CN117296434A

CN117296434A - Method for transmitting and receiving signal in unauthorized band and apparatus therefor

Info

Publication number: CN117296434A
Application number: CN202280033872.0A
Authority: CN
Inventors: 明世昶; 梁锡喆; 金善旭
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2021-05-10
Filing date: 2022-05-03
Publication date: 2023-12-26

Abstract

The present disclosure discloses a method for a terminal to transmit an Uplink (UL) signal in a wireless communication system. Specifically, the method comprises the following steps: determining an Energy Detection (ED) threshold based on a maximum Effective Isotropic Radiated Power (EIRP) among at least a portion of the first EIRP for the at least one first UL signal; acquiring channel occupancy based on the ED threshold; and within the channel occupancy, (i) transmitting at least one first UL signal based on each of at least a portion of the first EIRP for each of the at least one first UL signals, and (ii) transmitting a second UL signal based on a second EIRP, wherein the second EIRP may be less than or equal to the maximum EIRP.

Description

Method for transmitting and receiving signal in unauthorized band and apparatus therefor

Technical Field

The present disclosure relates to a method of transmitting and receiving signals in an unlicensed band and an apparatus thereof, and more particularly, to a method of determining one or more Energy Detection (ED) thresholds to transmit and receive signals through one or more Tx beams in an unlicensed band and performing Listen Before Talk (LBT) and an apparatus thereof.

Background

As more and more communication devices require greater communication traffic with current trends, next generation fifth generation (5G) systems are needed to provide enhanced wireless broadband communications as compared to conventional LTE systems. In the next generation 5G system, the communication scenario is divided into enhanced mobile broadband (emmbb), ultra-reliable and low-latency communication (URLLC), large-scale machine type communication (mctc), and the like.

Herein, eMBB is a next generation mobile communication scenario featuring high spectral efficiency, high user experience data rate, and high peak data rate, URLLC is a next generation mobile communication scenario featuring ultra-high reliability, ultra-low latency, and ultra-high availability (e.g., vehicle-to-everything (V2X), emergency services, and remote control), and mctc is a next generation mobile communication scenario featuring low cost, low energy, short packets, and large scale connections (e.g., internet of things (IoT)).

It is an object of the present disclosure to provide a method of transmitting and receiving a signal in an unauthorized band and an apparatus thereof.

Those skilled in the art will appreciate that the objects that can be achieved with the present disclosure are not limited to what has been particularly described hereinabove, and that the above and other objects that can be achieved by the present disclosure will be more clearly understood from the following detailed description.

In one technical aspect of the present disclosure, there is provided a method of transmitting an Uplink (UL) signal by a User Equipment (UE) in a wireless communication system, the method comprising determining an Energy Detection (ED) threshold based on a maximum among at least one first effective isotropic-related power (EIRP) for at least one first UL signal; acquiring channel occupancy based on the ED threshold; and within the channel occupancy, (i) transmitting at least one first UL signal based on each of at least one first EIRP for each of the at least one first UL signals, and (ii) transmitting a second UL signal based on a second EIRP, wherein the second EIRP may be equal to or less than the maximum EIRP.

The second UL signal may not be considered in determining the ED threshold.

The scheduling information for the at least one first UL signal may be received before the scheduling information for the second UL signal is received.

Based on the EIRP for the second UL signal being greater than the maximum EIRP, the second EIRP may be equal to the maximum EIRP.

Channel occupancy may be obtained based on the success of Listen Before Talk (LBT) based on the ED threshold.

The at least one first UL signal and the second UL signal may be transmitted through UL Tx beams different from each other.

The at least one first UL signal and the second UL signal may be transmitted through a frequency band above 52.6 GHz.

In another technical aspect of the present disclosure, there is provided a user equipment for transmitting Uplink (UL) signals in a wireless communication system, the user equipment comprising at least one transceiver, at least one processor, and at least one memory operably connected to the at least one processor and configured to store instructions for enabling the at least one processor to perform operations when executed, wherein the operations may include determining an Energy Detection (ED) threshold based on a maximum EIRP among at least one first effective isotropic-related power (EIRP) for at least one first UL signal; acquiring channel occupancy based on the ED threshold; and within the channel occupancy, (i) transmitting at least one first UL signal based on each of the at least one first EIRP for each of the at least one first UL signals, and (ii) transmitting a second UL signal based on a second EIRP, and wherein the second EIRP may be equal to or less than the maximum EIRP.

The second UL signal may not be considered in determining the ED threshold.

In a further technical aspect of the present disclosure, there is provided an apparatus for transmitting an Uplink (UL) signal in a wireless communication system, the apparatus comprising at least one transceiver, at least one processor, and at least one memory operably connected to the at least one processor and configured to store instructions for enabling the at least one processor to perform operations when executed, wherein the operations may include determining an Energy Detection (ED) threshold based on a maximum EIRP among at least one first effective isotropic-related power (EIRP) for at least one first UL signal; acquiring channel occupancy based on the ED threshold; and within the channel occupancy, (i) transmitting at least one first UL signal based on each of the at least one first EIRP for each of the at least one first UL signals, and (ii) transmitting a second UL signal based on a second EIRP, and wherein the second EIRP may be equal to or less than the maximum EIRP.

In yet another technical aspect of the present disclosure, a computer-readable storage medium is provided, the computer-readable storage medium comprising at least one computer program configured to enable at least one processor to perform operations, wherein the operations may include determining an Energy Detection (ED) threshold based on a maximum EIRP among at least one first effective isotropic-related power (EIRP) for at least one first UL signal; acquiring channel occupancy based on the ED threshold; and within the channel occupancy, (i) transmitting at least one first UL signal based on each of the at least one first EIRP for each of the at least one first UL signals, and (ii) transmitting a second UL signal based on a second EIRP, and wherein the second EIRP may be equal to or less than the maximum EIRP.

In accordance with the present disclosure, to overcome relatively large path loss in the high frequency band of 52.6GHz or higher, an appropriate ED threshold may be set for directional LBT (D-LBT), where a base station and/or user equipment performs Listen Before Talk (LBT) in a particular beam direction by techniques such as analog beamforming using multiple antennas.

In addition, an appropriate D-LBT method and an appropriate ED threshold may be set for DL/UL beams transmitted in a multiplexed manner or DL/UL handover beams in different directions within a COT successfully acquired by D-LBT.

In addition, when beams in different directions are multiplexed within the acquired COT, the power of the signal can be effectively controlled so as not to cause interference to RATs other than NR.

Those skilled in the art will recognize that the effects that can be achieved with the present disclosure are not limited to what has been particularly described hereinabove, and that other advantages of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings.

Drawings

Fig. 1 illustrates a radio frame structure.

Fig. 2 illustrates a resource grid of time slots.

Fig. 3 illustrates an exemplary Uplink (UL) transmission operation of a User Equipment (UE).

Fig. 4 illustrates a wireless communication system supporting unlicensed bands.

Fig. 5 illustrates an exemplary method of occupying resources in an unlicensed band.

Fig. 6 illustrates an exemplary channel access procedure applicable to a UE of the present disclosure for UL and/or DL signaling in an unlicensed band.

Fig. 7 is a diagram illustrating a plurality of listen before talk subbands (LBT-SB) suitable for use in the present disclosure.

Fig. 8 is a diagram illustrating analog beamforming in an NR system.

Fig. 9 is a diagram illustrating beam-based LBT and group-based LBT according to an embodiment of the present disclosure.

Fig. 10 is a diagram illustrating a problem that occurs when performing beam-based LBT according to an embodiment of the present disclosure.

Fig. 11 to 13 are diagrams illustrating an overall operation procedure for transmitting and receiving uplink signals by a user equipment and a base station according to an embodiment of the present disclosure.

Fig. 14 to 16 are diagrams illustrating an overall operation procedure for transmitting and receiving downlink signals by a user equipment and a base station according to an embodiment of the present disclosure.

Fig. 17 is a diagram illustrating a method of transmitting and receiving uplink signals within one Channel Occupation Time (COT) according to an embodiment of the present disclosure.

Fig. 18 illustrates an exemplary communication system applied to the present disclosure.

Fig. 19 illustrates an exemplary wireless device suitable for use with the present disclosure.

Fig. 20 illustrates an exemplary vehicle or autonomous driving vehicle suitable for use with the present disclosure.

Detailed Description

The techniques described below may be used in various wireless access systems such as 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 so on. CDMA may be implemented as a radio technology such as Universal Terrestrial Radio Access (UTRA) or CDMA 2000. TDMA may be implemented as a wireless technology such as global system for mobile communications (GSM)/General Packet Radio Service (GPRS)/enhanced data rates for GSM evolution (EDGE). OFDMA may be implemented as a radio technology such as Institute of Electrical and Electronics Engineers (IEEE) 802.11 (wireless fidelity (Wi-Fi)), IEEE 802.16 (worldwide interoperability for microwave access (WiMAX)), IEEE 802.20, evolved UTRA (E-UTRA), and so forth. UTRA is part of Universal Mobile Telecommunications System (UMTS). The third generation partnership project (3 GPP) Long Term Evolution (LTE) is part of evolved UMTS (E-UMTS) using E-UTRA, and LTE-advanced (LTE-A) is an evolution of 3GPP LTE. The 3GPP new radio or new radio access technology (NR) is an evolved version of 3GPP LTE/LTE-A.

Although the following description is given in the context of a 3GPP communication system (e.g., NR) for clarity, the technical spirit of the present disclosure is not limited to the 3GPP communication system. For background, terms and abbreviations used in the present disclosure refer to technical specifications (e.g., 38.211, 38.212, 38.213, 38.214, 38.300, 38.331, etc.) published prior to the present disclosure.

The following will describe 5G communication involving a new radio access technology (NR) system.

Three key areas of requirement for 5G are (1) enhanced mobile broadband (emmbb), (2) large-scale machine type communication (mctc), and (3) ultra-reliable and low-latency communication (URLLC).

Some use cases may require multiple dimensions for optimization, while other use cases may only focus on one Key Performance Indicator (KPI). The 5G supports this diversity of use cases in a flexible and reliable manner.

The eMBB goes far beyond basic mobile internet access and covers rich interworking, media and entertainment applications in the cloud or Augmented Reality (AR). Data is one of the key drivers for 5G, and in the 5G age we might see for the first time that there is no dedicated voice service. In 5G, the intended voice is simply treated as an application using the data connection provided by the communication system. The main driving force for increased traffic is an increase in content size and the number of applications requiring high data rates. Streaming services (audio and video), interactive video and mobile internet connections will continue to be used more widely as more devices connect to the internet. Many of these applications require an always-on connection to push real-time information and notifications to users. Cloud storage and applications are rapidly increasing for mobile communication platforms. This applies both to work and entertainment. Cloud storage is a specific use case that drives the increase in uplink data rates. 5G will also be used for remote work in the cloud, which requires much lower end-to-end delay when done using a haptic interface in order to maintain a good user experience. Entertainment (e.g., cloud gaming and video streaming) is another key driving force for increased mobile broadband capacity demand. Entertainment is very important on smart phones and tablet computers anywhere, including high mobility environments such as trains, automobiles and airplanes. Another use case is AR and information search for entertainment, which requires very low latency and large amounts of instant data.

One of the most desirable 5G use cases is to actively connect the functions of embedded sensors in each field, i.e. mctc. There are expected to be 204 million potential internet of things (IoT) devices by 2020. In industrial IoT, 5G is one of the areas that play a key role in implementing smart cities, asset tracking, smart utilities, agriculture, and security infrastructure.

URLLC includes services that will change industries using ultra-reliable/available low-latency links, such as remote control of critical infrastructure and autonomous vehicles. Reliability and delay levels are critical to smart grid control, industrial automation, robotics, drone control and coordination, etc.

Now, a plurality of use cases in a 5G communication system including an NR system will be described in detail.

5G may supplement Fiber To The Home (FTTH) and cable-based broadband (or Data Over Cable Service Interface Specification (DOCSIS)) as a means of providing streaming at data rates of hundreds of megabits per second to gigabits per second. Such high speeds are required for television broadcasts with resolutions of 4K (6K, 8K and higher) or higher, and Virtual Reality (VR) and AR. VR and AR applications mainly include immersive motion games. A particular application may require a particular network configuration. For example, for VR games, the gaming establishment may have to integrate the core server with the network operator's edge network server in order to minimize latency.

The automotive industry is expected to become a very important new driving force for 5G, with many use cases for mobile communication of vehicles. For example, passenger entertainment requires a mobile broadband of both high capacity and high mobility, as future users will expect to continue their good quality connections independent of their location and speed. Other examples of uses in the automotive industry are AR dashboards. These displays superimpose information on what the driver sees through the front window, identify objects in the dark and tell the driver the distance and movement of the objects. In the future, wireless modules will enable the exchange of information between the vehicles themselves, between the vehicles and the supporting infrastructure, and between the vehicles and other connected devices (e.g., devices carried by pedestrians). The safety system may guide the driver during alternative actions to allow them to drive more safely and reduce the risk of accidents. The next stage would be to remotely control or automatically drive the vehicle. These require very reliable, very fast communication between different autonomous vehicles and between the vehicle and the infrastructure. In the future, autonomous vehicles will perform all driving activities while drivers focus on traffic anomalies that are elusive to the vehicle itself. The technical need for an autonomous vehicle requires ultra-low delay times and ultra-high reliability, improving traffic safety to levels that are not reachable by people.

Smart cities and smart households (commonly referred to as smart society) will embed dense wireless sensor networks. The distributed network of intelligent sensors will identify the cost of the city or home and the conditions for energy conservation maintenance. A similar arrangement can be made for each home, wherein the temperature sensor, window and heating controller, burglar alarm and home appliance are all connected wirelessly. Many of these sensors are typically characterized by low data rates, low power and low cost, but for example, real-time High Definition (HD) video may be required for monitoring in certain types of devices.

The consumption and distribution of energy (including heat or gas) is becoming highly decentralized, creating the need for automatic control of very distributed sensor networks. Smart grids interconnect these sensors, using digital information and communication technology to collect and act upon the information. The information may include information about the behavior of suppliers and consumers, allowing the smart grid to improve efficiency, reliability, economy, and sustainability of production and distribution of fuels such as electricity in an automated manner. The smart grid may be considered as another sensor network with low latency.

The health sector has many applications that can benefit from mobile communications. The communication system enables telemedicine providing remote clinical healthcare. It helps to eliminate distance obstructions and may improve access to medical services that are not always available in remote rural communities. It is also used to save lives in critical care and emergency situations. Wireless sensor networks based on mobile communications may provide remote monitoring and sensors for parameters such as heart rate and blood pressure.

Wireless and mobile communications are becoming increasingly important for industrial applications. The installation and maintenance of wires is expensive and the possibility of replacing the cable with a reconfigurable wireless link is an attractive opportunity for many industries. However, achieving this requires wireless connections to operate with similar delay, reliability and capacity as the cable, and simplifies its management. Low latency and very low error probability are new requirements that need to be resolved with 5G.

Finally, logistics and shipping tracking are important uses of mobile communications that enable tracking inventory and packages at any time and place through the use of location-based information systems. Logistical and shipment tracking use cases typically require lower data rates but require wide coverage and reliable location information.

Fig. 1 illustrates a radio frame structure.

In NR, UL and DL transmissions are configured in frames. Each radio frame has a length of 10ms and is divided into two 5ms half frames. Each field is divided into five 1ms subframes. The subframe is divided into one or more slots, and the number of slots in the subframe depends on a subcarrier spacing (SCS). Each slot includes 12 or 14 OFDM (a) symbols according to a Cyclic Prefix (CP). When normal CP is used, each slot includes 14 OFDM symbols. When the extended CP is used, each slot includes 12 OFDM symbols. The symbols may include OFDM symbols (or CP-OFDM symbols) and SC-FDMA symbols (or discrete fourier transform spread OFDM (DFT-s-OFDM) symbols).

Table 1 exemplarily illustrates that the number of symbols per slot, the number of slots per frame, and the number of slots per subframe vary according to SCS in the normal CP case.

TABLE 1

SCS(15*2^u)	Nslotsymb	Nframe,uslot	Nsubframe,uslot
				15KHz(u＝0)	14	10	1
30KHz(u＝1)	14	20	2
				60KHz(u＝2)	14	40	4
120KHz(u＝3)	14	80	8
				240KHz(u＝4)	14	160	16

*N ^slot _symb : number of symbols in a slot, N ^frame,u _slot : number of slots in a frame

*N ^subframe,u _slot : number of slots in subframe

Table 2 illustrates that in the case of the extended CP, the number of symbols per slot, the number of slots per frame, and the number of slots per subframe vary according to SCS.

TABLE 2

SCS(15*2^u)	Nslotsymb	Nframe,uslot	Nsubframe,uslot
				60KHz(u＝2)	12	40	4

The frame structure is only one example, and the number of subframes, the number of slots, and the number of symbols in a frame can be changed in various ways. In an NR system, different OFDM (a) parameter sets (e.g., SCS, CP length, etc.) may be configured for a plurality of cells aggregated for one UE. Thus, the (absolute time) duration of a time resource (e.g., a subframe, a slot, or a Transmission Time Interval (TTI)) consisting of the same number of symbols, referred to as a Time Unit (TU) for simplicity, may be configured differently among aggregated cells.

In NR, various parameter sets (or SCS) may be supported to support various fifth generation (5G) services. For example, a wide area in a conventional cellular band can be supported using a 15kHz SCS, while dense urban areas, low latency, and wide carrier bandwidths can be supported using 30kHz or 60kHz SCS. With SCS of 60kHz or higher, bandwidths greater than 24.25kHz can be supported to overcome phase noise.

The NR frequency band can be defined by two types of frequency ranges, FR1 and FR 2. FR1 and FR2 can be configured as described in table 3 below. FR2 may be millimeter wave (mmW).

TABLE 3

Frequency range name	Corresponding frequency range	Subcarrier spacing
			FR1	450MHz-7125MHz	15,30,60kHz
FR2	24250MHz-52600MHz	60,120,240kHz

Fig. 3 illustrates a resource grid during the duration of one slot. A slot includes a plurality of symbols in the time domain. For example, one slot includes 14 symbols in the case of normal CP and 12 symbols in the case of extended CP. The carrier comprises a plurality of subcarriers in the frequency domain. A Resource Block (RB) may be defined by a plurality of (e.g., 12) consecutive subcarriers in the frequency domain. The bandwidth part (BWP) may be defined by a plurality of consecutive (physical) RBs ((P) RBs) in the frequency domain, and corresponds to one parameter set (e.g., SCS, CP length, etc.). The carrier may include up to N (e.g., 5) BWPs. The data communication may be performed in active BWP and only one BWP may be activated for one UE. Each element in the resource grid may be referred to as a Resource Element (RE) to which one complex symbol may be mapped.

Fig. 3 illustrates an exemplary UL transmission operation of a UE. The UE may send the intended packet based on DG (fig. 1 (a)) or CG (fig. 1 (b)).

Resources for CG may be shared among multiple UEs. UL signal transmissions based on CG from each UE may be identified by time/frequency resources and RS parameters (e.g., different cyclic shifts, etc.). Thus, when the UE fails to transmit the UL signal due to a signal collision, the BS may identify the UE and explicitly transmit a retransmission grant for the corresponding TB to the UE.

K duplicate transmissions including an initial transmission are supported for the same TB through the CG. The same HARQ process ID is determined for K repeated UL signals based on the resources used for the initial transmission. The Redundancy Version (RV) of the TB for the K repetitions has one of the patterns {0,2,3,1}, {0,3,0,3} and {0,0 }.

The UE performs repeated transmissions until one of the following conditions is satisfied:

-successfully receiving UL grants for the same TB;

-the number of repetitions of TB reaches K; and

the end time of the period P is reached.

Uplink power control

Pusch (physical uplink shared channel) power control

If the UE transmits PUSCH at active UL BWP b of carrier f of serving cell c using PUSCH power control adjustment status with index l and parameter set configuration with index j, the UE may use the following [ equation 1 ]Determining PUSCH transmission power P at PUSCH transmission occasion i _PUSCH,b,f,c (i,j,q _d ,l)。

[ equation 1]

Here, P _CMAX,f,c (i) Is the maximum output power of carrier f serving cell c in PUSCH transmission occasion i configured for the UE.

In addition, P _{O_PUSCH,b,f,c} (j) Is composed of component P _{O_NOMINAL_PUSCH,f,c} (j) Sum component P _{O_UE_PUSCH,f,c} (j) (whenWhen) and the parameters of the composition.

In this case P _{O_NOMINAL_PUSCH,f,c} (j) And P _{O_UE_PUSCH,f,c} (j) The value of (a) may be different depending on the use of PUSCH (e.g., type-1 random access, type-2 random access, configuration grant, dynamic sequence).

α _b,f,c (j) Is an offset value that compensates for the path loss, and it may also vary depending on the use of PUSCH (e.g., type-1 random access, type-2 random access, configuration grant, dynamic grant).

M _{RB，b，f，c} ^PUSCH (i) Is a bandwidth for PUSCH resource allocation, which is represented by the number of Resource Blocks (RBs) and subcarrier spacing (SCS) of PUSCH transmission occasion i in active UL BWP b of carrier f of serving cell c.

PL _b,f,c (q _d ) Reference signal index q, which is active DL BWP of carrier f of UE using serving cell c _d Downlink path loss estimation in dB.

Δ _{TF，b，f，c} (i) Is a value determined based on the higher layer parameter deltaMCS of the active UL BWP b of carrier f of the serving cell c.

f _b,f,c (i, l) is the PUCH power control adjustment status for PUSCH transmission occasion i and active UL BWP b for carrier f and serving cell c.

Pucch (physical uplink control channel) power control

If the UE transmits PUSCH at active UL BWP b of carrier f of primary cell c using PUCCH power control adjustment state with index l, the UE may use the following [ equation 2]Determining PUCCH transmission power P at PUSCH transmission occasion i _PUCCH,b,f,c (i,q _u ,q _d ,l)。

[ equation 2]

Here, P _{CMAX,f c} (i) Is the maximum output power of carrier f of primary cell c at PUCCH transmission occasion i configured for the UE.

In addition, P _{O_PUCCH,b,f,c} (q _u ) Is composed of component P _{O_NOMINAL_PUCCH} Sum component P _{O_UE_PUCCH} (q _u ) And parameters consisting of the sum of the parameters.

In this case P _{O_PUCCH,b,f c} (q _u ) And P _{O_UE_PUCCH} (q _u ) The value of (c) may vary depending on the value of higher layer signaling and/or the presence or absence of higher layer signaling.

M _RB,b,f,c ^PUCCH (i) Is a bandwidth for PUSCH resource allocation, which is represented by the number of Resource Blocks (RBs) and subcarrier spacing of PUSCH transmission occasion i in active UL BWP b for carrier f of primary cell c.

PL _b,f,c (q _d ) Reference signal index q, which is active DL BWP of carrier f of UE using primary cell c _d Downlink path loss estimation in dB.

Δ _{TF，b，f，c} (i) Is a PUCCH transmission power adjustment component of active DL BWP for carrier f of the primary cell c and may vary according to PUCCH formats.

g _b，f，c (i, l) is a PUCCH transmission power adjustment state of the active DL BWP for the carrier f of the primary cell c, and may vary according to Transmission Power Control (TPC).

3. Sounding Reference Signal (SRS) power control

The UE may allocate the same power to the antenna ports configured for SRS transmission. If the UE transmits SRS on the active UL BWP b of the carrier f of the serving cell c using the SRS power control adjustment state index l, the SRS transmission power in the SRS transmission occasion i may be determined as shown in equation 3.

[ equation 3]

In equation 3, P _CMAX,f,c (i) Representing maximum power output by UE for carrier f of serving cell c in SRS transmission occasion i, and P _{O_SRS,b,f,c} (q _s ) May be based on SRS resource set q for active UL BWP b _s And p ₀ Obtained.

In addition, M _SRS,b,f,c (i) Is the SRS bandwidth expressed in number of RBs for SRS transmission occasion i on active UL BWP b, and α _SRS,b,f,c (q _s ) The set of SRS resources q and alpha of UL BWP that can be derived from carrier f of serving cell c _s Obtained. PL (PL) _b,f,c (q _d ) Is DL pathloss estimation in dB and may be based on RS index q of active DL BWP of the serving cell _d And SRS resource set q _s To calculate. RS index q _d From the SRS resource set q _s The associated higher layer parameter pathassReferenceRS. The UE may obtain the SS/PBCH block index or CSI-RS resource index from the pathloss reference RS. If the UE does not receive the pathloss reference RS, the UE may obtain PL by using an SS/PBCH block index obtained from a Master Information Block (MIB) as an RS resource _b,f,c (q _d )。

In addition, h _b,f,c (i) Can be composed ofDefinition wherein delta _SRS,b,f,c May be determined according to a predetermined table. In addition, delta _SRS,b,f,c (m) may be encoded in association with other Transmit Power Control (TPC) commands included in DCI format 2_3, and +.>The determination may be based on a sum of TPC command values included in a particular TPC command set.

Similar to License Assisted Access (LAA) in conventional 3GPP LTE systems, unlicensed bands are also being considered for cellular communication in 3GPP NR systems. Unlike LAA, independent (SA) operation is targeted in NR cells of unlicensed bands (hereinafter, referred to as NR unlicensed cells (uicells)). For example, PUCCH, PUSCH, and PRACH transmissions may be supported in NR Ucell.

On LAA UL, in case of introducing an asynchronous HARQ process, there is no additional channel for indicating HARQ-ACK information for PUSCH to the UE, such as a Physical HARQ Indicator Channel (PHICH). Thus, it may not be possible to adjust a Contention Window (CW) size in the UL LBT procedure using accurate HARQ-ACK information. In the UL LBT procedure, when a UL grant is received in the nth subframe, the first subframe of the latest UL transmission burst preceding the (n-3) th subframe has been configured as a reference subframe, and the CW size has been adjusted based on a New Data Indicator (NDI) for the HARQ process ID corresponding to the reference subframe. That is, when the BS switches NDI according to one or more Transport Blocks (TBs) or instructs retransmission of one or more TBs, a method has been introduced: the CW size is increased to the next maximum CW size of the currently applied CW size of the set of pre-agreed CW sizes under the assumption that PUSCH transmission fails in the reference subframe due to collision with other signals, or initialized to a minimum value (e.g., CWmin) under the assumption that PUSCH in the reference subframe has been successfully transmitted without collision with other signals.

In NR systems to which various embodiments of the present disclosure are applicable, each Component Carrier (CC) may be allocated/supported up to 400MHz. When a UE operating in such a wideband CC is always operated with a Radio Frequency (RF) module turned on in the entire CC, battery consumption of the UE may increase.

Alternatively, considering various use cases (e.g., eMBB, URLLC, mMTC, etc.) operating within a single wideband CC, different parameter sets (e.g., SCS) may be supported for each frequency band within the CC.

Alternatively, each UE may have a different maximum bandwidth capability.

In this regard, the BS may indicate to the UE to operate in only a portion of the bandwidth of the wideband CC, rather than the entire bandwidth. The partial bandwidth may be defined as a bandwidth part (BWP).

BWP may be a subset of consecutive RBs on the frequency axis. One BWP may correspond to one parameter set (e.g., SCS, CP length, slot/minislot duration, etc.).

Fig. 4 illustrates an exemplary wireless communication system supporting unlicensed bands suitable for use in the present disclosure.

In the following description, a cell operating in a licensed band (L-band) is defined as an L cell, and a carrier of the L cell is defined as a (DL/UL) LCC. A cell operating in an unlicensed band (U-band) is defined as a U-cell, and a carrier of the U-cell is defined as a (DL/UL) UCC. The carrier/carrier frequency of a cell may refer to the operating frequency (e.g., center frequency) of the cell. A cell/carrier (e.g., CC) is commonly referred to as a cell.

When the BS and the UE transmit and receive signals on the carrier aggregated LCCs and UCCs, the LCCs and UCCs may be configured as primary CCs (PCC) and secondary CCs (SCCs), respectively, as shown in fig. 4 (a). The BS and the UE may transmit and receive signals on one UCC or on a plurality of carrier aggregated UCCs, as shown in fig. 4 (b). In other words, the BS and the UE may transmit and receive signals only on the UCC(s) without using any LCCs. For SA operation, PRACH, PUCCH, PUSCH and SRS transmission may be supported on the UCell.

The signaling and receiving operations in the unlicensed band as described in this disclosure may be applied to the deployment scenario described above (unless otherwise noted).

Unless otherwise indicated, the following definitions apply to the following terms used in this disclosure.

-channel: a carrier or a part of a carrier, consisting of a set of consecutive RBs, wherein a Channel Access Procedure (CAP) is performed in a shared spectrum.

-Channel Access Procedure (CAP): evaluating channel availability based on sensing prior to signal transmissionA determination is made as to whether the other communication node(s) is using the channel. The basic sensing unit is of duration T _sl Sensing time slot of=9us. The BS or UE senses the slot during the sensing slot duration. When the power detected in at least 4us within the sensing time slot duration is less than the energy detection threshold X _thresh Time, sense time slot duration T _sl Is considered to be idle. Otherwise, sense time slot duration T _sl Is considered busy. CAP may also be referred to as Listen Before Talk (LBT).

-channel occupancy: transmission(s) on channel(s) from BS/UE after CAP.

Channel Occupation Time (COT): the total time the BS/UE and any BS/UE(s) occupied by the shared channel perform transmission(s) on the channel after the CAP. Regarding the COT determination, if the transmission gap is less than or equal to 25us, the gap duration may be counted in the COT.

The COT may be shared for transmission between the BS and the respective UE(s).

Specifically, sharing UE-initiated COT with a BS may refer to: wherein the UE assigns to the BS a portion of a channel occupied by an LBT (e.g., a class 3 (Cat-3) LBT or a class 4 (Cat-4) LBT) based on a random back-off counter, and when a timing gap occurs before DL transmission starting at the end timing of UL transmission using the UE, performs an operation of DL transmission using the remaining COTs of the UE after performing the LBT (e.g., a class 1 (Cat-1) LBT or a class 2 (Cat-2) LBT) without the random back-off counter, and successfully acknowledging that the channel is idle by the LBT.

Meanwhile, sharing the gNB initiated COT with the UE may refer to: wherein the BS assigns a part of a channel occupied by an LBT (e.g., cat-3 LBT or Cat-4 LBT) based on a random back-off counter to the UE, and when a timing gap occurring before UL transmission starts at a DL transmission end timing using the slave BS, after performing the LBT (e.g., cat-1 LBT or Cat-2 LBT) without the random back-off counter, the UE performs an operation of UL transmission using the remaining COTs of the BS when a successful acknowledgement channel by the LBT is idle.

DL transmission burst: a set of transmissions from the BS without any gaps greater than 16 us. Transmissions from BSs separated by a gap exceeding 16us are considered to be separate DL transmission bursts. The BS may perform the transmission(s) after the gap without sensing channel availability within the DL transmission burst.

UL transmission burst: a set of transmissions from the UE without any gaps greater than 16 us. Transmissions from UEs separated by a gap exceeding 16us are considered separate UL transmission bursts. The UE may perform the transmission(s) after the gap without sensing channel availability within the DL transmission burst.

-discovery burst: DL transmission bursts comprising a set of signal(s) and/or channel(s) confined within a window and associated with a duty cycle. The discovery burst may include BS-initiated transmission(s), including PSS, SSS, and cell-specific RS (CRS), and further include non-zero power CSI-RS. In an NR system, a discovery burst may include BS-initiated transmission(s) including at least SS/PBCH blocks and further including CORESET for scheduling PDCCH of PDSCH carrying SIB1, and/or non-zero power CSI-RS.

Referring to fig. 5, a communication node (e.g., BS or UE) operating in an unlicensed band should determine whether other communication node(s) are using a channel before signal transmission. To this end, the communication node may execute the CAP to access the channel(s) on which the transmission(s) are to be performed in the unlicensed band. The CAP may be performed based on sensing. For example, the communication node may determine, prior to signal transmission, whether other communication node(s) are transmitting signals on the channel(s) through Carrier Sense (CS). Determining that the other communication node(s) are not transmitting signals is defined as confirming Clear Channel Assessment (CCA). Where there is a CCA threshold (e.g., X) that has been predefined or configured by higher layer (e.g., RRC) signaling _thresh ) In the case of (1) when in a channelUpon detecting energy above the CCA threshold, the communication node may determine that the channel is busy. Otherwise, the communication node may determine that the channel is idle. When the channel is determined to be idle, the communication node may begin transmitting signals in the unlicensed band. CAP may be replaced with LBT.

Table 4 depicts exemplary CAPs supported in NR-U.

TABLE 4

In a wireless communication system supporting unlicensed bands, one cell (or carrier (e.g., CC)) or BWP configured for a UE may be a broadband having a larger Bandwidth (BW) than conventional LTE. However, the BW of the required CCA based on independent LBT operation may be limited according to regulations. The Subband (SB) in which LBT is performed alone is defined as LBT-SB. Then, a plurality of LBT-SBs may be included in one broadband cell/BWP. The RB set included in the LBT-SB may be configured through higher layer (e.g., RRC) signaling. Accordingly, one or more LBT-SB may be included in one cell/BWP based on (i) BW of the cell/BWP and (ii) RB set allocation information. Multiple LBT-SBs may be included in the BWP of a cell (or carrier). The LBT-SB may be, for example, the 20-MHz band. The LBT-SB may include a plurality of consecutive (P) RBs in the frequency domain, and thus may be referred to as a (P) RB set.

The UE performs type 1 or type 2CAP for UL signaling in the unlicensed band. In general, the UE may perform CAP (e.g., type 1 or type 2) configured by the BS for UL signal transmission. For example, CAP type indication information may be included in a UL grant (e.g., DCI format 0_0 or DCI format 0_1) that schedules PUSCH transmissions.

In a type 1UL CAP, the length of the time period spanned by the sensing time slot(s) that were sensed as idle prior to transmission(s) is random. The type 1UL CAP may be applied to the following transmission.

PUSCH/SRS transmission(s) scheduled and/or configured by BS

PUCCH transmission(s) scheduled and/or configured by BS

-transmission(s) related to Random Access Procedure (RAP)

Fig. 6 illustrates a type 1CAP suitable for use in the channel access procedure of the UE for UL/DL signaling in the U-band of the present disclosure.

First, UL signal transmission in the U-band will be described with reference to fig. 6.

The UE may be in a deferral duration T _d During the sensing time slot duration in (a), whether the sensing channel is idle. After the counter N is decremented to 0, the UE may perform transmission (S434). The counter N is adjusted by sensing the channel for the additional slot duration(s) according to the following procedure.

Step 1) setting n=n _init Wherein N is _init Is uniformly distributed between 0 and CW _P Random numbers in between, and goes to step 4 (S420).

Step 2) if N >0 and the UE selects the down counter, n=n-1 is set (S440).

Step 3) senses the channel for an additional time slot duration and if the additional time slot duration is idle (Y), go to step 4. Otherwise (N), go to step 5 (S450).

Step 4) if n=0 (Y) (S430), CAP is stopped (S432). Otherwise (N), go to step 2.

Step 5) sensing the channel until the additional delay duration T _d A sensing time slot within which a busy is detected or an additional deferral duration T _d Is sensed as idle (S460).

Step 6) if at the additional deferral duration T _d If the channel is sensed to be idle (Y) for all slot durations, then go to step 4. Otherwise (N), go to step 5 (S470).

Table 5 illustrates m applied to CAP _P The minimum CW, maximum Channel Occupation Time (MCOT), and allowed CW size vary according to channel access priority levels.

TABLE 5

Duration of delay T _d Including m followed by _p Duration T of duration of each successive time slot _f (16 us) in which each time slot has a duration T _sl Is 9us, and T _f Including a sensing time slot duration T at the beginning of a 16-us duration _sl 。CW _Wmin,p <＝CW _p <＝CW _max,p 。CW _p Is set as CW _min,p And may be updated (CW size updated) prior to step 1 based on explicit/implicit received responses to a previous UL burst (e.g., PUSCH). For example CW _p May be initialized to CW based on explicit/implicit received responses to previous UL bursts _min,p May be increased to the next higher allowable value or may be maintained at an existing value.

In a type 2UL CAP, the length of the time period spanned by the sensing time slot(s) that were sensed as idle prior to transmission(s) is deterministic. The type 2UL CAP is classified into a type 2A UL CAP, a type 2B UL CAP, and a type 2C UL CAP. In a type 2A UL CAP, the UE may, for at least a sensing duration T _{short_dl} During (=25us) signals are sent immediately after the channel is sensed as idle. T (T) _{short_DL} Including the duration Tf (=16 us) and an immediately following sensing time slot duration. In type 2A UL CAP, T _f Including the sensing time slot at the beginning of the duration. In a type 2B UL CAP, the UE may sense the time slot duration T _f During (=16us) signals are sent immediately after the channel is sensed as idle. In type 2B UL CAP, T _f Including the sensing time slot within the last 9us of duration. In type 2C UL CAP, the UE does not sense the channel before transmission.

To allow the UE to transmit UL data in the unlicensed band, the BS should succeed in LBT operation to transmit UL grant in the unlicensed band, and the UE should also succeed in LBT operation to transmit UL data. That is, the UE may attempt UL data transmission only when both the BS and the UE succeed in their LBT operations. Further, because a delay of at least 4 milliseconds is involved between UL grant and scheduled UL data in the LTE system, earlier access by another transmission node coexisting in the unlicensed band during this period may defer scheduled UL data transmission by the UE. In this context, a method of improving the efficiency of UL data transmission in an unlicensed band is being discussed.

In order to support UL transmissions with relatively high reliability and relatively low time delay, NR also supports CG type 1 and CG type 2, where BS preconfigure time, frequency and coding resources for UE by higher layer signaling (e.g. RRC signaling) or both higher layer signaling and L1 signaling (e.g. DCI). In the case that no UL grant is received from the BS, the UE may perform UL transmission in the resources configured with type 1 or type 2. In type 1, the periodicity of CG, offset from sfn=0, time/frequency resource allocation, number of repetitions, DMRS parameters, MCS/TB Size (TBs), power control parameters, etc. are configured only by higher layer signaling, such as RRC signaling, and not with L1 signaling. Type 2 is a scheme in which periodicity and power control parameters of CG are configured through higher layer signaling such as RRC signaling, and information about remaining resources (e.g., offset of initial transmission timing, time/frequency resource allocation, DMRS parameters, and MCS/TBS) is indicated by activating DCI as L1 signaling.

The largest difference between the Autonomous Uplink (AUL) of the LTE LAA and the CG of the NR is the HARQ-ACK feedback transmission method for PUSCH transmitted by the UE without receiving UL grant, and the presence or absence of UCI transmitted with PUSCH. Although the HARQ process is determined by an equation of a symbol index, a symbol period, and the number of HARQ processes in CG of NR, explicit HARQ-ACK feedback information is transmitted in AUL downlink feedback information (AUL-DFI) in LTE LAA. Further, in LTE LAA, UCI including information such as HARQ ID, NDI, and RV is also transmitted in AUL UCI whenever AUL PUSCH transmission is performed. In case of CG of NR, the BS identifies the UE through time/frequency resources and DMRS resources for PUSCH transmission, and in case of LTE LAA, the BS identifies the UE through UE ID explicitly included in AUL UCI transmitted together with PUSCH and DMRS resources.

The DL signal transmission in the U-band will now be described with reference to fig. 6.

The BS may perform one of the following U-band access procedures (e.g., channel Access Procedure (CAP)) to transmit DL signals in the U-band.

(1) Type 1DL CAP method

In a type 1DL CAP, the length of the duration spanned by the sensing time slot(s) that were sensed as idle prior to transmission(s) is random. The type 1DL CAP may be applied to the following transmissions:

- (i) BS-initiated transmission(s) comprising (i) a unicast PDSCH with user plane data, or (ii) a unicast PDSCH with user plane data and a unicast PDCCH scheduling user plane data; or alternatively

-BS-initiated transmission(s) comprising (i) discovery bursts only or (ii) discovery bursts multiplexed with non-unicast information.

Referring to fig. 6, the bs may first sense whether the channel is idle for a sensing time slot duration of a deferral duration Td. Next, if the counter N is decremented to 0, transmission may be performed (S434). The counter N is adjusted by sensing the channel for the additional slot duration(s) according to the following procedure.

Step 1) sets n=ninit, where Ninit is a random number uniformly distributed between 0 and CWp, and goes to step 4 (S420).

Step 2) if N >0 and BS selects the down counter, n=n-1 is set (S440).

Step 4) if n=0 (Y), CAP is stopped (S1232). Otherwise (N), go to step 2 (S430).

Step 5) senses the channel until a busy sensing time slot is detected within the additional deferral duration Td or all time slots of the additional deferral duration Td are sensed as idle (S460).

Step 6) if the channel is sensed to be idle (Y) for all slot durations of the additional deferral duration Td, then go to step 4. Otherwise (N), go to step 5 (S470).

Table 6 illustrates that mp, minimum CW, maximum CW, MCOT, and allowed CW sizes applied to CAPs vary according to channel access priority levels.

TABLE 6

The deferral duration Td comprises a duration Tf (16 mus) followed by mp consecutive sense slot durations, wherein each sense slot duration Tsl is 9 mus and Tf comprises the sense slot duration Tsl at the beginning of the 16 mus duration.

CWmin, p < = CWp < =cwmax, p. CWp is set to CWmin, p, and may be updated (CW size update) prior to step 1 based on HARQ-ACK feedback (e.g., ratio of ACK signal or NACK signal) for a previous DL burst (e.g., PDSCH). For example, CWp may be initialized to CWmin, p based on HARQ-ACK feedback for the previous DL burst, CWp may be increased to the next highest allowed value, or CWp may be maintained at the existing value.

(2) Type 2DL CAP method

In a type 2DL CAP, the length of the duration spanned by sensing the time slot sensed as idle prior to transmission(s) is deterministic. The type 2DL CAP is classified into a type 2A DL CAP, a type 2B DL CAP, and a type 2C DL CAP.

The type 2A DL CAP may be applied to the following transmission. In the type 2A DL CAP, the BS may transmit a signal immediately after sensing that the channel is idle during at least the sensing duration tshort_dl=25 μs. Tshort_dl comprises a duration Tf (=16 μs) and an immediately following sensing time slot duration. Tf includes the sensing time slot at the beginning of the duration.

-BS-initiated transmission(s) comprising (i) discovery bursts only, or (ii) discovery bursts multiplexed with non-unicast information, or

-transmission(s) of the BS 25 μs later from the transmission interval(s) of the UE within the shared channel occupancy.

The type 2B DL CAP is suitable for transmission(s) performed by the BS within 16 μs of the transmission gap(s) of the UE within the shared channel occupancy. In the type 2BDL CAP, the BS may transmit a signal immediately after sensing that a channel is idle during tf=16 μs. Tf includes the sensing time slot within the last 9 mus of the duration. The type 2C DL CAP is suitable for transmission(s) performed by the BS within 16 μs of the maximum gap of transmission(s) of the UE within the shared channel occupancy. In the type 2C DL CAP, the BS does not sense a channel before performing transmission.

In a wireless communication system supporting U-band, one cell (or carrier (e.g., CC)) or BWP configured for a UE may be composed of a wideband having a BW greater than that in conventional LTE. However, the BW for CCA based on independent LBT operation may be limited as specified. If a sub-band (SB) in which LBT is separately performed is defined as LBT-SB, a plurality of LBT-SB may be included in one broadband cell/BWP. The RB set constituting the LBT-SB may be configured by higher layer (e.g., RRC) signaling. Accordingly, one or more LBT-SBs may be included in one cell/BWP based on (i) BW of the cell/BWP and (ii) RB set allocation information.

FIG. 10 illustrates the inclusion of multiple LBT-SB's in the U-band.

Referring to fig. 7, a plurality of LBT-SBs may be included in BWP of a cell (or carrier). The LBT-SB may be, for example, the 20-MHz band. The LBT-SB may include a plurality of consecutive (P) RBs in the frequency domain, and thus may be referred to as a (P) RB set. Although not shown, a Guard Band (GB) may be included between LBT-SB. Thus, BWP can be configured in { LBT-SB#0 (RB set#0) +GB#0+LBT-SB#1 (RB set#1+GB#1) +.+ LBT-SB# (k-1) (RB set (#k-1)) }. For convenience, the LBT-SB/RB index may be configured/defined to increase as the frequency band becomes higher starting from the low frequency band.

Energy Detection (ED) threshold determination method

When UE l performs channel access, e.g. Listen Before Talk (LBT) (or Clear Channel Assessment (CCA)) for UL transmissions, the ED threshold (X _Thresh ) Can be provided withIs set to be equal to or smaller than the maximum ED threshold (X _{Thresh_max} ) Is a value of (2).

Here, if a higher layer parameter 'maxEnergyDetectionThreshold' is configured for the UE, X _{Thresh_max} May be set to the value of 'maxeergydetectionthreshold'.

If the higher layer parameter ' maxenergy detection threshold ' is not configured, the UE determines X ' _{Thresh_max} Is a value of (2).

If the higher layer parameter ' energyprotectionthreshold offset ' is configured for the UE, X ' may be adjusted by according to an offset value indicated by ' energyprotectionthreshold offset '. _{Thresh_max} To set X _{Thresh_max} 。

If the higher layer parameter 'energy detection threshold offset' is not configured for the UE, X _{Thresh_max} Can be set as X' _{Thresh_max} 。

Here, when the higher layer parameter 'absenceofAnyOhtertechnology' is configured, it may be determined according to min (T _max +10dB,X _r ) Determination of X' _{Thresh_max} . In this case, if X is defined in regulatory requirements _r The corresponding value may be used. If not, X may be used _r ＝T _max +10dB。

Meanwhile, when the higher layer parameter 'absenseofAnyOhtertechnology' is not configured, X 'may be determined according to the following equation 4' _{Thresh_max} 。

[ equation 4]

Here, T _A ＝10dB、P _H ＝23dBm、P _TX Is a value based on the maximum UE output power, and T _max (dBm)＝10·log10(3.16228·10 ^-8 (mW/MHz). BWMHz (MHz)). Here, BWMHz may represent a channel bandwidth.

In addition, if the higher layer parameter 'absenceofAnyOhtertechnology' is not configured and the higher layer parameter 'ul-toDL-COT-shared-Threshold' is configured for the UE, the base station should determine the transmission power of the base station based on the value of 'ul-toDL-COT-shared-Threshold'.

In addition, if the UE performs a type 1 Channel Access Procedure (CAP) (e.g., cat-3 LBT or Cat-4 LBT) and the UL transmission does not include configuration grant-uplink control information (CG-UCI), or indicates that Channel Occupancy Time (COT) sharing is available when the UL transmission includes CG-UCI, X _{Thresh_max} Is set to the same value as the value of 'ul-toDL-COT-shared-Threshold'.

In the NR system, a large-scale Multiple Input Multiple Output (MIMO) environment in which the number of transmit/receive (Tx/Rx) antennas is significantly increased can be considered. That is, when considering a massive MIMO environment, the number of Tx/Rx antennas may increase to several tens or hundreds. NR systems support communication in the frequency band above 6GHz (i.e., millimeter frequency band). However, the millimeter frequency band is characterized by frequency characteristics in which the signal is attenuated very rapidly according to the distance due to the use of a frequency band that is too high. Thus, in NR systems operating at 6GHz or above, beam Forming (BF) is considered in which signals are transmitted with concentrated energy in a particular direction, rather than omnidirectionally, to compensate for fast propagation attenuation. Therefore, for the purpose of improving performance, flexible resource allocation, and ease of per-frequency beam control in a massive MIMO environment, it is necessary to have a hybrid BF that combines analog BF and digital BF according to the location of the applied BF weight vector/precoding vector.

Fig. 8 is a block diagram illustrating an exemplary transmitter and receiver for mixing BF.

In order to form a narrow beam in a millimeter-wave band, a BF method is mainly considered in which a BS or UE transmits the same signal through a plurality of antennas by applying an appropriate phase difference to the antennas and thus increasing energy only in a specific direction. Such BF methods include digital BF for generating a phase difference for a digital baseband signal, analog BF for generating a phase difference by using a time delay (i.e., cyclic shift) for modulating an analog signal, and hybrid BF with combined digital BF and analog beamforming. Using a Radio Frequency (RF) unit (or transceiver unit (TXRU)) for the antenna element to control transmission power and phase control on an antenna element basis enables an independent BF to be implemented for each frequency resource. However, mounting the TXRU in all about 100 antenna elements is not feasible in terms of cost. That is, a large number of antennas are required to compensate for fast propagation attenuation in millimeter frequencies, and digital BF requires as many RF components (e.g., digital-to-analog converters (DACs), mixers, power amplifiers, and linear amplifiers) as the number of antennas. Thus, implementing digital BF in the millimeter-frequency band increases the price of the communication device. Therefore, when a large number of antennas are required, as in the case of millimeter-frequency bands, analog BF or hybrid BF is considered. In analog BF, multiple antenna elements are mapped to a single TXRU, and the beam direction is controlled by analog phase shifters. Since only one beam direction is generated over the entire frequency band in the analog BF, frequency selective BF may not be implemented with the analog BF. Hybrid BF is an intermediate form of digital BF and analog BF using B RF units of fewer than Q antenna elements. In hybrid BF, the number of beam directions available for simultaneous transmission is limited to B or less, depending on how the B RF units and Q antenna elements are connected.

Beam Management (BM)

BM refers to a series of procedures for acquiring and maintaining a set of BS beams (transmission and reception point (TRP) beams) and/or a set of UE beams available for DL and UL transmission/reception. BM may include the following procedures and terms.

Beam measurement: operation of BS or UE to measure characteristics of received beam-formed signals

-beam determination: operation of BS or UE to select its Tx/Rx beam

-beam scanning: operation of covering a spatial domain by using Tx and/or Rx beams for a prescribed time interval according to a predetermined method

Beam reporting: operation of a UE reporting information about a beam-formed based signal

The BM procedure can be divided into (1) a DL BM procedure using SSB or CSI-RS and (2) a UL BM procedure using SRS. Further, each BM process may include a Tx beam scan to determine Tx beams, and an Rx beam scan to determine Rx beams.

The DL BM procedure may include (1) transmission of beamformed DL RSs (e.g., CSI-RSs or SSBs) from the BS and (2) beam reports from the UE.

The beam report may include the preferred DL RS ID(s) and Reference Signal Received Power (RSRP) corresponding to the preferred DL RS ID(s). The DL RS ID may be an SSB resource indicator (SSBRI) or a CSI-RS resource indicator (CRI).

Dl BM-related beam indication

The UE may receive a list of at least up to M candidate Transmission Configuration Indication (TCI) states for the QCL indication through RRC signaling. M depends on UE capability and may be 64.

Each TCI state may be configured with one RS set. Table 4 describes an example of a TC-State IE. The TC-State IE is related to the QCL type corresponding to one or two DL RSs.

TABLE 7

In table 7, "BWP-Id" identifies DL BWP where the RS is located, "cell" indicates carrier where the RS is located, and "reference antenna port(s) used as QCL source(s) of target antenna port(s) or RS including reference antenna port(s). The target antenna port(s) may be used for CSI-RS, PDCCH DMRS or PDSCH DMRS.

3. Quasi co-location (QCL)

The UE may receive a list of up to M TCI state configurations to decode PDSCH based on detected PDCCHs carrying DCI intended for a given cell. M depends on UE capability.

As described in table 7, each TCI-State includes parameters for establishing a QCL relationship between one or more DL RSs and PDSCH DM-RS ports. The QCL relationship is established using RRC parameter QCL-Type1 for the first DL RS and RRC parameter QCL-Type2 (if configured) for the second DL RS.

The QCL Type of each DL RS is given by a parameter "QCL-Type" included in the QCL-Info, and may have one of the following values.

- 'QCL-TypeA': { Doppler shift, doppler spread, average delay, delay spread }

- 'QCL-TypeB': { Doppler shift, doppler spread }

- 'QCL-TypeC': { Doppler shift, average delay }

- 'QCL-TypeD': { spatial Rx parameters })

For example, if the target antenna port is for a particular NZP CSI-RS, the NZP CSI-RS antenna port may be indicated/configured to be from the QCL-Type a angle with a particular TRS QCL and from the QCL-Type D angle with a particular SSB QCL. Upon receiving the indication/configuration, the UE may receive the NZP CSI-RS using a Doppler value (Doppler value) and a delay value measured in the QCL-type a TRS and apply an Rx beam for receiving the QCL-type SSB to receive the NZP CSI-RS.

UL BM procedure

In the UL BM, beam reciprocity (or beam correspondence) between Tx and Rx beams may or may not be established depending on the implementation of the UE. If Tx-Rx beam reciprocity (beam reciprocity) is established at both the BS and the UE, the UL beam pair may be obtained from the DL beam pair. However, if Tx-Rx beam reciprocity is not established at either BS or UE, a procedure for determining UL beam is required separately from the determination of DL beam pair.

In addition, even when both the BS and the UE maintain beam correspondence, the BS may apply UL BM procedures to determine DL Tx beams without requesting the UE to report its preferred beam.

UL BM may be performed based on beamformed UL SRS transmissions. Whether to perform UL BM on SRS resource set may be determined by a use parameter (RRC parameter). If the purpose is determined to be a BM, only one SRS resource may be transmitted for each of the plurality of SRS resource sets at a given time.

The UE may be configured (via RRC signaling) with one or more SRS resource sets, where the one or more SRS resource sets are configured by SRS-resource set (RRC parameters). For each SRS resource set, the UE may be configured with k≡1 SRS resources, where K is a natural number and the maximum value of K is indicated by srs_capability.

Similar to DL BM, UL BM procedure can also be divided into Tx beam scanning at UE and Rx beam scanning at BS.

In the proposed method described later, a beam may refer to an area for performing a specific operation (e.g., LBT or transmission) by focusing power in a specific direction and/or a specific space. In other words, the UE or the BS may perform operations such as LBT or transmission by targeting a specific region (i.e., beam) corresponding to a specific space and/or a specific direction. Thus, each beam may correspond to each space and/or each direction. In addition, the UE or BS may use a spatial domain filter corresponding to each space and/or each direction in order to use each beam. That is, one spatial domain filter may correspond to one or more beams. The UE or BS may perform operations such as LBT or transmission using spatial domain filters corresponding to beams (or space and/or direction) to be used.

For example, the UE or the BS may perform LBT using a spatial domain filter corresponding to an LBT beam in space and/or direction for a corresponding LBT beam, or perform DL/UL transmission using a spatial domain filter corresponding to a Tx beam in space and/or direction for a corresponding Tx beam.

In a high frequency band of 52.6GHz or higher, an omni-directional LBT (hereinafter referred to as O-LBT) that omni-directionally performs LBT by a technique such as analog beamforming using a plurality of antennas and a directional LBT (hereinafter referred to as D-LBT) that performs Listen Before Talk (LBT) only in a specific beam direction having omni-directional transmission and reception may be considered since path loss is relatively greater than that in a low frequency band.

In this case, since the O-LBT and the D-LBT are different in the region and direction in which the LBT is performed, it is necessary to set different Energy Detection (ED) thresholds to determine IDLE/BUSY of the channel by energy. In addition, since LBT has directivity, if beams of different directions are multiplexed within the COT successfully obtained by D-LBT or DL/UL beams are used for DL/UL transmission and reception by DL/UL switching, the direction in which LBT is performed and the ED threshold are closely related, and an appropriate ED threshold setting and multiplexing method are required.

A typical CAP performed for transmissions in the U-band is LBT. LBT is a mechanism that prevents collisions between transmissions by allowing transmission of corresponding signals when the noise level as a result of comparing the surrounding interference level measured by the BS and/or UE to which the signals are to be transmitted with a specific threshold (such as an ED threshold) is less than a specific level.

FIG. 9 illustrates an exemplary D-LBT and an exemplary O-LBT.

Fig. 9 (a) illustrates a D-LBT including a specific beam direction LBT and/or beam group unit LBT, and fig. 9 (b) illustrates an O-LBT.

In a conventional NR-U system (e.g., rel-16 NR-U), if the channel is determined to be idle by performing CAP (i.e., LBT), a DL/UL signal/channel has been transmitted as described with reference to fig. 9. On the other hand, in the conventional NR-U system, LBT bands have been aligned with LBT bands of other RATs to coexist with other RATs (e.g., wi-Fi), and CAP (i.e., LBT) has been omnidirectionally performed. In other words, a non-directional LBT has been performed in conventional NR-U systems.

However, rel-17 NR-U for transmitting DL/UL signals/channels in a higher band (e.g., a 52.6GHz band or higher) than the 7GHz U band used in conventional NR-U systems may utilize directional LBT (D-LBT) that transmits signals/channels by focusing energy in a specific beam direction in order to overcome a greater path loss than in the 7GHz band used in conventional systems. That is, in Rel-17 NR-U, path loss can be reduced by D-LBT, DL/UL signals/channels can be transmitted over a wider coverage, and efficiency can be improved even if coexisting with other RATs (e.g., wiGig).

Referring to fig. 9 (a), when a beam group is composed of beams #1 to #5, performing LBT based on beams #1 to #5 may be referred to as a beam group unit LBT. In addition, performing LBT by any one of beams #1 to #5 (e.g., beam # 3) may be referred to as a specific beam direction LBT. In this case, beams #1 to #5 may be continuous (or adjacent) beams, but may also be discontinuous (or non-adjacent) beams. Further, the number of beams included in the beam group is not necessarily plural, and a single beam may form one beam group.

FIG. 7 (b) illustrates O-LBT. When the omni-directional beams constitute one beam group and LBT is performed in units of the corresponding beam group, this may be interpreted as performing omni-directional LBT (O-LBT). In other words, if beams of all directions (i.e., omni-directional beams as a beam set covering a specific sector in a cell) are included in one beam group, this may mean O-LBT.

In other words, in the case of high frequency bands, the coverage may be limited due to significant path loss. To overcome this coverage problem, multi-antenna techniques may be used. For example, a narrow beam transmission that transmits a signal by concentrating energy in a specific direction may be performed instead of an omni-directional transmission.

In the high frequency U-band, along with CAPs such as the LBT described above, beam-based transmissions in combination therewith need to be considered. For example, in order to perform D-LBT in a specific direction, D-LBT may be performed only in a corresponding direction, or LBT may be performed in beam groups including beams of the corresponding direction. Then, if it is determined that the channel is idle, transmission may be performed. Here, the beam group may include a single beam or a plurality of beams. If the beam set comprises omni-directional beams, the D-LBT may be extended to O-LBT.

Since the beam-based transmission described above concentrates energy in a particular direction to transmit signals, interference effects on nearby base stations/UEs (excluding nodes located in the transmission direction) may be relatively small compared to omni-directional transmissions. In other words, spectrum sharing can be considered to be performed naturally, since beam-based transmissions only interfere in a particular direction. Accordingly, if certain conditions are satisfied, beam-based transmission may be performed without performing LBT to increase channel access opportunities and improve system performance.

Information about a beam group including a beam and at least one beam included in each beam group may be configured, and a Contention Window Size (CWS) and a backoff counter value may be managed for a single beam or each beam group. Thus, when performing LBT, events such as CWS reset/increase, backoff counter decrease, etc. may have an effect between each beam and the beam group including each beam. For example, since feedback on data transmitted through a specific beam direction LBT is NACK, if the CWS value of the corresponding beam direction increases, the corresponding CWS increase is also reflected in CWS managed in a beam group including the corresponding beam, so that the CWS value of the beam group can be increased. On the other hand, even if the CWS value of the corresponding beam direction increases, the CWS value of the beam group can be independently managed without affecting the beam group including the corresponding beam. In addition, as described above, the back-off counter value per beam and the back-off counter value per beam group may be managed independently and may affect each other by interdependence.

In addition, under certain conditions, the per-beam LBT and the beam group LBT may be performed by switching between each other. In the case of UL transmission, the base station may indicate an LBT type (i.e., per beam LBT and beam group LBT) to be used between two LBT types. In the case of configuring a grant (CG) UL transmission, when resources for transmitting CG UL are configured, LBT types to be performed in each resource may be configured together. In addition, if delay sensitive data transmission is indicated with LBT in a specific beam direction, data may not be transmitted due to LBT failure. Accordingly, the channel access occasion may be increased by allocating a plurality of LBT occasions to other beams within the beam group including the corresponding beam.

In the present disclosure, the per-beam LBT procedure or the beam group unit LBT procedure may basically represent a category-3 (category-3) or a category-4 LBT based on random back-off. In addition, per beam LBT performs carrier sensing in a specific beam direction and is compared with the ED threshold. If the energy measured by carrier sensing is below the ED threshold, the LBT may treat the channel corresponding to the beam direction as IDLE. If the energy measured by carrier sensing is higher than the ED threshold, the LBT may determine that the channel corresponding to the beam direction is BUSY.

The beam group LBT procedure is to perform the above LBT procedure in all beam directions included in the beam group. If there are beams (e.g., representative beams) in a particular direction that is preconfigured/indicated within the beam group, a random back-off based LBT procedure can be representatively performed using the corresponding beams in a manner similar to the multi-CC LBT, and a class-1 (Cat-1) or a class-2 (Cat-2) LBT is performed for the remaining beams included in the beam group instead of the random back-off based LBT. Thus, this may mean that a signal is sent when LBT is successful. Meanwhile, in the beam group LBT process, according to the specification of each country/region, a random back-off based LBT process is performed through a representative beam, and signals may be transmitted through the remaining beams included in the beam group, respectively, without performing LBT (no LBT).

Before describing the proposed method, the NR based channel access scheme for unlicensed bands used in the present disclosure is classified as follows.

Category 1 (CAT-1): the next transmission immediately follows the previous transmission after a switching gap within the COT, and the switching gap is shorter than 16us, even including transceiver turn-around time. Cat-1 LBT may correspond to the type 2C CAP described above.

-category 2 (Cat-2): there is no back-off LBT method. The transmission may be performed immediately upon confirmation that the channel is idle during a specific period of time shortly before the transmission. Cat-2LBT may be subdivided according to the length of the minimum sensing duration required for channel sensing immediately before transmission. For example, a Cat-2LBT with a minimum sensing duration of 25us may correspond to the type 2A CAP described above, and a Cat-2LBT with a minimum sensing duration of 16us may correspond to the type 2B CAP described above. The minimum sensing duration is merely exemplary, and a minimum sensing duration of less than 25us or 16us (e.g., a minimum sensing duration of 9 us) is also available.

-category 3 (Cat-3): LBT method with backoff based on fixed Contention Window Size (CWS) i. The transmitting entity selects the random number N in the range of 0 to the (fixed) maximum CWS value and decrements the counter value each time the channel is determined to be idle. When the counter value reaches 0, the transmitting entity is allowed to perform the transmission.

Category 4 (Cat-4): LBT method with variable CWS based backoff. The transmitting entity selects the random number N in the range of 0 to the (variable) maximum CWS value and decrements the counter value each time the channel is determined to be idle. When the counter value reaches 0, the transmitting entity is allowed to perform the transmission. If the sending entity receives feedback indicating a failure to receive a transmission, the sending entity will increment the maximum CWS value by one level, reselect a random number within the incremented CWS value, and perform an LBT procedure. Cat-4 LBT may correspond to type 1CAP described above.

The definition of QCL described in this disclosure may follow one of the above definitions of QCL. In addition, similarly, the QCL concept definition may be modified to a form that may be assumed to be transmitted from a common location (co-location) between antenna ports for which QCL assumptions are established (e.g., a form in which a UE may assume antenna ports transmitted at the same transmission point), and the ideas of the present disclosure include similar modified examples. In this disclosure, the above QCL related definitions are used interchangeably for ease of description.

According to the definition above, for "non-quasi co-located (NQC) antenna ports", the UE cannot assume the same large-scale channel characteristics between the antenna ports. That is, in this case, a typical UE receiver should perform independent processing for each configured non-quasi co-located (NQC) antenna port for timing acquisition and tracking, frequency offset estimation and compensation, delay estimation, doppler estimation, and the like. The advantage is that the following operation of the UE can be performed between antenna ports where QCL can be assumed.

For delay spread and doppler spread, the UE may apply the power delay profile, delay spread and doppler spectrum of one antenna port and the doppler spread estimation result equally to Wiener (Wiener) filters for channel estimation of other antenna ports.

For frequency shift and receive timing, the UE may perform time and frequency synchronization for one antenna and then apply the same synchronization to demodulation of the other antenna port.

For average received power, the UE may use an average of RSRP measurements of multiple antenna ports.

On the other hand, if beam reciprocity is established between DL and UL beams, a procedure for determining a DL beam pair or a procedure for determining a UL beam pair may be omitted. The same applies to the case where the beam correspondence is also established.

Here, establishment of beam reciprocity (or beam correspondence) may mean that it is assumed that a BS Tx beam and a BS Rx beam are matched in communication between a BS and a UE, and that a UE Tx beam and a UE Rx beam are matched in communication between a BS and a UE. Here, the BS Tx beam and the BS Rx beam may represent a DL Tx beam and a DL Rx beam, respectively, and the UE Tx beam and the UE Rx beam may represent an UL Tx beam and an UL Rx beam, respectively. Here, the Tx beam may represent a transmit beam and the Rx beam may represent a receive beam.

All DL signals/channels (or UL signals/channels) included in one TX burst are preferably configured as signals/channels having a spatial (partial) QCL relationship for the following reasons. For example, as shown in fig. 10, when a TX burst consisting of a total of four slots is transmitted after LBT is successful, the BS may transmit the TX burst in the fourth slot in the beam C direction after transmitting the TX burst during three slots in the beam a direction.

However, when the BS transmits a signal in the beam a direction, the Wi-Fi AP coexisting in the corresponding U band does not detect the signal transmitted in the beam a direction. Thus, after determining that the channel is IDLE, the Wi-Fi AP may successfully perform LBT and then begin transmitting and receiving signals. In doing so, when the BS transmits a signal from slot #k+3 in the beam C direction, it may act as interference to the signal of the corresponding Wi-Fi. Similarly to this case, since the BS for transmitting with beam a transmits by changing the beam direction without additional LBT, it may cause interference to another coexisting wireless node, and thus it is preferable not to change the direction of the Tx beam of the Tx burst transmitted after the BS has successfully performed LBT.

In the NR system, a method of signaling beam information for UL transmission and reception to a UE by associating DL signals and UL signals is considered. For example, if there is a beam direction generated by the UE in a channel state information-reference signal (CSI-RS) resource by connecting the CSI-RS resource with a Sounding Reference Signal (SRS) resource, the UE may transmit an UL signal using a Tx beam corresponding to a CSI-RS Rx beam when the SRS is transmitted in the SRS resource connected to the corresponding CSI-RS resource (or when the PUSCH is scheduled by an UL grant, the SRS resource connected to the corresponding CSI-RS resource is signaled on the UL grant). In doing so, if the UE has beam-correspondence capability, the relationship between a specific Rx beam and a specific Tx beam may be configured at the time of UE implementation. Alternatively, if the UE does not have beam-correspondence capability, the relationship between a specific Rx beam and a specific Tx beam may be configured through training between the BS and the UE.

Thus, when defining the association between DL signals and UL signals, COT may be allowed to be shared between DL TX bursts consisting of DL signals/channels in spatial (partial) QCL relation to the corresponding DL signals and UL TX bursts consisting of UL signals/channels in spatial (partial) QCL relation to the UL signals associated with the corresponding DL signals.

Here, the UL signal/channel may indicate at least one of the following signals/channels.

SRS (sounding RS), DMRS for PUCCH, DMRS, PUCCH, PUSCH for PUSCH and PRACH

Here, the DL signal/channel may indicate at least one of the following signals/channels.

PSS (primary synchronization signal), SSS (secondary SS), DMRS, PBCH, TRS (tracking reference signal) for PBCH or CSI-RS for tracking, CSI-RS for CSI (channel state information) acquisition and CSI-RS for RRM measurement, CSI-RS for beam management, DMRS for PDCCH, DMRS for PDSCH, PDCCH (or PDCCH may transmit core (control resource set)), PDSCH, and signals introduced for tracking or (fine) time/frequency synchronization or coexistence or power saving or frequency reuse factor=1, etc., by being arranged before the TX burst as the above listed signals, modifications of the corresponding signals, or newly introduced signals.

On the other hand, each of the suggested methods described below may be applied by combining with other suggested methods unless they are contrary to each other.

Before describing the proposed method of the present disclosure, the overall operation procedure of the UE, BS and network implementing the proposed method of the present disclosure will be studied.

Fig. 11 to 13 are diagrams for describing overall operation procedures of a UE, a BS, and a network to transmit and receive uplink signals according to the suggested method of the present disclosure.

Fig. 14 to 16 are diagrams for describing overall operation procedures of a UE, a BS, and a network to transmit and receive downlink signals according to the suggested method of the present disclosure.

Fig. 11 is a diagram for describing an operation procedure of a UE for transmitting an uplink signal according to the suggested method of the present disclosure.

Referring to fig. 11, the ue may determine an Energy Detection (ED) threshold based on at least one first UL signal (S1101). For example, the UE may determine at least one first UL signal based on [ suggested method #2] and/or [ suggested method #3] and an ED threshold based on the at least one first UL signal, which is consulted to determine the ED threshold.

The UE may perform Listen Before Talk (LBT) based on the ED threshold (S1103). In this case, the LBT may be performed based on the D-LBT. For example, the corresponding LBT may be performed based on the [ suggested method #1 ]. However, it is not limited by the [ suggested method #1 ]. If a plurality of Tx beams are multiplexed and UL signals can be transmitted through the corresponding Tx beams, any method may be used to perform LBT.

The UE may transmit at least one first UL signal and/or a second UL signal within a Channel Occupation Time (COT) acquired through the LBT. For example, at least one first UL signal and/or second UL signal may be determined and transmitted based on [ suggested method #2] and/or [ suggested method # 3].

Fig. 12 is a diagram for describing an operation procedure of a BS receiving an UL signal according to the proposed method of the present disclosure.

The BS may transmit first information for scheduling at least one first UL signal S1201.

The BS may transmit second information for scheduling a second UL signal S1203.

For example, the transmission timing point of the first information for scheduling the at least one first UL signal and/or the second information for scheduling the second UL signal may be determined based on the [ suggested method #2] and/or the [ suggested method # 3].

The BS may receive at least one first UL signal and/or a second UL signal S1205. For example, the BS may receive at least one first UL signal and/or second UL signal based on the [ suggested method #2] and/or the [ suggested method # 3].

Fig. 13 is a diagram illustrating an operation procedure of a network for transmitting and receiving uplink signals according to the suggested method of the present disclosure.

The BS may transmit first information for scheduling at least one first UL signal to the UE (S1301).

The UE may determine an Energy Detection (ED) threshold based on the at least one first UL signal (S1305). For example, the UE may determine at least one first UL signal based on [ suggested method #2] and/or [ suggested method #3] and an ED threshold based on the at least one first UL signal, which is referenced to determine the ED threshold.

The UE may perform Listen Before Talk (LBT) based on the ED threshold (S1307). In doing so, LBT may be performed based on D-LBT. For example, the corresponding LBT may be performed based on the [ suggested method #1 ]. However, it is not limited by the [ suggested method #1], and any method capable of multiplexing a plurality of Tx beams and transmitting UL signals through the corresponding Tx beams may be used to perform LBT.

The UE may transmit at least one first UL signal and/or a second UL signal to the BS within a Channel Occupation Time (COT) acquired through the LBT. For example, at least one first UL signal and/or second UL signal may be determined and transmitted based on [ suggested method #2] and/or [ suggested method #3].

Meanwhile, the BS may transmit second information for scheduling a second UL signal to the UE. For example, the BS may transmit the second information between a timing point at which the first information is transmitted to the UE and a timing point at which the ED threshold is determined by the UE (S1303-1). Alternatively, the BS may transmit the second information to the UE before performing LBT by determining the ED threshold or at a timing point of performing LBT (S1303-3). Alternatively, the BS may transmit the second information to the UE within the COT acquired through the LBT (S1303-5). For example, the transmission and transmission timing of the second information for scheduling the second UL signal may be based on [ suggested method #2] and/or [ suggested method #3].

Fig. 14 is a diagram illustrating an operation procedure in which a UE receives a DL signal according to the suggested method of the present disclosure.

The UE may receive information for scheduling DL signals (S1401). In addition, the UE may receive a DL signal based on the correspondence information (S1403). In doing so, the DL signal may be received based on [ suggested method #1 ].

Fig. 15 is a diagram illustrating an operation procedure of a BS for transmitting a DL signal according to the proposed method of the present disclosure.

The BS may perform LBT (S1501) and transmit information for scheduling DL signals (S1503). For example, the base station may perform LBT based on the proposed method # 1.

The BS performs LBT for DL signal transmission (S1505). For example, the BS may perform LBT based on the [ suggested method #1 ]. However, if the DL signal is transmitted within the COT acquired through the LBT performed in the previous step, the corresponding step may be omitted, or a non-random back-off based LBT (e.g., cat-1 LBT or Cat-2 LBT) may be performed. The BS may transmit a DL signal based on the correspondence information (S1507).

Fig. 16 is a diagram illustrating an operation procedure of a network for transmitting DL signals according to the suggested method of the present disclosure.

The BS may perform LBT (S1601) and transmit information for scheduling DL signals to the UE (S1603). For example, the BS may perform LBT based on the [ suggested method #1 ].

The BS may perform LBT for DL signal transmission (S1605). For example, the BS may perform LBT based on the [ suggested method #1 ]. However, if the DL signal is transmitted within the COT acquired through the LBT performed in the previous step, the corresponding step may be omitted, or a non-random back-off based LBT (e.g., cat-1 LBT or Cat-2 LBT) may be performed. The BS may transmit a DL signal to the UE based on the correspondence information (S1607).

[ suggested method #1]

When the BS or the UE transmits a plurality of Tx beams through Time Division Multiplexing (TDM) within a Channel Occupation Time (COT), a method of performing per-beam LBT (e.g., performing random back-off based Cat-3 LBT or Cat-4 LBT for each sensing beam) through each of a plurality of sensing beams respectively covering a direction and an interference range of the multiplexed Tx beams will be described. In this case, each of the time division multiplexed Tx beams may have a different direction, and some or all of the Tx beams may have the same direction. In addition, each sensing beam may have a different direction, and some or all of the sensing beams may have the same direction.

Meanwhile, in embodiments #1-1 to #1-4, the time T as a reference for performing Cat-2 LBT again may be preset or set through RRC. Here, T may represent a reference time considered to guarantee the validity of the per-beam LBT of all Tx beams. For example, the total time required per beam LBT for all Tx beams is less than T (or less than T), which may indicate that LBTs generated from the first Tx beam to the last Tx beam may be considered valid.

On the other hand, the total time required for per-beam LBT of all Tx beams is equal to or greater than (or greater than) T, which may indicate that the validity of at least one LBT generated from the first Tx beam to the last Tx beam cannot be guaranteed. Thus, this may indicate that the presence or absence of IDLE of the channel should be checked again by at least a short interval of LBT (e.g. Cat-2 LBT).

1. Example #1-1

If the total time required to perform LBT per beam by a plurality of sensing beams is equal to or less than T (or less than T), transmission may be started with the first Tx beam immediately after LBT per beam has succeeded.

2. Example #2

If the total time required to perform LBT per beam by a plurality of sensing beams is equal to or greater than T (or greater than T), cat-2 LBT may be performed again by a single wide beam or omni-directional beam including all Tx beams immediately after LBT per beam has been successful. If Cat-2 LBT is successful, transmission may begin using the first Tx beam. For example, a single wide beam containing all Tx beams may be a beam covering both the direction and interference range of multiple Tx beams. In other words, a single wide beam may include beams applied to all Tx beams. For example, a single wide beam is applied to all Tx beams to sense the direction and interference range of all Tx beams.

3. Examples #1 to 3

When the total time required to perform LBT per beam is equal to or greater than T (or greater than T) through a plurality of sensing beams, if Cat-2 LBT through a sensing beam corresponding to a first Tx beam is successful immediately after LBT per beam has been successful, transmission through the first Tx beam may be started. In addition, each time a Tx beam is switched, if Cat-2 LBT succeeds in using a sensing beam corresponding to the Tx beam before transmitting the corresponding Tx beam, the corresponding Tx beam may be transmitted.

4. Examples #1 to 4

When the LBT completion timing point of the sensing beam of each beam LBT is T1, which is the last to be performed among the sensing beams of each beam LBT, at least one of the above-described embodiments #1-1 to #1-3 may be applied based on a comparison with the maximum value T among the time differences between the completion timing points of each sensing beam LBT previously performed.

Here, the T value may be preconfigured/indicated from the BS. In addition, each sensing beam may be identical (in shape and size) to a specific Tx beam or a beam including a Tx beam (its shape and size), and may include a wide beam as compared to the Tx beam. Here, the fact that the same shape and size as or including the Tx beam may represent the same beam direction and interference range as or including the Tx beam. For example, the sensing beam is applied to a specific beam, and it is expected that a space corresponding to the direction and the interference range (i.e., the shape and size of the Tx beam) of each Tx beam is sensed, and the sensing range may be at least the same as or greater than the direction and the interference range (or the shape and size of the Tx beam) of the corresponding Tx beam. Further, in the above case, in order to sense the plurality of Tx beams, the corresponding sensing may be performed using a plurality of sensing beams, the number of which is equal to or greater than the number of the plurality of Tx beams. For example, the plurality of sensing beams and the plurality of Tx beams may correspond one-to-one or many-to-one as if the plurality of sensing beams sensed one Tx beam.

In addition, a sensing beam corresponding to each Tx beam may be configured/indicated in advance for the UE.

Hereinafter, embodiments #1-1 to #1-4 will be described in detail.

When transmission is performed only in a specific beam direction, directional LBT (D-LBT) may be performed through a specific sensing beam instead of omni-directional LBT, and COTs in the corresponding beam direction may be acquired.

However, if a plurality of Tx beams are transmitted by time division multiplexing within the acquired COT, LBT coverage may be necessary for COT acquisition to the interference range of all Tx beams to be transmitted by time division multiplexing. In doing so, the LBT may be performed by a single wide beam covering the directions and interference ranges of all Tx beams to be multiplexed within the COT, or the COT may be acquired by sequentially performing per-beam LBT by respective sensing beams respectively covering the Tx beam interference ranges. In this case, the sensing beam covering the interference range of the corresponding Tx beam may also be time division multiplexed.

In this case, each beam LBT through the plurality of sensing beams may be performed according to the order of Tx beams to be transmitted in the COT. For example, the Cat-3 LBT or Cat-4 LBT based on the random backoff may be performed using a sensing beam corresponding to a Tx beam to be transmitted first, and then the Cat-3 or Cat-4 LBT may be performed using a sensing beam corresponding to a next Tx beam. In this case, the COT may be acquired after the per-beam LBT has been completed. In this case, the COT may be acquired only when the per-beam LBT of all Tx beams succeeds, or the COT for the Tx beam for which only the LBT has succeeded may be acquired based on the per-beam LBT.

If the COT is acquired for only Tx beams for which LBT has been successfully performed, in the embodiments described below, the first Tx beam for which LBT has been successfully performed among the Tx beams may be the first Tx beam for which transmission is performed immediately after LBT success, or an additional Cat-2 LBT, according to the total time T, and the order of the transmitted Tx beams may be determined based only on the Tx beams for which LBT has been successfully performed.

For example, LBT is performed for each of a total of eight Tx beams (e.g., tx beam #0 to Tx beam # 7), and if LBT for only Tx beams #2, #3, #5, and #7 succeeds, the first Tx beam in the embodiment described later may be Tx beam #2. If the LBT for all Tx beams is successful, the first Tx beam may be Tx beam #0.

On the other hand, when the first Tx beam is actually transmitted, if a considerable time has elapsed since a timing point at which LBT is performed with the corresponding sensing beam, the LBT performance result may not be valid any more at the time of transmitting the Tx beam.

Thus, depending on the total time T required to perform the per-beam LBT, the transmission of the first Tx beam may be performed immediately after the LBT is successful, or additional Cat-2 LBT may be performed before the transmission through each Tx beam.

If the total time required to perform LBT per beam by a plurality of sensing beams is equal to or less than T (or less than T), transmission may be sequentially started with the first Tx beam immediately after LBT per beam has succeeded according to embodiment # 1-1. However, if the total time required to perform the per-beam LBT through the plurality of sensing beams is equal to or greater than T (or greater than T), the Cat-2 LBT may be performed again through a single wide beam or omni-directional beam including all Tx beams immediately after the per-beam LBT has been successful, and transmission may be started only when the Cat-2 LBT is successful.

Alternatively, if the total time required to perform the LBT per beam through the plurality of sensing beams is equal to or greater than T (or greater than T), according to embodiments #1-3, cat-2 LBT may be performed through the sensing beam corresponding to the first Tx beam immediately after the LBT per beam has succeeded. If Cat-2 LBT is successful, transmission of the first Tx beam may be started. Each time a Tx beam is switched, cat-2 LBT is performed by a sensing beam corresponding to the corresponding Tx beam before each Tx beam is transmitted. Only when each Cat-2 LBT succeeds, transmission can be performed in the direction of the corresponding Tx beam.

Here, the T value determining whether additional LBT execution is required compared to the total time required to execute per beam LBT may be preconfigured/indicated by the BS. In addition, each sensing beam may be the same (in shape and size) as or include a Tx beam (in shape and size) corresponding to the corresponding sensing beam, and may include a beam wider than the corresponding Tx beam.

Meanwhile, sensing beams respectively corresponding to Tx beams may be previously configured/indicated to the UE.

The above-described embodiments #1-1 to #1-3 are used to determine whether to start transmission of the Tx beam by performing additional procedures such as Cat-2 LBT based on a comparison of the total time required for per-beam LBT with the previously configured/indicated T value after LBT is completed. On the other hand, embodiment #1-4 may apply at least one of embodiments #1-1 to #1-3 by comparing the maximum value among differences between timing points at which LBT is completed through each sensing beam with the previously configured/indicated value.

For example, there is a sensing beam 1/2/3 corresponding to Tx beam a/B/C, the timing point at which all per-beam LBTs are completed is named T1, the last LBT completion timing point of sensing beam 1 is T1 (i.e., assuming that the last sequential sensing beam of per-beam LBT is sensing beam 1), the LBT completion timing point of sensing beam 2 is T2, and the LBT completion timing point of sensing beam 3 is T3. In this case, the maximum value selected from (T1-T2) and (T2-T3) is compared with the T value previously configured/indicated by the BS. The channel access procedure and transmission per beam can be performed by performing the embodiment #1-1 in the case where the maximum value is equal to or less than the T value (or less than the T value), or by applying the embodiment #1-2 or the embodiment #1-3 in the case where the maximum value is greater than or equal to the T value (or greater than the T value).

According to the embodiment of the above-mentioned [ suggested method #1], when a plurality of Tx beams are time-division multiplexed, since the beam direction in which LBT is first performed may be long since all per-beam LBTs are performed (for example, because the validity time of the expected validity of the LBT result may be exceeded), LBT needs to be performed only once, thereby increasing the validity of D-LBT and minimizing collision with transmission of another UE/BS.

[ suggested method #2]

When the BS schedules consecutive UL transmissions to a single UE or multiple UEs, multiple UL Tx beams are multiplexed and transmitted within the same COT. In doing so, when the COT is acquired by configuring an ED threshold (hereinafter referred to as "t_ref") with reference to the maximum Effective Isotropic Radiated Power (EIRP) (hereinafter referred to as "p_max") in Tx beams to be transmitted within the COT or the average EIRP (hereinafter referred to as "p_avg") of Tx beams to be transmitted in the COT, an ED threshold configuration method and an LBT procedure according to the transmission power of one or more other UL transmissions to be transmitted within the remaining COT will be described.

For example, the one or more other UL transmissions to be sent within the remaining COTs are UL transmissions other than those considered in calculating the ED threshold for the COT acquisition of the UE, but may represent UL transmission scheduling within the same COT as the UL transmissions considered in calculating the ED threshold. In other words, one or more other UL transmissions to be sent within the remaining COTs may represent UL transmissions other than those involved in the UE determining p_max or p_avg to calculate the ED threshold in UL transmissions scheduled within the same COT.

1. Example #2-1

The maximum transmission power of UL transmissions to be sent within the remaining COTs may be set/limited to p_max or p_avg so as not to exceed p_max or p_avg for ED threshold calculation for the first COT acquisition. For example, when one or more UL transmissions other than the UL transmission involved in the UE determining p_max or p_avg for ED threshold calculation to acquire the COT (i.e., UL transmission not involved in determining p_max or p_avg for ED threshold calculation) are scheduled within the same COT, the highest transmission power of the corresponding one or more UL transmissions may be limited to p_max or p_avg, although the maximum transmission power of the corresponding one or more UL transmissions is configured to exceed p_max or p_avg.

2. Example #2-2

Cat-2 LBT is performed based on ED threshold T_new calculated from P_new (> P_max or P_avg) to use more power (hereinafter "P_new") for another UL transmission to be sent in the remaining COT than P_max or P_avg used to calculate ED threshold T_ref for the first COT acquisition. If Cat-2 LBT is successful, another UL transmission may be performed. In this case, t_new may be a value lower than t_ref.

3. Examples #2 to 3

A new COT is initiated by performing Cat-3 or Cat-4 LBT, which is performed in accordance with an ED threshold t_new calculated based on p_new (> p_max or p_avg), to use more power (hereinafter referred to as "p_new") than p_max or p_avg used to calculate an ED threshold t_ref for the first COT acquisition for another UL transmission to be transmitted in the remaining COT, and the other UL transmission may be performed within the new COT. In this case, t_new may be a value lower than t_ref.

4. Examples #2 to 4

When a power greater than p_max or p_avg (hereinafter referred to as "p_new") used to calculate ED threshold t_ref for the first COT acquisition is used for another UL transmission to be transmitted within the remaining COT, the corresponding other UL transmission may be discarded.

Hereinafter, embodiments #2-1 to #2-4 of [ suggested method #2] will be described in detail.

For example, suppose that the BS continuously schedules UL #1 transmission, UL #2 transmission, and UL #3 transmission within the same COT. When LBT is performed to acquire COT before ul#1 and ul#2 transmission, the UE knows the presence or absence of scheduling for ul#1 and ul#2 and configures transmission power of ul#1 and ul#2. However, the UE may not know whether there is scheduling for UL #3 or it may be a timing point before configuring the transmission power of UL #3 (although it is scheduled).

For example, three examples, which are some examples of the above-described cases, will be described with reference to fig. 17. As a first example, referring to fig. 17 (a), since dci#1 and dci#2 (or the same DCI or RRC configured) are received or decoded before the UE calculates the ED threshold, ul#1 and ul#2 corresponding to dci#1 and dci#2 (or the same DCI or RRC configured) are scheduled in the COT to be acquired after the LBT and transmission powers of ul#1 and ul#2 are acquired. However, UL #3 is scheduled by DCI #3 received or decoded after COT initiation, and the transmission power of UL #3 is not reflected in ED threshold calculation and LBT execution.

As a second example, referring to fig. 17 (b), since dci#1 and dci#2 (or the same DCI or RRC configured) are received or decoded before the UE calculates the ED threshold, ul#1 and ul#2 corresponding to dci#1 and dci#2 (or the same DCI or RRC configured) are scheduled in the COT to be acquired after the LBT and transmission powers of ul#1 and ul#2 are acquired. However, ul#3 is scheduled by dci#3 received or decoded after LBT execution, or transmission power of ul#3 is acquired after LBT execution, and thus transmission power of ul#3 is not reflected in ED threshold calculation and LBT execution.

As a third example, referring to fig. 17 (c), since dci#1 and dci#2 (or the same DCI or RRC configured) are received or decoded before the UE calculates the ED threshold, ul#1 and ul#2 corresponding to dci#1 and dci#2 (or the same DCI or RRC configured) are scheduled in the COT to be acquired after the LBT and transmission powers of ul#1 and ul#2 are acquired. However, UL #3 is scheduled by DCI #3 received or decoded after the UE has started to calculate the ED threshold, or the transmission power of UL #3 is acquired after the start of calculating the ED threshold, and thus the transmission power of UL #3 is not reflected in ED threshold calculation and LBT execution.

In the above case, since the COT is acquired by performing LBT in such a manner that an ED threshold (i.e., T ref) is configured by referring to the maximum EIRP (i.e., p_max) or the average EIRP (e.g., p_avg) of Tx beams to be transmitted in the COT among Tx beams to be transmitted in the COT (i.e., IDLE/BUSY by evaluating channels), it may be necessary to configure/limit other UL transmitted in the remaining COT so as not to exceed p_max or p_avg calculated for ED threshold for the first COT acquisition.

Thus, as described in embodiment #2-1, COT may be initiated by performing LBT as follows: the application refers to an ED threshold calculated from the maximum EIRP p_max among UL transmissions (e.g., UL #1 and UL # 2) captured by the UE or the average EIRP p_avg of EIRP of UL captured UL transmissions (e.g., UL #1 and UL # 2) before the timing point at which the LBT is first performed by the UE or a specific time from the corresponding LBT timing point. Thereafter, for another UL transmission or acquired transmission power scheduled after initiating the corresponding COT and/or another UL transmission or acquired transmission power scheduled after a timing point at which the UE first performs the LBT or a specific time after the corresponding LBT timing point, or another UL transmission or acquired transmission power scheduled after a timing point at which the ED threshold is determined for the LBT based on transmission power information acquired before the corresponding LBT is performed, it may be necessary to limit the operation that the transmission power of the corresponding another UL transmission exceeds p_max or p_avg for the first ED threshold calculation. For example, although p_new of transmission power configured/indicated for BS to UL #3 is higher than p_max or p_avg, p_new may be limited to p_max or p_avg, and p_new is used only for transmission.

In other words, if p_new, which is a transmission power configured/indicated to UL #3, is higher than p_max or p_avg, UL #3 may be transmitted with the transmission power of p_max or p_avg.

Here, if the transmission times of the respective Tx beams within the COT are the same, the average EIRP may be determined by dividing the sum of EIRP values of the respective Tx beams by the number of beams. For example, when the power in the COT varies in the order of A1, A2, and A3, it can be calculated as p_avg= { a1+a2+a3}/3. Here, A1, A2, and A3 may correspond to Tx beam #1, tx beam #2, and Tx beam #3, respectively, and it is assumed that the time areas occupied by Tx beam #1, tx beam #2, and Tx beam #3 within the COT are the same.

On the other hand, in the above example, if ul#3 is expected to transmit using a power larger than p_max or p_avg of ul#1 and ul#2 used to calculate the ED threshold of the first COT acquisition, the method of embodiment #2-2, embodiment #2-3, or embodiment #2-4 may be applicable.

For example, if LBT is performed using t_ref based on p_max or p_avg as ED threshold to acquire COT first, it is necessary to more sensitively determine whether a channel is BUSY/IDLE using ED threshold t_new relatively lower than t_ref to transmit UL #3 using transmission power p_new greater than p_max or p_avg.

Here, t_new is the ED threshold calculated based on p_new.

In addition, similar to embodiment #2-2, cat-2 LBT is performed by setting the ED threshold to t_new (< t_ref) prior to UL #3 transmission. If successful, the UL #3 transmission may be sent within the first acquired COT.

Alternatively, similar to embodiment #2-3, in addition to the COTs obtained from t_ref based on UL #1 and UL #2 transmission powers, a new COT may be obtained by performing a new LBT (e.g., cat-3 LBT or Cat-4 LBT) on UL #3 having a larger transmission power p_new by t_ref (< t_ref) calculated based on p_new. In addition, in this case, UL #3 may be transmitted within the newly acquired COT.

Alternatively, similar to embodiment #2-4, if p_new, which is the transmission power of UL #3, is greater than p_max or p_avg of UL #1 and UL #2 that have been transmitted after the LBT procedure in COT, the method of not transmitting UL #3 (i.e., UL #3 discard) may be applicable.

According to the above-described embodiment of [ suggested method #2], after performing the operation for COT acquisition, if the UE performs LBT in consideration of EIRP of UL signals considered to be transmitted by the corresponding UE within the COT when LBT is performed, even if another UL signal scheduled within the corresponding COT is identified, EIRP of the corresponding other UL signal is limited, so that interference to another BS/UE can be reduced and fair coexistence between heterogeneous RATs can be achieved.

[ suggested method #3]

The UL COT start timing of the UE is T, and LBT may be performed using an ED threshold calculated from a PUSCH scheduled by a UL grant (e.g., a UL grant of a PUSCH to be included in the same UL COT) and an RRC configured UL signal and channel (e.g., CG-PUSCH, semi-static PUCCH/SRS, and/or semi-persistent PUSCH/PUCCH) included in the same UL COT.

In this case, the value of K may include { n2+α } or { (minimum value of K2 values configured for UE) +α }. Here, the α value may be differently set for each UE according to the capability of the UE, or a specific value (e.g., α=0 symbol, 1 symbol, 0 slot, or 1 slot) may be predefined. Alternatively, a plurality of values may be defined in advance for α, and one of the plurality of values may be set by UE capability and BS signaling.

When the UE receives multiple UL transmission schedules to be transmitted in UL COT from the BS, UL power of each UL transmission may be configured before COT starts. In addition, an ED threshold may be set based on the configured UL power, and LBT may be performed based on the configured ED threshold.

Therefore, it is possible to configure UL transmission power only when N2 time, which is an existing minimum processing time, is basically guaranteed. In addition, since LBT, which calculates ED threshold based on corresponding UL transmission power and determines whether a channel is IDLE/BUSY based on the calculated ED threshold, needs to be performed, additional margin can be secured with minimum processing time.

In other words, when the UE starts LBT from a specific timing point, it may be regarded as a time line for calculating the ED threshold in consideration of UL power of UL signals/channels that may be acquired at the corresponding timing point.

Thus, if the UL COT start timing point of the UE is T, LBT may be performed using an ED threshold calculated from a PUSCH scheduled by a UL grant received before the timing point (T-K) (e.g., a UL grant of a PUSCH to be included in the same UL COT) and an RRC-configured UL signal and channel (e.g., CG-PUSCH, semi-static PUCCH/SRS, and/or semi-persistent PUSCH/PUCCH) included in the same UL COT. In this case, the value of K may include { n2+α } or { (minimum value of K2 values configured for UE) +α }. Here, the α value may be a different value for each UE according to the capability of the UE. Alternatively, a specific value (e.g., α=0 symbol, 1 symbol, 0 slot, or 1 slot) may be predefined. Alternatively, a plurality of values may be defined in advance for α, and one of the plurality of values may be configured by UE capability and BS signaling.

For example, in the above description with respect to fig. 17 (a) to 17 (c), since dci#3 is received or decoded at least after a timing point (T-K), the UE may not consider ul#3 scheduled by dci#3 in calculating the ED threshold.

In addition, for example, in fig. 17 (a) to 17 (c) described above, ul#1 and ul#2 may be scheduled by DCI or include UL signals of RRC configuration, and DCI and/or RRC configuration of scheduled ul#1 and/or ul#2 may be received or decoded before a timing point (T-K) and then reflected in calculation of ED threshold by UE.

On the other hand, depending on the UE implementation, the two operations of UL power setting and { EDT calculation+lbt execution } may be performed in parallel or sequentially. For example, the result of decrementing the back-off counter based on ED threshold a and the result of decrementing the back-off counter based on ED threshold B may be different. In addition, if the UE stores the backoff counter value in the buffer only at each time instant, the two operations may be sequentially performed. In this case, since ED threshold determination should be completed at the LBT start timing point, the margin value α may have to be larger.

As another example, if the UE implementation stores an energy value of the measurement channel at each time instant, the backoff counter value may be calculated back based on the changed value even if the ED threshold is changed later, so in this case, the margin a value may be relatively small.

According to the above proposed method #3, the criteria of the UL signal considered by the UE can be clarified to determine the ED threshold. Thus, the UE can clearly distinguish an UL signal for determining the ED threshold from another UL signal for performing transmission according to the proposed method # 2.

The various descriptions, functions, procedures, proposals, methods and/or operational flowcharts of the present disclosure described herein may be applied to, but are not limited to, various fields in which wireless communication/connectivity (e.g., 5G) between devices is required.

More specific examples will be described below with reference to the accompanying drawings. In the following figures/description, like reference numerals designate identical or corresponding hardware, software or functional blocks unless otherwise indicated.

Fig. 18 illustrates a communication system 1 applied to the present disclosure.

Referring to fig. 18, a communication system 1 applied to the present disclosure includes a wireless device, a BS, and a network. A wireless device is a device that performs communication using a Radio Access Technology (RAT) (e.g., 5G NR (or new RAT) or LTE), also referred to as a communication/radio/5G device. Wireless devices may include, but are not limited to, robots 100a, vehicles 100b-1 and 100b-2, augmented reality (XR) devices 100c, handheld devices 100d, home appliances 100e, ioT devices 100f, artificial Intelligence (AI) devices/servers 400. For example, the vehicles may include vehicles having wireless communication functions, autonomous vehicles, and vehicles capable of performing vehicle-to-vehicle (V2V) communication. Herein, the vehicle may include an Unmanned Aerial Vehicle (UAV) (e.g., an unmanned aerial vehicle). The XR device may include an Augmented Reality (AR)/Virtual Reality (VR)/Mixed Reality (MR) device and may be implemented in the form of a head-mounted device (HMD), head-up display (HUD) mounted in a vehicle, television (TV), smart phone, computer, wearable device, household appliance, digital signage, vehicle, robot, or the like. Handheld devices may include smart phones, smart boards, wearable devices (e.g., smart watches or smart glasses), and computers (e.g., laptop computers). The home appliances may include televisions, refrigerators, washing machines, and the like. IoT devices may include sensors, smart meters, and the like. For example, the BS and network may be implemented as wireless devices, and a particular wireless device 200a may act as a BS/network node for other wireless devices.

The wireless devices 100a to 100f may connect to the network 300 via the BS 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 via the network 300. The network 300 may be configured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g., NR) network. Although the wireless devices 100a to 100f may communicate with each other through the BS 200/network 300, the wireless devices 100a to 100f may perform direct communication (e.g., side link communication) with each other without intervention of the BS/network. For example, vehicles 100b-1 and 100b-2 may perform direct communications (e.g., V2V/vehicle-to-everything (V2X) communications). An IoT device (e.g., a sensor) may perform direct communication with other IoT devices (e.g., sensors) or other wireless devices 100 a-100 f.

Wireless communications/connections 150a, 150b, and 150c may be established between wireless devices 100 a-100 f/BS200 and between BSs 200. Here, wireless communication/connection may be established through various RATs (e.g., 5G NR) such as UL/DL communication 150a, side link communication 150b (or D2D communication), or inter-BS communication 150c (e.g., relay or Integrated Access Backhaul (IAB)), wireless signals may be transmitted and received between wireless devices, between wireless devices and BSs, and between BSs through wireless communication/connections 150a, 150b, and 150c.

Fig. 19 illustrates a wireless device suitable for use in the present disclosure.

Referring to fig. 19, the first wireless device 100 and the second wireless device 200 may transmit wireless signals through various RATs (e.g., LTE and NR). { first wireless device 100 and second wireless device 200} may correspond to { wireless device 100x and BS200} and/or { wireless device 100x and wireless device 100x } of fig. 18.

The first wireless device 100 may include one or more processors 102 and one or more memories 104, and may further include one or more transceivers 106 and/or one or more antennas 108. The processor 102 may control the memory 104 and/or the transceiver 106 and may be configured to implement the descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed in this document. For example, the processor 102 may process the information within the memory 104 to generate first information/signals and then transmit wireless signals including the first information/signals through the transceiver 106. The processor 102 may receive a wireless signal including the second information/signal through the transceiver 106 and then store information obtained by processing the second information/signal in the memory 104. The memory 104 may be connected to the processor 102 and store a plurality of pieces of information related to the operation of the processor 102. For example, the memory 104 may store software code including instructions for performing part or all of the processes controlled by the processor 102 or for performing the descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed in this document. The processor 102 and the memory 104 may be part of a communication modem/circuit/chip designed to implement a RAT (e.g., LTE or NR). The transceiver 106 may be coupled to the processor 102 and transmit and/or receive wireless signals via one or more of the transceivers 108. Each of the transceivers 106 may include a transmitter and/or a receiver. The transceiver 106 may be used interchangeably with a Radio Frequency (RF) unit. In this disclosure, the wireless device may be a communication modem/circuit/chip.

In particular, instructions and/or operations controlled by the processor 102 of the first wireless device 100 and stored in the memory 104 of the first wireless device 100 in accordance with embodiments of the present disclosure will be described.

Although the following operations are described based on control operations of the processor 102 in terms of the processor 102, software code for performing such operations may be stored in the memory 104. For example, in the present disclosure, the at least one memory 104 may be a computer-readable storage medium and may store instructions or programs. The instructions or programs, when executed, may cause at least one processor, operably connected to the at least one memory, to perform operations related to the following operations in accordance with embodiments or implementations of the present disclosure.

For example, processor 102 may determine an Energy Detection (ED) threshold based on at least one first UL signal. For example, processor 102 may determine at least one first UL signal based on [ suggested method #2] and/or [ suggested method #3], and an ED threshold based on the at least one first UL signal, which is referenced to determine the ED threshold.

Processor 102 may perform Listen Before Talk (LBT) based on the ED threshold. In doing so, LBT may be performed based on D-LBT. For example, the corresponding LBT may be performed based on the [ suggested method #1 ]. However, it is not limited by the [ suggested method #1], and any method capable of multiplexing a plurality of Tx beams and transmitting UL signals through the corresponding Tx beams may be used for LBT execution.

Processor 102 may control transceiver 106 to transmit at least one first UL signal and/or a second UL signal within a Channel Occupancy Time (COT) obtained by LBT. For example, at least one first UL signal and/or second UL signal may be determined and transmitted based on [ suggested method #2] and/or [ suggested method #3 ].

As another example, the processor 102 may control the transceiver 106 to receive information for scheduling DL signals. In addition, the processor 102 may control the transceiver 106 to receive DL signals based on the corresponding information. In doing so, the DL signal may be received based on [ suggested method #1 ].

The second wireless device 200 may include one or more processors 202 and one or more memories 204, and may further include one or more transceivers 206 and/or one or more antennas 208. The processor 202 may control the memory 204 and/or the transceiver 206 and may be configured to implement the descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed in this document. For example, the processor 202 may process the information within the memory 204 to generate a third information/signal and then transmit a wireless signal including the third information/signal through the transceiver 206. The processor 202 may receive the wireless signal including the fourth information/signal through the transceiver 106 and then store information obtained by processing the fourth information/signal in the memory 204. The memory 204 may be connected to the processor 202 and store various information related to the operation of the processor 202. For example, memory 204 may store software code including instructions for performing part or all of the processes controlled by processor 202 or for performing the descriptions, functions, procedures, proposals, methods and/or operational flowcharts disclosed in this document. The processor 202 and memory 204 may be part of a communication modem/circuit/chip designed to implement a RAT (e.g., LTE or NR). The transceiver 206 may be coupled to the processor 202 and transmit and/or receive wireless signals via one or more antennas 208. Each of the transceivers 206 may include a transmitter and/or a receiver. The transceiver 206 may be used interchangeably with RF unit. In this disclosure, the wireless device may be a communication modem/circuit/chip.

In particular, instructions and/or operations controlled by the processor 202 of the second wireless device 200 and stored in the memory 204 of the second wireless device 200 in accordance with embodiments of the present disclosure will be described.

Although the following operations are described based on control operations of the processor 202 in terms of the processor 202, software code for performing such operations may be stored in the memory 204. For example, in the present disclosure, the at least one memory 204 may be a computer-readable storage medium and may store instructions or programs. The instructions or programs, when executed, may cause at least one processor, operably connected to the at least one memory, to perform operations related to the following operations in accordance with embodiments or implementations of the present disclosure.

For example, processor 202 may control transceiver 206 to transmit first information for scheduling at least one first UL signal.

Processor 202 may control transceiver 206 to transmit second information for scheduling a second UL signal.

For example, a transmission timing point of the first information for scheduling the at least one first UL signal and/or the second information for scheduling the second UL signal may be determined based on the suggested method #2 and/or the suggested method # 3.

Processor 202 may control transceiver 206 to receive at least one first UL signal and/or a second UL signal. For example, processor 202 may control transceiver 206 to receive at least one first UL signal and/or second UL signal based on [ suggested method #2] and/or [ suggested method #3 ].

As another example, the processor 202 may control the transceiver 206 to perform LBT and transmit information for scheduling DL signals. For example, processor 202 may perform LBT based on [ suggested method #1 ].

Processor 202 may perform LBT for DL signaling. For example, processor 202 may perform LBT based on [ suggested method #1 ]. However, if the DL signal is transmitted within the COT acquired through the LBT performed in the previous step, the corresponding step may be omitted, or a non-random back-off based LBT (e.g., cat-1 LBT or Cat-2 LBT) may be performed. The processor 202 may control the transceiver 206 to transmit the DL signal based on the corresponding information (S1507).

The hardware elements of wireless devices 100 and 200 will now be described in more detail. One or more protocol layers may be implemented by, but are not limited to, one or more processors 102 and 202. For example, one or more processors 102 and 202 may implement one or more layers (e.g., functional layers such as Physical (PHY), media Access Control (MAC), radio Link Control (RLC), packet Data Convergence Protocol (PDCP), RRC, and Service Data Adaptation Protocol (SDAP)). The one or more processors 102 and 202 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 flowcharts disclosed in this document. The one or more processors 102 and 202 may generate and provide messages, control information, data, or information to the one or more transceivers 106 and 206 in accordance with the descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed in this document. The one or more processors 102 and 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document and provide the generated signals to the one or more transceivers 106 and 206. The one or more processors 102 and 202 may receive signals (e.g., baseband signals) from the one or more transceivers 106 and 206 and obtain PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods, and/or operational flowcharts disclosed in this document.

The one or more processors 102 and 202 may be referred to as a controller, microcontroller, microprocessor, or microcomputer. The one or more processors 102 and 202 may be implemented in 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 the one or more processors 102 and 202. The descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in this document may be implemented using firmware or software, and the firmware or software may be configured to include modules, procedures or functions. Firmware or software configured to perform the descriptions, functions, procedures, proposals, methods and/or operational flow diagrams disclosed in this document may be included in the one or more processors 102 and 202 or may be stored in the one or more memories 104 and executed by the one or more processors 102 and 202. The descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in this document can be implemented using firmware or software in the form of codes, instructions and/or instruction sets.

One or more memories 104 and 204 may be coupled to one or more processors 102 and 202 and store various types of data, signals, messages, information, programs, code, instructions, and/or commands. One or more of the memories 104 and 204 may be configured to include read-only memory (ROM), random-access memory (RAM), electrically erasable programmable read-only memory (EPROM), flash memory, a hard drive, registers, a cache memory, a computer-readable storage medium, and/or combinations thereof. The one or more memories 104 and 204 may be located internal and/or external to the one or more processors 102 and 202. The one or more memories 104 and 204 may be connected to the one or more processors 102 and 202 by various techniques, such as a wired or wireless connection.

One or more transceivers 106 and 206 may transmit the user data, control information, and/or wireless signals/channels referred to in the methods and/or operational flow diagrams of this document to one or more other devices. One or more transceivers 106 and 206 may receive the user data, control information, and/or wireless signals/channels mentioned in the description, descriptions, functions, procedures, proposals, methods, and/or operational flowcharts disclosed in this document from one or more other devices. For example, one or more transceivers 106 and 206 may be coupled to one or more processors 102 and 202 and transmit and receive wireless signals. For example, the one or more processors 102 and 202 may perform control such that the one or more transceivers 106 and 206 transmit user data, control information, or wireless signals to one or more other devices. The one or more processors 102 and 202 may perform control such that the one or more transceivers 106 and 206 are capable of receiving user data, control information, or wireless signals from one or more other devices. One or more transceivers 106 and 206 may be connected to one or more antennas 108 and 208, and one or more transceivers 106 and 206 may be configured to transmit and receive the user data, control information, and/or wireless signals/channels mentioned in the descriptions, functions, procedures, suggestions disclosed in this document through one or more antennas 108 and 208. In this document, the one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). The one or more transceivers 106 and 206 may convert received wireless signals/channels, etc., from RF band signals to baseband signals for processing the received user data, control information, and wireless signals/channels using the one or more processors 102 and 202. The one or more transceivers 106 and 206 may convert the user data, control information, wireless signals/channels processed using the 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 comprise (analog) oscillators and/or filters.

Fig. 28 illustrates a vehicle or autonomous driving vehicle applied to the present disclosure. The vehicle or autonomous driving vehicle may be implemented as a mobile robot, a car, a train, a person/unmanned Aerial Vehicle (AV), a ship, or the like.

Referring to fig. 28, the vehicle or autonomous driving vehicle 100 may include an antenna unit 108, a communication unit 110, a control unit 120, a driving unit 140a, a power supply unit 140b, a sensor unit 140c, and an autonomous driving unit 140d. The antenna unit 108 may be configured as part of the communication unit 110.

The communication unit 110 may transmit and receive signals (e.g., data and control signals) to and from external devices such as other vehicles, BSs (e.g., gNB and roadside units), and servers. The control unit 120 may perform various operations by controlling elements of the vehicle or the autonomous vehicle 100. The control unit 120 may include an ECU. The driving unit 140a may cause the vehicle or the autonomous vehicle 100 to drive on a road. The drive unit 140a may include an engine, an electric motor, a powertrain, wheels, brakes, steering, and the like. The power supply unit 140b may supply power to the vehicle or the autonomous vehicle 100, and may include a wired/wireless charging circuit, a battery, and the like. The sensor unit 140c may acquire information about vehicle state information, surrounding environment information, user information, and the like. The sensor unit 140c may include an Inertial Measurement Unit (IMU) sensor, a collision sensor, a wheel sensor, a speed sensor, a gradient sensor, a weight sensor, a heading sensor, a position module, a vehicle forward/backward sensor, a battery sensor, a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, a humidity sensor, an ultrasonic sensor, an illuminance sensor, a pedal position sensor, and the like. The autonomous driving unit 140d may implement a technique for maintaining a lane on which the vehicle is driven, a technique for automatically adjusting a speed such as adaptive cruise control, a technique for autonomously driving along a determined path, a technique for driving by automatically setting a path if a destination is set, and the like.

For example, the communication unit 110 may receive map data, traffic information data, and the like from an external server. The autonomous driving unit 140d may generate an autonomous driving route and a driving plan from the obtained data. The control unit 120 may control the driving unit 140a such that the vehicle or the autonomous vehicle 100 may move along the autonomous driving route according to a driving plan (e.g., speed/direction control). During autonomous driving, the communication unit 110 may acquire recent traffic information data from an external server aperiodically/aperiodically, and may acquire surrounding traffic information data from a neighboring vehicle. During autonomous driving, the sensor unit 140c may obtain information about vehicle state information and/or ambient information. The autonomous driving unit 140d may update the autonomous driving route and the driving plan based on the newly obtained data/information. The communication unit 110 may transmit information about the vehicle position, the autonomous driving route, and/or the driving plan to an external server. The external server may predict traffic information data using AI technology or the like based on information collected from the vehicle or the autonomous driving vehicle, and provide the predicted traffic information data to the vehicle or the autonomous driving vehicle.

The embodiments of the present disclosure described below are combinations of elements and features of the present disclosure. These elements or features may be considered optional unless specified otherwise. Each element or feature may be practiced without being combined with other elements or features. Additionally, embodiments of the disclosure may be constructed by combining elements and/or portions of features. The order of operations described in embodiments of the present disclosure may be rearranged. Some configurations of any one embodiment may be included in another embodiment and may be replaced by corresponding configurations of the other embodiment. It will be apparent to those skilled in the art that claims that are not explicitly cited in each other in the appended claims may be presented in combination as embodiments of the present disclosure or may be included as new claims by subsequent amendment after the application is filed.

In the present disclosure, in some cases, a specific operation described as being performed by the BS may be performed by an upper node of the BS. That is, it is apparent that in a network composed of a plurality of network nodes including a BS, various operations performed for communication with an MS may be performed by the BS or network nodes other than the BS. The term "BS" may be replaced with the terms "fixed station", "node B", "enhanced node B (eNodeB or eNB)", "access point", etc.

Those skilled in the art will appreciate that the present disclosure can be carried out in other specific ways than those herein set forth without departing from the spirit and essential characteristics of the disclosure. The above embodiments are therefore to be construed in all aspects as illustrative and not restrictive. The scope of the present disclosure should be determined by the appended claims and their legal equivalents, rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the appended claims are intended to be embraced therein.

Although the above-described method of transmitting and receiving signals in an unlicensed band and apparatus thereof have been described based on an example applied to a 5G NR system, the method and apparatus are applicable to various wireless communication systems in addition to a 5GNR system.

Claims

1. A method of transmitting an Uplink (UL) signal by a User Equipment (UE) in a wireless communication system, the method comprising:

determining an Energy Detection (ED) threshold based on a maximum effective isotropic correlation power (EIRP) among at least one first EIRP for at least one first UL signal;

acquiring channel occupancy based on the ED threshold; and

within the channel occupancy, (i) transmitting the at least one first UL signal based on each of the at least one first EIRP for each of the at least one first UL signal, and (ii) transmitting a second UL signal based on a second EIRP,

Wherein the second EIRP is equal to or less than the maximum EIRP.

2. The method of claim 1, wherein the second UL signal is disregarded in determining the ED threshold.

3. The method of claim 1, wherein the scheduling information for the at least one first UL signal is received before the scheduling information for the second UL signal is received.

4. The method of claim 1, wherein the second EIRP is equal to the maximum EIRP based on the EIRP for the second UL signal being greater than the maximum EIRP.

5. The method of claim 1, wherein the channel occupancy is obtained based on a success of Listen Before Talk (LBT) based on the ED threshold.

6. The method of claim 1, wherein the at least one first UL signal and the second UL signal are transmitted through UL Tx beams that are different from each other.

7. The method of claim 1, wherein the at least one first UL signal and the second UL signal are transmitted over a frequency band above 52.6 GHz.

8. A user equipment transmitting an Uplink (UL) signal in a wireless communication system, the user equipment comprising:

At least one transceiver;

at least one processor; and

at least one memory operably connected to the at least one processor and configured to store instructions for enabling the at least one processor to perform operations when executed,

wherein the operations include: determining an Energy Detection (ED) threshold based on a maximum effective isotropic correlation power (EIRP) among at least one first EIRP for at least one first UL signal; acquiring channel occupancy based on the ED threshold; and within the channel occupancy, (i) transmitting the at least one first UL signal based on each of the at least one first EIRP for each of the at least one first UL signal, and (ii) transmitting a second UL signal based on a second EIRP, and

wherein the second EIRP is equal to or less than the maximum EIRP.

9. The user equipment of claim 8, wherein the second UL signal is disregarded in determining the ED threshold.

10. The user equipment of claim 8, wherein the scheduling information for the at least one first UL signal is received before the scheduling information for the second UL signal is received.

11. The user equipment of claim 8, wherein the second EIRP is equal to the maximum EIRP based on an EIRP for the second UL signal being greater than the maximum EIRP.

12. The user equipment of claim 8, wherein the channel occupancy is acquired based on a success of Listen Before Talk (LBT) based on the ED threshold.

13. The user equipment of claim 8, wherein the at least one first UL signal and the second UL signal are transmitted through UL Tx beams different from each other.

14. The user equipment of claim 8, wherein the at least one first UL signal and the second UL signal are transmitted over a frequency band above 52.6 GHz.

15. An apparatus for transmitting an Uplink (UL) signal in a wireless communication system, the apparatus comprising:

at least one processor; and

Wherein the second EIRP is equal to or less than the maximum EIRP.

16. A computer-readable storage medium comprising at least one computer program configured to cause at least one processor to perform operations,

wherein the second EIRP is equal to or less than the maximum EIRP.