an", "one", "the" and similar related words in the context of describing the present disclosure (particularly in the context of the claims below) Unless indicated or otherwise clearly contradicted by context, both the singular and the plural can be used.

In this specification, the embodiments of the present disclosure have been described with a focus on a data transmission/reception relationship between a base station and a mobile station. Here, a base station has meaning as a terminal node of a network that directly communicates with a mobile station. A specific operation described as being performed by a base station in this document may be performed by an upper node of the base station in some cases.

That is, in a network composed of a plurality of network nodes including a base station, various operations performed for communication with a mobile station may be performed by the base station or network nodes other than the base station. At this time, the 'base station' is a term such as a fixed station, Node B, eNode B, gNode B, ng-eNB, advanced base station (ABS), or access point. can be replaced by

In addition, in the embodiments of the present disclosure, a terminal includes a user equipment (UE), a mobile station (MS), a subscriber station (SS), a mobile subscriber station (MSS), It may be replaced with terms such as mobile terminal or advanced mobile station (AMS).

In addition, the transmitting end refers to a fixed and/or mobile node providing data service or voice service, and the receiving end refers to a fixed and/or mobile node receiving data service or voice service. Therefore, in the case of uplink, the mobile station can be a transmitter and the base station can be a receiver. Similarly, in the case of downlink, the mobile station may be a receiving end and the base station may be a transmitting end.

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

In addition, embodiments of the present disclosure may be applied to other wireless access systems, and are not limited to the above-described systems. For example, it may also be applicable to a system applied after the 3GPP 5G NR system, and is not limited to a specific system.

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

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 in conjunction with the accompanying drawings is intended to describe 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 practiced.

In addition, specific terms used in the embodiments of the present disclosure are provided to aid understanding of the present disclosure, and the use of these specific terms may be changed in other forms without departing from the technical spirit of the present disclosure.

The following technologies include code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), and the like. It can be applied to various wireless access systems.

For clarity, the following description is based on a 3GPP communication system (eg, LTE, NR, etc.), but the technical spirit of the present invention is not limited thereto. LTE may refer to technology after 3GPP TS 36.xxx Release 8. In detail, 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 mean technology after TS 38.xxx Release 15. 3GPP 6G may mean technology after TS Release 17 and/or Release 18. "xxx" means standard document detail number. LTE/NR/6G may be collectively referred to as a 3GPP system.

For background art, terms, abbreviations, etc. used in the present disclosure, reference may be made to matters described in standard documents published prior to the present invention. As an example, 36.xxx and 38.xxx standard documents may be referred to.

Communication systems applicable to the present disclosure

Although not limited thereto, 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 / connection (eg, 5G) between devices. there is.

Hereinafter, it will be exemplified in more detail with reference to the drawings. In the following drawings/description, the same reference numerals may represent the same or corresponding hardware blocks, software blocks or functional blocks unless otherwise specified.

1 is a diagram illustrating an example of a communication system applied to the present disclosure.

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 means a device that performs communication using a radio access technology (eg, 5G NR, LTE), and may be referred to as a communication/wireless/5G device. Although not limited thereto, the wireless device includes a robot 100a, a vehicle 100b-1 and 100b-2, an extended reality (XR) device 100c, a hand-held device 100d, and a home appliance. appliance) 100e, Internet of Thing (IoT) device 100f, and artificial intelligence (AI) 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 inter-vehicle communication, and the like. Here, the vehicles 100b-1 and 100b-2 may include an unmanned aerial vehicle (UAV) (eg, a drone). The XR device 100c includes augmented reality (AR)/virtual reality (VR)/mixed reality (MR) devices, and includes a head-mounted device (HMD), a head-up display (HUD) installed in a vehicle, a television, It may be implemented in the form of smart phones, computers, wearable devices, home appliances, digital signage, vehicles, robots, and the like. The mobile device 100d may include a smart phone, a smart pad, a wearable device (eg, a smart watch, a smart glass), a computer (eg, a laptop computer), and the like. The home appliance 100e may include a TV, a refrigerator, a washing machine, and the like. The IoT device 100f may include a sensor, a smart meter, and the like. For example, the base station 120 and the network 130 may also be implemented as a wireless device, and a specific wireless device 120a may operate as a base station/network node to other wireless devices.

The wireless devices 100a to 100f may be connected to the network 130 through the base station 120 . AI technology may be applied to the wireless devices 100a to 100f, and the wireless devices 100a to 100f may be connected to the AI server 100g through the network 130. The network 130 may be configured using a 3G network, a 4G (eg LTE) network, or a 5G (eg NR) network. The wireless devices 100a to 100f may communicate with each other through the base station 120/network 130, but communicate directly without going through the base station 120/network 130 (e.g., sidelink communication). You may. For example, the vehicles 100b-1 and 100b-2 may perform direct communication (eg, vehicle to vehicle (V2V)/vehicle to everything (V2X) communication). In addition, the IoT device 100f (eg, sensor) may directly communicate with other IoT devices (eg, sensor) or other wireless devices 100a to 100f.

Wireless communication/connection 150a, 150b, and 150c may be performed between the wireless devices 100a to 100f/base station 120 and the base station 120/base station 120. Here, wireless communication/connection includes various types of uplink/downlink communication 150a, sidelink communication 150b (or D2D communication), and inter-base station communication 150c (eg relay, integrated access backhaul (IAB)). This can be done through radio access technology (eg 5G NR). Through the wireless communication/connection 150a, 150b, and 150c, a wireless device and a base station/wireless device, and a base station and a base station can transmit/receive radio signals to each other. For example, the wireless communication/connections 150a, 150b, and 150c may transmit/receive signals through various physical channels. To this end, based on various proposals of the present disclosure, various configuration information setting processes for transmitting / receiving radio signals, various signal processing processes (eg, channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.) At least a part of a resource allocation process may be performed.

Wireless devices applicable to the present disclosure

2 is a diagram illustrating an example of a wireless device applicable to the present disclosure.

Referring to FIG. 2 , a first wireless device 200a and a second wireless device 200b may transmit and receive radio signals through various wireless access technologies (eg, LTE and NR). Here, {the first wireless device 200a, the second wireless device 200b} denotes the {wireless device 100x and the base station 120} of FIG. 1 and/or the {wireless device 100x and the wireless device 100x. } can correspond.

The first wireless device 200a includes one or more processors 202a and one or more memories 204a, and may further include one or more transceivers 206a and/or one or more antennas 208a. The processor 202a controls the memory 204a and/or the transceiver 206a and may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flow diagrams disclosed herein. For example, the processor 202a may process information in the memory 204a to generate first information/signal, and transmit a radio signal including the first information/signal through the transceiver 206a. In addition, the processor 202a may receive a radio signal including the second information/signal through the transceiver 206a and store information obtained from signal processing of the second information/signal in the memory 204a. The memory 204a may be connected to the processor 202a and may store various information related to the operation of the processor 202a. For example, memory 204a may perform some or all of the processes controlled by processor 202a, or instructions for performing the descriptions, functions, procedures, suggestions, methods, and/or flowcharts of operations disclosed herein. It may store software codes including them. Here, the processor 202a and the memory 204a may be part of a communication modem/circuit/chip designed to implement a wireless communication technology (eg, LTE, NR). The transceiver 206a may be coupled to the processor 202a and may transmit and/or receive wireless signals through one or more antennas 208a. The transceiver 206a may include a transmitter and/or a receiver. The transceiver 206a may be used interchangeably with a radio frequency (RF) unit. In the present disclosure, a wireless device may mean a communication modem/circuit/chip.

The second wireless device 200b includes one or more processors 202b, one or more memories 204b, and may further include one or more transceivers 206b and/or one or more antennas 208b. The processor 202b controls the memory 204b and/or the transceiver 206b and may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flow diagrams disclosed herein. For example, the processor 202b may process information in the memory 204b to generate third information/signal, and transmit a radio signal including the third information/signal through the transceiver 206b. In addition, the processor 202b may receive a radio signal including the fourth information/signal through the transceiver 206b and store information obtained from signal processing of the fourth information/signal in the memory 204b. The memory 204b may be connected to the processor 202b and may store various information related to the operation of the processor 202b. For example, the memory 204b may perform some or all of the processes controlled by the processor 202b, or instructions for performing the descriptions, functions, procedures, suggestions, methods, and/or flowcharts of operations disclosed herein. It may store software codes including them. Here, the processor 202b and the memory 204b may be part of a communication modem/circuit/chip designed to implement a wireless communication technology (eg, LTE, NR). The transceiver 206b may be coupled to the processor 202b and may transmit and/or receive wireless signals through one or more antennas 208b. The transceiver 206b may include a transmitter and/or a receiver. The transceiver 206b may be used interchangeably with an RF unit. In the present disclosure, a wireless device may mean a communication modem/circuit/chip.

Hereinafter, hardware elements of the wireless devices 200a and 200b will be described in more detail. Although not limited to this, one or more protocol layers may be implemented by one or more processors 202a, 202b. For example, the one or more processors 202a and 202b may include one or more layers (eg, PHY (physical), MAC (media access control), RLC (radio link control), PDCP (packet data convergence protocol), RRC (radio resource) control) and functional layers such as service data adaptation protocol (SDAP). One or more processors 202a, 202b may generate one or more protocol data units (PDUs) and/or one or more service data units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and/or operational flow charts disclosed herein. can create One or more processors 202a, 202b may generate messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and/or operational flow diagrams disclosed herein. One or more processors 202a, 202b generate PDUs, SDUs, messages, control information, data or signals (eg, baseband signals) containing information according to the functions, procedures, proposals and/or methods disclosed herein , may be provided to one or more transceivers 206a and 206b. One or more processors 202a, 202b may receive signals (eg, baseband signals) from one or more transceivers 206a, 206b, and descriptions, functions, procedures, suggestions, methods, and/or flowcharts of operations disclosed herein PDUs, SDUs, messages, control information, data or information can be obtained according to these.

One or more processors 202a, 202b may be referred to as a controller, microcontroller, microprocessor or microcomputer. One or more processors 202a, 202b may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more application specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field programmable gate arrays (FPGAs). may be included in one or more processors 202a and 202b. The descriptions, functions, procedures, proposals, methods and/or operational 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, and the like. Firmware or software configured to perform the descriptions, functions, procedures, proposals, methods and/or operational flow charts disclosed in this document may be included in one or more processors 202a or 202b or stored in one or more memories 204a or 204b. It can be driven by the above processors 202a and 202b. The descriptions, functions, procedures, suggestions, methods and/or operational flow charts disclosed in this document may be implemented using firmware or software in the form of codes, instructions and/or sets of instructions.

One or more memories 204a, 204b may be coupled to one or more processors 202a, 202b and may store various types of data, signals, messages, information, programs, codes, instructions and/or instructions. One or more memories 204a, 204b may include read only memory (ROM), random access memory (RAM), erasable programmable read only memory (EPROM), flash memory, hard drive, registers, cache memory, computer readable storage media, and/or It may consist of a combination of these. One or more memories 204a, 204b may be located internally and/or externally to one or more processors 202a, 202b. In addition, one or more memories 204a, 204b may be connected to one or more processors 202a, 202b through various technologies such as wired or wireless connections.

One or more transceivers 206a, 206b may transmit user data, control information, radio signals/channels, etc. referred to in the methods and/or operational flow charts of this document to one or more other devices. One or more transceivers 206a, 206b may receive user data, control information, radio signals/channels, etc. referred to in descriptions, functions, procedures, proposals, methods and/or operational flow charts, etc. disclosed herein from one or more other devices. there is. For example, one or more transceivers 206a and 206b may be connected to one or more processors 202a and 202b and transmit and receive radio signals. For example, one or more processors 202a, 202b may control one or more transceivers 206a, 206b to transmit user data, control information, or radio signals to one or more other devices. In addition, one or more processors 202a, 202b may control one or more transceivers 206a, 206b to receive user data, control information, or radio signals from one or more other devices. In addition, one or more transceivers 206a, 206b may be coupled to one or more antennas 208a, 208b, and one or more transceivers 206a, 206b may be connected to one or more antennas 208a, 208b to achieve the descriptions, functions disclosed in this document. , procedures, proposals, methods and / or operation flowcharts, etc. can be set to transmit and receive user data, control information, radio signals / channels, etc. In this document, one or more antennas may be a plurality of physical antennas or a plurality of logical antennas (eg, antenna ports). One or more transceivers (206a, 206b) in order to process the received user data, control information, radio signal / channel, etc. using one or more processors (202a, 202b), the received radio signal / channel, etc. in the RF band signal It can be converted into a baseband signal. One or more transceivers 206a and 206b may convert user data, control information, and radio signals/channels processed by one or more processors 202a and 202b from baseband signals to RF band signals. To this end, one or more transceivers 206a, 206b may include (analog) oscillators and/or filters.

Wireless device structure applicable to the present disclosure

3 is a diagram illustrating another example of a wireless device applied to the present disclosure.

Referring to FIG. 3, a wireless device 300 corresponds to the wireless devices 200a and 200b of FIG. 2, and includes various elements, components, units/units, and/or modules. ) can be configured. For example, the wireless device 300 may include a communication unit 310, a control unit 320, a memory unit 330, and an additional element 340. The communication unit may include communication circuitry 312 and transceiver(s) 314 . For example, communication circuitry 312 may include one or more processors 202a, 202b of FIG. 2 and/or one or more memories 204a, 204b. For example, transceiver(s) 314 may include one or more transceivers 206a, 206b of FIG. 2 and/or one or more antennas 208a, 208b. The control unit 320 is electrically connected to the communication unit 310, the memory unit 330, and the additional element 340 and controls overall operations of the wireless device. For example, the control unit 320 may control electrical/mechanical operations of the wireless device based on programs/codes/commands/information stored in the memory unit 330. In addition, the control unit 320 transmits the information stored in the memory unit 330 to the outside (eg, another communication device) through the communication unit 310 through a wireless/wired interface, or transmits the information stored in the memory unit 330 to the outside (eg, another communication device) through the communication unit 310. Information received through a wireless/wired interface from other communication devices) may be stored in the memory unit 330 .

The additional element 340 may be configured in various ways according to the type of wireless device. For example, the additional element 340 may include at least one of a power unit/battery, an input/output unit, a driving unit, and a computing unit. Although not limited thereto, the wireless device 300 may be a robot (FIG. 1, 100a), a vehicle (FIG. 1, 100b-1, 100b-2), an XR device (FIG. 1, 100c), a mobile device (FIG. 1, 100d) ), home appliances (FIG. 1, 100e), IoT devices (FIG. 1, 100f), digital broadcasting terminals, hologram devices, public safety devices, MTC devices, medical devices, fintech devices (or financial devices), security devices, climate/ It may be implemented in the form of an environment device, an AI server/device (FIG. 1, 140), a base station (FIG. 1, 120), a network node, and the like. Wireless devices can be mobile or used in a fixed location depending on the use-case/service.

In FIG. 3 , various elements, components, units/units, and/or modules in the wireless device 300 may be entirely interconnected through a wired interface or at least partially connected wirelessly through the communication unit 310 . For example, in the wireless device 300, the control unit 320 and the communication unit 310 are connected by wire, and the control unit 320 and the first units (eg, 130 and 140) are connected wirelessly through the communication unit 310. can be connected Additionally, each element, component, unit/unit, and/or module within wireless device 300 may further include one or more elements. For example, the control unit 320 may be composed of one or more processor sets. For example, the control unit 320 may include a set of a communication control processor, an application processor, an electronic control unit (ECU), a graphic processing processor, a memory control processor, and the like. As another example, the memory unit 330 may include RAM, dynamic RAM (DRAM), ROM, flash memory, volatile memory, non-volatile memory, and/or combinations thereof. can be configured.

Mobile device to which the present disclosure is applicable

4 is a diagram illustrating an example of a portable device applied to the present disclosure.

4 illustrates a portable device applied to the present disclosure. A portable device may include a smart phone, a smart pad, a wearable device (eg, a smart watch, a smart glass), and a portable computer (eg, a laptop computer). A mobile device may be referred to as a mobile station (MS), a user terminal (UT), a mobile subscriber station (MSS), a subscriber station (SS), an advanced mobile station (AMS), or a wireless terminal (WT).

Referring to FIG. 4 , a portable device 400 includes an antenna unit 408, a communication unit 410, a control unit 420, a memory unit 430, a power supply unit 440a, an interface unit 440b, and an input/output unit 440c. ) may be included. The antenna unit 408 may be configured as part of the communication unit 410 . Blocks 410 to 430/440a to 440c respectively correspond to blocks 310 to 330/340 of FIG. 3 .

The communication unit 410 may transmit/receive signals (eg, data, control signals, etc.) with other wireless devices and base stations. The controller 420 may perform various operations by controlling components of the portable device 400 . The controller 420 may include an application processor (AP). The memory unit 430 may store data/parameters/programs/codes/commands necessary for driving the portable device 400 . Also, the memory unit 430 may store input/output data/information. The power supply unit 440a supplies power to the portable device 400 and may include a wired/wireless charging circuit, a battery, and the like. The interface unit 440b may support connection between the mobile device 400 and other external devices. The interface unit 440b may include various ports (eg, audio input/output ports and video input/output ports) for connection with external devices. The input/output unit 440c may receive or output image information/signal, audio information/signal, data, and/or information input from a user. The input/output unit 440c may include a camera, a microphone, a user input unit, a display unit 440d, a speaker, and/or a haptic module.

For example, in the case of data communication, the input/output unit 440c acquires information/signals (eg, touch, text, voice, image, video) input from the user, and the acquired information/signals are stored in the memory unit 430. can be stored The communication unit 410 may convert the information/signal stored in the memory into a wireless signal, and directly transmit the converted wireless signal to another wireless device or to a base station. In addition, the communication unit 410 may receive a radio signal from another wireless device or base station and then restore the received radio signal to original information/signal. After the restored information/signal is stored in the memory unit 430, it may be output in various forms (eg, text, voice, image, video, or haptic) through the input/output unit 440c.

Types of wireless devices to which this disclosure is applicable

5 is a diagram illustrating an example of a vehicle or autonomous vehicle to which the present disclosure applies.

5 illustrates a vehicle or autonomous vehicle to which the present disclosure is applied. A vehicle or an autonomous vehicle may be implemented as a mobile robot, vehicle, train, manned/unmanned aerial vehicle (AV), ship, etc., and is not limited to a vehicle type.

Referring to FIG. 5 , a vehicle or autonomous vehicle 500 includes an antenna unit 508, a communication unit 510, a control unit 520, a driving unit 540a, a power supply unit 540b, a sensor unit 540c, and an autonomous driving unit. A portion 540d may be included. The antenna unit 550 may be configured as a part of the communication unit 510 . Blocks 510/530/540a to 540d respectively correspond to blocks 410/430/440 of FIG. 4 .

The communication unit 510 may transmit/receive signals (eg, data, control signals, etc.) with external devices such as other vehicles, base stations (eg, base stations, roadside base units, etc.), servers, and the like. The controller 520 may perform various operations by controlling elements of the vehicle or autonomous vehicle 500 . The controller 520 may include an electronic control unit (ECU). The driving unit 540a may drive the vehicle or autonomous vehicle 500 on the ground. The driving unit 540a may include an engine, a motor, a power train, a wheel, a brake, a steering device, and the like. The power supply unit 540b supplies power to the vehicle or autonomous vehicle 500, and may include a wired/wireless charging circuit, a battery, and the like. The sensor unit 540c may obtain vehicle conditions, surrounding environment information, and user information. The sensor unit 540c includes an inertial measurement unit (IMU) sensor, a collision sensor, a wheel sensor, a speed sensor, an inclination sensor, a weight detection sensor, a heading sensor, a position module, and a vehicle forward. /Can include a reverse sensor, battery sensor, fuel sensor, tire sensor, steering sensor, temperature sensor, humidity sensor, ultrasonic sensor, illuminance sensor, pedal position sensor, and the like. The autonomous driving unit 540d includes a technology for maintaining the driving lane, a technology for automatically adjusting the speed such as adaptive cruise control, a technology for automatically driving along a predetermined route, and a technology for automatically setting a route when a destination is set and driving. technology can be implemented.

For example, the communication unit 510 may receive map data, traffic information data, and the like from an external server. The autonomous driving unit 540d may generate an autonomous driving route and a driving plan based on the acquired data. The control unit 520 may control the driving unit 540a so that the vehicle or autonomous vehicle 500 moves along the autonomous driving route according to the driving plan (eg, speed/direction adjustment). During autonomous driving, the communication unit 510 may non/periodically obtain the latest traffic information data from an external server and obtain surrounding traffic information data from surrounding vehicles. In addition, during autonomous driving, the sensor unit 540c may obtain vehicle state and surrounding environment information. The autonomous driving unit 540d may update an autonomous driving route and a driving plan based on newly acquired data/information. The communication unit 510 may transmit information about a vehicle location, an autonomous driving route, a driving plan, and the like to an external server. The external server may predict traffic information data in advance using AI technology based on information collected from the vehicle or self-driving vehicles, and may provide the predicted traffic information data to the vehicle or self-driving vehicles.

6 is a diagram showing an example of a moving body applied to the present disclosure.

Referring to FIG. 6 , a mobile body applied to the present disclosure may be implemented as at least one of a vehicle, a train, an air vehicle, and a ship. In addition, the mobile body applied to the present disclosure may be implemented in other forms, and is not limited to the above-described embodiment.

At this time, referring to FIG. 6 , the mobile body 600 may include a communication unit 610, a control unit 620, a memory unit 630, an input/output unit 640a, and a position measurement unit 640b. Here, blocks 610 to 630/640a to 640b respectively correspond to blocks 310 to 330/340 of FIG. 3 .

The communication unit 610 may transmit/receive signals (eg, data, control signals, etc.) with other mobile bodies or external devices such as base stations. The controller 620 may perform various operations by controlling components of the moving body 600 . The memory unit 630 may store data/parameters/programs/codes/commands supporting various functions of the moving object 600 . The input/output unit 640a may output an AR/VR object based on information in the memory unit 630. The input/output unit 640a may include a HUD. The location measurement unit 640b may obtain location information of the moving object 600 . The location information may include absolute location information of the moving object 600, location information within a driving line, acceleration information, and location information with surrounding vehicles. The location measurement unit 640b may include GPS and various sensors.

For example, the communication unit 610 of the moving object 600 may receive map information, traffic information, and the like from an external server and store them in the memory unit 630 . The location measuring unit 640b may acquire moving object location information through GPS and various sensors and store it in the memory unit 630 . The controller 620 may generate a virtual object based on map information, traffic information, location information of the moving object, and the like, and the input/output unit 640a may display the created virtual object on a window in the moving object (651, 652). In addition, the controller 620 may determine whether the moving object 600 is normally operated within the traveling line based on the moving object location information. When the moving object 600 abnormally departs from the driving line, the control unit 620 may display a warning on a window in the moving object through the input/output unit 640a. In addition, the control unit 620 may broadcast a warning message about driving abnormality to nearby moving objects through the communication unit 610 . Depending on the circumstances, the controller 620 may transmit location information of the moving object and information about driving/moving object abnormality to related organizations through the communication unit 610 .

7 is a diagram showing an example of an XR device applied to the present disclosure. The XR device may be implemented as an HMD, a head-up display (HUD) provided in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance, a digital signage, a vehicle, a robot, and the like.

Referring to FIG. 7 , an XR device 700a may include a communication unit 710, a control unit 720, a memory unit 730, an input/output unit 740a, a sensor unit 740b, and a power supply unit 740c. . Here, blocks 710 to 730/740a to 740c may respectively correspond to blocks 310 to 330/340 of FIG. 3 .

The communication unit 710 may transmit/receive signals (eg, media data, control signals, etc.) with external devices such as other wireless devices, portable devices, or media servers. Media data may include video, image, sound, and the like. The controller 720 may perform various operations by controlling components of the XR device 700a. For example, the controller 720 may be configured to control and/or perform procedures such as video/image acquisition, (video/image) encoding, and metadata generation and processing. The memory unit 730 may store data/parameters/programs/codes/commands necessary for driving the XR device 700a/creating an XR object.

The input/output unit 740a may obtain control information, data, etc. from the outside and output the created XR object. The input/output unit 740a may include a camera, a microphone, a user input unit, a display unit, a speaker, and/or a haptic module. The sensor unit 740b may obtain XR device status, surrounding environment information, user information, and the like. The sensor unit 740b includes a proximity sensor, an illuminance sensor, an acceleration sensor, a magnetic sensor, a gyro sensor, an inertial sensor, a red green blue (RGB) sensor, an infrared (IR) sensor, a fingerprint recognition sensor, an ultrasonic sensor, an optical sensor, a microphone, and a / or radar, etc. may be included. The power supply unit 740c supplies power to the XR device 700a and may include a wired/wireless charging circuit, a battery, and the like.

For example, the memory unit 730 of the XR device 700a may include information (eg, data, etc.) necessary for generating an XR object (eg, AR/VR/MR object). The input/output unit 740a may obtain a command to operate the XR device 700a from a user, and the controller 720 may drive the XR device 700a according to the user's driving command. For example, when a user tries to watch a movie, news, etc. through the XR device 700a, the controller 720 transmits content request information through the communication unit 730 to another device (eg, the mobile device 700b) or can be sent to the media server. The communication unit 730 may download/stream content such as movies and news from other devices (eg, the mobile device 700b) or a media server to the memory unit 730 . The control unit 720 controls and/or performs procedures such as video/image acquisition, (video/image) encoding, metadata generation/processing, etc. for the content, and acquires the content through the input/output unit 740a/sensor unit 740b. An XR object may be created/output based on information about a surrounding space or a real object.

In addition, the XR device 700a is wirelessly connected to the mobile device 700b through the communication unit 710, and the operation of the XR device 700a may be controlled by the mobile device 700b. For example, the mobile device 700b may act as a controller for the XR device 700a. To this end, the XR device 700a may obtain 3D location information of the portable device 700b, and then generate and output an XR object corresponding to the portable device 700b.

8 is a diagram showing an example of a robot applied to the present disclosure. For example, robots may be classified into industrial, medical, household, military, and the like according to the purpose or field of use. At this time, referring to FIG. 8 , the robot 800 may include a communication unit 810, a control unit 820, a memory unit 830, an input/output unit 840a, a sensor unit 840b, and a driving unit 840c. . Here, blocks 810 to 830/840a to 840c may respectively correspond to blocks 310 to 330/340 of FIG. 3 .

The communication unit 810 may transmit/receive signals (eg, driving information, control signals, etc.) with external devices such as other wireless devices, other robots, or control servers. The controller 820 may perform various operations by controlling components of the robot 800 . The memory unit 830 may store data/parameters/programs/codes/commands supporting various functions of the robot 800. The input/output unit 840a may obtain information from the outside of the robot 800 and output the information to the outside of the robot 800 . The input/output unit 840a may include a camera, a microphone, a user input unit, a display unit, a speaker, and/or a haptic module.

The sensor unit 840b may obtain internal information of the robot 800, surrounding environment information, user information, and the like. The sensor unit 840b 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, an optical sensor, a microphone, a radar, and the like.

The driving unit 840c may perform various physical operations such as moving a robot joint. In addition, the driving unit 840c may make the robot 800 drive on the ground or fly in the air. The driving unit 840c may include actuators, motors, wheels, brakes, propellers, and the like.

9 is a diagram illustrating an example of an AI device applied to the present disclosure. As an example, AI devices include TVs, projectors, smartphones, PCs, laptops, digital broadcasting terminals, tablet PCs, wearable devices, set-top boxes (STBs), radios, washing machines, refrigerators, digital signage, robots, vehicles, etc. It may be implemented as a device or a movable device.

Referring to FIG. 9, the AI device 900 includes a communication unit 910, a control unit 920, a memory unit 930, an input/output unit 940a/940b, a running processor unit 940c, and a sensor unit 940d. can include Blocks 910 to 930/940a to 940d may respectively correspond to blocks 310 to 330/340 of FIG. 3 .

The communication unit 910 communicates wired and wireless signals (eg, sensor information, user data) with external devices such as other AI devices (eg, FIG. 1, 100x, 120, and 140) or AI servers (Fig. input, learning model, control signal, etc.) can be transmitted and received. To this end, the communication unit 910 may transmit information in the memory unit 930 to an external device or transmit a signal received from the external device to the memory unit 930 .

The controller 920 may determine at least one executable operation of the AI device 900 based on information determined or generated using a data analysis algorithm or a machine learning algorithm. And, the controller 920 may perform the determined operation by controlling components of the AI device 900 . For example, the controller 920 may request, retrieve, receive, or utilize data from the learning processor unit 940c or the memory unit 930, and may perform a predicted operation among at least one feasible operation or an operation determined to be desirable. Components of the AI device 900 may be controlled to execute an operation. In addition, the control unit 920 collects history information including user feedback on the operation contents or operation of the AI device 900 and stores it in the memory unit 930 or the running processor unit 940c, or the AI server ( 1, 140) can be transmitted to an external device. The collected history information can be used to update the learning model.

The memory unit 930 may store data supporting various functions of the AI device 900 . For example, the memory unit 930 may store data obtained from the input unit 940a, data obtained from the communication unit 910, output data from the learning processor unit 940c, and data obtained from the sensing unit 940. Also, the memory unit 930 may store control information and/or software codes required for operation/execution of the controller 920 .

The input unit 940a may acquire various types of data from the outside of the AI device 900 . For example, the input unit 920 may obtain learning data for model learning and input data to which the learning model is to be applied. The input unit 940a may include a camera, a microphone, and/or a user input unit. The output unit 940b may generate an output related to sight, hearing, or touch. The output unit 940b may include a display unit, a speaker, and/or a haptic module. The sensing unit 940 may obtain at least one of internal information of the AI device 900, surrounding environment information of the AI device 900, and user information by using various sensors. The sensing unit 940 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, an optical sensor, a microphone, and/or a radar. there is.

The learning processor unit 940c may learn a model composed of an artificial neural network using learning data. The running processor unit 940c may perform AI processing together with the running processor unit of the AI server (FIG. 1, 140). The learning processor unit 940c may process information received from an external device through the communication unit 910 and/or information stored in the memory unit 930 . In addition, the output value of the learning processor unit 940c may be transmitted to an external device through the communication unit 910 and/or stored in the memory unit 930.

Physical channels and general signal transmission

In a wireless access system, a terminal may receive information from a base station through downlink (DL) and transmit information to the base station through uplink (UL). Information transmitted and received between the base station and the terminal includes general data information and various control information, and there are various physical channels according to the type/use of the information transmitted and received by the base station and the terminal.

10 is a diagram illustrating physical channels applied to the present disclosure and a signal transmission method using them.

In the power-off state, the power is turned on again or the terminal newly entered the cell performs an initial cell search operation such as synchronizing with the base station in step S1011. To this end, the terminal may receive a primary synchronization channel (P-SCH) and a secondary synchronization channel (S-SCH) from the base station to synchronize with the base station and obtain information such as a cell ID. .

Thereafter, the terminal may acquire intra-cell broadcast information by receiving a physical broadcast channel (PBCH) signal from the base station. Meanwhile, the terminal may check the downlink channel state by receiving a downlink reference signal (DL RS) in the initial cell search step. After completing the initial cell search, the UE receives a physical downlink control channel (PDCCH) and a physical downlink control channel (PDSCH) according to the physical downlink control channel information in step S1012, Specific system information can be obtained.

Thereafter, the terminal may perform a random access procedure such as steps S1013 to S1016 in order to complete access to the base station. To this end, the UE transmits a preamble through a physical random access channel (PRACH) (S1013), and RAR for the preamble through a physical downlink control channel and a physical downlink shared channel corresponding thereto (S1013). random access response) may be received (S1014). The UE transmits a physical uplink shared channel (PUSCH) using scheduling information in the RAR (S1015), and performs a contention resolution procedure such as receiving a physical downlink control channel signal and a corresponding physical downlink shared channel signal (S1015). ) can be performed (S1016).

After performing the procedure as described above, the terminal receives a physical downlink control channel signal and/or a physical downlink shared channel signal as a general uplink/downlink signal transmission procedure (S1017) and physical uplink shared channel (physical uplink shared channel). channel, PUSCH) signal and/or physical uplink control channel (PUCCH) signal may be transmitted (S1018).

Control information transmitted from the terminal to the base station is collectively referred to as uplink control information (UCI). UCI is HARQ-ACK/NACK (hybrid automatic repeat and request acknowledgment/negative-ACK), SR (scheduling request), CQI (channel quality indication), PMI (precoding matrix indication), RI (rank indication), BI (beam indication) ) information, etc. In this case, UCI is generally transmitted periodically through PUCCH, but may be transmitted through PUSCH according to an embodiment (eg, when control information and traffic data are to be simultaneously transmitted). In addition, the UE may aperiodically transmit UCI through the PUSCH according to a request/instruction of the network.

11 is a diagram illustrating structures of a control plane and a user plane of a radio interface protocol applied to the present disclosure.

Referring to FIG. 11 , Entity 1 may be a user equipment (UE). In this case, the terminal may be at least one of a wireless device, a portable device, a vehicle, a mobile device, an XR device, a robot, and an AI to which the present disclosure is applied in FIGS. 1 to 9 described above. In addition, a terminal refers to a device to which the present disclosure can be applied, and may not be limited to a specific device or device.

Entity 2 may be a base station. In this case, the base station may be at least one of eNB, gNB, and ng-eNB. Also, a base station may refer to a device that transmits a downlink signal to a terminal, and may not be limited to a specific type or device. That is, the base station may be implemented in various forms or types, and may not be limited to a specific form.

Entity 3 may be a network device or a device that performs a network function. In this case, the network device may be a core network node (eg, a mobility management entity (MME), an access and mobility management function (AMF), etc.) that manages mobility. Also, the network function may refer to a function implemented to perform the network function, and entity 3 may be a device to which the function is applied. That is, entity 3 may refer to a function or device that performs a network function, and is not limited to a specific type of device.

The control plane may refer to a path through which control messages used by a user equipment (UE) and a network to manage a call are transmitted. Also, the user plane may refer to a path through which data generated in the application layer, for example, voice data or Internet packet data, is transmitted. In this case, the physical layer, which is the first layer, may provide an information transfer service to an upper layer using a physical channel. The physical layer is connected to the upper medium access control layer through a transport channel. At this time, data may move between the medium access control layer and the physical layer through the transport channel. Data may move between physical layers of a transmitting side and a receiving side through a physical channel. At this time, the physical channel uses time and frequency as radio resources.

A medium access control (MAC) layer of the second layer provides services to a radio link control (RLC) layer, which is an upper layer, through a logical channel. The RLC layer of the second layer may support reliable data transmission. The function of the RLC layer may be implemented as a function block inside the MAC. A packet data convergence protocol (PDCP) layer of the second layer may perform a header compression function that reduces unnecessary control information in order to efficiently transmit IP packets such as IPv4 or IPv6 in a narrow bandwidth air interface. . A radio resource control (RRC) layer located at the bottom of the third layer is defined only in the control plane. The RRC layer may be in charge of control of logical channels, transport channels, and physical channels in relation to configuration, re-configuration, and release of radio bearers (RBs). An RB may refer to a service provided by the second layer for data transmission between a terminal and a network. To this end, the RRC layer of the terminal and the network may exchange RRC messages with each other. A non-access stratum (NAS) layer above the RRC layer may perform functions such as session management and mobility management. One cell constituting the base station may be set to one of various bandwidths to provide downlink or uplink transmission services to several terminals. Different cells may be configured to provide different bandwidths. Downlink transport channels for transmitting data from the network to the terminal include a broadcast channel (BCH) for transmitting system information, a paging channel (PCH) for transmitting paging messages, and a shared channel (SCH) for transmitting user traffic or control messages. there is. Traffic or control messages of a downlink multicast or broadcast service may be transmitted through a downlink SCH or may be transmitted through a separate downlink multicast channel (MCH). Meanwhile, uplink transport channels for transmitting data from a terminal to a network include a random access channel (RACH) for transmitting an initial control message and an uplink shared channel (SCH) for transmitting user traffic or control messages. Logical channels located above the transport channel and mapped to the transport channel include a broadcast control channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH), a multicast control channel (MCCH), and a multicast control channel (MTCH). traffic channels), etc.

12 is a diagram illustrating a method of processing a transmission signal applied to the present disclosure. For example, the transmitted signal may be processed by a signal processing circuit. In this case, the signal processing circuit 1200 may include a scrambler 1210, a modulator 1220, a layer mapper 1230, a precoder 1240, a resource mapper 1250, and a signal generator 1260. At this time, as an example, the operation/function of FIG. 12 may be performed by the processors 202a and 202b and/or the transceivers 206a and 206b of FIG. 2 . Also, as an example, the hardware elements of FIG. 12 may be implemented in the processors 202a and 202b and/or the transceivers 206a and 206b of FIG. 2 . As an example, blocks 1010 to 1060 may be implemented in the processors 202a and 202b of FIG. 2 . Also, blocks 1210 to 1250 may be implemented in the processors 202a and 202b of FIG. 2 , and block 1260 may be implemented in the transceivers 206a and 206b of FIG. 2 , and are not limited to the above-described embodiment.

The codeword may be converted into a radio signal through the signal processing circuit 1200 of FIG. 12 . Here, a codeword is an encoded bit sequence of an information block. Information blocks may include transport blocks (eg, UL-SCH transport blocks, DL-SCH transport blocks). The radio signal may be transmitted through various physical channels (eg, PUSCH, PDSCH) of FIG. 10 . Specifically, the codeword may be converted into a scrambled bit sequence by the scrambler 1210. A scramble sequence used for scrambling is generated based on an initialization value, and the initialization value may include ID information of a wireless device. The scrambled bit sequence may be modulated into a modulation symbol sequence by modulator 1220. The modulation method may include pi/2-binary phase shift keying (pi/2-BPSK), m-phase shift keying (m-PSK), m-quadrature amplitude modulation (m-QAM), and the like.

The complex modulation symbol sequence may be mapped to one or more transport layers by the layer mapper 1230. Modulation symbols of each transport layer may be mapped to corresponding antenna port(s) by the precoder 1240 (precoding). The output z of the precoder 1240 can be obtained by multiplying the output y of the layer mapper 1230 by the N*M precoding matrix W. Here, N is the number of antenna ports and M is the number of transport layers. Here, the precoder 1240 may perform precoding after performing transform precoding (eg, discrete fourier transform (DFT) transform) on the complex modulation symbols. Also, the precoder 1240 may perform precoding without performing transform precoding.

The resource mapper 1250 may map modulation symbols of each antenna port to time-frequency resources. The time-frequency resource may include a plurality of symbols (eg, CP-OFDMA symbols and DFT-s-OFDMA symbols) in the time domain and a plurality of subcarriers in the frequency domain. The signal generator 1260 generates a radio signal from the mapped modulation symbols, and the generated radio signal can be transmitted to other devices through each antenna. To this end, the signal generator 1260 may include an inverse fast fourier transform (IFFT) module, a cyclic prefix (CP) inserter, a digital-to-analog converter (DAC), a frequency uplink converter, and the like. .

The signal processing process for the received signal in the wireless device may be configured in reverse to the signal processing process 1210 to 1260 of FIG. 12 . For example, a wireless device (eg, 200a and 200b of FIG. 2 ) may receive a wireless signal from the outside through an antenna port/transceiver. The received radio signal may be converted into a baseband signal through a signal restorer. To this end, 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 de-mapper process, a postcoding process, a demodulation process, and a de-scramble process. The codeword may be restored to an original information block through decoding. Accordingly, 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.

13 is a diagram illustrating a structure of a radio frame applicable to the present disclosure.

Uplink and downlink transmission based on the NR system may be based on the frame shown in FIG. 13. In this case, one radio frame has a length of 10 ms and may be defined as two 5 ms half-frames (half-frame, HF). One half-frame may be defined as five 1ms subframes (subframes, SFs). One subframe is divided into one or more slots, and the number of slots in a subframe may depend on subcarrier spacing (SCS). In this case, each slot may include 12 or 14 OFDM(A) symbols according to a cyclic prefix (CP). When a normal CP is used, each slot may include 14 symbols. When an extended CP is used, each slot may include 12 symbols. Here, the symbol may include an OFDM symbol (or CP-OFDM symbol) and an SC-FDMA symbol (or DFT-s-OFDM symbol).

Table 1 shows the number of symbols per slot, the number of slots per frame, and the number of slots per subframe according to SCS when a normal CP is used, and Table 2 shows the number of slots according to SCS when an extended CSP is used. Indicates the number of symbols, the number of slots per frame, and the number of slots per subframe.

0 14 10 One One 14 20 2 2 14 40 4 3 14 80 8 4 14 160 16 5 14 320 32

2 12 40 4

In Tables 1 and 2, N ^slot _symb represents the number of symbols in a slot, N ^{frame, μ} _slot represents the number of slots in a frame, and N ^{subframe, μ} _slot represents the number of slots in a subframe. .

In addition, in a system to which the present disclosure is applicable, OFDM(A) numerology (eg, SCS, CP length, etc.) may be set differently among a plurality of cells merged into one UE. Accordingly, (absolute time) intervals of time resources (e.g., SFs, slots, or TTIs) (for convenience, collectively referred to as time units (TUs)) composed of the same number of symbols may be set differently between merged cells.

NR may support multiple numerologies (or subcarrier spacing (SCS)) to support various 5G services. For example, when the SCS is 15 kHz, it supports a wide area in traditional cellular bands, and when the SCS is 30 kHz/60 kHz, dense-urban, lower latency and a wider carrier bandwidth, and when the SCS is 60 kHz or higher, a bandwidth larger than 24.25 GHz can be supported to overcome phase noise.

The NR frequency band is defined as a frequency range of two types (FR1 and FR2). FR1 and FR2 can be configured as shown in the table below. Also, FR2 may mean millimeter wave (mmW).

Frequency range designation Corresponding frequency range Subcarrier Spacing FR1 410MHz - 7125MHz 15, 30, 60 kHz FR2 24250MHz - 52600MHz 60, 120, 240 kHz

Also, as an example, the above-described numerology may be set differently in a communication system to which the present disclosure is applicable. For example, a Terahertz wave (THz) band may be used as a frequency band higher than the aforementioned FR2. In the THz band, the SCS may be set larger than that of the NR system, and the number of slots may be set differently, and is not limited to the above-described embodiment. The THz band will be described below.

14 is a diagram illustrating a slot structure applicable to the present disclosure.

One slot includes a plurality of symbols in the time domain. For example, in the case of a normal CP, one slot includes 7 symbols, but in the case of an extended CP, one slot may include 6 symbols. A carrier includes a plurality of subcarriers in the frequency domain. A resource block (RB) may be defined as a plurality of (eg, 12) consecutive subcarriers in the frequency domain.

In addition, a bandwidth part (BWP) is defined as a plurality of consecutive (P)RBs in the frequency domain, and may correspond to one numerology (eg, SCS, CP length, etc.).

A carrier may include up to N (eg, 5) BWPs. Data communication is performed through an activated BWP, and only one BWP can be activated for one terminal. Each element in the resource grid is referred to as a resource element (RE), and one complex symbol may be mapped.

6G communication system

6G (radio communications) systems are characterized by (i) very high data rates per device, (ii) very large number of connected devices, (iii) global connectivity, (iv) very low latency, (v) battery- It aims to lower 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 four aspects such as "intelligent connectivity", "deep connectivity", "holographic connectivity", and "ubiquitous connectivity", and the 6G system can satisfy the requirements shown in Table 4 below. That is, Table 4 is a table showing the requirements of the 6G system.

Per device peak data rate 1 Tbps E2E latency 1ms Maximum spectral efficiency 100 bps/Hz Mobility support up to 1000 km/hr Satellite integration Fully AI Fully Autonomous vehicles Fully XR Fully Haptic Communication Fully

At this time, the 6G system is enhanced mobile broadband (eMBB), ultra-reliable low latency communications (URLLC), mMTC (massive machine type communications), AI integrated communication, tactile Internet (tactile internet), high throughput, high network capacity, high energy efficiency, low backhaul and access network congestion and improved data security ( can have key factors such as enhanced data security.

15 is a diagram illustrating an example of a communication structure that can be provided in a 6G system applicable to the present disclosure.

Referring to FIG. 15 , a 6G system is expected to have 50 times higher simultaneous wireless communication connectivity than a 5G wireless communication system. URLLC, a key feature of 5G, is expected to become a more mainstream technology by providing end-to-end latency of less than 1 ms in 6G communications. At this time, the 6G system will have much better volume spectral efficiency, unlike the frequently used area spectral efficiency. 6G systems can provide very long battery life and advanced battery technology for energy harvesting, so mobile devices in 6G systems may not need to be charged separately. In addition, new network characteristics in 6G may be as follows.

- Satellites integrated network: 6G is expected to be integrated with satellites to serve the global mobile population. Integration of terrestrial, satellite and public networks into one wireless communications system could be critical for 6G.

- Connected intelligence: Unlike previous generations of wireless communications systems, 6G is revolutionary and will update the wireless evolution from “connected things” to “connected intelligence.” AI can be applied at each step of the communication procedure (or each procedure of signal processing to be described later).

- Seamless integration 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.

- Ubiquitous super 3-dimemtion connectivity: Access to networks and core network capabilities of drones and very low Earth orbit satellites will make super 3-D connectivity in 6G ubiquitous.

In the new network characteristics of 6G as above, some general requirements can be as follows.

- Small cell networks: The idea of small cell networks has been introduced to improve received signal quality resulting in improved throughput, energy efficiency and spectral efficiency in cellular systems. As a result, small cell networks are an essential feature of 5G and Beyond 5G (5GB) and beyond communication systems. Therefore, the 6G communication system also adopts the characteristics of the small cell network.

- Ultra-dense heterogeneous networks: Ultra-dense heterogeneous networks will be another important feature of 6G communication systems. Multi-tier networks composed of heterogeneous networks improve overall QoS and reduce costs.

- High-capacity backhaul: A backhaul connection is characterized by a high-capacity backhaul network to support high-capacity traffic. High-speed fiber and free space optical (FSO) systems may be possible solutions to this problem.

- Radar technology integrated with mobile technology: High-precision localization (or location-based service) through communication is one of the features of 6G wireless communication systems. Thus, radar systems will be integrated with 6G networks.

- Softwarization and virtualization: Softwarization and virtualization are two important features fundamental to the design process in 5GB networks to ensure flexibility, reconfigurability and programmability. In addition, billions of devices can be shared in a shared physical infrastructure.

Core implementation technology of 6G system

- Artificial Intelligence (AI)

The most important and newly introduced technology for the 6G system is AI. AI was not involved in the 4G system. 5G systems will support partial or very limited AI. However, the 6G system will be AI-enabled for full automation. Advances in machine learning will create more intelligent networks for real-time communication in 6G. Introducing AI in communications can simplify and enhance real-time data transmission. AI can use a plethora of analytics to determine how complex target tasks are performed. In other words, AI can increase efficiency and reduce processing delays.

Time-consuming tasks such as handover, network selection, and resource scheduling can be performed instantly by using AI. AI can also play an important role in machine-to-machine, machine-to-human and human-to-machine communications. In addition, AI can be a rapid communication in the brain computer interface (BCI). AI-based communication systems can be supported by metamaterials, intelligent structures, intelligent networks, intelligent devices, intelligent cognitive radios, self-sustaining wireless networks, and machine learning.

Recently, attempts have been made to integrate AI with wireless communication systems, but these are focused on the application layer and network layer, especially deep learning, in wireless resource management and allocation. come. However, such research is gradually developing into the MAC layer and the physical layer, and in particular, attempts to combine deep learning with wireless transmission are appearing in the physical layer. AI-based physical layer transmission means applying a signal processing and communication mechanism based on an AI driver rather than a traditional communication framework in fundamental signal processing and communication mechanisms. For example, deep learning-based channel coding and decoding, deep learning-based signal estimation and detection, deep learning-based multiple input multiple output (MIMO) mechanism, It may include AI-based resource scheduling and allocation.

Machine learning may be used for channel estimation and channel tracking, and may be used for power allocation, interference cancellation, and the like in a downlink (DL) physical layer. Machine learning can also be used for antenna selection, power control, symbol detection, and the like in a MIMO system.

However, the application of DNN for transmission in the physical layer may have the following problems.

AI algorithms based on deep learning require a lot of training data to optimize training parameters. However, due to limitations in acquiring data in a specific channel environment as training data, a lot of training data is used offline. This is because static training on training data in a specific channel environment may cause a contradiction between dynamic characteristics and diversity of a radio channel.

In addition, current deep learning mainly targets real signals. However, the signals of the physical layer of wireless communication are complex signals. In order to match the characteristics of a wireless communication signal, further research is needed on a neural network that detects a complex domain signal.

Hereinafter, machine learning will be described in more detail.

Machine learning refers to a set of actions that train a machine to create a machine that can do tasks that humans can or cannot do. Machine learning requires data and a running model. In machine learning, data learning methods can be largely classified into three types: supervised learning, unsupervised learning, and reinforcement learning.

Neural network training is aimed at minimizing errors in the output. Neural network learning repeatedly inputs training data to the neural network, calculates the output of the neural network for the training data and the error of the target, and backpropagates the error of the neural network from the output layer of the neural network to the input layer in a direction to reduce the error. ) to update the weight of each node in the neural network.

Supervised learning uses training data in which correct answers are labeled in the learning data, and unsupervised learning may not have correct answers labeled in the learning data. That is, for example, learning data in the case of supervised learning related to data classification may be data in which each learning data is labeled with a category. Labeled training data is input to the neural network, and an error may be calculated by comparing the output (category) of the neural network and the label of the training data. The calculated error is back-propagated in a reverse direction (ie, from the output layer to the input layer) in the neural network, and the connection weight of each node of each layer of the neural network may be updated according to the back-propagation. The amount of change in the connection weight of each updated node may be determined according to a learning rate. The neural network's computation of input data and backpropagation of errors can constitute a learning cycle (epoch). The learning rate may be applied differently according to the number of iterations of the learning cycle of the neural network. For example, a high learning rate is used in the early stages of neural network learning to increase efficiency by allowing the neural network to quickly achieve a certain level of performance, and a low learning rate can be used in the late stage to increase accuracy.

The learning method may vary depending on the characteristics of the data. For example, in a case where the purpose of the receiver is to accurately predict data transmitted by the transmitter in a communication system, it is preferable to perform learning using supervised learning rather than unsupervised learning or reinforcement learning.

The learning model corresponds to the human brain, and the most basic linear model can be considered. ) is called

The neural network cord used as a learning method is largely divided into deep neural networks (DNN), convolutional deep neural networks (CNN), and recurrent boltzmann machine (RNN). and this learning model can be applied.

Terahertz (THz) communication

THz communication can be applied in 6G systems. For example, the data transmission rate can be increased by increasing the bandwidth. This can be done using sub-THz communication with wide bandwidth and applying advanced massive MIMO technology.

16 is a diagram showing an electromagnetic spectrum applicable to the present disclosure. As an example, referring to FIG. 16 , THz waves, also known as sub-millimeter radiation, generally represent a frequency band between 0.1 THz and 10 THz with corresponding wavelengths in the range of 0.03 mm-3 mm. The 100 GHz-300 GHz band range (sub THz band) is considered a major part of the THz band for cellular communications. Adding to the sub-THz band mmWave band will increase 6G cellular communications capacity. Among the defined THz bands, 300 GHz-3 THz is in the far infrared (IR) frequency band. The 300 GHz-3 THz band is part of the broad band, but is at the border of the wide band, just behind the RF band. Thus, this 300 GHz-3 THz band exhibits similarities to RF.

The main characteristics of THz communications include (i) widely available bandwidth to support very high data rates, and (ii) high path loss at high frequencies (highly directional antennas are indispensable). The narrow beamwidth produced by the highly directional antenna reduces interference. The small wavelength of the THz signal allows a much larger number of antenna elements to be incorporated into devices and BSs operating in this band. This enables advanced adaptive array technology to overcome range limitations.

optical wireless technology

Optical wireless communication (OWC) technology is envisioned for 6G communications in addition to RF-based communications for all possible device-to-access networks. These networks access network-to-backhaul/fronthaul network connections. OWC technology is already in use after the 4G communication system, but will be more widely used to meet the needs of the 6G communication system. OWC technologies such as light fidelity, visible light communication, optical camera communication, and free space optical (FSO) communication based on a wide band are already well-known technologies. Communications based on optical wireless technology can provide very high data rates, low latency and secure communications. Light detection and ranging (LiDAR) can also be used for super-resolution 3D mapping in 6G communications based on broadband.

FSO backhaul network

The transmitter and receiver characteristics of an FSO system are similar to those of a fiber optic network. Thus, data transmission in FSO systems is similar to fiber optic systems. Therefore, FSO can be a good technology to provide backhaul connectivity in 6G systems along with fiber optic networks. With FSO, very long-distance communication is possible even at a distance of 10,000 km or more. FSO supports high-capacity backhaul connectivity for remote and non-remote locations such as ocean, space, underwater and isolated islands. FSO also supports cellular base station connectivity.

Massive MIMO technology

One of the key technologies to improve spectral efficiency is to apply MIMO technology. As MIMO technology improves, so does the spectral efficiency. Therefore, massive MIMO technology will be important in 6G systems. Since MIMO technology uses multiple paths, multiplexing technology and beam generation and operation technology suitable for the THz band must be considered as important so that data signals can be transmitted through more than one path.

block chain

Blockchain will be an important technology for managing large amounts of data in future communication systems. Blockchain is a form of distributed ledger technology, where a distributed ledger is a database that is distributed across numerous nodes or computing devices. Each node replicates and stores an identical copy of the ledger. Blockchain is managed as a peer to peer (P2P) network. It can exist without being managed by a centralized authority or server. Data on a blockchain is collected together and organized into blocks. Blocks are linked together and protected using cryptography. Blockchain is the perfect complement to the IoT at scale with inherently improved interoperability, security, privacy, reliability and scalability. Thus, blockchain technology provides multiple capabilities such as interoperability between devices, traceability of large amounts of data, autonomous interaction of other IoT systems, and large-scale connection reliability in 6G communication systems.

3D Networking

The 6G system integrates terrestrial and air networks to support vertical expansion of user communications. 3D BS will be provided via low-orbit satellites and UAVs. Adding a new dimension in terms of height and related degrees of freedom makes 3D connections quite different from traditional 2D networks.

quantum communication

In the context of 6G networks, unsupervised reinforcement learning of networks is promising. Supervised learning approaches cannot label the vast amount of data generated by 6G. Labeling is not required in unsupervised learning. Thus, this technique can be used to autonomously build representations of complex networks. Combining reinforcement learning and unsupervised learning allows networks to operate in a truly autonomous way.

drone

Unmanned aerial vehicles (UAVs) or drones will be an important element in 6G wireless communications. In most cases, high-speed data wireless connectivity is provided using UAV technology. Base station entities are installed on UAVs to provide cellular connectivity. UAVs have certain features not found in fixed base station infrastructure, such as easy deployment, strong line-of-sight links, and degrees of freedom with controlled mobility. During emergencies, such as natural disasters, the deployment of terrestrial communications infrastructure is not economically feasible and cannot provide services in sometimes volatile environments. UAVs can easily handle this situation. UAVs will become a new paradigm in the field of wireless communication. This technology facilitates three basic requirements of a wireless network: eMBB, URLLC and mMTC. UAVs can also support multiple purposes, such as enhancing network connectivity, fire detection, disaster emergency services, security and surveillance, pollution monitoring, parking monitoring, accident monitoring, and more. Therefore, UAV technology is recognized as one of the most important technologies for 6G communication.

Cell-free Communication

The tight integration of multiple frequencies and heterogeneous communication technologies is critical for 6G systems. As a result, users can seamlessly move from one network to another without having to make any manual configuration on the device. The best network is automatically selected from available communication technologies. This will break the limitations of the cell concept in wireless communication. Currently, user movement from one cell to another causes too many handovers in high-density networks, resulting in handover failures, handover delays, data loss and ping-pong effects. 6G cell-free communication will overcome all of this and provide better QoS. Cell-free communication will be achieved through multi-connectivity and multi-tier hybrid technologies and different heterogeneous radios of devices.

Integration of wireless information and energy transfer (WIET)

WIET uses the same fields and waves as wireless communication systems. In particular, sensors and smartphones will be charged using wireless power transfer during communication. WIET is a promising technology for extending the lifetime of battery charging wireless systems. Thus, battery-less devices will be supported in 6G communications.

Integration of sensing and communication

Autonomous radio networks are capable of continuously sensing dynamically changing environmental conditions and exchanging information between different nodes. In 6G, sensing will be tightly integrated with communications to support autonomous systems.

Integration of access backhaul networks

In 6G, the density of access networks will be enormous. Each access network is connected by fiber and backhaul connections such as FSO networks. To cope with the very large number of access networks, there will be tight integration between access and backhaul networks.

Holographic Beamforming

Beamforming is a signal processing procedure that adjusts an antenna array to transmit radio signals in a specific direction. A subset of smart antennas or advanced antenna systems. Beamforming technology has several advantages such as high signal-to-noise ratio, interference avoidance and rejection, and high network efficiency. Hologram beamforming (HBF) is a new beamforming method that differs significantly from MIMO systems because it uses software-defined antennas. HBF will be a very effective approach for efficient and flexible transmission and reception of signals in multi-antenna communication devices in 6G.

big data analytics

Big data analysis is a complex process for analyzing various large data sets or big data. This process ensures complete data management by finding information such as hidden data, unknown correlations and customer preferences. Big data is collected from various sources such as videos, social networks, images and sensors. This technology is widely used to process massive data in 6G systems.

large intelligent surface (LIS)

In the case of THz band signals, there may be many shadow areas due to obstructions due to strong linearity. By installing LIS near these shadow areas, LIS technology that expands the communication area, strengthens communication stability, and provides additional additional services becomes important. An LIS is an artificial surface made of electromagnetic materials and can change the propagation of incoming and outgoing radio waves. LIS can be seen as an extension of Massive MIMO, but has a different array structure and operating mechanism from Massive MIMO. In addition, the LIS is low in that it operates as a reconfigurable reflector with passive elements, i.e. it only passively reflects signals without using an active RF chain. It has the advantage of having low power consumption. In addition, since each passive reflector of the LIS must independently adjust the phase shift of an incident signal, it may be advantageous for a wireless communication channel. By properly adjusting the phase shift through the LIS controller, the reflected signal can be collected at the target receiver to boost the received signal power.

Terahertz (THz) wireless communication

17 is a diagram illustrating a THz communication method applicable to the present disclosure.

Referring to FIG. 17, THz wireless communication uses wireless communication using THz waves having a frequency of approximately 0.1 to 10 THz (1 THz = 1012 Hz), and a terahertz (THz) band radio using a very high carrier frequency of 100 GHz or more. can mean communication. THz waves are located between RF (Radio Frequency)/millimeter (mm) and infrared bands, and (i) transmit non-metal/non-polarizable materials better than visible light/infrared rays, and have a shorter wavelength than RF/millimeter waves and have high straightness. Beam focusing may be possible.

In addition, since the photon energy of the THz wave is only a few meV, it is harmless to the human body. A frequency band expected to be used for THz wireless communication may be a D-band (110 GHz to 170 GHz) or H-band (220 GHz to 325 GHz) band with low propagation loss due to molecular absorption in the air. Standardization discussions on THz wireless communication are being discussed centering on the IEEE 802.15 THz working group (WG) in addition to 3GPP, and standard documents issued by the IEEE 802.15 TG (task group) (e.g., TG3d, TG3e) are described in this specification. It can be specified or supplemented. THz wireless communication may be applied to wireless cognition, sensing, imaging, wireless communication, THz navigation, and the like.

Specifically, referring to FIG. 17 , a THz wireless communication scenario can be classified into a macro network, a micro network, and a nanoscale network. In macro networks, THz wireless communication can be applied to V2V (vehicle-to-vehicle) connections and backhaul/fronthaul connections. In micro networks, THz wireless communication is applied to indoor small cells, fixed point-to-point or multi-point connections such as wireless connections in data centers, and near-field communication such as kiosk downloading. It can be. Table 5 below is a table showing an example of a technique that can be used in THz waves.

Transceivers Device Available immature: UTC-PD, RTD and SBD Modulation and coding Low order modulation techniques (OOK, QPSK), LDPC, Reed Soloman, Hamming, Polar, Turbo Antenna Omni and Directional, phased array with low number of antenna elements Bandwidth 69 GHz (or 23 GHz) at 300 GHz Channel models Partially Data rate 100 Gbps outdoor deployment No Fee space loss High Coverage Low Radio Measurements 300 GHz inddor Device size Few micrometers

18 is a diagram illustrating a THz wireless communication transceiver applicable to the present disclosure.

Referring to FIG. 18, THz wireless communication can be classified based on a method for generating and receiving THz. The THz generation method can be classified as an optical device or an electronic device based technology.

At this time, the method of generating THz using an electronic device is a method using a semiconductor device such as a resonant tunneling diode (RTD), a method using a local oscillator and a multiplier, a method using a compound semiconductor HEMT (high electron mobility transistor) based There are a monolithic microwave integrated circuits (MMIC) method using an integrated circuit, a method using an integrated circuit based on Si-CMOS, and the like. In the case of FIG. 18, a doubler, tripler, or multiplier is applied to increase the frequency, and the radiation is emitted by the antenna after passing through the subharmonic mixer. Since the THz band forms high frequencies, a multiplier is essential. Here, the multiplier is a circuit that makes the output frequency N times greater than the input, matches the desired harmonic frequency, and filters out all other frequencies. In addition, beamforming may be implemented by applying an array antenna or the like to the antenna of FIG. 18 . In FIG. 18, IF denotes an intermediate frequency, a tripler and a multiplier denote a multiplier, PA denotes a power amplifier, and LNA denotes a low noise amplifier. ), PLL represents a phase-locked loop.

19 is a diagram illustrating a THz signal generation method applicable to the present disclosure. 20 is a diagram illustrating a wireless communication transceiver applicable to the present disclosure.

Referring to FIGS. 19 and 20 , the optical device-based THz wireless communication technology refers to a method of generating and modulating a THz signal using an optical device. An optical element-based THz signal generation technology is a technology that generates an ultra-high speed optical signal using a laser and an optical modulator and converts it into a THz signal using an ultra-high speed photodetector. Compared to a technique using only an electronic device, this technique can easily increase the frequency, generate a high-power signal, and obtain a flat response characteristic in a wide frequency band. As shown in FIG. 19, a laser diode, a broadband light modulator, and a high-speed photodetector are required to generate a THz signal based on an optical device. In the case of FIG. 19 , a THz signal corresponding to a wavelength difference between the lasers is generated by multiplexing light signals of two lasers having different wavelengths. In FIG. 19, an optical coupler refers to a semiconductor device that transmits an electrical signal using light waves in order to provide electrical isolation and coupling between circuits or systems, and UTC-PD (uni-travelling carrier photo- The detector is one of the photodetectors, and is a device that uses electrons as active carriers and reduces the movement time of electrons through bandgap grading. UTC-PD is capable of photodetection above 150 GHz. In FIG. 20, an erbium-doped fiber amplifier (EDFA) represents an optical fiber amplifier to which erbium is added, a photo detector (PD) represents a semiconductor device capable of converting an optical signal into an electrical signal, and an OSA represents various optical communication functions (e.g. , photoelectric conversion, electrical optical conversion, etc.) represents an optical module (optical sub assembly) that is modularized into one component, and DSO represents a digital storage oscilloscope.

21 is a diagram illustrating a transmitter structure applicable to the present disclosure. 22 is a diagram showing a modulator structure applicable to the present disclosure.

Referring to FIGS. 21 and 22 , in general, a phase of a signal may be changed by passing an optical source of a laser through an optical wave guide. At this time, data is loaded by changing electrical characteristics through a microwave contact or the like. Thus, the optical modulator output is formed into a modulated waveform. A photoelectric modulator (O/E converter) is an optical rectification operation by a nonlinear crystal, an O/E conversion by a photoconductive antenna, and a bundle of electrons in light flux. THz pulses can be generated according to emission from relativistic electrons, etc. A THz pulse generated in the above manner may have a unit length of femto second to pico second. An O/E converter uses non-linearity of a device to perform down conversion.

Considering the THz spectrum usage, it is necessary to use several contiguous GHz bands for fixed or mobile service for terahertz systems. more likely to use According to outdoor scenario criteria, available bandwidth may be classified based on oxygen attenuation of 10^2 dB/km in a spectrum up to 1 THz. Accordingly, a framework in which the available bandwidth is composed of several band chunks may be considered. As an example of the framework, if the length of a THz pulse for one carrier is set to 50 ps, the bandwidth (BW) becomes about 20 GHz.

Effective down conversion from the infrared band to the THz band depends on how to utilize the nonlinearity of the O/E converter. That is, in order to down-convert to the desired terahertz band (THz band), the photoelectric converter (O / E converter) having the most ideal non-linearity to move to the corresponding terahertz band (THz band) design is required. If an O/E converter that does not fit the target frequency band is used, there is a high possibility that an error will occur with respect to the amplitude and phase of the corresponding pulse.

A terahertz transmission/reception system may be implemented using one photoelectric converter in a single carrier system. Depending on the channel environment, as many photoelectric converters as the number of carriers may be required in a multi-carrier system. In particular, in the case of a multi-carrier system using several broadbands according to a plan related to the above-mentioned spectrum use, the phenomenon will be conspicuous. In this regard, a frame structure for the multi-carrier system may be considered. A signal down-frequency converted based on the photoelectric converter may be transmitted in a specific resource region (eg, a specific frame). The frequency domain of the specific resource domain may include a plurality of chunks. Each chunk may consist of at least one component carrier (CC).

In order to realize ultra-high-speed communication services using ultra-wideband frequency bands in the terahertz (THz) band, ultra-high sampling rates for DAC (Digital to Analog Converter) and ADC (Analog to Digital Converter) may be required. . In addition, since the terahertz band has extreme path loss due to its characteristics, it is common to use ultra-massive MIMO technology to overcome this problem. Through high beam gain using a large number of antennas, to overcome path loss. However, a very large number of DACs/ADCs may be required to obtain a high beam gain, which may cause very high power consumption. For this reason, a method of using a low resolution DAC/ADC, particularly a 1-bit DAC/ADC, for terahertz band communication is being actively discussed.

In the case of the conventional spatial modulation scheme based on antenna selection and spatial modulation based on dedicated phase rotation, signal transmission and reception based on multiple transmit antennas may be possible by using only some of a plurality of transmit antennas. However, the conventional method is not suitable in terms of securing the distance between antennas, beam weights, or configuring antennas in MIMO precoders, which can be a problem in MIMO precoding or beamforming. .

In order to solve the above problems, the present disclosure intends to propose a multi-antenna based transmission/reception technology based on DAC/ADC.

Prior to describing the present disclosure in detail, in the present disclosure, a transmitter and a receiver may be devices of a wireless communication system including a terminal and a base station, and are not limited to specific devices or entities. In addition, the transmitter may be included in the transmitting end, and the receiver may be included in the receiving end, and when the transmitter is capable of not only transmitting data but also receiving data, the receiver may be included, and similarly, the receiving end may also include the transmitter.

Meanwhile, the present disclosure may be based on a single carrier system based on low resolution DAC/ADC. In the following description, a specific embodiment of the present disclosure will be described based on a single carrier system, but is not limited thereto.

In addition, in describing an embodiment of the present disclosure, it is assumed that a channel within a symbol interval can experience a block fading channel that does not change when a terminal and a base station transmit and receive signals.

In addition, in describing an embodiment of the present disclosure, it is described based on a phase shift keying (PSK) method. However, this is for clarity of explanation and the present disclosure is not limited thereto.

Also, in describing the embodiments of the present disclosure, the phase definition antenna subset and the phase definition antenna set may be used interchangeably.

Hereinafter, specific embodiments of the present disclosure will be described in detail with reference to the drawings.

Specific embodiments of the present disclosure

23 is a block diagram of a transmitter applicable to the present disclosure.

) 및 이를 지원하는 안테나 수(

) 및 구성에 따라 특정 시간에 다수 개의 안테나(2308, 2309, 2310) 중 일부 안테나만을 이용하여 전송될 수 있다. 이 경우 스위칭 모듈(2307)을 통해 다수 개의 안테나 중 한 안테나가 선택될 수 있다. For the total modulation level (M) and bits, the effective modulation level of the symbol transmitted over the actual physical channel (

) and the number of antennas supporting it (

) and configuration, it may be transmitted using only some of the plurality of antennas 2308, 2309, and 2310 at a specific time. In this case, one antenna among a plurality of antennas may be selected through the switching module 2307.

Meanwhile, an input bit stream 2303 for phase-defining antenna-based modulation may be an output that has undergone channel encoding and interleaving for information bits, and additionally scrambling if necessary. It may be an output that has gone through (scrambling).

)와 성상도 위상 회전 인덱스를 포함하는 비트(

)로 구성될 수 있다.In the phase-defined antenna-based modulation method, the input bit stream 2303 consists of the number of bits (eg, k bits) corresponding to the total modulation level (M), which is the effective transmission bits constituting the actual transmission symbol (

) and bits containing the constellation phase rotation index (

) can be configured.

) 중 유효 전송 비트 (

)(2301)는 변조기 (modulator)에 의해 변조(e.g.

)(2304)될 수 있으며, RF부(2306)에서 신호 처리가 수행될 수 있다. 또한,

비트를 통해 성상도 위상 회전 지시자 (constellation phase indicator)(2302)가 구성될 수 있다. Therefore, in the phase-defined antenna-based modulation scheme, the input bit stream 2303 (

) of the effective transmission bits (

) 2301 is modulated by a modulator (eg

) 2304, and signal processing may be performed in the RF unit 2306. also,

A constellation phase indicator 2302 may be configured through bits.

전송 비트에 대하여,

일 수 있다. 이 때,

은 송신단에서 고려할 수 있는 최대 변조 레벨에 대하여 결정될 수 있으며, 안테나 구성은 1-D 혹은 2-D 방식을 고려할 수 있다. 안테나 구성 방식에 대하여는 하기에서 다른 도면을 참조하여 더욱 상세하게 설명할 것이다.Looking in detail, the number of antennas with different transmission constellation rotation values is

Regarding the transmission bit,

can be At this time,

can be determined for the maximum modulation level that can be considered by the transmitting end, and the antenna configuration can consider a 1-D or 2-D scheme. The antenna configuration method will be described in more detail with reference to other drawings below.

24 is a diagram illustrating an antenna configuration applicable to the present disclosure. More specifically, it is a diagram showing an antenna configuration example for applying a beamforming technique using a phase-defining antenna-based modulation technique supporting a 16-PSK scheme.

), 수직(

) 영역 각각에 대하여 λ/2일 수 있다. As an embodiment, since each antenna can be based on the QPSK scheme, the QPSK scheme can be implemented with one antenna and the 8-PSK scheme can be implemented with two antennas. A 16-PSK scheme can be implemented with four antennas. The spacing between antennas having the same phase rotation value, that is, the spacing between phase-defining antenna groups (subsets) is generally horizontal (

), Perpendicular(

) may be λ/2 for each region.

In general, when configuring a multi-antenna (massive MIMO), a single panel-based multi-antenna configuration method and a multi-panel-based multi-antenna configuration method may be considered. 24 is a diagram showing only one panel. The single-panel-based multi-antenna configuration method is further detailed with reference to FIGS. 25 to 28 and the multi-panel-based multiple-antenna configuration method to FIGS. 29 to 32 below. will explain

25 to 28 are diagrams illustrating single-panel-based multi-antenna configurations applicable to the present disclosure. More specifically, FIG. 25 is an example of a single polarized antenna planar array structure composed of 1-D phase-defining antenna subsets based on the 16-PSK scheme. 26 is an example of a cross-polarized antenna planar array composed of 1-D phase-defining antenna subsets based on the 8-PSK scheme, and FIG. 27 is an example of a 1-D phase-defining antenna subset based on the 16-PSK scheme. An example for a cross-polarized antenna planar array. 28 shows a single polarized antenna planar array structure composed of 2-D phase-defining antenna subsets based on 16-PSK.

), 수직(

) 영역 각각에 대하여 λ/2(반파장)일 수 있다. 한편, 도 25와 같이 단일 편파 안테나 평면 어레이 구조에 비해, 도 26 내지 도 27과 같이 교차 편파 안테나 평면으로 구성 시 동일 면적인 평면 내 더 많은 안테나를 배치할 수 있다.As an embodiment, in the case of a single panel-based antenna configuration, the antenna may be configured in a 1-D uniform array or 2-D uniform array method. The spacing between antenna groups is generally horizontal for efficient beamforming (

), Perpendicular(

) may be λ/2 (half-wavelength) for each region. On the other hand, compared to a single polarized antenna planar array structure as shown in FIG. 25, more antennas can be arranged in a plane with the same area when configured as a cross-polarized antenna plane as shown in FIGS. 26 to 27.

As an embodiment, a constellation corresponding to each number is mapped and transmitted to each antenna, and each constellation may have a rotation value of a different constellation axis. The black antenna in the drawing may mean an antenna that is active at the current moment and used for transmission, and the white antenna is included in the phase definition antenna set, but is inactive at the current moment and means an antenna that is not used for transmission or does not transmit a valid signal. can do. An activated antenna may vary according to time.

29 to 32 are diagrams illustrating multi-panel-based multi-antenna configurations applicable to the present disclosure. More specifically, FIG. 29 is an embodiment of a single polarized antenna planar array structure composed of 1-D phase-defining antenna subsets using a 1-D panel, and FIG. 30 similarly uses a 1-D panel, -D This is an embodiment of a cross-polarized antenna planar array structure composed of a subset of phase-defining antennas. 31 is an embodiment of a single polarized antenna planar array structure composed of 1-D phase-defining antenna subsets using a 2-D panel. 32 is an embodiment of a cross-polarized antenna planar array structure composed of a subset of 1-D phase-defining antennas using a 2-D panel.

Although a high-gain antenna is required for THz band communication, the use of a horn antenna or patch antenna type antenna is widely known for design reasons of an antenna array configuration. Since it is difficult to reduce the distance between antenna elements to within λ/2 for efficient beamforming, antennas having different constellation axes cannot be added while maintaining the effective distance between antenna elements at λ/2. This problem can be solved by constructing a multi-panel antenna and having different constellation axes for each panel.

In the following description, it is assumed that it is based on a multi-panel-based multi-transmission antenna configuration, but this is only for clarity of explanation and the present disclosure is not limited thereto.

33 is a diagram illustrating a multi-panel configuration for a phase-defined antenna-based modulation scheme applicable to the present disclosure.

와 같은 위상 차이가 발생할 수 있다. 이를 원거리 장 (far-field)에 대한 평면파 (plane wave) 관점에서 모델링하면, 도 34와 같을 수 있다.As an embodiment, each of the multi-panels 3301, 3302, 3303, and 3304 includes a plurality of phase definition antennas, and each panel may be based on a phase rotation value of a different constellation axis. Each phase-defining antenna may be horizontally and vertically spaced apart by λ/2. A very narrow beam is formed for each panel unit, and a transmission symbol can be transmitted based on the constellation of each panel. In this case, each beam based on the transmission constellation for each panel

A phase difference such as may occur. If this is modeled in terms of a plane wave for a far-field, it may be as shown in FIG. 34 .

34 is a diagram showing plane waves of multiple panels applicable to the present disclosure.

As an embodiment, A (3401) and B (3402) may respectively represent antenna groups having different constellation axes as transmitter antenna groups. C 3403 may represent a receiving end. A and B may each perform beamforming toward C, which is a receiving end. Different antenna groups A (3401) and B (3402) may appear as different panels. Here, it is assumed that A and B have a uniform linear array structure, and that the spacing between different groups is equal to or larger than a half wavelength so as not to affect efficient beamforming.

).또한, 서로 인접한 안테나 그룹과는

만큼의 위상 차이가 발생할 수 있다. 한편, 변조 레벨 증가에 따라 요구되는 패널 수가 증가할수록, 기준 안테나 그룹에서 이격된 안테나 그룹에 대한 위상 차이는 더욱 커지게 된다. 빔 송신 시 이러한 위상 차이를 고려하지 않으면, 특정 대상에 대한 빔포밍이 비효율적이고 부정확해질 수 있는 바, 적절한 처리가 필요할 수 있다.At this time, AoD (Angle of Departure) may be the same because a plane wave is assumed (

). In addition, the antenna groups adjacent to each other

As much phase difference may occur. Meanwhile, as the number of panels required increases with the increase in the modulation level, the phase difference between the antenna groups spaced apart from the reference antenna group becomes larger. If the phase difference is not considered during beam transmission, beamforming for a specific target may become inefficient and inaccurate, and appropriate processing may be required.

35 is a diagram illustrating a symbol configuration applicable to the present disclosure. In this case, the symbol may correspond to the symbol of FIG. 14, and the symbol period 3500 may be sufficiently smaller than the channel coherence time.

As an embodiment, the symbol structure may largely include a pilot symbol period 3501 and a data symbol period 3502.

The data symbol period 3502 may be used for actual information transmission, may be a period in which an effective transmission symbol is transmitted, and may be generated based on a data signal. That is, the data signal and the pilot signal may be generated as data symbols and pilot symbols, respectively, during modulation.

Meanwhile, the pilot symbol interval 3501 may be mainly used for purposes such as channel estimation and synchronization. In this case, channel estimation is a process performed for smooth communication between transmitting and receiving ends, and may include a process of estimating channel state information (CSI) based on a pilot symbol. For example, since the direction of a beam transmitted by a transmitting end may have to be changed depending on the location, altitude, or condition of a receiving end, channel state information (CSI) includes information for the transmitting end or the receiving end to determine an appropriate beam direction. may be included. When transmitting a beam, the transmitter may determine the direction of the beam based on channel state information estimated by the receiver. Alternatively, the receiving end may directly determine the optimal beam direction based on the estimated channel state information and transmit the channel state information on the beam direction to the transmitting end.

In addition, information on the degree of deformation such as attenuation, diffraction, and reflection of the signal between the transmitting and receiving end, channel such as rank, precoding vector and / or matrix, and signal-to-noise ratio (SINR) Quality and signal quality may be included in the channel state information.

Meanwhile, when a transmitting end transmits a pilot symbol, which is a basis for estimating channel state information, to a receiving end, the pilot symbol may be transmitted based on a single constellation or the pilot symbol may be transmitted based on multiple constellations.

As an embodiment, when a pilot symbol is transmitted based on a single constellation, the transmitter may transmit the pilot symbol using only constellation points included in one reference constellation axis. In this case, the reference constellation is one of the constellation rotation sets held by the transmitting end, and the reference constellation (ie, the reference constellation axis phase rotation value) may be known to the transmitting end and the receiving end or inferred by a value notified by the sending end. . As an example, a QPSK constellation (that is, a pure QPSK constellation without constellation axis rotation) may be a reference constellation.

) 이내에서 송신단이 보유한 성상도 셋 (

)에 대한 파일럿 심볼이 적어도 한번 이상 전송되도록 할 수 있다. 이에 대하여는, 도 36을 참조하여 더욱 상세하게 설명할 것이다.As another embodiment, when transmitting a pilot symbol based on multi-constellation, the transmitting end uses channel coherent time (channel coherent time,

), three constellations possessed by the transmitter within (

) may be transmitted at least once. This will be described in more detail with reference to FIG. 36 .

= 4인 일 실시예를 설명하기 위한 도면이다.36 is a diagram illustrating a pilot symbol transmission method according to an embodiment of the present disclosure. More specifically, in the case of transmitting pilot symbols based on multiple constellations, the number of panels is four, that is, a rotated version of the constellation held by the transmitting end (or all modulation symbols) within the channel coherent time. The subset of antennas required to represent and transmit, i.e., the number of panels) is four, that is,

= 4 is a diagram for explaining an embodiment.

}에 관련될 수 있으며, Ant 1은 {

}에 관련될 수 있다. Ant 2는 {

}에 관련될 수 있으며, Ant 3은 {

}에 관련될 수 있다.The antenna subsets may be divided into Ant 0, Ant 1, Ant 2, and Ant 3, respectively. Antenna subset Ant 0 is {0,

}, and Ant 1 is {

}. Ant 2 is {

}, and Ant 3 uses {

}.

) 이내에서 송신단이 보유한 성상도 셋 (

)에 대한 파일럿 심볼이 적어도 한번 이상 전송되도록 할 수 있다. 즉, 예를 들어 성상도 패널이 총 네 개이면,

이내에 4n (n: 양의 정수 (positive integer))의 파일럿 심볼 전송 기회를 갖도록 할 수 있다. 즉, 다중 패널로 구성되는 각 안테나 서브셋에 대하여, 적어도 한번 이상 파일럿 심볼을 전송할 기회를 갖게 할 수 있다.In this case, as an embodiment, when transmitting pilot symbols based on multi-constellation, the transmitting end uses channel coherent time (channel coherent time,

), three constellations possessed by the transmitter within (

) may be transmitted at least once. That is, for example, if there are four constellation panels in total,

It is possible to have 4n (n: positive integer) pilot symbol transmission opportunities within the range. That is, for each antenna subset composed of multiple panels, an opportunity to transmit a pilot symbol may be provided at least once.

In addition, when pilot symbols are transmitted based on multi-constellation, according to another embodiment, first, the n value is adjusted based on the estimation result reported by the receiving end for pilot symbols transmitted based on multi-constellation, symbols can be transmitted.

) 이내에서 송신단이 보유한 성상도 셋(

)에 대하여 전체 혹은 일부의 성상도에 대한 안테나 서브셋에서 파일럿 심볼을 전송할 수 있다. 즉, 송신단이 송신하는 파일럿 심볼은 일부 성상도만을 기반으로 할 수 있다. 또한, 송신단이 송신하는 파일럿 심볼은 기준 성상도(예를 들어,

변조 심볼에 대한 회전 없는 성상도) 점을 기반으로 할 수 있으며, 이를 기준으로 N (≤2인 정수) 안테나 서브셋 그룹 (안테나 패널) 간격으로 떨어진 안테나 서브셋 그룹들을 통해서만 파일럿 심볼을 전송할 수 있다. 예를 들어, N=1이면, 안테나 서브셋 그룹 0 (혹은 안테나 패널 0), 안테나 서브셋 그룹 2 (혹은 안테나 패널 2), … 을 통해서 해당되는 성상도 점에 대한 파일럿 심볼을 전송할 수 있다.As another embodiment, when transmitting pilot symbols based on multi-constellation, the transmitting end uses channel coherent time (channel coherent time,

) within three constellations possessed by the transmitter (

), pilot symbols may be transmitted in an antenna subset for all or part of the constellation. That is, pilot symbols transmitted by the transmitter may be based on only some constellations. In addition, a pilot symbol transmitted by a transmitter is a reference constellation (eg,

Constellation without rotation of the modulation symbol) point, and based on this, pilot symbols can be transmitted only through antenna subset groups spaced apart at N (integer ≤ 2) antenna subset groups (antenna panel) intervals. For example, if N=1, antenna subset group 0 (or antenna panel 0), antenna subset group 2 (or antenna panel 2), ... A pilot symbol for a corresponding constellation point can be transmitted through

이내에 적어도 한번 이상 전송될 수 있다. 즉, 파일럿 심볼의 전송 기회는

이내에 파일럿 심볼 전송을 위한 성상도 패널 수 * n (n은 양의 정수 (positive integer))일 수 있다.In this case, the pilot symbol based on some constellation is

It can be transmitted at least once within That is, the transmission opportunity of the pilot symbol is

The number of constellation panels for pilot symbol transmission within * n (n is a positive integer).

Meanwhile, the method of transmitting a pilot symbol based on a single constellation described above may be mixed with a method of transmitting a pilot symbol based on multiple constellations. For example, the single-antenna transmission method can be used when it is determined that the channel conditions between a specific antenna subset for transmitting pilot symbols and the receiving end are almost similar or can be inferred from other antenna subsets and the receiving end. there is. Therefore, the transmitting end first transmits a pilot symbol based on the multi-constellation diagram, identifies the correlation between each antenna subset (or antenna panel) and the channel state of the receiving end, and determines that the channel conditions of the transmitting and receiving end are similar to each other or determines If it is determined that it can be inferred because it is constant and fixed, a pilot symbol can be transmitted based on a single constellation.

As an embodiment, the transmitting end may dynamically select and transmit whether pilot symbols are based on multi-constellation or single constellations according to channel similarity when transmitting pilot symbols. Accordingly, it is possible to transmit information on the currently transmitted signal based on which constellation to the receiving end.

37 is a diagram illustrating an operating method of a receiving end according to an embodiment of the present disclosure. As mentioned above, the receiving end and the transmitting end mentioned below may be devices or entities including a terminal or a base station.

The receiving end may receive the pilot symbol from the transmitting end (S3701). The receiving end may estimate channel state information using the pilot symbol received from the transmitting end (S3702). Channel state information includes information on the degree of deformation such as optimal beam direction, attenuation, diffraction, and reflection of the signal between the transmitting and receiving end, rank, precoding vector and / or matrix, signal-to-noise ratio Channel quality and signal quality such as (SINR) may be included. Meanwhile, the received pilot symbol may be transmitted based on a single constellation or based on multiple constellations, which may be as described above.

)이 4인 경우, 2개의 안테나 서브셋, 혹은 안테나 패널을 통해 위상 정의 안테나 기반 변조 방식을 통해 통신이 가능할 수 있다. 이에 따라, 수신한 파일럿 심볼은 다른 성상도 위상 회전 값을 가지고 있을 수 있음에도 불구하고, 수신단은 현재 수신한 파일럿 심볼을 QPSK 성상도에 대한 신호로 가정(혹은 치환)하여 채널 상태 정보를 추정할 수 있다. 즉, 추정된 채널 상태 정보에는 위상 회전에 대한 영향이 고려되지 않도록 할 수 있다. 다만, 단일 성상도에 대한 축 위상값을 명백히 알 수 있는 경우, 이에 대한 가정을 하지 않을 수 있다. As an embodiment, when channel state information is estimated using a pilot symbol transmitted based on a single constellation, the receiving end may estimate channel state information considering that constellation rotation is not applied to the received pilot symbol. there is. As an example, the total modulation level is 8 (M = 8), and the effective modulation level (

) is 4, communication may be possible through a phase-defined antenna-based modulation scheme through two antenna subsets or antenna panels. Accordingly, although the received pilot symbol may have a different constellation phase rotation value, the receiving end can estimate channel state information by assuming (or replacing) the currently received pilot symbol as a signal for the QPSK constellation. there is. That is, the effect of the phase rotation may not be considered in the estimated channel state information. However, if the axis phase value for a single constellation is clearly known, this assumption may not be made.

Meanwhile, when the receiving end receives the pilot symbol based on a single constellation, the single constellation may be indicated by the transmitting end and the receiving end can infer it, or may be a reference constellation previously set by the transmitting end and the receiving end, which is It may be the same as described above.

The single constellation-based pilot symbol transmission method as described above is a method that can be effective when it is assumed that there is no significant difference in channel state information for signals transmitted through different constellations. According to the method described above, it is efficient because pilot symbol overhead can occur the least, and the overhead for reporting channel state information is also advantageous.

As another embodiment, channel state information may be estimated using pilot symbols transmitted through multi-constellation (S3702). In this case, the receiving end may receive the pilot symbol through at least one transmission opportunity assigned to each pilot symbol based on each constellation. That is, when receiving pilot symbols based on multiple constellations, the receiving end can receive pilot symbols at least once for each constellation included in the multi-constellation or for each pre-selected partial constellation.

The receiving end may set the average value of individual channel state information estimated from pilot symbols for each constellation as channel state information and report it to the transmitting end (S3703). This is for a multi-estimation single reporting method, and can be applied when it can be assumed that the quality of signals received through constellations through different channels does not significantly differ.

Alternatively, the receiving end may report channel state information estimated from pilot symbols for each constellation. In this case, multiple channel state information reports (S3703) may occur. According to this, the highest accuracy can be secured by estimating all channels experienced by pilot symbols received through all different constellations, but the highest reporting overhead can be obtained.

As another embodiment, the receiving end includes an individual channel estimation value estimated from pilot symbols for each constellation, that is, an average value for individual channel state information, and channel state information estimated from pilot symbols for each constellation for the average value. difference can be reported. In this case, multiple channel state information reports (S3703) may occur.

As another embodiment, after determining a reference constellation among a plurality of constellations, the receiving end estimates channel state information from pilot symbols for the reference constellation, and the channel state information of the pilot symbols for each of the remaining constellations is the reference. As a difference from the channel state information estimated through the constellation, this may be reported to the transmitter (S3703). Here, the reference constellation may be a reference constellation having a phase value inferred by the base station, which may be the same as described above. If the receiving end can know about the reference constellation, this embodiment can be applied. In addition, this embodiment may be preferably used when channel state information for pilot symbols transmitted based on each constellation is not significantly different.

Multi-pilot symbol transmission transmitted through such multi-constellation may be a method applicable when channels for transmitting pilot symbols based on each constellation are different from each other or expected to be so.

Meanwhile, when reporting the channel state information to the transmitter, a reporting method may vary depending on the type of channel state information. That is, they may be reported differently. For example, channel state information on beam direction may be reported as an average value, and channel state information on channel quality may be reported for all antenna subsets.

According to this, after estimating channel state information for pilot symbols that have experienced different channels, one reference value and a difference thereof can be reported. In addition, the above embodiments of estimation and reporting may be complementary to each other.

Meanwhile, in estimating channel state information using pilot symbols transmitted through multiple antennas for multiple constellations, when the channel quality estimated from some pilot symbols is lower than a specific threshold range, the receiving end determines the constellations from the constellations. It is possible to report channel quality for a modulation level (or constellation) that does not include a corresponding constellation point while satisfying the estimated effective signal-to-noise and interference ratio (SINR, Signal to Interference plus Noise Ratio). In this case, it is also possible to report including information on the modulation level, constellation point, or excluded constellation that was excluded, that is, judged to be below the threshold value, and which constellation point or constellation is below the threshold value or above can be reported, including Here, the effective SINR may mean an SINR expected to be experienced by the receiver in consideration of the receiver type and transmission mode. Here, the threshold may be defined as a parameter on receiver implementation.

Meanwhile, when the pilot symbol based on the multi-constellation is received, the channel state information may be reported differently for each type of channel state information. That is, according to the type of the channel state information, for example, the method of reporting only the average value, the method of reporting the difference between the average value and each channel state information, and the method of reporting all of the respective channel state information, etc. can be reported in a variety of ways, including

Meanwhile, the pilot symbol may be transmitted after the base station dynamically selects whether to use multi-constellation or single-constellation based on channel similarity, which may be the same as described above.

The receiving end determines the optimal beam direction for the channel between the transmitting end and the receiving end, reports it as channel state information, and the transmitting end may transmit a signal to the receiving end based on the determined beam direction. As another example, it may be possible for the transmitting end to directly determine the optimal beam direction based on the channel state information reported from the receiving end.

Meanwhile, as an embodiment, a pilot symbol and/or signal may be transmitted using a 1-bit DAC. The direction of the determined beam may be different for each bit of the signal, which may be the same as described above.

38 is a diagram illustrating an operation method of a transmitter according to an embodiment of the present disclosure. As mentioned above, the receiving end and the transmitting end mentioned below may be devices or entities including a terminal or a base station.

First, the transmitter may transmit a pilot symbol to the receiver (S3801). The transmitter may transmit pilot symbols based on a single constellation or transmit pilot symbols based on multiple constellations.

According to the above-described embodiment, when a transmitter transmits a pilot symbol based on a single constellation, the pilot symbol may be transmitted using only constellation points included in one reference constellation axis.

) 이내에서 송신단이 보유한 성상도 셋 (

)에 대하여 일부의 성상도에 대한 안테나 서브셋에서 파일럿 심볼을 전송할 수 있다.According to another embodiment described above, when the transmitter transmits a pilot symbol based on multi-constellation, the transmitter performs a channel coherent time (channel coherent time,

), three constellations possessed by the transmitter within (

), pilot symbols may be transmitted in antenna subsets for some constellations.

)이내에서 송신단이 보유한 성상도 셋 (

)에 대한 파일럿 심볼이 적어도 한번 이상 전송되도록 할 수 있다. 즉, 현재 성상도 패널이 총 네 개인 경우,

이내에 4n (n: 양의 정수 (positive integer))의 파일럿 심볼 전송 기회를 갖도록 할 수 있다. According to another embodiment described above, the transmitting end has a channel coherent time (channel coherent time,

) Within three constellations possessed by the transmitter (

) may be transmitted at least once. That is, if there are currently four constellation panels in total,

It is possible to have 4n (n: positive integer) pilot symbol transmission opportunities within the range.

As described above, after the receiving end estimates the channel state information based on the pilot symbol, the transmitting end may receive a report (S3802). In this case, the channel state information may include beam direction information, which may be previously determined and reported based on other channel state information estimated by the receiving end. The type of channel state information or the method for the transmitter to report and receive the channel state information may be the same as described above with reference to other drawings.

Thereafter, the transmitter may transmit a signal by applying the beam direction determined based on the channel state information (S3803). When transmitting a signal according to the determined beam direction, a 1-bit DAC may be used, and different beams may be applied to bits constituting the same modulation symbol and transmitted.

Meanwhile, in the drawings, it is shown that the receiving end determines the optimal beam direction and reports it as channel state information, but this corresponds to an embodiment. Accordingly, it is possible for the transmitter to receive the channel state information and determine the optimal beam direction based on this, and the present disclosure is not limited thereto.

39 is a block diagram of a transmitter according to an embodiment of the present disclosure. The transmitter of FIG. 39 may perform the operation method of the transmitter of FIG. 38 . Also, as mentioned above, the receiving end and the transmitting end mentioned below may be devices or entities including a terminal or a base station. Also, the transmitter may be based on a 1-bit DAC/ADC.

The transmitter may include a modulator 3901, a precoder 3902, an RF unit 3903, an analog BF unit 3904, and a multi-panel 3905 based on multiple antennas, which are functions and roles of the transmitter. Since it is a drawing for explaining, each function may be implemented as a module, unit, processor, hardware, software, etc., and may be implemented as one or a combination of two or more, and is not limited to a specific implementation method.

와 같이 표현될 수 있다. 여기서,

는 디지털 프리코더를 의미하므로, 디지털 빔 형성 (혹은 디지털 프리코딩)을 고려하지 않는다면, 생략 가능할 수 있다. 또한,

는 아날로그 빔 형성기(3904)를 의미하므로, 아날로그 빔 형성을 고려하지 않는다면, 생략 가능할 수 있다.As an embodiment, the transmitting end may first perform appropriate processing on the signal through the modulator 3901 and then go through a process related to digital beam forming through a precoder 3902. The precoder 3902 applied by the transmitter may include a beamformer. Precoders including beamformers

can be expressed as here,

Since denotes a digital precoder, it may be omitted if digital beamforming (or digital precoding) is not considered. also,

Since denotes the analog beamformer 3904, it can be omitted if analog beamforming is not considered.

으로 표현될 수 있다. 여기서,

는

크기를 갖는 일반적인 디지털 프리코더를 의미하고,

는

크기를 갖는 대각행렬 행태로서 안테나 그룹 간 위상 보정 프리코더를 의미할 수 있다. 여기서,

는

크기를 갖는 대각행렬 형태로서 위상 정의 안테나 선택 프리코더를 의미할 수 있다. As an embodiment, when performing phase definition antenna subset selection and/or phase correction in the digital domain, the digital precoder

can be expressed as here,

Is

It means a general digital precoder having the size,

Is

As a diagonal matrix behavior having a size, it may mean a phase correction precoder between antenna groups. here,

Is

In the form of a diagonal matrix having a size, it may mean a phase-defining antenna selection precoder.

는 위상 정의 안테나 선택 기능, 위상 보정 기능의 포함 여부에 따라

혹은

으로 표현될 수 있다. 이때,

는 전송 스트림 수를 의미할 수 있다.

은 RF 체인(3903) 수를 의미하는데, 완전 디지털 빔 프리코더 및/혹은 빔 형성기만을 고려할 경우, 전체 안테나의 수와 동일(

)할 수 있다. 다만, 서브 어레이 혹은 다중 패널 기반의 하이브리드 빔 형성기를 고려할 경우, 서브 어레이 수 혹은 패널 수(

)(3905)일 수 있다.On the other hand, digital precoders

depends on whether the phase definition antenna selection function and phase correction function are included.

or

can be expressed as At this time,

may mean the number of transport streams.

denotes the number of RF chains 3903, which is equal to the total number of antennas when only fully digital beam precoders and/or beamformers are considered (

)can do. However, when considering a sub-array or multi-panel-based hybrid beam former, the number of sub-arrays or panels (

) (3905).

는 패널 당 안테나 수를,

는 송신단의 패널 수(3905)를 의미할 수 있다. 한편, 상기에서 설명된 식은 1-D 안테나 어레이를 기준으로 특정 안테나 구성에 대한 것으로 안테나 구성에 따라 변경될 수 있다.here,

is the number of antennas per panel,

may mean the number of panels 3905 of the transmitter. Meanwhile, the equation described above is for a specific antenna configuration based on the 1-D antenna array and may be changed according to the antenna configuration.

로 표현될 수 있다. 여기서,

는

크기를 갖는 아날로그 빔 형성기를 의미하고,

는

크기를 갖는 안테나 그룹 간 위상 보정 프리코더를 의미한다.

는

크기를 갖는 위상 정의 안테나 선택 프리코더를 의미한다. 아날로그 빔 형성기

는 위상 정의 안테나 선택 기능, 위상 보정 기능의 포함 여부에 따라

혹은

으로 될 수 있다. 한편, 상기 식은 1-D 안테나 어레이를 기준으로 특정 안테나 구성에 대한 것으로 안테나 구성에 따라 변경될 수 있다.As an embodiment, when the analog beamformer 3904 performs phase-defining antenna subset selection and/or phase correction,

can be expressed as here,

Is

It means an analog beamformer having a size,

Is

It means a phase correction precoder between antenna groups having a size.

Is

It means a phase-defining antenna selection precoder having a size. analog beamformer

depends on whether the phase definition antenna selection function and phase correction function are included.

or

can be Meanwhile, the above formula is for a specific antenna configuration based on a 1-D antenna array and may be changed according to the antenna configuration.

For channel state information estimated and/or reported based on a single constellation, the transmitter may transmit pilot symbols and/or signals after performing phase correction based on the constellation to be applied. To this end, the transmitter may include a phase correction module for the reference constellation. In this case, the transmitter may apply and transmit different beams to bits constituting the same modulation symbol.

Also, the phase correction module may be included in an analog beamformer or a digital precoder.

According to the present disclosure, in communication using a terahertz band, it is possible to perform realizable signal transmission and reception in consideration of power consumption and the like by utilizing a massive MIMO (multi-MIMO) technology, which is essentially required. In particular, we propose a procedure and method for effectively obtaining beamforming gain using multiple antennas while overcoming nonlinearity and modulation order limitations caused by a transmitter with a 1-bit DAC. This enables higher-order modulation based on improved SINR in a power-efficient system, thereby increasing the data rate.

Steps of a method or algorithm described in connection with the embodiments disclosed herein may be directly embodied as hardware executed by a processor, a software module, or a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a storage medium (ie, memory) such as a hard disk, a removable disk, a CD-ROM, or storage. An exemplary storage medium is coupled to the processor, and the processor can read information from, and write information to, the storage medium. Alternatively, the storage medium may be integral with the processor, and the processor and storage medium may reside within an application specific integrated circuit (ASIC). An ASIC may reside within a terminal, or alternatively, a processor and a storage medium may reside as separate components within a terminal.

The present disclosure, while providing various embodiments, proposes implementation and feasible transmission and reception technology in consideration of power consumption and the like in utilizing massive MIMO technology, which is essential for communication using a terahertz (THz) band. did In particular, we propose a method for overcoming nonlinearity caused by low-resolution DACs including 1-bit DACs and the resulting modulation order limitations. This enables higher order modulation in a power efficient system, thereby increasing the data rate.

Exemplary methods of the present disclosure are expressed as a series of operations for clarity of explanation, but this is not intended to limit the order in which steps are performed, and each step may be performed concurrently or in a different order, if necessary. In order to implement the method according to the present disclosure, other steps may be included in addition to the exemplified steps, other steps may be included except for some steps, or additional other steps may be included except for some steps.

Various embodiments of the present disclosure are intended to explain representative aspects of the present disclosure, rather than listing all possible combinations, and matters described in various embodiments may be applied independently or in combination of two or more.

In addition, various embodiments of the present disclosure may be implemented by hardware, firmware, software, or a combination thereof. For implementation by hardware, one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), general-purpose It may be implemented by a processor (general processor), controller, microcontroller, microprocessor, or the like.

The scope of the present disclosure is software or machine-executable instructions (eg, operating systems, applications, firmware, programs, etc.) that cause operations in accordance with the methods of various embodiments to be executed on a device or computer, and such software or It includes a non-transitory computer-readable medium in which instructions and the like are stored and executable on a device or computer.

It is obvious that examples of the proposed schemes described above may also be included as one of the implementation methods of the present disclosure, and thus may be regarded as a kind of proposed schemes. In addition, the above-described proposed schemes may be implemented independently, but may also be implemented in a combination (or merged) form of some proposed schemes. Information on whether the proposed methods are applied (or information on the rules of the proposed methods) may be defined so that the base station informs the terminal through a predefined signal (eg, a physical layer signal or a higher layer signal). .

The present disclosure may be embodied in other specific forms without departing from the technical ideas and essential characteristics described in the present disclosure. Accordingly, the above detailed description should not be construed as limiting in all respects and should be considered illustrative. The scope of the present disclosure should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent range of the present disclosure are included in the scope of the present disclosure. In addition, claims that do not have an explicit citation relationship in the claims may be combined to form an embodiment or may be included as new claims by amendment after filing.

Embodiments of the present disclosure may be applied to various wireless access systems. As an example of various wireless access systems, there is a 3rd Generation Partnership Project (3GPP) or 3GPP2 system.

Embodiments of the present disclosure may be applied not only to the various wireless access systems, but also to all technical fields to which the various wireless access systems are applied. Furthermore, the proposed method can be applied to mmWave and THz communication systems using ultra-high frequency bands.

Additionally, embodiments of the present disclosure may be applied to various applications such as free-running vehicles and drones.

Claims (15)

In a method of operating a user equipment (UE) in a wireless communication system,
Receiving a pilot symbol from a base station;
estimating channel state information (CSI) based on the received pilot symbol and reporting the estimated channel state information to the base station;
Receiving a signal from the base station according to a direction of a beam determined based on the estimated channel state information; including, a method of operating a terminal. According to claim 1,
The pilot symbol is based on a single constellation. According to claim 2,
When receiving the pilot symbol based on the single constellation,
The single constellation is a reference constellation indicated by the base station and inferred by the terminal. According to claim 1,
The pilot symbol is based on a multi-constellation, operating method of a terminal. According to claim 4,
When receiving the pilot symbol based on the multi-constellation,
The method of operation of the terminal, wherein the terminal receives the pilot symbol at least once for each constellation included in the multi-constellation or for each predetermined partial constellation. According to claim 5,
When receiving the pilot symbol based on the multi-constellation,
wherein the channel state information transmitted by the terminal further includes information about a difference between the average value and each channel state information estimated from pilot symbols based on the constellations. According to claim 4,
When receiving the pilot symbol based on the multi-constellation,
The channel state information is estimated as an average value for each channel state information estimated from pilot symbols based on each constellation. According to claim 4,
When receiving the pilot symbol based on the multi-constellation,
The channel state information includes each channel state information estimated from pilot symbols based on each constellation. According to claim 4,
When receiving the pilot symbol based on the multi-constellation,
The channel state information includes channel state information estimated from pilot symbols based on a reference constellation having a phase value that the terminal and the base station already know or have a phase value that the base station can infer, and pilots based on other constellations. A method of operating a terminal, including a difference with each channel state information estimated from a symbol. According to claim 4,
When receiving the pilot symbol based on the multi-constellation,
The channel state information includes only the channel quality of a constellation point for which the estimated channel quality is determined to be equal to or higher than a preset threshold value. According to claim 4,
When receiving the pilot symbol based on the multi-constellation,
The channel state information,
A method of operating a terminal that is reported differently for each type of channel state information. According to claim 1,
The pilot symbol received by the terminal,
A method of operating a terminal in which the base station dynamically selects whether to use multiple constellations or single constellations based on channel similarity. According to claim 1,
The direction of the determined beam is different for each bit of the signal, the operating method of the terminal. In a terminal in a wireless communication system,
at least one transmitter;
at least one receiver;
at least one processor; and
at least one memory operatively connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform a specific operation;
The specific action is:
receiving a pilot symbol from a base station;
estimating channel state information (CSI) based on the received pilot symbol;
Including, reporting the estimated channel state information to the base station. In a base station operating in a wireless communication system,
at least one transmitter;
at least one receiver;
at least one processor; and
at least one memory operatively connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform a specific operation;
The specific action is:
Transmitting a pilot symbol to a terminal;
Receiving a report of Channel State Information (CSI) estimated based on the pilot symbol from the terminal;
Transmitting a signal to the terminal based on the direction of the beam determined based on the channel state information; including, the base station.

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