WO2023042936A1

WO2023042936A1 - Receiver structure for reducing noise according to direction of arrival in wireless communication system and method therefor

Info

Publication number: WO2023042936A1
Application number: PCT/KR2021/012693
Authority: WO
Inventors: 정재훈; 금승원; 노상미; 김당오; 이주용; 조동호
Original assignee: 엘지전자 주식회사; 한국과학기술원
Priority date: 2021-09-16
Filing date: 2021-09-16
Publication date: 2023-03-23
Also published as: KR20240055719A

Abstract

Provided are: a receiver structure for reducing noise of a low-noise amplifier (LNA) according to a direction of arrival (DoA) in a wireless communication system; and a method therefor. User equipment (UE): determines a relationship between a direction of arrival (DoA) and a signal-to-noise ratio (SNR) according to the number of oversampling and a change in an attenuator; and selects, from among a first receiver structure and a second receiver structure on the basis of an estimated DoA of a received signal, any one receiver structure maximizing the SNR.

Description

Receiver structure and method for reducing noise according to arrival direction in wireless communication system

The present specification relates to a receiver structure and method for reducing noise of a low-noise amplifier (LNA) according to a direction of arrival (DoA) in a wireless communication system.

3rd Generation Partnership Project (3GPP) Long-Term Evolution (LTE) is a technology for enabling high-speed packet communication. Many schemes have been proposed for LTE goals, cost reduction for users and operators, improvement in service quality, coverage expansion, and system capacity increase. 3GPP LTE requires cost reduction per bit, improvement in service usability, flexible use of frequency bands, simple structure, open interface, and appropriate power consumption of terminals as high-level requirements.

Work has begun on the International Telecommunication Union (ITU) and 3GPP to develop requirements and specifications for New Radio (NR) systems. 3GPP identifies the technical components needed to successfully standardize NRs that meet both urgent market needs and the longer-term requirements of the ITU Radio Communication Sector (ITU-R) International Mobile Telecommunications (IMT)-2020 process in a timely manner. and must be developed. In addition, NR should be able to use any spectrum band up to at least 100 GHz that can be used for wireless communication even in the distant future.

NR targets a single technology framework that covers all deployment scenarios, usage scenarios and requirements, including enhanced mobile broadband (eMBB), massive machine type-communications (mMTC), ultra-reliable and low latency communications (URLC), and more. do. NR must be inherently forward compatible.

With the commercialization of NR corresponding to the 5th generation (5G) mobile communication technology, research on the 6th generation (6G) mobile communication technology has begun. In the 6th generation mobile communication technology, it is expected to utilize a frequency band of 100 GHz or more. As a result, it is expected that the frequency to be used can be increased by more than 10 times compared to 5G, and the possibility of utilizing spatial resources can be further increased. This frequency band above 100 GHz may be referred to as sub-THz.

In the terahertz and/or sub-terahertz bands, the antenna spacing can be greatly reduced according to the center frequency, and the number of antennas can be greatly increased to overcome pathloss. Each antenna can be connected to a low-noise amplifier (LNA) for noise cancellation. As the number of antennas increases, it is difficult to use high-performance LNAs because a large number of LNAs must be integrated in a small space. expected In addition, since it is difficult to fabricate a radio frequency (RF) element in the terahertz and/or sub-terahertz band, the noise figure (NF) of the LNA is expected to deteriorate.

Since the NF of the LNA greatly affects communication quality, a method and/or device for reducing the NF may be required.

The present specification analyzes the signal-to-noise ratio (SNR) after beamforming according to the direction of arrival (DoA) of the received signal in a situation in which mutual coupling between antennas is considered, and thus variable We propose a receiver structure that can obtain an optimal beamforming SNR gain according to DoA by proposing a noise shaping (NS) structure.

In one aspect, a method performed by a user equipment (UE) in a wireless communication system is provided. The method includes determining a relationship between a direction of arrival (DoA) and a signal-to-noise ratio (SNR) according to a change in the number of oversampling and an attenuator, and determining an estimated DoA of a received signal. and selecting one of the first receiver structure and the second receiver structure based on which the SNR is maximized.

In another aspect, an apparatus implementing the method is provided.

This specification may have various effects.

For example, in a massive array antenna structure in which a large number of antennas are disposed, noise of an LNA with high directivity can be effectively reduced.

For example, LNA noise can be minimized by changing the receiver structure based on the DoA of the received signal.

For example, it is possible to maximize the receive beamforming SNR by overcoming the SNR limit at the receiver by the LNA.

Effects that can be obtained through specific examples of the present specification are not limited to the effects listed above. For example, various technical effects that a person having ordinary skill in the related art can understand or derive from the present specification may exist. Accordingly, the specific effects of the present specification are not limited to those explicitly described in the present specification, and may include various effects that can be understood or derived from the technical features of the present specification.

1 shows an example of a communication system to which an implementation of the present specification is applied.

2 shows an example of a wireless device to which implementations of the present disclosure apply.

3 shows an example of a wireless device to which implementations of the present disclosure apply.

4 shows an example of a UE to which the implementation of the present specification is applied.

5 shows an example of a unit structure for performing NS to which the implementation of the present specification is applied.

6 shows an example of an ideal noise transfer function (NTF) when NS is performed according to a unit structure to which the implementation of the present specification is applied.

7 shows an example of a continuous structure for performing NS to which the implementation of the present specification is applied.

8 shows an example of NTF when performing NS according to a contiguous structure to which the implementation of the present specification is applied.

9 shows an example of 16 array antennas to which the implementation of the present specification is applied and beamforming gains accordingly.

10 shows an example of a system for estimating/analyzing/calculating a receive beamforming SNR gain considering both mutual coupling and NS to which the implementation of the present specification is applied.

11 shows an example of a method performed by a UE to which an implementation of the present specification is applied.

12 shows an example of a CS structure to which the implementation of the present specification is applied.

13 shows an example of a CTS structure to which the implementation of the present specification is applied.

14 shows an example in which noise power reduction performance of a CS structure and a TS structure to which the implementation of the present specification is applied is compared.

15 shows another example of comparing noise power reduction performance of a CS structure and a TS structure to which the implementation of the present specification is applied.

16 shows an example of comparing beamforming SNR gain performance of a CS structure and a TS structure to which the implementation of the present specification is applied.

17 shows another example of comparing beamforming SNR gain performance of a CS structure and a TS structure to which the implementation of the present specification is applied.

18 shows an example of a CS structure of a 2D array antenna to which the implementation of the present specification is applied.

19 shows an example of a TS structure of a 2D array antenna to which the implementation of the present specification is applied.

The following techniques, devices and systems may be applied to various wireless multiple access systems. 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, a system, and a SC-FDMA (Single Access) system. It includes a Carrier Frequency Division Multiple Access (MC-FDMA) system and a Multi-Carrier Frequency Division Multiple Access (MC-FDMA) system. CDMA may be implemented through a radio technology such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA may be implemented through a radio technology such as Global System for Mobile communications (GSM), General Packet Radio Service (GPRS), or Enhanced Data rates for GSM Evolution (EDGE). OFDMA may be implemented through a radio technology such as Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, or Evolved UTRA (E-UTRA). UTRA is part of the Universal Mobile Telecommunications System (UMTS). 3rd Generation Partnership Project (3GPP) Long-Term Evolution (LTE) is a part of Evolved UMTS (E-UMTS) using E-UTRA. 3GPP LTE uses OFDMA in downlink (DL) and SC-FDMA in uplink (UL). The evolution of 3GPP LTE includes LTE-A (Advanced), LTE-A Pro, and/or 5G New Radio (NR).

For ease of explanation, implementations herein are primarily described in the context of a 3GPP-based wireless communication system. However, the technical characteristics of the present specification are not limited thereto. For example, although the following detailed description is provided based on a mobile communication system corresponding to a 3GPP-based wireless communication system, aspects of the present disclosure that are not limited to a 3GPP-based wireless communication system may be applied to other mobile communication systems.

For terms and technologies not specifically described among terms and technologies used in this specification, reference may be made to wireless communication standard documents published prior to this specification.

In this specification, "A or B" may mean "only A", "only B", or "both A and B". In other words, "A or B (A or B)" in the present specification may be interpreted as "A and/or B (A and/or B)". For example, “A, B or C” as used herein means “only A”, “only B”, “only C”, or “any and all combinations of A, B and C ( any combination of A, B and C)".

A slash (/) or a comma (comma) used in this specification may mean "and/or". For example, "A/B" can mean "A and/or B". Accordingly, "A/B" may mean "only A", "only B", or "both A and B". For example, "A, B, C" may mean "A, B or C".

In this specification, "at least one of A and B" may mean "only A", "only B", or "both A and B". In addition, in this specification, the expression “at least one of A or B” or “at least one of A and/or B” means “A and It can be interpreted the same as "at least one of A and B".

In addition, in the present specification, "at least one of A, B and C" means "only A", "only B", "only C", or "A, B and C" It may mean "any combination of A, B and C". In addition, "at least one of A, B or C" or "at least one of A, B and/or C" means It may mean "at least one of A, B and C".

Also, parentheses used in this specification may mean “for example”. Specifically, when indicated as “control information (PDCCH)”, “PDCCH” may be suggested as an example of “control information”. In other words, "control information" in this specification is not limited to "PDCCH", and "PDCCH" may be suggested as an example of "control information". Also, even when displayed as “control information (ie, PDCCH)”, “PDCCH” may be suggested as an example of “control information”.

Technical features that are individually described in one drawing in this specification may be implemented individually or simultaneously.

Although not limited thereto, various descriptions, functions, procedures, proposals, methods and/or operational flowcharts disclosed herein may be applied to various fields requiring wireless communication and/or connectivity (eg, 5G) between devices.

Hereinafter, this specification will be described in more detail with reference to the drawings. In the following drawings and/or description, the same reference numbers may refer to the same or corresponding hardware blocks, software blocks and/or function blocks unless otherwise indicated.

The 5G usage scenario shown in FIG. 1 is only an example, and the technical features of this specification can be applied to other 5G usage scenarios not shown in FIG. 1 .

There are three main categories of requirements for 5G: (1) enhanced mobile broadband (eMBB) category, (2) massive machine type communication (mMTC) category, and (3) ultra-reliable low-latency communications. (URLLC; Ultra-Reliable and Low Latency Communications) category.

Referring to FIG. 1 , a communication system 1 includes wireless devices 100a to 100f, a base station (BS) 200 and a network 300 . Although FIG. 1 illustrates a 5G network as an example of a network of the communication system 1, the implementation herein is not limited to the 5G system and may be applied to future communication systems beyond the 5G system.

Base station 200 and network 300 may be implemented as wireless devices, and certain wireless devices may act as base station/network nodes in conjunction with other wireless devices.

The wireless devices 100a to 100f represent devices that perform communication using Radio Access Technology (RAT) (eg, 5G NR or LTE), and may also be referred to as communication/wireless/5G devices. The wireless devices 100a to 100f are, but are not limited to, a robot 100a, a vehicle 100b-1 and 100b-2, an extended reality (XR) device 100c, a portable device 100d, and a home appliance. It may include a product 100e, an Internet-Of-Things (IoT) device 100f, and an artificial intelligence (AI) device/server 400 . For example, the vehicle may include a vehicle having a wireless communication function, an autonomous vehicle, and a vehicle capable of performing inter-vehicle communication. Vehicles may include Unmanned Aerial Vehicles (UAVs), such as drones. XR devices may include augmented reality (AR)/virtual reality (VR)/mixed reality (MR) devices, and are mounted on vehicles, televisions, smartphones, computers, wearable devices, home appliances, digital signs, vehicles, robots, etc. It may be implemented in the form of a Head-Mounted Device (HMD) or Head-Up Display (HUD). Portable devices may include smart phones, smart pads, wearable devices (eg smart watches or smart glasses) and computers (eg laptops). Appliances may include TVs, refrigerators, and washing machines. IoT devices can include sensors and smart meters.

In this specification, the wireless devices 100a to 100f may be referred to as User Equipment (UE). The UE includes, for example, a mobile phone, a smart phone, a notebook computer, a digital broadcast terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation system, a slate PC, a tablet PC, an ultrabook, a vehicle, and an autonomous driving function. vehicles, connected cars, UAVs, AI modules, robots, AR devices, VR devices, MR devices, hologram devices, public safety devices, MTC devices, IoT devices, medical devices, fintech devices (or financial devices), security devices , weather/environment devices, 5G service related devices, or 4th industrial revolution related devices.

For example, a UAV may be an aircraft that is navigated by a radio control signal without a human being on board.

For example, a VR device may include a device for implementing an object or background of a virtual environment. For example, an AR device may include a device implemented by connecting a virtual world object or background to a real world object or background. For example, an MR apparatus may include a device implemented by merging an object or a background of the virtual world with an object or a background of the real world. For example, the hologram device may include a device for realizing a 360-degree stereoscopic image by recording and reproducing stereoscopic information using an interference phenomenon of light generated when two laser lights, called holograms, meet.

For example, a public safety device may include an image relay device or imaging device wearable on a user's body.

For example, MTC devices and IoT devices may be devices that do not require direct human intervention or manipulation. For example, MTC devices and IoT devices may include smart meters, vending machines, thermometers, smart light bulbs, door locks, or various sensors.

For example, a medical device may be a device used for the purpose of diagnosing, treating, mitigating, treating or preventing a disease. For example, a medical device may be a device used to diagnose, treat, mitigate, or correct an injury or damage. For example, a medical device may be a device used for the purpose of inspecting, replacing, or modifying structure or function. For example, the medical device may be a device used for fertility control purposes. For example, a medical device may include a device for treatment, a device for driving, a device for (in vitro) diagnosis, a hearing aid, or a device for procedures.

For example, a security device may be a device installed to prevent possible danger and to maintain safety. For example, a security device may be a camera, closed circuit television (CCTV), recorder, or black box.

For example, a fintech device may be a device capable of providing financial services such as mobile payments. For example, a fintech device may include a payment device or POS system.

For example, the weather/environment device may include a device that monitors or predicts the weather/environment.

The wireless devices 100a to 100f may be connected to the network 300 through the base station 200 . 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 400 through the network 300. The network 300 may be configured using a 3G network, a 4G (eg LTE) network, a 5G (eg NR) network, and a network after 5G. The wireless devices 100a to 100f may communicate with each other through the base station 200/network 300, but communicate directly without going through the base station 200/network 300 (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, IoT devices (eg, sensors) may directly communicate with other IoT devices (eg, sensors) or other wireless devices 100a to 100f.

A wireless communication/

connection

150a, 150b, 150c may be established between the wireless devices 100a-100f and/or between the wireless devices 100a-100f and the base station 200 and/or between the base stations 200. Here, wireless communication/connection refers to uplink/downlink communication 150a, sidelink communication 150b (or D2D (Device-To-Device) communication), base station communication 150c (eg, relay, IAB (Integrated) It can be established through various RATs (e.g., 5G NR), such as Access and Backhaul). The wireless devices 100a to 100f and the base station 200 may transmit/receive radio signals to each other through the wireless communication/

connection

150a, 150b, and 150c. 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 specification, various configuration information setting processes for transmitting / receiving radio signals, various signal processing processes (eg, channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), And at least a part of a resource allocation process may be performed.

AI refers to the field of studying artificial intelligence or a methodology to create it, and machine learning refers to the field of defining various problems dealt with in the field of artificial intelligence and studying methodologies to solve them. Machine learning is also defined as an algorithm that improves the performance of a certain task through constant experience.

A robot may refer to a machine that automatically processes or operates a given task based on its own abilities. In particular, a robot having a function of recognizing an environment and performing an operation based on self-determination may be referred to as an intelligent robot. Robots can be classified into industrial, medical, household, military, etc. according to the purpose or field of use. The robot may perform various physical operations such as moving a robot joint by having a driving unit including an actuator or a motor. In addition, the movable robot includes wheels, brakes, propellers, and the like in the driving unit, and can run on the ground or fly in the air through the driving unit.

Autonomous driving refers to a technology that drives by itself, and an autonomous vehicle refers to a vehicle that travels without a user's manipulation or with a user's minimal manipulation. For example, autonomous driving includes technology to keep the driving lane, technology to automatically adjust the speed such as adaptive cruise control, technology to automatically drive along a set route, and technology to automatically set a route when a destination is set. All technologies may be included. A vehicle includes a vehicle having only an internal combustion engine, a hybrid vehicle having both an internal combustion engine and an electric motor, and an electric vehicle having only an electric motor, and may include not only automobiles but also trains and motorcycles. Self-driving vehicles can be viewed as robots with self-driving capabilities.

Augmented reality is a collective term for VR, AR, and MR. VR technology provides only CG images of objects or backgrounds in the real world, AR technology provides CG images created virtually on top of images of real objects, and MR technology provides CG images by mixing and combining virtual objects in the real world. It is a skill. MR technology is similar to AR technology in that it shows real and virtual objects together. However, there is a difference in that virtual objects are used to supplement real objects in AR technology, whereas virtual objects and real objects are used with equal characteristics in MR technology.

NR supports a number of 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 wider A wider carrier bandwidth is supported, and when the SCS is 60 kHz or higher, a bandwidth greater than 24.25 GHz is supported to overcome phase noise.

The NR frequency band may be defined as two types of frequency ranges (FR1 and FR2). The number of frequency ranges can be changed. For example, the frequency ranges of the two types FR1 and FR2 may be shown in Table 1 below. For convenience of explanation, among the frequency ranges used in the NR system, FR1 may mean "sub 6 GHz range" and FR2 may mean "above 6 GHz range" and may be referred to as millimeter wave (MilliMeter Wave, mmW). there is.

주파수 범위 정의Frequency range definition	주파수 범위frequency range	부반송파 간격subcarrier spacing
FR1FR1	450MHz - 6000MHz450MHz - 6000MHz	15, 30, 60kHz15, 30, 60 kHz
FR2FR2	24250MHz - 52600MHz24250MHz - 52600MHz	60, 120, 240kHz60, 120, 240 kHz

As described above, the number of frequency ranges of the NR system can be changed. For example, FR1 may include a band of 410 MHz to 7125 MHz as shown in Table 2 below. That is, FR1 may include a frequency band of 6 GHz (or 5850, 5900, 5925 MHz, etc.) or higher. For example, a frequency band of 6 GHz (or 5850, 5900, 5925 MHz, etc.) or higher included in FR1 may include an unlicensed band. The unlicensed band may be used for various purposes, and may be used, for example, for communication for vehicles (eg, autonomous driving).

주파수 범위 정의Frequency range definition	주파수 범위frequency range	부반송파 간격subcarrier spacing
FR1FR1	410MHz - 7125MHz410MHz - 7125MHz	15, 30, 60kHz15, 30, 60 kHz
FR2FR2	24250MHz - 52600MHz24250MHz - 52600MHz	60, 120, 240kHz60, 120, 240 kHz

Here, the wireless communication technology implemented in the wireless device of the present specification may include LTE, NR, and 6G as well as narrowband IoT (NB-IoT) for low-power communication. For example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology, and may be implemented in standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above-mentioned names. . Additionally or alternatively, the wireless communication technology implemented in the wireless device of the present specification may perform communication based on LTE-M technology. For example, LTE-M technology may be an example of LPWAN technology and may be called various names such as eMTC (enhanced MTC). For example, LTE-M technologies include 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-Bandwidth Limited (non-BL), 5) LTE-MTC, and 6) LTE MTC. , and/or 7) may be implemented in at least one of various standards such as LTE M, and is not limited to the above-mentioned names. Additionally or alternatively, the wireless communication technology implemented in the wireless device of the present specification may include at least one of ZigBee, Bluetooth, and/or LPWAN considering low-power communication, and is limited to the above-mentioned names It is not. For example, ZigBee technology can create personal area networks (PANs) related to small/low-power digital communication based on various standards such as IEEE 802.15.4, and can be called various names.

Referring to FIG. 2 , the first wireless device 100 and the second wireless device 200 may transmit/receive radio signals to/from the external device through various RATs (eg, LTE and NR).

In FIG. 2, {the first wireless device 100 and the second wireless device 200} refer to {the wireless devices 100a to 100f and the base station 200} in FIG. 1, {the wireless devices 100a to 100f ) and wireless devices 100a to 100f} and/or {base station 200 and base station 200}.

The first wireless device 100 may include at least one transceiver, such as transceiver 106, at least one processing chip, such as processing chip 101, and/or one or more antennas 108.

Processing chip 101 may include at least one processor such as processor 102 and at least one memory such as memory 104 . In FIG. 2 , memory 104 is shown by way of example to be included in processing chip 101 . Additionally and/or alternatively, memory 104 may be located external to processing chip 101 .

Processor 102 may control memory 104 and/or transceiver 106 and may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flow diagrams disclosed herein. For example, the processor 102 may process information in the memory 104 to generate first information/signal and transmit a radio signal including the first information/signal through the transceiver 106 . The processor 102 may receive a radio signal including the second information/signal through the transceiver 106 and store information obtained by processing the second information/signal in the memory 104 .

Memory 104 may be operably coupled to processor 102 . Memory 104 may store various types of information and/or instructions. Memory 104 may store software code 105 embodying instructions that when executed by processor 102 perform the descriptions, functions, procedures, suggestions, methods, and/or operational flow diagrams disclosed herein. For example, software code 105 may implement instructions that, when executed by processor 102, perform the descriptions, functions, procedures, suggestions, methods, and/or operational flow diagrams disclosed herein. For example, software code 105 may control processor 102 to perform one or more protocols. For example, software code 105 may control processor 102 to perform one or more air interface protocol layers.

Here, processor 102 and memory 104 may be part of a communications modem/circuit/chip designed to implement a RAT (eg LTE or NR). Transceiver 106 may be coupled to processor 102 to transmit and/or receive wireless signals via one or more antennas 108 . Each transceiver 106 may include a transmitter and/or a receiver. The transceiver 106 may be used interchangeably with a radio frequency (RF) unit. In this specification, the first wireless device 100 may represent a communication modem/circuit/chip.

The second wireless device 200 may include at least one transceiver such as transceiver 206 , at least one processing chip such as processing chip 201 and/or one or more antennas 208 .

Processing chip 201 may include at least one processor such as processor 202 and at least one memory such as memory 204 . In FIG. 2 , memory 204 is shown by way of example to be included in processing chip 201 . Additionally and/or alternatively, memory 204 may be located external to processing chip 201 .

Processor 202 may control memory 204 and/or transceiver 206 and may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flow diagrams disclosed herein. For example, the processor 202 may process information in the memory 204 to generate third information/signal and transmit a radio signal including the third information/signal through the transceiver 206 . The processor 202 may receive a radio signal including the fourth information/signal through the transceiver 206 and store information obtained by processing the fourth information/signal in the memory 204 .

Memory 204 may be operably coupled to processor 202 . Memory 204 may store various types of information and/or instructions. Memory 204 may store software code 205 embodying instructions that when executed by processor 202 perform the descriptions, functions, procedures, suggestions, methods, and/or operational flow diagrams disclosed herein. For example, software code 205 may implement instructions that, when executed by processor 202, perform the descriptions, functions, procedures, suggestions, methods, and/or operational flow diagrams disclosed herein. For example, software code 205 may control processor 202 to perform one or more protocols. For example, software code 205 may control processor 202 to perform one or more air interface protocol layers.

Here, the processor 202 and memory 204 may be part of a communications modem/circuit/chip designed to implement a RAT (eg LTE or NR). The transceiver 206 may be coupled to the processor 202 to transmit and/or receive wireless signals via one or more antennas 208 . Each transceiver 206 may include a transmitter and/or a receiver. The transceiver 206 may be used interchangeably with the RF unit. In this specification, the second wireless device 200 may represent a communication modem/circuit/chip.

Hereinafter, hardware elements of the

wireless devices

100 and 200 will be described in more detail. Although not limited to this, one or more protocol layers may be implemented by one or

more processors

102, 202. For example, one or

more processors

102 and 202 may include one or more layers (eg, a physical (PHY) layer, a media access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, Functional layers such as a Radio Resource Control (RRC) layer and a Service Data Adaptation Protocol (SDAP) layer) can be implemented. One or

more processors

102, 202 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 diagrams disclosed herein. can do. One or

more processors

102, 202 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

102, 202 may process PDUs, SDUs, messages, control information, data or signals containing information (e.g., baseband signal) can be generated and provided to one or more transceivers (106, 206). One or

more processors

102, 202 may receive signals (eg, baseband signals) from one or

more transceivers

106, 206, and the descriptions, functions, procedures, proposals, methods and/or operational flow diagrams disclosed herein According to the PDU, SDU, message, control information, data or information can be obtained.

One or

more processors

102, 202 may be referred to as a controller, microcontroller, microprocessor and/or microcomputer. One or

more processors

102, 202 may be implemented by hardware, firmware, software, and/or combinations 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), and/or one or more Field Programmable Gates (FPGAs). Arrays may be included in one or

more processors

102, 202. Descriptions, functions, procedures, proposals, methods and/or operational flow diagrams disclosed herein may be implemented using firmware and/or software, and firmware and/or software may be implemented to include modules, procedures, and functions. . Firmware or software configured to perform the descriptions, functions, procedures, suggestions, methods and/or operational flow diagrams disclosed herein may be included in one or

more processors

102, 202 or stored in one or

more memories

104, 204 and It can be driven by the

above processors

102 and 202. The descriptions, functions, procedures, suggestions, methods and/or operational flow diagrams disclosed herein may be implemented using firmware or software in the form of codes, instructions and/or sets of instructions.

One or

more memories

104, 204 may be coupled with one or

more processors

102, 202 and may store various types of data, signals, messages, information, programs, codes, instructions and/or instructions. The one or

more memories

104, 204 may include read-only memory (ROM), random access memory (RAM), erasable programmable ROM (EPROM), flash memory, hard drive, registers, cache memory, computer readable storage media, and/or It can be composed of a combination of One or

more memories

104, 204 may be located internally and/or external to one or

more processors

102, 202. Additionally, one or

more memories

104, 204 may be coupled to one or

more processors

102, 202 through various technologies, such as wired or wireless connections.

One or

more transceivers

106, 206 may transmit to one or more other devices user data, control information, radio signals/channels, etc., as discussed in the descriptions, functions, procedures, proposals, methods and/or operational flow diagrams disclosed herein. . One or

more transceivers

106, 206 may receive user data, control information, radio signals/channels, etc., from one or more other devices as referred to in the descriptions, functions, procedures, proposals, methods and/or operational flow diagrams disclosed herein. there is. For example, one or

more transceivers

106 and 206 may be connected to one or

more processors

102 and 202 and transmit and receive wireless signals. For example, one or

more processors

102, 202 may control one or

more transceivers

106, 206 to transmit user data, control information, radio signals, etc. to one or more other devices. In addition, one or

more processors

102, 202 may control one or

more transceivers

106, 206 to receive user data, control information, radio signals, and the like from one or more other devices.

One or

more transceivers

106, 206 may be coupled with one or

more antennas

108, 208. One or more transceivers (106, 206) via one or more antennas (108, 208) transmit user data, control information, radio signals/channels referred to in the descriptions, functions, procedures, proposals, methods and/or operational flow diagrams disclosed herein. etc. can be set to transmit and receive. In this specification, one or

more antennas

108 and 208 may be a plurality of physical antennas or a plurality of logical antennas (eg, antenna ports).

One or more transceivers (106, 206) use one or more processors (102, 202) to process received user data, control information, radio signals/channels, etc. etc. can be converted from an RF band signal to a baseband signal. One or

more transceivers

106 and 206 may convert user data, control information, and radio signals/channels processed by one or

more processors

102 and 202 from baseband signals to RF band signals. To this end, one or more of the

transceivers

106 and 206 may include (analog) oscillators and/or filters. For example, one or

more transceivers

106, 206 up-convert an OFDM baseband signal to an OFDM signal via an (analog) oscillator and/or filter under the control of one or

more processors

102, 202 and , the up-converted OFDM signal can be transmitted at the carrier frequency. One or

more transceivers

106, 206 receive OFDM signals at the carrier frequency and down-convert the OFDM signals to OFDM baseband signals via (analog) oscillators and/or filters under the control of one or more processors 102, 202 ( down-convert).

In the implementations herein, the UE can act as a transmitting device in uplink and as a receiving device in downlink. In the implementation of the present specification, a base station may operate as a receiving device in UL and as a transmitting device in DL. Hereinafter, for convenience of description, it is mainly assumed that the first wireless device 100 operates as a UE and the second wireless device 200 operates as a base station. For example, the processor 102 coupled to, mounted on, or shipped to the first wireless device 100 may perform UE operations in accordance with implementations herein or may operate the transceiver 106 to perform UE operations in accordance with implementations herein. can be configured to control A processor 202 connected to, mounted on, or shipped to the second wireless device 200 is configured to perform base station operations in accordance with implementations herein or to control the transceiver 206 to perform base station operations in accordance with implementations herein. It can be.

In this specification, a base station may be referred to as a Node B, an eNode B (eNB), or a gNB.

A wireless device may be implemented in various forms according to use cases/services (see FIG. 1).

Referring to FIG. 3 , the

wireless devices

100 and 200 may correspond to the

wireless devices

100 and 200 of FIG. 2 and may be configured by various components, devices/parts and/or modules. For example, each

wireless device

100 , 200 may include a communication device 110 , a control device 120 , a memory device 130 and additional components 140 . The communication device 110 may include a communication circuit 112 and a transceiver 114 . For example, communication circuitry 112 may include one or

more processors

102, 202 of FIG. 2 and/or one or

more memories

104, 204 of FIG. For example, transceiver 114 may include one or

more transceivers

106, 206 of FIG. 2 and/or one or

more antennas

108, 208 of FIG. The control device 120 is electrically connected to the communication device 110, the memory device 130, and the additional component 140, and controls the overall operation of each

wireless device

100, 200. For example, the control device 120 may control electrical/mechanical operation of each of the

wireless devices

100 and 200 based on programs/codes/commands/information stored in the memory device 130 . The control device 120 transmits information stored in the memory device 130 to the outside (eg, other communication devices) via the communication device 110 through a wireless/wired interface, or through a wireless/wired interface to a communication device ( 110), information received from the outside (eg, other communication devices) may be stored in the memory device 130.

The additional component 140 may be configured in various ways according to the type of the

wireless device

100 or 200. For example, additional components 140 may include at least one of a power unit/battery, an input/output (I/O) device (eg, an audio I/O port, a video I/O port), a power unit, and a computing device. can

Wireless devices

100 and 200 include, but are not limited to, a robot (100a in FIG. 1 ), a vehicle (100b-1 and 100b-2 in FIG. 1 ), an XR device (100c in FIG. 1 ), a portable device ( FIG. 1 100d), home appliances (100e in FIG. 1), IoT devices (100f in FIG. 1), digital broadcasting terminals, hologram devices, public safety devices, MTC devices, medical devices, fintech devices (or financial devices), security devices , climate/environment device, AI server/device (400 in FIG. 1), base station (200 in FIG. 1), and may be implemented in the form of a network node. The

wireless devices

100 and 200 may be used in a mobile or fixed location depending on usage/service.

In FIG. 3 , all of the various components, devices/parts and/or modules of the

wireless devices

100 and 200 may be connected to each other through wired interfaces, or at least some of them may be wirelessly connected through the communication device 110. For example, in each of the

wireless devices

100 and 200, the control device 120 and the communication device 110 are connected by wire, and the control device 120 and the first devices (eg, 130 and 140) are communication devices. It can be connected wirelessly through (110). Each component, device/portion and/or module within the

wireless device

100, 200 may further include one or more elements. For example, the control device 120 may be configured by one or more processor sets. For example, the control device 120 may be configured by a set of a communication control processor, an application processor (AP), an electronic control unit (ECU), a graphic processing unit, and a memory control processor. As another example, the memory device 130 may include RAM, dynamic RAM (DRAM), ROM, flash memory, volatile memory, non-volatile memory, and/or a combination thereof.

Referring to FIG. 4 , a UE 100 may correspond to the first wireless device 100 of FIG. 2 and/or the

wireless device

100 or 200 of FIG. 3 .

The UE 100 includes a processor 102, a memory 104, a transceiver 106, one or more antennas 108, a power management module 141, a battery 142, a display 143, a keypad 144, a SIM It includes a (Subscriber Identification Module) card 145, a speaker 146, and a microphone 147.

Processor 102 may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flow diagrams disclosed herein. Processor 102 may be configured to control one or more other components of UE 100 to implement the descriptions, functions, procedures, proposals, methods and/or operational flow diagrams disclosed herein. Layers of air interface protocols may be implemented in processor 102 . Processor 102 may include an ASIC, other chipset, logic circuit, and/or data processing device. Processor 102 may be an applications processor. The processor 102 may include at least one of a DSP, a central processing unit (CPU), a graphics processing unit (GPU), and a modem (modulator and demodulator). Examples of processor 102 are SNAPDRAGON ^TM series processors made by Qualcomm®, EXYNOS ^TM series processors made by Samsung®, A series processors made by Apple®, HELIO ^TM series processors made by MediaTek®, and ATOM ^TM series processors made by Intel®. Or it can be found in the corresponding next-generation processors.

Memory 104 is operatively coupled to processor 102 and stores various information for operating processor 102 . Memory 104 may include ROM, RAM, flash memory, memory cards, storage media, and/or other storage devices. When implementation is implemented in software, the techniques described herein may be implemented using modules (eg, procedures, functions, etc.) that perform the descriptions, functions, procedures, suggestions, methods, and/or operational flow diagrams disclosed herein. there is. A module may be stored in memory 104 and executed by processor 102 . Memory 104 may be implemented within processor 102 or external to processor 102, in which case it may be communicatively coupled with processor 102 through a variety of methods known in the art.

A transceiver 106 is operatively coupled to the processor 102 and transmits and/or receives wireless signals. The transceiver 106 includes a transmitter and a receiver. The transceiver 106 may include baseband circuitry for processing radio frequency signals. The transceiver 106 controls one or more antennas 108 to transmit and/or receive radio signals.

Power management module 141 manages power of processor 102 and/or transceiver 106 . The battery 142 supplies power to the power management module 141 .

The display 143 outputs the result processed by the processor 102. Keypad 144 receives input for use by processor 102 . A keypad 144 may be displayed on the display 143 .

The SIM card 145 is an integrated circuit for safely storing IMSI (International Mobile Subscriber Identity) and a related key, and is used to identify and authenticate a subscriber in a mobile phone device such as a mobile phone or computer. You can also store contact information on many SIM cards.

The speaker 146 outputs sound related results processed by the processor 102 . Microphone 147 receives sound related input for use by processor 102 .

Noise Shaping (NS) will be described.

NS is part of the process of quantization or bit-depth reduction of digital signals, and is a technique commonly used in digital audio, image and video processing. The purpose of this technique is to increase the apparent Signal-to-Noise Ratio (SNR) of the resulting signal. This is done by changing the spectral shape of the error caused by dithering and quantization. Accordingly, noise power may be at a lower level in frequency bands where noise is considered less desirable and at a relatively higher level in bands where noise is considered more desirable.

An example of an NS structure conventionally used in a wireless communication system is an analog-to-digital converter (ADC)-based delta-sigma modulation technique. This is a concept of oversampling in the time domain. In signal processing, oversampling is the process of sampling a signal with more than twice the bandwidth or the highest sampling frequency that can be sampled, which is effective in reducing noise. By performing oversampling in the time domain, noise density can be reduced by increasing the entire band of the signal, and noise power in the signal domain can be reduced through a low-pass filter.

Meanwhile, in the 6G system, a terahertz (THz) band or a sub-terahertz (sub-THz) band of 100 GHz or more may be used. Since a sampling rate is already very high in a terahertz band or sub-terahertz band wireless communication system, it may be difficult to perform NS through oversampling in the time domain.

Therefore, in a terahertz band or sub-terahertz band wireless communication system, it may be considered to perform NS using oversampling in the spatial domain. In a terahertz band or sub-terahertz band wireless communication system, it is expected that the number of antennas is very large by using a massive array antenna, so the antenna is used as a resource.

More specifically, in the existing wireless communication system, antennas are installed for every half wavelength (λ/2), but for oversampling in the spatial domain, antennas may be arranged for half wavelengths or less. For example, if the oversampling coefficient/number is K _u , the antenna spacing is λ/2K _u . From the perspective of spatial-temporal Regions of Support (RoS), the receivable signal region is maximized when the antenna is placed in half-wavelength units, and when the antenna is additionally placed by oversampling in the spatial domain, As RoS is reduced, the sum of noise power in the entire receive area may be reduced. Oversampling in the spatial domain is applicable to both ADCs and low-noise amplifiers (LNAs).

5 shows an example of a unit structure for performing NS to which the implementation of the present specification is applied. 6 shows an example of an ideal noise transfer function (NTF) when NS is performed according to a unit structure to which the implementation of the present specification is applied.

Referring to FIG. 5 , a received signal having a unit structure for performing NS may be expressed by Equation 1 below, and thus NTF (1-z ^-1 ) corresponds to FIG. 6 . Referring to FIG. 6, in an ideal case, there is a section in which the NTF becomes 0.

[Equation 1]

In the unit structure of FIG. 5 , the i-th received signal y _i considers only the signal received from the adjacent antenna w _i−1 without considering the signal received from another antenna. However, in order to actually do this, it is necessary to cut off the signal received below the antenna w _i-2 . Since the i−1 th received signal y _i ₋₁ uses the signal received at the antenna w−2, as a result, the i th received signal y _i has noise less than or equal to that of the antenna w−2.

7 shows an example of a continuous structure for performing NS to which the implementation of the present specification is applied. 8 shows an example of NTF when performing NS according to a contiguous structure to which the implementation of the present specification is applied.

In order for all antennas to obtain the NS effect, signals received from all antennas must be used, and for this, a cascade structure in which unit structures described in FIG. 5 are continuously connected is required. By continuously connecting the unit structures, LNAs can be continuously connected. The received signal of the continuous structure of FIG. 7 may be expressed by Equation 2, and NTF (1/(1+z ^-1 )) corresponding to this corresponds to FIG. 8 . Referring to FIG. 7 , it can be seen that the first received signal y ₁ continuously affects subsequent received signals in a continuous form. Referring to FIG. 8 , unlike the case of performing NS according to the unit structure (see FIG. 6 ), it can be seen that the minimum value of NTF is 0.5 when performing NS according to the continuous structure. That is, when NS is performed by continuously connecting unit structures, the NS effect is greatly reduced.

[Equation 2]

On the other hand, the NTF described in FIG. 8 has the following problems.

(1) Trade-off by offer sampling

The NTF of FIG. 8 corresponds to an ideal NTF that does not consider noise attenuation performance according to a direction of arrival (DoA) of an actual received signal.

However, if antennas are actually oversampled and deployed, mutual coupling between antennas may occur, resulting in loss of signals and, as a result, deterioration in beamforming performance. Referring to FIG. 9 , it can be seen that the SINR decreases as the distance between antennas decreases. That is, when the antenna is oversampled and arranged, the effect of noise shaping and the deterioration of beamforming performance are in a trade-off relationship with each other. Therefore, it is necessary to simultaneously consider the effect of noise shaping and the mutual coupling effect according to the operand sampling of the antenna.

(2) Performance analysis according to the number of antennas

The NTF of FIG. 8 corresponds to an ideal NTF assuming that the number of antennas is infinite. However, the number of actual antennas is finite and may also be arranged based on a sub-array. That is, NTF analysis is required in a continuous structure of an antenna that can be actually implemented, but the NTF of FIG. 8 has limitations in showing actual performance.

Accordingly, the present specification analyzes the mutual coupling effect and the NS effect according to the reception beamforming structure in consideration of the oversampling of the antenna and the DoA of the reception signal in the spatial domain, and provides a method for maximizing the SNR after reception beamforming do. More specifically, the following two methods may be provided according to the implementation of the present specification. Based on the following two methods, it is possible to obtain an SNR gain after reception beamforming that is superior to the conventional method based on the DoA of the received signal when mutual coupling is considered.

(1) Performance analysis of NS considering mutual coupling according to the actual antenna connection structure: As described above, in the past, NTF was analyzed in the absence of mutual coupling under the assumption that the unit structure is infinitely connected, but this specification The implementation of provides a method of accurately analyzing the NTF according to the number of antennas and the NS structure of the actual antenna in consideration of the situation in which the antenna is actually deployed.

(2) Receiving end structure changing NS structure according to DoA: The implementation of the present specification analyzes the SNR of reception beamforming according to DoA of a received signal, and provides a receiving end structure that changes according to DoA. In conventional wireless communication systems, signals with various DoAs must be received through multiple paths, so average NS performance is important. expected Accordingly, it may be possible to analyze the SNR of reception beamforming according to the DoA of the reception signal.

The following drawings are made to explain a specific example of the present specification. Since the names of specific devices or names of specific signals/messages/fields described in the drawings are provided as examples, the technical features of the present specification are not limited to the specific names used in the drawings below.

Referring to FIG. 10, according to the implementation of the present specification, a total of M antennas are arranged according to an oversampling coefficient/number K _u in the spatial domain. That is, the distance between each antenna is d=λ/2K _u . It is assumed that DoAs of signals received through M antennas are the same as θ. θ = 0 means that the signal is received perpendicular to the antenna. Mutual coupling may be applied to signals {w1, w2, ..., w _M } received through M antennas. In FIG. 10, w _i is the i th received signal, n _i is the noise of the i th NLA, and y _i is the signal after the i th LNA amplification. A represents the amplification of A in the LNA, and 1/A represents the signal attenuation. The time delay is a passive element for the sampling time of the next antenna when performing NS.

In addition, according to the implementation of the present specification, unit structures corresponding to each of the M antennas are continuously connected to form a continuous structure for performing NS. A variable attenuator may be inserted between unit structures corresponding to each antenna. For example, in FIG. 10 , an attenuator having an α value is inserted into a unit structure corresponding to an odd-numbered antenna, and an attenuator having a β value is inserted into a unit structure corresponding to an even-numbered antenna. However, this is just an example for convenience of analysis, and the value of the attenuator inserted between the unit structures corresponding to each antenna may be variously changed.

At step S1100, the method includes performing an initial connection with a network.

At step S1110, the method includes receiving signals through a plurality of antennas.

In some implementations, the plurality of antennas may be arranged based on a one-dimensional array antenna structure and/or a two-dimensional array antenna structure.

In step S1120, the method includes determining a relationship between DoA and SNR according to a change in the number of oversampling and the attenuator.

At step S1130, the method includes estimating the DoA of the received signal.

In step S1140, the method includes selecting a first receiver structure or a second receiver structure that maximizes the SNR based on the estimated DoA.

In some implementations, the first receiver structure is selected based on that the estimated DoA is within a specific angle (eg, -10 degrees to 10 degrees) based on 0 degrees, and the first receiver structure is TS (Two Source ) structure. In the TS structure, a value of an attenuator connected to a first antenna among the plurality of antennas may be 1, and a value of an attenuator connected to a second antenna adjacent to the first antenna may be 0. In this case, the first antenna may be used for NS, and the second antenna may be used for beamforming.

In some implementations, the second receiver structure is selected based on that the estimated DoA is other than a specific angle (eg, >10 degrees or <-10 degrees) relative to 0 degrees, and the second receiver structure is CS ( Cascade Source) structure. In the CS structure, a value of an attenuator connected to a first antenna among the plurality of antennas may be the same as a value of an attenuator connected to a second antenna adjacent to the first antenna.

In step S1150, the method includes processing the received signal based on the selected receiver structure.

In addition, the method described from the perspective of the UE in FIG. 11 is performed by the first wireless device 100 shown in FIG. 2, the wireless device 100 shown in FIG. 3, and/or the UE 100 shown in FIG. can be performed

More specifically, a UE includes a plurality of antennas, one or more processors, and one or more memories operatively connectable to the one or more processors. The one or more memories store instructions that cause the next operation to be performed by the one or more processors.

The UE performs an initial connection with the network.

The UE receives signals through a plurality of antennas.

The UE determines the relationship between DoA and SNR according to the number of oversampling and changes in the attenuator.

The UE estimates the DoA of the received signal.

Based on the estimated DoA, the UE selects either the first receiver structure or the second receiver structure that maximizes the SNR.

The UE processes the received signal based on the selected receiver structure.

In addition, the method described from the perspective of the UE in FIG. 11 is the control of the processor 102 included in the first wireless device 100 shown in FIG. 2, the communication device included in the wireless device 100 shown in FIG. 110 and/or control of the control device 120 and/or control of the processor 102 included in the UE 100 shown in FIG. 4 .

More specifically, a processing device operating in a wireless communication system includes one or more processors and one or more memories operably connectable with the one or more processors. The one or more processors performing an initial connection with a network; Determining a relationship between DoA and SNR according to a change in oversampling number and attenuator; estimating a DoA of a received signal; selecting one of a first receiver structure and a second receiver structure that maximizes the SNR based on the estimated DoA; and processing the received signal based on the selected receiver structure.

Also, the method described from the perspective of the UE in FIG. 11 can be performed by the software code 105 stored in the memory 104 included in the first wireless device 100 shown in FIG. 2 .

The technical features herein may be implemented directly in hardware, in software executed by a processor, or in a combination of the two. For example, a method performed by a wireless device in wireless communication may be implemented in hardware, software, firmware, or a combination thereof. For example, the software may be in RAM, flash memory, ROM, EPROM, EEPROM, registers, hard disk, a removable disk, a CD-ROM, or other storage medium.

Some instances of storage media may be coupled to the processor such that the processor may read information from the storage media. Alternatively, the storage medium may be integrated into the processor. The processor and storage medium may be in an ASIC. In other examples, the processor and storage medium may exist as separate components.

Computer readable media may include tangible, non-transitory computer readable storage media.

For example, non-transitory computer readable media may include RAM such as synchronous dynamic RAM (SDRAM), ROM, non-volatile RAM (NVRAM), EEPROM, flash memory, magnetic or optical data storage media, or instructions or data structures. It may include other media that can be used to store. A non-transitory computer readable medium may include any combination of the above.

Further, the methods described herein may be realized, at least in part, by a computer readable communication medium that carries or communicates code in the form of instructions or data structures and which a computer can access, read and/or execute.

According to some implementations herein, a non-transitory computer-readable medium (CRM) stores a plurality of instructions.

More specifically, the CRM stores instructions that cause operations to be performed by one or more processors. The operation may include performing an initial connection with a network; Determining a relationship between DoA and SNR according to a change in oversampling number and attenuator; estimating a DoA of a received signal; selecting one of a first receiver structure and a second receiver structure that maximizes the SNR based on the estimated DoA; and processing the received signal based on the selected receiver structure.

Hereinafter, various implementations of the present specification are described. In particular, in each of the CS structure and the TS structure described in FIG. 11, mutual coupling, DoA of the received signal, and SNR analysis according to the attenuator value are described. In order to accurately estimate/calculate the receive beamforming SNR gain, a mutual coupling is applied, and the coupling matrix Γ can be given by Equation 3.

[Equation 3]

In Equation 3, Z _L is the load impedance, Z _A is the antenna impedance, and Z is a mutual impedance matrix, which can be calculated or measured according to the antenna structure.

The CS structure described in FIG. 12 assumes that the value α=β of the attenuator in the system illustrated in FIG. 10 . Assuming that all attenuators have the same value of α, the received signal at the k-th antenna can be expressed by Equation 4.

[Equation 4]

in Equation 4

is the beamforming weight value,

is a variable including oversampling.

A signal after reception beamforming can be expressed by Equation 5.

[Equation 5]

The power of the received signal can be expressed by Equation (6).

[Equation 6]

Noise power can be expressed as Equation 7.

[Equation 7]

The TS structure described in FIG. 13 assumes that the attenuator values α=1 and β=0 in the system illustrated in FIG. 10 . In order to make the TS structure of FIG. 13 from the CS structure of FIG. 12, some of the antennas are used only for NS, and the remaining antennas not used for NS can be used for beamforming. For example, odd-numbered antennas may be used for NS, and even-numbered antennas may be used for beamforming. As described in FIG. 13, this can be implemented by setting the value α=1 of the attenuator inserted into the odd-numbered antenna and the value β=0 of the attenuator inserted into the odd-numbered antenna. Accordingly, antenna 1 and antenna 2 are continuously connected, antenna 3 and antenna 4 are continuously connected, and antenna 2 and antenna 3 are disconnected without being connected.

A received signal at an even-numbered antenna can be expressed by Equation 8.

[Equation 8]

This result is the same as that described in Equation 2, but since only even-numbered antennas are used for beamforming, the number of oversampling is reduced by 2 times and the beamforming gain is reduced by 3 dB.

A signal after reception beamforming can be expressed by Equation 9.

[Equation 9]

The power of the received signal can be expressed by Equation 10.

[Equation 10]

Noise power can be expressed as Equation 11.

[Equation 11]

In FIG. 14, when the size of the antenna is fixed to 4λ and α = β = 1 in the CS structure and α = 1 and β = 0 in the TS structure, the CS structure described in FIG. 12 and the TS described in FIG. 13 The noise power reduction performance of the structures is compared. Noise power = 1 is the noise power when NS is not performed. Kx is the number of oversampling at the receiving end. That is, when Kx=1, antennas are arranged at intervals of λ/2, so that a total of 8 antennas are arranged. In the case of Kx=2, antennas are arranged at intervals of λ/4, and a total of 16 antennas are arranged.

Referring to FIG. 14, it can be seen that when the structure of the receiving terminal is the TS structure, the noise power increases rapidly as the DoA increases. In addition, when the structure of the receiving terminal is the CS structure, when the number of oversampling is greater than 2, it can be seen that there is no significant change in noise power even if the DoA is changed.

In FIG. 15, when the size of the antenna is fixed and α = β = 0.95 in the CS structure and α = 1 and β = 0 in the TS structure, the CS structure described in FIG. 12 and the TS structure described in FIG. 13 Noise power reduction performance is compared.

Referring to FIG. 15 , as in FIG. 14 , when the structure of the receiving end is a TS structure, it can be seen that noise power increases rapidly as DoA increases. In addition, when the structure of the receiving terminal is the CS structure, when the number of oversampling is greater than 2, it can be seen that there is no significant change in noise power even if the DoA is changed. In addition, since the noise is continuously attenuated in the CS structure and the noise power gradually decreases, the noise of the antenna far from the receiving antenna has less effect, and as a result, it can be seen that the noise power reduction performance improves from 0.5 to 0.3. there is.

In FIG. 16, when the size of the antenna is fixed to 4λ and α = β = 0.95 in the CS structure and α = 1 and β = 0 in the TS structure, the CS structure described in FIG. 12 and the TS described in FIG. 13 The beamforming SNR gain performance of the structures is compared.

Referring to FIG. 16 , it can be seen that the TS structure shows better beamforming SNR gain performance when DoA is low, and the CS structure shows more stable beamforming SNR gain performance when DoA is large.

Using a result of comparing the beamforming SNR gain performance of the CS structure and the TS structure of FIG. 16, either the CS structure or the TS structure can be used as the structure of the receiving end according to the DoA of the received signal. For example, if the number of oversampling Kx=2 according to the DoA of the received signal, the TS structure uses Kx=1 (because only even-numbered antennas are used for beamforming) and the CS structure uses Kx=2. can

In FIG. 17, it is assumed that 32 dipole antennas, that is, a total of 64 antennas are disposed according to a ULA (uniform linear array) structure. Referring to FIG. 17, when DoA is between -10 degrees and 10 degrees, the TS structure with Kx = 1 shows better beamforming SNR gain performance, and when DoA is less than -10 degrees or greater than 10 degrees, Kx It can be seen that the CS structure with = 2 shows better beamforming SNR gain performance than the TS structure with Kx = 1.

Therefore, if the DoA of the received signal is between -10 degrees and 10 degrees, the received signal can be processed by selecting/using the TS structure of Kx=1, α<1, and β=0 as the structure of the receiving end. If the DoA of the received signal is less than -10 degrees or greater than 10 degrees, a CS structure in which Kx=2 and α=β<1 can be used as the structure of the receiving end. At this time, the values of α and β may be selected/determined according to the structure in which the antennas are arranged.

18 shows an example of a CS structure of a 2D array antenna to which the implementation of the present specification is applied. 19 shows an example of a TS structure of a 2D array antenna to which the implementation of the present specification is applied.

In addition to the one-dimensional array antenna structure, the NS structure according to the implementation of the present specification may be applied to a two-dimensional array antenna structure or an antenna arrangement of various structures. A variable attenuator may be inserted between all antennas, and after estimating the reception beamforming SNR performance according to the DoA as described above, a receiving end structure capable of maximizing the beamforming SNR performance according to the DoA of the received signal may be selected. .

When DoA is larger than a specific value, the CS structure is expected to be advantageous. Accordingly, all antennas of the two-dimensional array can be connected. In FIG. 14, NS represents an RF element including an antenna and an NS structure.

On the other hand, when DoA is smaller than a specific value, it is predicted that a method of connecting only a small number of subarrays to the NS structure similar to the TS structure will be advantageous. When the DoA is small, the size of the subarray may be selected/determined according to estimation of Rx beamforming SNR performance.

This specification may have various effects.

For example, in a massive array antenna structure in which a large number of antennas are disposed, noise of an LNA having high directivity can be effectively reduced.

The claims set forth herein can be combined in a variety of ways. For example, the technical features of the method claims of this specification may be combined to be implemented as a device, and the technical features of the device claims of this specification may be combined to be implemented as a method. In addition, the technical features of the method claims of the present specification and the technical features of the device claims may be combined to be implemented as a device, and the technical features of the method claims of the present specification and the technical features of the device claims may be combined to be implemented as a method. Other implementations are within the scope of the following claims.

Claims

In a method performed by a user equipment (UE) in a wireless communication system,

performing an initial connection with a network;

Receiving signals through a plurality of antennas;

Determining a relationship between a direction of arrival (DoA) and a signal-to-noise ratio (SNR) according to a change in the number of oversampling and an attenuator;

estimating a DoA of the received signal;

selecting one of a first receiver structure and a second receiver structure that maximizes the SNR based on the estimated DoA; and

and processing the received signal based on the selected receiver structure.
According to claim 1,

The first receiver structure is selected based on the fact that the estimated DoA is within a specific angle based on 0 degrees,

The first receiver structure is characterized in that the TS (Two Source) structure.
According to claim 2,

In the TS structure, a value of an attenuator connected to a first antenna among the plurality of antennas is 1, and a value of an attenuator connected to a second antenna adjacent to the first antenna is 0.
According to claim 3,

The first antenna is used for noise shaping (NS),

Wherein the second antenna is used for beamforming.
According to claim 1,

The second receiver structure is selected based on that the estimated DoA is other than a specific angle based on 0 degrees,

Wherein the second receiver structure is a CS (Cascade Source) structure.
According to claim 5,

In the CS structure, a value of an attenuator connected to a first antenna among the plurality of antennas and a value of an attenuator connected to a second antenna adjacent to the first antenna are the same.
According to claim 1,

The plurality of antennas are arranged based on a one-dimensional array antenna structure and / or a two-dimensional array antenna structure.
In a user equipment (UE) operating in a wireless communication system,

multiple antennas;

one or more processors; and

one or more memories operably connectable with the one or more processors;

The one or more memories,

performing an initial connection with a network;

receiving signals through the plurality of antennas;

Determining a relationship between a direction of arrival (DoA) and a signal-to-noise ratio (SNR) according to a change in the number of oversampling and an attenuator;

estimating a DoA of the received signal;

selecting one of a first receiver structure and a second receiver structure that maximizes the SNR based on the estimated DoA; and

processing the received signal based on the selected receiver structure;

Characterized in that for storing instructions for the operation including the to be performed by the one or more processors.
According to claim 8,

The first receiver structure is selected based on the fact that the estimated DoA is within a specific angle based on 0 degrees,

The first receiver structure is a TS (Two Source) structure, characterized in that the UE.
According to claim 9,

In the TS structure, a value of an attenuator connected to a first antenna among the plurality of antennas is 1, and a value of an attenuator connected to a second antenna adjacent to the first antenna is 0.
According to claim 10,

The first antenna is used for noise shaping (NS),

The UE, characterized in that the second antenna is used for beamforming.
According to claim 8,

The second receiver structure is selected based on that the estimated DoA is other than a specific angle based on 0 degrees,

The second receiver structure is a CS (Cascade Source) structure, characterized in that the UE.
According to claim 12,

In the CS structure, a value of an attenuator connected to a first antenna among the plurality of antennas and a value of an attenuator connected to a second antenna adjacent to the first antenna are the same.
According to claim 8,

The plurality of antennas are arranged based on a one-dimensional array antenna structure and / or a two-dimensional array antenna structure.
A processing device operating in a wireless communication system, comprising:

one or more processors; and

one or more memories operably connectable with the one or more processors;

The one or more processors:

performing an initial connection with a network;

Determining a relationship between a direction of arrival (DoA) and a signal-to-noise ratio (SNR) according to a change in the number of oversampling and an attenuator;

estimating a DoA of a received signal;

Based on the estimated DoA, selecting one of a first receiver structure and a second receiver structure that maximizes the SNR; and

processing the received signal based on the selected receiver structure;

A processing device, characterized in that configured to perform an operation comprising a.
In a CRM (computer readable medium) storing instructions for an operation to be performed by one or more processors, the operation comprises:

performing an initial connection with a network;

Determining a relationship between a direction of arrival (DoA) and a signal-to-noise ratio (SNR) according to a change in the number of oversampling and an attenuator;

estimating a DoA of a received signal;

Based on the estimated DoA, selecting one of a first receiver structure and a second receiver structure that maximizes the SNR; and

processing the received signal based on the selected receiver structure;

CRM comprising a.