Patent Application
20250183980
The disclosure relates to a wireless communication system, and more particularly, to a method and device for configuring a beam for repeater in a wireless communication system.
5th generation (5G) mobile communication technologies define broad frequency bands such that high transmission rates and new services are possible, and can be implemented not only in “Sub 6 gigahertz (GHz)” bands such as 3.5 GHz, but also in “Above 6 GHz” bands referred to as millimeter wave (mmWave) including 28 GHz and 39 GHz. In addition, it has been considered to implement 6th generation (6G) mobile communication technologies (referred to as Beyond 5G systems) in terahertz (THz) bands (for example, 95 GHz to 3 THz bands) in order to accomplish transmission rates fifty times faster than 5G mobile communication technologies and ultra-low latencies one-tenth of 5G mobile communication technologies.
At the beginning of the development of 5G mobile communication technologies, in order to support services and to satisfy performance requirements in connection with enhanced mobile broadband (eMBB), ultra-reliable low-latency communications (URLLC), and massive machine-type communications (mMTC), there has been ongoing standardization regarding beamforming and massive multiple input multiple output (MIMO) for mitigating radio-wave path loss and increasing radio-wave transmission distances in mmWave, supporting various numerologies (for example, operating multiple subcarrier spacings, etc.) for efficiently utilizing mmWave resources and dynamic operation of slot formats, initial access technologies for supporting multi-beam transmission and broadbands, definition and operation of bandwidth part (BWP), new channel coding methods such as a low density parity check (LDPC) code for large amount of data transmission and a polar code for highly reliable transmission of control information, L2 pre-processing, and network slicing for providing a dedicated network specialized to a specific service.
Currently, there are ongoing discussions regarding improvement and performance enhancement of initial 5G mobile communication technologies in view of services to be supported by 5G mobile communication technologies, and there has been physical layer standardization regarding technologies such as vehicle-to-everything (V2X) for aiding driving determination by autonomous vehicles based on information regarding positions and states of vehicles transmitted by the vehicles and for enhancing user convenience, new radio unlicensed (NR-U) aimed at system operations conforming to various regulation-related requirements in unlicensed bands, new radio (NR) user equipment (UE) power saving, non-terrestrial network (NTN) which is UE-satellite direct communication for providing coverage in a region in which communication with terrestrial networks is unavailable, and positioning.
Moreover, there has been ongoing standardization in air interface architecture/protocol regarding technologies such as industrial internet of things (IIoT) for supporting new services through interworking and convergence with other industries, integrated access and backhaul (JAB) for providing a node for network service area expansion by supporting a wireless backhaul link and an access link in an integrated manner, mobility enhancement including conditional handover and dual active protocol stack (DAPS) handover, and two-step random access for simplifying random access procedures (2-step random access channel (RACH) for NR). There also has been ongoing standardization in system architecture/service regarding a 5G baseline architecture (for example, service based architecture or service based interface) for combining Network Functions Virtualization (NFV) and Software-Defined Networking (SDN) technologies, and Mobile Edge Computing (MEC) for receiving services based on UE positions.
As 5G mobile communication systems are commercialized, connected devices that have been exponentially increasing will be connected to communication networks, and it is accordingly expected that enhanced functions and performances of 5G mobile communication systems and integrated operations of connected devices will be necessary. To this end, new research is scheduled in connection with eXtended Reality (XR) for efficiently supporting Augmented Reality (AR), Virtual Reality (VR), Mixed Reality (MR) and the like, 5G performance improvement and complexity reduction by utilizing Artificial Intelligence (AI) and Machine Learning (ML), AI service support, metaverse service support, and drone communication.
Furthermore, such development of 5G mobile communication systems will serve as a basis for developing not only new waveforms for providing coverage in terahertz bands of 6G mobile communication technologies, multi-antenna transmission technologies such as Full Dimensional MIMO (FD-MIMO), array antennas and large-scale antennas, metamaterial-based lenses and antennas for improving coverage of terahertz band signals, high-dimensional space multiplexing technology using Orbital Angular Momentum (OAM), and Reconfigurable Intelligent Surface (RIS), but also full-duplex technology for increasing frequency efficiency of 6G mobile communication technologies and improving system networks, AI-based communication technology for implementing system optimization by utilizing satellites and AI from the design stage and internalizing end-to-end AI support functions, and next-generation distributed computing technology for implementing services at levels of complexity exceeding the limit of UE operation capability by utilizing ultra-high-performance communication and computing resources.
The disclosure provides a method for determining, by a base station, a beam that a repeater transmits and receive to and from a terminal in case where there is a repeater between the base station and the terminal in a wireless communication system, and the repeater amplifies and transmits a signal or channel provided from the base station to the terminal.
In order to solve the above problems, the disclosure may provide a method performed by a repeater in a wireless communication system comprising receiving control information from a base station, wherein the control information includes information associated with a beam for a signal to be transmitted from the repeater to a terminal, receiving a signal from the base station, and transmitting the signal, received from the base station, to the terminal based on the beam.
In addition, a method performed by a base station in a wireless communication system according to an embodiment of the disclosure may comprise transmitting control information to a repeater, wherein the control information includes information associated with a beam for a signal to be transmitted from the repeater to a terminal, transmitting a signal to the repeater, wherein the signal, which has been transmitted to the repeater, may be delivered to the terminal through the repeater based on the beam.
In addition, a repeater in a wireless communication system according to an embodiment of the disclosure may comprise a receiver configured to receive control information from a base station and receive a signal from the base station, and a transmitter, wherein the control information may include information associated with a beam for a signal to be transmitted from the repeater to a terminal, and wherein the transmitter may be configured to transmit the signal, received from the base station, to the terminal based on the beam.
In addition, a base station in a wireless communication system according to an embodiment of the disclosure may comprise a controller, and a transceiver configured to transmit control information to a repeater and transmit a signal to the repeater, wherein the control information may include information associated with a beam for a signal to be transmitted from the repeater to a terminal, and the signal, which has been transmitted to the repeater, may be delivered to the terminal through the repeater on the basis of the beam.
According to an embodiment of the disclosure, beamforming gain can be obtained in case where a repeater amplifies and transmits under the control of a base station in a wireless communication system.
Hereinafter, embodiments of the disclosure will be described in detail with reference to the accompanying drawings.
In the following description of embodiments of the disclosure, descriptions of techniques that are well known in the art and not directly related to the disclosure are omitted. This is to clearly convey the gist of the disclosure by omitting any unnecessary explanation.
For the same reason, some elements in the drawings are exaggerated, omitted, or schematically illustrated. Also, actual sizes of respective elements are not necessarily represented in the drawings. In the drawings, the same or corresponding elements are denoted by the same reference numerals.
The advantages and features of the disclosure and ways to achieve them will be apparent by making reference to embodiments as described below in detail in conjunction with the accompanying drawings. However, the disclosure is not limited to the embodiments set forth below, but may be implemented in various different forms. The following embodiments are provided only to completely disclose the disclosure and inform those skilled in the art of the scope of the disclosure, and the disclosure is defined only by the scope of the appended claims. Throughout the specification, the same or like reference numerals designate the same or like elements.
Herein, it will be understood that each block of the flowchart illustrations, and combinations of blocks in the flowchart illustrations, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart block(s). These computer program instructions may also be stored in a computer usable or computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer usable or computer-readable memory produce an article of manufacture including instruction means that implement the function specified in the flowchart block(s). The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable data processing apparatus to produce a computer implemented process such that the instructions that execute on the computer or other programmable data processing apparatus provide steps for implementing the functions specified in the flowchart block(s).
Further, each block of the flowchart illustrations may represent a module, segment, or portion of code, which includes one or more executable instructions for implementing the specified logical function(s). It should also be noted that in some alternative implementations, the functions noted in the blocks may occur out of the order. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved.
As used herein, the “unit” refers to a software element or a hardware element, such as a Field Programmable Gate Array (FPGA) or an Application Specific Integrated Circuit (ASIC), which performs a predetermined function. However, the “unit” does not always have a meaning limited to software or hardware. The “unit” may be constructed either to be stored in an addressable storage medium or to execute one or more processors. Therefore, the “unit” includes, for example, elements such as software elements, object-oriented software elements, class elements or task elements, processes, functions, properties, procedures, sub-routines, segments of a program code, drivers, firmware, micro-codes, circuits, data, database, data structures, tables, arrays, and parameters. The elements and functions provided by the “unit” may be either combined into a smaller number of elements and a “unit”, or divided into a larger number of elements and a “unit”. Moreover, the elements and “units” or may be implemented to reproduce one or more central processing units (CPUs) within a device or a security multimedia card. Further, the “unit” in the embodiments may include one or more processors.
Hereinafter, the operation principle of the disclosure will be described in detail with reference to the accompanying drawings. In describing the disclosure, a detailed description of known functions or configurations incorporated herein will be omitted when it is determined that the description may make the subject matter of the disclosure unnecessarily unclear. The terms which will be described below are terms defined in consideration of the functions in the disclosure, and may be different according to users, intentions of the operators, or customs. Therefore, the definitions of the terms should be made based on the contents throughout the specification.
Hereinafter, a base station is an entity that allocates resources to terminals, and may be at least one of a gNode B, an eNode B, a Node B, a base station (BS), a wireless access unit, a base station controller, and a node on a network. A terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smartphone, a computer, or a multimedia system capable of performing communication functions. It is apparent that examples of the base station and the terminal are not limited thereto.
The following description of the disclosure is directed to technology for receiving broadcast information from a base station by a terminal in a wireless communication system. The disclosure relates to a communication technique for converging Internet of Things (IoT) technology with a 5th generation (5G) communication system designed to support a higher data transfer rate beyond the 4th generation (4G) system, and a system therefor. The disclosure may be applied to intelligent services (e.g., smart homes, smart buildings, smart cities, smart cars or connected cars, healthcare, digital education, retail business, security and safety-related services, etc.) on the basis of 5G communication technology and IoT-related technology.
In the following description, terms with reference to broadcast information, terms with reference to control information, terms related to communication coverage, terms with reference to state changes (e.g., events), terms with reference to network entities, terms with reference to messages, terms with reference to device elements, and the like are illustratively used for the sake of convenience. Therefore, the disclosure is not limited by the terms as used below, and other terms with reference to subjects having equivalent technical meanings may be used.
In the following description, some of terms and names defined in the 3rd generation partnership project long term evolution (3GPP LTE) standards may be used for the convenience of description. However, the disclosure is not limited by these terms and names, and may be applied in the same way to systems that conform other standards.
Wireless communication systems have been developed from wireless communication systems providing voice centered services to broadband wireless communication systems providing high-speed, high-quality packet data services, such as communication standards of high speed packet access (HSPA), long-term evolution (LTE or evolved universal terrestrial radio access (E-UTRA)), LTE-advanced (LTE-A), and LTE-Pro of the 3GPP, high rate packet data (HRPD) and ultra-mobile broadband (UMB) of 3GPP2, 802.16e of IEEE, and the like.
An LTE system that is a representative example of the broadband wireless communication system has adopted an orthogonal frequency division multiplexing (OFDM) scheme in a downlink (DL) and has adopted a single carrier frequency division multiple access (SC-FDMA) scheme in an uplink (UL). The UL refers to a wireless link through which a terminal (UE or MS) transmits data or a control signal to a base station (BS or eNodeB), and the DL refers to a wireless link through which a base station transmits data or a control signal to a terminal. The multiple access scheme normally allocates and operates time-frequency resources for transmission of data or control information according to each user so as to prevent the time-frequency resources from overlapping with each other, that is, to establish orthogonality, thereby distinguishing the data or control information of each user.
As a future communication system after LTE, that is, a 5G communication system has to be able to freely reflect various requirements of a user, service provider, etc., and thus services satisfying various requirements need to be supported. The services considered for the 5G communication system include enhanced mobile broadband (eMBB), massive machine-type communication (mMTC), ultra-reliability low latency communication (URLLC), and the like.
According to some embodiments, eMBB aims to provide a higher data transmission rate than a data transmission rate supported by the LTE, LTE-A, or LTE-Pro. For example, in the 5G communication system, eMBB should be able to provide a peak data rate of 20 Gbps in the DL and a peak data rate of 10 Gbps in the UL from the viewpoint of one base station. At the same time, the 5G communication system should provide the increased user perceived data rate of the terminal. In order to satisfy such requirements, improvement of various transmitting/receiving technologies including a further improved multiple input multiple output (MIMO) transmission technology is needed. In addition, the 5G communication system uses a bandwidth wider than 20 megahertz (MHz) in a frequency band of 3 to 6 GHz or more than 6 GHz, instead of a 2 GHz band used by the current LTE, thereby satisfying a data transmission rate required in the 5G communication system.
Simultaneously, mMTC is being considered to support application services such as Internet of Thing (IoT) in the 5G communication system. mMTC is required for an access support of a large-scale terminal in a cell, coverage enhancement of a terminal, improved battery time, and cost reduction of a terminal in order to efficiently provide the IoT. The IoT needs to be able to support a large number of terminals (e.g., 1,000,000 terminals/km2) in a cell because it is attached to various sensors and devices to provide communication functions. In addition, because the terminals supporting mMTC are more likely to be positioned in shaded regions not covered by a cell, such as a basement of a building due to nature of services, the terminals may require a wider coverage than other services provided by the 5G communication system. The terminals supporting mMTC should be configured as inexpensive terminals and require very long battery life-time because it is difficult to frequently replace batteries of the terminals.
Finally, URLLC is a cellular-based wireless communication service used for mission-critical purposes, and the URLLC may consider a service used in remote control for robots or machinery, industrial automation, unmanned aerial vehicles, remote health care, emergency alerts, and the like. Accordingly, the URLLC should provide very low latency and very high reliability. For example, URLLC-supportive services need to meet an air interface latency of less than 0.5 milliseconds and simultaneously include requirements of a packet error rate of 10−5 or less. Accordingly, for URLLC-supportive services, the 5G system should provide a transmit time interval (TTI) shorter than those for other services while securing design requirements for allocating a broad resource in a frequency band. However, the aforementioned mMTC, URLLC, and eMBB are only examples of different service types, and the service types to which the disclosure is applied are not limited to the above-described examples.
The above-discussed services considered in the 5G communication system should be converged with each other and provided, based on a single framework. That is, for an effective resource management and control, it is desirable that such services are controlled and transmitted by being integrated into one system rather than being operated independently.
In addition, although an embodiment of the disclosure will be described below using an LTE, LTE-A, LTE Pro, or NR system as an example, the embodiment of the disclosure may be applied to other communication systems having similar technical backgrounds or channel types. In addition, an embodiments of the disclosure may be applied to other communication systems through some modifications within a range which does not significantly depart from the scope of the disclosure, as determined by a person having skilled technical knowledge.
Hereinafter, the frame structure of a 5G system will be described in more detail with reference to the drawings.
With reference to
With reference to
In NR, one component carrier (CC) or serving cell may include up to 250 RBs or more. Therefore, in case that a UE always receives the entire serving cell bandwidth, such as in the LTE system, power consumption of the UE may be extreme, and in order to solve this problem, it is possible for a base station to configure one or more bandwidth parts (BWPs) for the UE so as to support the UE to change a reception region within a cell. In NR, the base station may configure an “initial BWP”, which is a bandwidth of control resource set (CORESET) #0 (or common search space (CSS)), for the UE via a master information block (MIB). Thereafter, the base station may configure an initial BWP (first BWP) of the UE via radio resource control (RRC) signaling, and may notify of at least one BWP configuration information that can be indicated through downlink control information (DCI) in the future. Thereafter, the base station may notify of a BWP ID via DCI so as to indicate which band the UE is to use. In case that the UE fails to receive DCI in a currently allocated BWP for a specific period of time or more, the UE returns to a “default BWP” and attempts to receive DCI.
With reference to
An embodiment of the disclosure is not limited to the above example, and in addition to the configuration information, various parameters related to a BWP may be configured in the UE. The above-described pieces of information may be delivered by the base station to the UE via higher layer signaling, for example, RRC signaling. At least one BWP among the configured one or multiple BWPs may be activated. Whether to activate the configured BWP may be semi-statically delivered from the base station to the UE via RRC signaling or may be dynamically delivered through an MAC control element (CE) or DCI.
According to an embodiment, a UE before RRC connection may be configured with an initial BWP for initial access from a base station through a MIB. More specifically, the UE may receive configuration information about a search apace and a control resource set (or CORESET) through which the physical downlink control channel (PDCCH) can be transmitted, in order to receive system information required for initial access (which may correspond to remaining system information (RMSI) or system information block 1 (SIB 1)) through the MIB in an initial access operation. Each of the control resource set (CORESET) and search space configured through the MIB may be regarded as identity (ID) 0.
The base station may notify the UE of configuration information, such as frequency allocation information, time allocation information, and numerology for the control resource set #0 through the MIB. In addition, the base station may notify the UE of configuration information regarding the monitoring periodicity and occasion for the control resource set #0, that is, configuration information regarding the search space #0, through the MIB. The UE may regard the frequency domain configured as the control resource set #0, obtained from the MIB, as an initial BWP for initial access. Here, the identity (ID) of the initial BWP may be regarded as zero.
The configuration of the BWP supported by the above-described next-generation mobile communication system (5G or NR system) may be used for various purposes.
As an example, in case that a bandwidth supported by the UE is smaller than a system bandwidth, the bandwidth supported by the UE may be supported through the BWP configuration. For example, in Table 2, a frequency location (configuration information 2) of the BWP is configured for the UE and thus the UE may transmit or receive data at a specific frequency location within the system bandwidth.
According to another example, the base station may configure multiple BWPs in the UE for the purpose of supporting different numerologies. For example, in order to support both data transmission/reception to/from a predetermined UE by using a subcarrier spacing of 15 kilohertz (kHz) and a subcarrier spacing of 30 kHz, two BWPs may be configured to use a subcarrier spacing of 15 kHz and a subcarrier spacing of 30 kHz, respectively. Different BWPs may be frequency division multiplexed (FDMed), and in case of desiring to transmit or receive data at a specific subcarrier spacing, the BWP configured with the corresponding subcarrier spacing may be activated.
According to still another example, the base station may configure, in the UE, BWPs having bandwidths of different sizes for the purpose of reducing power consumption of the UE. For example, in case that the UE supports a very large bandwidth, for example, a bandwidth of 100 MHz, and always transmits or receives data through the corresponding bandwidth, very large power consumption may occur. In particular, in a situation in which there is no traffic, it is very inefficient, in terms of power consumption, for the UE to monitor an unnecessary downlink control channel for a large bandwidth of 100 MHz. Therefore, for the purpose of reducing power consumption of the UE, the base station may configure, for the UE, a bandwidth part of a relatively small bandwidth, for example, the bandwidth part of 20 MHz. In a situation in which there is no traffic, the UE may perform a monitoring operation in the bandwidth part of 20 MHz. In case that data has been generated, the UE may transmit or receive the data by using the bandwidth part of 100 MHz according to an indication of the base station.
In a method of configuring the bandwidth part, the UEs before the RRC connection may receive configuration information about the initial bandwidth part through the MIB in the initial access operation. More specifically, the UE may be configured with a control resource set (or CORESET) for a downlink control channel, through which DCI for scheduling a system information block (SIB) may be transmitted, from a MIB of a physical broadcast channel (PBCH). The bandwidth of the control resource set configured through the MIB may be regarded as the initial BWP. The UE may receive a physical downlink shared channel (PDSCH), through which the SIB is transmitted, through the configured initial BWP. The initial BWP may be used for other system information (OSI), paging, and random access in addition to the reception of the SIB.
Hereinafter, a synchronization signal (SS)/PBCH block (SSB) of a next generation mobile communication system (5G or NR system) will be described.
The SS/PBCH block may refer to a physical layer channel block including a primary SS (PSS), a secondary SS (SSS), and a PBCH. More specifically, the SS/PBCH block may be defined as follows:
The UE may detect the PSS and the SSS in the initial access operation, and may decode the PBCH. The UE may acquire the MIB from the PBCH, and may be configured with the control resource set #0 through the MIB. The UE may monitor the control resource set #0 under the assumption that the selected SS/PBCH block and a demodulation reference signal (DMRS) transmitted in the control resource set #0 are quasi-co-located (QCLed). The UE may receive system information through downlink control information transmitted from the control resource set #0. The UE may acquire, from the received system information, random access channel (RACH)-related configuration information required for initial access. The UE may transmit a physical RACH (PRACH) to the base station by considering the selected SS/PBCH index, and the base station having received the PRACH may acquire information about an SS/PBCH block index selected by the UE. The base station may know which block is selected, by the UE, among the SS/PBCH blocks, and may know that the UE has monitored the control resource set #0 corresponding to (or associated with) the selected SS/PBCH block.
Subsequently, downlink control information (hereinafter referred to as DCI) in a next generation mobile communication system (5G or NR system) is described in detail.
In the next generation mobile communication system (5G or NR system), scheduling information for uplink data (or a physical uplink shared channel (a PUSCH)) or downlink data (or a physical downlink shared channel (a PDSCH)) is delivered from the base station to the UE through DCI. The UE may monitor a fallback DCI format and non-fallback DCI format for the PUSCH or the PDSCH. The fallback DCI format may include a fixed field predefined between the base station and the UE, and the non-fallback DCI format may include a configurable field.
The DCI may be transmitted through a PDCCH, which is a physical downlink control channel, via a channel coding and modulation process. A cyclic redundancy check (CRC) may be added to a DCI message payload and may be scrambled by a radio network temporary identifier (RNTI) corresponding to the identity of the UE. Depending on the purpose of the DCI message, for example, UE-specific data transmission, a power control command, or a random access response, different RNTIs may be used for scrambling of the CRC added to the DCI message payload. That is, the RNTI is not explicitly transmitted but is included in a CRC calculation process to be transmitted. If the DCI message transmitted through the PDCCH is received, the UE may identify the CRC through the allocated RNTI. If the CRC identification result is correct, the UE may recognize that the corresponding message is transmitted to the UE.
For example, DCI for scheduling a PDSCH for system information (SI) may be scrambled by an SI-RNTI. DCI for scheduling a PDSCH for a random access response (RAR) message may be scrambled by a RA-RNTI. DCI for scheduling a PDSCH for a paging message may be scrambled by a P-RNTI. DCI for notifying of a slot format indicator (SFI) may be scrambled by an SFI-RNTI. DCI for notifying of transmit power control (TPC) may be scrambled with a TPC-RNTI. DCI for scheduling a UE-specific PDSCH or PUSCH may be scrambled by a cell RNTI (C-RNTI).
DCI format 0_0 may be used for fallback DCI for scheduling a PUSCH in which case the CRC may be scrambled by a C-RNTI. DCI format 0_0 in which the CRC is scrambled by the C-RNTI may include, for example, the following information shown below in Table 3.
DCI format 0_1 may be used for non-fallback DCI for scheduling a PUSCH in which case the CRC may be scrambled by a C-RNTI. In an embodiment, DCI format 0_1 in which the CRC is scrambled by the C-RNTI may include, for example, the following information shown below in Table 4.
DCI format 1_0 may be used for fallback DCI for scheduling a PDSCH in which case the CRC may be scrambled by a C-RNTI. In an embodiment, DCI format 1_0 in which the CRC is scrambled by the C-RNTI may include, for example, the following information shown below in Table 5.
Alternatively, DCI format 1_0 may be used as DCI for scheduling a PDSCH for a RAR message in which case the CRC may be scrambled by a RA-RNTI. DCI format 1_0 in which the CRC is scrambled by the C-RNTI may include, for example, the following information shown below in Table 6.
DCI format 1_1 may be used for non-fallback DCI for scheduling a PDSCH in which case the CRC may be scrambled by a C-RNTI. In an embodiment, DCI format 1_1 in which the CRC is scrambled by the C-RNTI may include, for example, the following information shown below in Table 7.
In the wireless communication system, one or more different antenna ports (alternatively, it may be replaced with one or more channels, signals, and combinations thereof, but in future descriptions of the disclosure, they are collectively referred to as different antenna ports for convenience of description) may be associated by a QCL configuration shown in Table 10, below. The TCI state is to inform of a QCL relation between a PDCCH (or a PDCCH DMRS) and another RS or channel, and a reference antenna port A (e.g., reference RS #A) and another purpose antenna port B (e.g., target RS #B) which are QCLed means that the UE is allowed to apply some or all of large-scale channel parameters estimated in the antenna port A to channel measurement from the antenna port B. The QCL is required to associate different parameters according to conditions, such as 1) time tracking influenced by average delay and delay spread, 2) frequency tracking influenced by Doppler shift and Doppler spread, 3) radio resource management (RRM) influenced by an average gain, and 4) beam management (BM) influenced by a spatial parameter. Accordingly, NR supports four types of QCL relations shown in Table 8, below.
The above spatial Rx parameter may collectively refer to some or all of various parameters such as an angle of arrival (AoA), a power angular spectrum (PAS) of AoA, an angle of departure (AoD), a PAS of AoD, a transmission/reception channel correlation, transmission/reception beamforming, and a spatial channel correlation.
The QCL relation may be configured in the UE through RRC parameter TCI-state and QCL-Info as shown in Table 9, below. With reference to Table 9, the base station may configure one or more TCI states in the UE and inform the UE of a maximum of two QCL relations (QCL-Type 1 and QCL-Type 2) for an RS with reference to an ID of the TCI state, that is, a target RS. In this case, each piece of the QCL information (QCL-Info) included in the TCI state includes a serving cell index and BWP index of a reference RS indicated by the corresponding QCL information, a type and an ID of the reference RS, and the QCL type as shown in Table 8, above.
In the following, the QCL priority determination operation for the PDCCH will be described in detail.
The UE may select a specific control resource set according to the QCL priority determination operation and monitor control resource sets having the same QCL-TypeD characteristics as the corresponding control resource set, in case that the UE operates with carrier aggregation within a single cell or band and a plurality of control resource sets existing within an activated bandwidth part within a single or plurality of cells have the same or different QCL-TypeD characteristics in a specific PDCCH monitoring interval and overlap each other in time. That is, when a plurality of control resource sets overlap in time, only one QCL-TypeD characteristic may be received. In this case, the criteria for determining the QCL priority may be as follows.
As described above, the next criterion is applied in case that each of the above criteria is not satisfied. For example, in case that control resource sets overlap in time in a specific PDCCH monitoring duration, if all control resource sets are not connected to a common search space but connected to a UE-specific search period, that is, if criteria 1 is not satisfied, the UE may omit the application of criteria 1 and apply criteria 2.
In case of selecting a control resource set based on the above criteria, the UE may additionally consider the following two items for QCL information configured to the control resource set. First, in case that control resource set 1 has CSI-RS 1 as a reference signal having a QCL-TypeD relationship, and a reference signal that this CSI-RS 1 has a QCL-TypeD relationship is SSB 1, and a reference signal that another control resource set 2 has a QCL-TypeD relationship is SSB 1, the UE may consider these two control resource sets 1 and 2 to have different QCL-TypeD characteristics. Second, in case that control resource set 1 has CSI-RS 1 configured in cell 1 as a reference signal having a QCL-TypeD relationship, and a reference signal that this CSI-RS 1 has a QCL-TypeD relationship is SSB 1, control resource set 2 has CSI-RS 2 configured in cell 2 as a reference signal having a QCL-TypeD relationship and a reference signal that this CSI-RS 2 has a QCL-TypeD relationship is SSB 1, the UE may consider the two control resource sets to have the same QCL-TypeD characteristics.
With reference to
A base station may configure the above described control resource set in the 5G for a terminal through higher layer signaling (e.g., system information, an MIB or RRC signaling). To configure the control resource set for the terminal means that information, such as a control resource set identity, a frequency location of the control resource set, a symbol length of the control resource set, etc. are provided.
With reference to
With reference to
The basic unit of the downlink control channel shown in
The UE needs to detect a signal in a state in which the UE does not know information about the downlink control channel, and a search space indicating a set of CCEs may be defined for blind decoding. The search space is a set of downlink control channel candidates including CCEs that the UE has to attempt to decode at a given aggregation level. Since there are various aggregation levels that make one bundle of 1, 2, 4, 8, or 16 CCEs, the UE may have a plurality of search spaces. A search space set may be defined as a set of search spaces at all configured aggregation levels.
The search space may be classified into a common search space and a UE-specific search space. According to an embodiment of the disclosure, a predetermined group of UEs or all the UEs may examine the common search space of the PDCCH in order to receive cell common control information, such as dynamic scheduling of system information or a paging message.
For example, the UE may receive PDSCH scheduling allocation information for transmission of the SIB including cell operator information and the like by examining the common search space of the PDCCH. In a case of the common search space, since a predetermined group of UEs or all the UEs need to receive the PDCCH, the common search space may be defined as a set of previously promised CCEs. On the other hand, the UE may receive scheduling allocation information about the UE-specific PDSCH or PUSCH by examining the UE-specific search space of the PDCCH. The UE-specific search space may be UE-specifically defined as a function of the UE identity and various system parameters.
In 5G, the parameter for the search space of the PDCCH may be configured for the UE from the base station via higher layer signaling (e.g., SIB, MIB, and RRC signaling). For example, the base station may configure, in the UE, the number of PDCCH candidates at each aggregation level L, the monitoring periodicity for the search space, monitoring occasion of symbol units in the slots for the search space, the search space type (common search space or UE-specific search space), a combination of RNTI and DCI format to be monitored in the corresponding search space, a control resource set index to monitor the search space, and the like. For example, the configuration information described above may include the following pieces of information of Table 10 below.
The base station may configure one or a plurality of search space sets for the UE based on configuration information. According to an embodiment of the disclosure, The base station may configure search space set 1 and search space set 2 in the UE, configure DCI format A scrambled by X-RNTI in the search space set 1 to be monitored in the common search space, and configure DCI format B scrambled by Y-RNTI in the search space set 2 to be monitored in a UE-specific search space.
According to the configuration information, one or a plurality of search space sets may exist in the common search space or UE-specific search space. For example, search space set #1 and search space set #2 may be configured as the common search space, and search space set #3 and search space set #4 may be configured as the UE-specific search space.
The common search space may be classified into a search space set of a specific type according to a purpose. An RNTI to be monitored may be different according to the determined type of search space set. For example, the common search space type, purpose, and RNTI to be monitored may be classified as Table 10a below.
PDCCH
SI
(SIB2
PDCCH
, Msg4
PDCCH
,
Meanwhile, in the common search space, the following combinations of the DCI format and RNTI may be monitored. However, the disclosure is not limited thereto.
In the UE-specific search space, the following combinations of the DCI format and RNTI may be monitored. However, the disclosure is not limited thereto.
The specified RNTIs may follow the definitions and usages described below.
Cell RNTI (C-RNTI): For UE-specific PDSCH scheduling
Temporary Cell RNTI (TC-RNTI): For UE-specific PDSCH scheduling
Configured Scheduling RNTI (CS-RNTI): For semi-statically configured UE-specific PDSCH scheduling
Random Access RNTI (RA-RNTI): For PDSCH scheduling in random access operation
Paging RNTI (P-RNTI): For scheduling of PDSCH through which paging is transmitted
System Information RNTI (SI-RNTI): For PDSCH scheduling in which system information is transmitted
Interruption RNTI (INT-RNTI): For notifying of whether to puncture PDSCH
Transmit Power Control for PUSCH RNTI (TPC-PUSCH-RNTI): For indication of power control command for PUSCH
Transmit Power Control for PUCCH RNTI (TPC-PUCCH-RNTI): For indication of power control command for PUCCH
Transmit Power Control for SRS RNTI (TPC-SRS-RNTI): For indication of power control command for SRS
In an embodiment, the above-described DCI formats may be defined as shown in Table 11 below.
According to an embodiment of the disclosure, in 5G, a plurality of search space sets may be configured with different parameters (e.g., parameters in Table 10). Accordingly, the set of search space sets monitored by the UE may differ at each time point. For example, in case that search space set #1 is configured with a X-slot period, search space set #2 is configured with a Y-slot period, and X and Y are different, the UE may monitor both search space set #1 and space set #2 in a specific slot, and may monitor one of search space set #1 and search space set #2 in a specific slot.
In case that a plurality of search space sets are configured for the UE, the following conditions may be considered in order to determine a search space set to be monitored by the UE.
The number of PDCCH candidates that may be monitored per slot may not exceed Mμ. The Mμ may be defined as the maximum number of PDCCH candidates per slot in a cell configured to a subcarrier spacing of 15·2μ kHz, and may be defined as shown in Table 12 below.
The number of CCEs configuring the entire search space per slot (here, the entire search space may denote the entire set of CCEs corresponding to a union region of a plurality of search space sets) may not exceed Cμ. The Cμ may be defined as the maximum number of CCEs per slot in a cell configured to a subcarrier spacing of 15·2μ kHz, and may be defined as shown in Table 13 below.
For the convenience of description, a situation in which both conditions 1 and 2 are satisfied at a specific time point is defined as “condition A”. Therefore, not satisfying condition A may refer to not satisfying at least one of the above conditions 1 and 2.
According to the configuration of the search space sets of the base station, a case in which condition A is not satisfied at a specific time point may occur. In case that condition A is not satisfied at a specific time point, the UE may select and monitor only some of the search space sets configured to satisfy condition A at a corresponding time point, and the base station may transmit PDCCH to the selected search space sets.
According to an embodiment of the disclosure, a method for selecting some search spaces from the entire configured search space set may conform to the following method.
In case that condition A for PDCCH is not satisfied at a specific time point (slot),
The UE (or base station) may prioritize the selection of a search space set, in which a search space type is configured as a common search space, from among search space sets existing at a corresponding time point, than a search space set in which a search space type is configured as a UE-specific search space.
In case that all search space sets configured as common search spaces are selected (i.e., in case that condition A is satisfied even after all search spaces configured as common search spaces are selected), the UE (or base station) may select the search space sets configured as UE-specific search spaces. Here, in case that there are a plurality of search space sets configured as the UE-specific search spaces, a search space set having a low search space set index may have a higher priority. In consideration of the priority, the UE or base station may select the UE-specific search space sets within a range in which condition A is satisfied.
Methods of allocating time and frequency resources for data transmission in NR are described below.
In NR, the following detailed frequency domain resource allocation (FD-RA) methods may be provided in addition to frequency domain resource candidate allocation through BWP indication.
With reference to
In case that the UE is configured to use only resource type 1 via higher layer signaling (6-05), some DCI for allocation of the PDSCH to the UE includes frequency domain resource allocation information configured by ┌log2(NRBDL,BWP(NRBDL,BWP+1)/2┐ bits. Conditions for this will be described again later. Through this information, the base station may figure a starting VRB 6-20 and the length of frequency domain resources 6-25 continuously allocated therefrom.
In case that the UE is configured to use both resource type 0 and resource type 1 via higher layer signaling (6-10), some DCI for allocation of PDSCH to the corresponding UE includes frequency domain resource allocation information configured by bits of a greater value 6-35 among a payload 6-15 for configuration of resource type 0 and payloads 6-20 and 6-25 for configuration of resource type 1. Conditions for the above configuration will be described later. Here, one bit may be added to the most significant bit (MSB) of the frequency domain resource allocation information in the DCI, in case that the corresponding bit has a value of 0, it may indicate that resource type 0 is used; in case that the corresponding bit has a value of 1, it may indicate that resource type 1 is used.
Hereinafter, a method for allocating time domain resources for a data channel in a next-generation mobile communication system (5G or NR system) will be described.
A base station may configure, for a UE, a table for time domain resource allocation information for a downlink data channel (PDSCH) and an uplink data channel (PUSCH) via higher layer signaling (e.g., RRC signaling). With regard to PDSCH, a table including maxNrofDL-Allocations=16 entries may be configured, and with regard to PUSCH, a table including maxNrofUL-Allocations=16 entries may be configured. In an embodiment, the time domain resource allocation information may include PDCCH-to-PDSCH slot timing (corresponding to a time gap in slot units between a time point of receiving a PDCCH and a time point of transmitting a PDSCH scheduled by the received PDCCH, and denoted as K0), PDCCH-to-PUSCH slot timing (corresponding to a time gap in slot units between a time point of receiving a PDCCH and a time point of transmitting a PUSCH scheduled by the received PDCCH, and denoted as K2), information on the position and length of a start symbol for which the PDSCH or PUSCH is scheduled within a slot, a mapping type of PDSCH or PUSCH, and the like. For example, the base station may notify the UE of information such as Table 15 or Table 16 below.
The base station may notify the UE of one of the entries in the above-described table regarding the time domain resource allocation information to via L1 signaling (e.g., DCI) (e.g., may be indicated by a “time domain resource allocation” field in DCI). The UE may acquire time domain resource allocation information for the PDSCH or PUSCH based on the DCI received from the base station.
With reference to
With reference to
Next, a beam configuration method in which a base station transmits control information and data to a UE will be described. In the disclosure, for convenience of explanation, a process of transmitting control information through a PDCCH may be expressed as transmitting the PDCCH, and a process of transmitting data through a PDSCH may be expressed as transmitting the PDSCH.
First, a beam configuration method for a PDCCH will be described.
With reference to
Next, a beam configuration method for a PDSCH will be described.
With reference to
The meaning of each field in the MAC CE and values configurable for each field are as follows.
In case of receiving DCI format 1_1 or DCI format 1_2, the UE may receive a PDSCH through one beam of the TCI states activated by the MAC-CE based on information of a transmission configuration indication (TCI) field in DCI (10-40). Whether the TCI field exists is determined by a tci-PresentinDCI value, which is a higher layer parameter in a CORESET configured for reception of the DCI. If tci-PresentinDCI is configured to “enabled” in the higher layer, the UE may identify the TCI field of 3 bits information to determine TCI states activated according to a DL BWP or a scheduled component carrier and the direction of a beam linked to DL-RS.
Coverage is an important factor in a wireless communication system. 5G is currently being commercialized and mmWave is also included in the commercialization. However, due to the limited coverage, there is not much actual use. Many service providers are looking for a method for economically operating communication systems while providing stable coverage at the same time. Service providers may consider installing multiple base stations, but the high cost has led them to look for a more cost-effective method.
For this reason, the first technology considered is an integrated access and backhaul (JAB), which has been studied over Rel-16 and Rel-17. The IAB is a kind of relay that does not require a wired backhaul network, and performs relaying of signals between a base station and a UE. The IAB has a similar performance to that of a base station, to thereby having the disadvantage of increasing costs.
Second, conventional RF repeaters may be considered. The RF repeaters are the most basic unit of repeater, which amplify a received signal and transmit the amplified signal. The RF repeaters have the advantage of being inexpensive because they perform amplification and transmission simply, but they cannot actively respond to various situations. As an example, the RF repeaters typically use omni antennas rather than directional antennas, and thus beamforming gain cannot be obtained. In addition, the RF repeaters may be a source of interference because they amplify and transmit noise even in case that there are no terminals connected to the RF repeater.
The IABs and RF repeaters show that their advantages and disadvantages are biased in terms of performance and cost. In order to realistically increase coverage, not only performance but also cost should be considered, and thus the need for a new terminal or amplifier is emerging.
Currently, in 3GPP Rel-18, research is underway on a network-controlled repeater that maintains the simple amplification and transmission operation of the RF repeater and enables beamforming technology with an adaptive antenna. For convenience of description, the network-controlled repeater will be referred to as NetRep hereinafter. However, the use of these terms does not limit the technical scope of the disclosure. In order for the NetRep to transmit a signal to the UE by using an adaptive antenna within a base station cell, the NetRep should be able to receive a control signal from a base station. Therefore, NetRep may include repeater-mobile termination (MT) and repeater-radio unit (RU) similar to IAB. The repeater-MT may communicate like a typical UE from the viewpoint of the base station. On the other hand, the repeater-RU includes only the basic RF or physical layer and may perform transmission and reception operations using an adaptive antenna under base station control. In addition to transmitting and receiving operations using adaptive antennas, the NetRep may also perform dynamic TDD configurations, on/off or power control for interference control.
The NetRep may basically amplify the signal transmitted from the base station and transmit the amplified signal to the UE, and may transmit the signal transmitted from the UE to the base station. Therefore, the NetRep may amplify and transmit signals or channels transmitted and received between the base station and the terminal without detecting or decoding the signals or channels. Therefore, from the point of view of the UE, the NetRep between the base station and the UE is not visible. In other words, the UE is unable to distinguish between the base station and the NetRep, and the NetRep may appear to be a base station. Since the UE does not need any additional information or operation for the NetRep, a UE supporting any release may be supported by the NetRep.
As described above, from the point of view of the base station, the NetRep may be seen as a general type of UE. In case that the NetRep is first installed, the NetRep may perform an initial access to the base station like a general terminal, and after a higher layer connection is established, may receive a configuration that a UE would normally receive. The NetRep may perform an operation of amplifying a signal or channel and transmitting the amplified signal or channel after being connected to the base station. From the point of view of the base station, it is necessary to know whether the UE is directly connected to the base station or connected through the NetRep. In case that the UE is within the coverage of the NetRep, the UE may communicate with the base station through the NetRep, and the base station may recognize this through its implementation.
The base station may know which UE performs communication through which NetRep, but the NetRep is unable to know this fact. Regardless of whether a UE is located within its coverage or not, the NetRep may perform an operation of amplifying a signal and transmitting the amplified signal to the UE under the control of the base station. In order for the base station to control the NetRep, a control signal that plays a similar role to that of the DCI may be required. In the disclosure, this control signal is defined as side control information (SCI) for convenience. However, the use of these terms does not limit the technical scope of the disclosure. The SCI may refer to a control channel transmitted by the base station to control the NetRep, and is an unknown signal from the point of view of the UE, and may be recognized only by the base station and the NetRep. The SCI is not limited to the terms described in this disclosure, and other terms having equivalent technical meanings, such as repeater-DCI (R-DCI), repeater control information (RCI), etc. In order for the NetRep to dynamically use an adaptive antenna through the SCI, it is necessary to define when and which spatial antenna parameters to use.
The existing TCI state framework may be viewed as a way to designate for a base station to designate SSB or CSI-RS as a QCL source and to inform the UE of information that the base station transmits using the same beam as the corresponding QCL source. For example, if the base station configures 64 SSBs and indicates the UE to use SSB #1 and a TCI state that it is QCLed, the UE may prepare for reception in response to the spatial parameters of the antenna used by the base station for SSB #1.
For example, in a link between the base station and a repeater (base station-repeater link), like an existing UE, the NetRep receives an indication of the existing TCI state from the base station and may receive a signal or channel transmitted by the base station using the spatial parameters of the corresponding antenna.
However, since the existing TCI state framework uses the base station's SSB or CSI-RS as a QCL source, it may not be applicable to a link between the repeater and the UE (repeater-UE link). From the point of view of NetRep, it may be difficult to use the existing TCI state framework because the spatial parameters of the antenna used when transmitting in the UE direction cannot use the QCL source of the base station.
Therefore, the disclosure proposes an R-TCI state framework that allows the base station to simply configure/indicate the spatial parameters of the repeater's antenna. Here, the R-TCI state is illustrated for convenience. The R-TCI state refers to the index of the spatial parameters of the antenna used in case that the NetRep transmits and receives to the UE, and may have a similar meaning to QCL-Type D of the existing TCI state. Accordingly, the disclosure is not limited to the terms to be described later, and other terms having equivalent technical meaning may be used.
As an example of methods to apply the R-TCI state, when the repeater reports to the base station the number of spatial parameter sets of available antennas or the number of resources available as sources of QCL-Type D, the base station may provide mapping as shown in Table 19 below to the repeater through higher layer signaling. As another example, without reporting from the repeater, the base station may provide mapping as shown in Table 19 below to the repeater through higher layer signaling.
Table 19 is an example to describe a mapping relationship between the R-TCI state and QCL source that may be configured in the repeater.
The QCL source in Table 19 may indicate a signal amplified and transmitted by the repeater among the signals/channels received from the base station. Here, the signal may include a cell-specific signal that is configured together across all cells of the base station. The R-TCI state is not recognized from the viewpoint of the UE, and may only be recognized between the base station and the repeater. Therefore, the base station provides the configurations in [Table 19] to the repeater. When the UE reports to the base station that it has reference signal received power (RSRP) with the highest SSB #0 value, it may be seen that the repeater has performed amplification and transmission using the antenna space parameters corresponding to R-TCI #0. The base station may activate or deactivate the R-TCI state in [Table 19] using MAC-CE.
With reference to
The base station may configure a signal or channel commonly configured within a cell for the UE. For example, the base station may commonly configure information about the SSB for all UEs within the cell. The NetRep may receive a signal or channel commonly configured within the cell of the base station. In this case, the NetRep may share the same configurations as the UE. In case that the NetRep amplifies and transmits a cell-specific signal, time information may be known, and antenna spatial parameters may be determined by the implementation of the NetRep. Here, the meaning that it may be determined by implementation includes the meaning that the NetRep implementation determines which antenna spatial parameters will be applied to the cell-specific signal. For example, if R-TCI #0 in Table 19, which may be provided through a higher layer from the base station, is mapped to SSB #0, the NetRep may know that the antenna spatial parameter used when amplifying and transmitting SSB #0 is referred to as R-TCI #0, but the antenna spatial parameters actually used may be applied by the implementation of the NetRep. Alternatively, the base station may configure the antenna spatial parameters corresponding to the R-TCI state of the mapping configured in Table 19 through higher layer configurations.
Even if mapping information such as Table 19 is not provided, the NetRep may amplify and transmit cell-specific signals by implementation.
The base station may configure a UE-specific signal or channel for the UE within the cell. For example, the base station may configure a UE-specific search space for the UE and provide a UE-specific PDCCH to the UE. Further, if the control information includes a data resource, the UE may receive the PDSCH. In this case, the UE may receive QCL information for control information and data information from the base station. For example, QCL information about PDCCH may be configured through MAC-CE, and QCL information about PDSCH may be obtained through activation/deactivation configurations via MAC-CE and through indications via DCI. Since the above operations are all UE-specific configurations, the NetRep may not recognize the operations unless the base station separately configures the operations for the NetRep. If the base station configures information about all UEs within coverage for the NetRep, the NetRep may recognize the signals and channels previously configured by a higher layer and amplify and transmit the signals and channels with the corresponding QCL. However, from the point of view of the NetRep, which cannot decode control information and data information transmitted to the UE, there is a limitation in that the NetRep cannot recognize resources dynamically allocated to the UE. Therefore, in case that the base station dynamically transmits signals and channels to the UE through the NetRep, there is a need to first indicate the NetRep on which time resource and which antenna spatial parameter to use.
With reference to
The first operation (12-01) is a method in which the R-TCI state 12-04 indicated by the base station to the NetRep through the SCI 12-02 is time-constrained. For example, the NetRep that did not receive any SCI in 12-01 may initially use a default R-TCI state 12-03 for amplification and transmission. Here, the NetRep may expect to receive the default R-TCI configurations through a higher layer (e.g., RRC or MAC-CE). In case that there is no higher layer configuration, it may operate as a NetRep implementation. If the NetRep detects an SCI including R-TCI, the NetRep may perform amplification and transmission by applying the antenna spatial parameters corresponding to the indicated R-TCI state in the indicated time resource, and may return to the default R-TCI and perform amplification and transmission when the indicated time resource ends. If the default R-TCI state is not configured, the NetRep may no longer perform amplification and transmission operations after amplification and transmission based on the indicated R-TCI state in the indicated time resource are completed. For example, if the indicated R-TCI state ends at n symbols, the NetRep may not perform amplification and transmission operations starting from n+1 symbols.
The second operation (12-11) is a method in which the R-TCI state 12-04 indicated by the base station to the NetRep through the SCI 12-12 has no time constraints. For example, the NetRep that did not receive any SCI in 12-11 may initially use the default R-TCI state 12-03 for amplification and transmission. Here, the NetRep may expect to receive the default R-TCI configurations through a higher layer (e.g., RRC or MAC-CE). In case that there is no higher layer configuration, it may operate as NetRep implementation. If the NetRep detects an SCI including the R-TCI state, the NetRep may perform amplification and transmission by applying antenna spatial parameters corresponding to the indicated R-TCI state in the indicated time resource. The indicated time resource may not have information about the duration of the R-TCI state, or even if the duration exists, it may not be applied. The indicated R-TCI may be maintained until an SCI including a new R-TCI state is indicated. If the default R-TCI state is not configured, the NetRep may no longer perform amplification and transmission operations after amplification and transmission based on the indicated R-TCI state in the indicated time resource are completed. For example, if the indicated R-TCI state ends at n symbols, the NetRep may not perform amplification and transmission operations starting from n+1 symbols.
The above distinct operations (12-01, 12-11) are provided for illustrative purposes, but they are not mutually exclusive and may be applied in appropriate combination with each other depending on the situation.
In the above embodiment, the SCIs 12-02 and 12-12 may be detected based on the configurations of common search space (CSS) or UE specific search space (USS). If CSS is configured, the NetRep may be provided with the RNTI used when monitoring the PDCCH including the corresponding DCI format. For example, the RNTI may be configured with a NetRep-only RNTI, but is not limited thereto. In addition, the position and payload size corresponding to the NetRep configured within the field in the corresponding DCI format may be configured through higher layer parameters. If USS is configured, the NetRep may be provided with the RNTI (e.g., C-RNTI) used when monitoring the PDCCH of the corresponding DCI format.
A detected SCI may be expected to include at least the following information. However, this is only an example, and SCI elements are not limited to the above elements.
The SCI element including the R-TCI state may include at least the following information:
In the above information, the slot offset may indicate the slot to which R-TCI will be applied on the basis of the slot including the detected SCI. The time resource may expect a start and length indicator value (SLIV) for the 12-01 method, and may indicate the SLIV or start symbol for the 12-11 method. In case that 12-01 and 12-11 are used interchangeably, if the SLIV is included, it may indicate the 12-01 operation, and in case that there is a start symbol, it may indicate the 12-11 operation.
It may need time to prepare decoding time or related antenna operation until the NetRep detects/acquires the SCI and performs the R-TCI state indication operation described above. Therefore, at least X symbols may be required between the last symbol of SCI and the first symbol to which the R-TCI state is applied. For example, the X may be configured by the base station to the NetRep through higher layer signaling (e.g., RRC) on the basis of a NetRep's capability report. Alternatively, even without the capability report, the base station may configure the X for the NetRep through higher layer signaling (e.g., RRC).
According to the embodiment described in the second embodiment, in case that the NetRep needs to change the antenna spatial parameters several times, the base station needs to indicate SCI each time. This may be a necessary operation in case that a signal or channel needs to be dynamically transmitted/received to/from the UE. However, in the case of static transmission/reception to/from the UE, detecting multiple SCIs to change multiple antenna spatial parameters consumes unnecessary resources and may increase network overhead when operating the NetRep. Here, statically transmission and reception may include a case where resources have already been determined, such as CSI-RS or SPS PDSCH. In the above case, by configuring time resources and R-TCI corresponding to the NetRep through a higher layer (e.g., RRC) and dynamically indicating SCI if necessary, the advantage of reducing overhead may be obtained. Therefore, in case that time resources and corresponding R-TCI may be configured in advance, an operation of indicating multiple R-TCI states with one SCI may be required. In addition, even in case that the NetRep may use one or more panels that operate independently from each other, an operation of receiving an indication for multiple R-TCI states with one SCI may be required.
<Situation 1: A Case where Only One Individual Panel Exists>
Hereinafter, a method for indicating an R-TCI state with different time resources in case that there is only one panel in the NetRep will be described. An embodiment to be described is based on the assumption of Situation 2 in the second embodiment.
With reference to
The first operation (13-01) is a method in which the R-TCI state 13-04 indicated by the base station to NetRep through the SCI 13-02 is time-constrained. For example, the NetRep that did not receive any SCI in operation 13-01 may initially use a default R-TCI state 13-03 to perform amplification and transmission. Here, the NetRep may expect to receive a default R-TCI configuration through a higher layer (e.g., RRC or MAC-CE). If there is no higher layer configuration, it may operate as a NetRep implementation. If the NetRep detects an SCI including an R-TCI with one or more time resources, the NetRep may perform amplification and transmission by applying antenna spatial parameters corresponding to the indicated R-TCI in the indicated time resource, and may return to the default R-TCI and perform amplification and transmission when the indicated time resource ends.
For example, in the first operation (13-01), a plurality of R-TCI states indicated based on the SCI may correspond to time resources configured in element order of the set of R-TCI states. For example, resource 1, resource 2, resource 3, and resource 4 are configured in time order in the time domain. In case that based on the SCI, R-TCI #0, R-TCI #1, R-TCI #2, R-TCI #3 are indicated, resource 1-R-TCI #0, resource 2-R-TCI #1, resource 3-R-TCI #2, and resource 4-R-TCI #3 may correspond, respectively. In addition, in case that a time gap exists between respective resources, the default R-TCI may be applied in the time gap.
For example, in case that the number of configured resources is greater than the number of R-TCI states, the R-TCI may be applied in a cyclic shift method. In case that there are more R-TCI states than the number of configured resources, the R-TCI states that are not corresponded may be ignored.
If the default R-TCI state is not configured, the NetRep may no longer perform amplification and transmission operations after amplification and transmission based on the indicated R-TCI states in the indicated time resource are completed. For example, if the indicated R-TCI state ends at n symbols, the NetRep may not perform amplification and transmission operations starting from n+1 symbols.
The second operation (13-11) is a method in which the R-TCI state 13-04 indicated by the base station to the NetRep through the SCI 13-12 has no time constraints. For example, the NetRep that did not receive any SCI in operation 13-11 may initially use the default R-TCI state 13-03 to perform amplification and transmission. Here, the NetRep may expect to receive the default R-TCI configuration through a higher layer (e.g., RRC or MAC-CE). In case that there is no higher layer configuration, it may operate as a NetRep implementation. If the NetRep detects an SCI including an R-TCI with one or more time resources, the NetRep may perform amplification and transmission by applying antenna spatial parameters corresponding to the indicated R-TCI in the indicated time resource. The indicated time resource may not have information about duration, or may not be applied even if duration exists. The indicated R-TCI may be maintained until an SCI including a new R-TCI state is indicated.
For example, in the second operation (13-11), a plurality of R-TCI states indicated based on the SCI may correspond to time resources configured in element order of the set of R-TCI states. For example, resource 1, resource 2, resource 3, and resource 4 are configured in time order in the time domain. In case that based on the SCI, R-TCI #0, R-TCI #1, R-TCI #2, R-TCI #3 are indicated, resource 1-R-TCI #0, resource 2-R-TCI #1, resource 3-R-TCI #2, and resource 4-R-TCI #3 may correspond, respectively. In addition, the R-TCI state applied in response to a specific resource may remain valid until a new resource is started.
For example, if the number of configured resources is greater than the number of R-TCI states, R-TCI may be applied in a cyclic shift method. In case that there are more R-TCI states than the number of configured resources, the R-TCI states that are not corresponded may be ignored.
If the default R-TCI state is not configured, the NetRep may no longer perform amplification and transmission operations after amplification and transmission based on the indicated R-TCI state in the indicated time resource are completed. For example, if the indicated R-TCI state ends at n symbols, the NetRep may not perform amplification and transmission operations starting from n+1 symbols.
The above distinct operations (13-01, 13-11) are provided for illustrative purposes, but they are not mutually exclusive and may be applied in appropriate combination with each other depending on the situation.
In the above embodiment, the SCIs 13-02 and 13-12 may be detected based on the configuration of CSS or USS. If CSS is configured, the NetRep may be provided with the RNTI used when monitoring the PDCCH including the corresponding DCI format. For example, the RNTI may be configured with a NetRep-only RNTI, but is not limited thereto. In addition, the position and payload size corresponding to the NetRep configured within the fields in the DCI format may be configured through higher layer parameters. If USS is configured, the NetRep may be provided with the RNTI (e.g., C-RNTI) used when monitoring the PDCCH of the corresponding DCI format.
The detected SCI may be expected to include at least the following information. However, this is only an example, and SCI elements are not limited to the above elements.
An SCI element including an R-TCI state with one or more time resources may include at least the following information:
The R-TCI state set list field and TDRA set list field of the above information may indicate codepoints in Table 20 and Table 21 below, respectively. However, this is only an example of one embodiment, and its use may be indicated by other fields with equivalent technical meaning. The R-TCI state set list and TDRA set list may be provided to the NetRep through a higher layer (e.g., RRC). Here, the R-TCI state set list may be expected to include at least the information shown in Table 20 below.
Table 20 is an example of an R-TCI state set list according to an embodiment of the disclosure.
The left column in Table 20 represents the Codepoint, and its use may be indicated by SCI's R-TCI state set list field or another field with equivalent technical meaning. The right column represents the R-TCI state set corresponding to the codepoint. {R-TCI #0, R-TCI #1, R-TCI #2, R-TCI #3} in the R-TCI state set means a set of R-TCI state IDs or may be a set of information corresponding thereto. The R-TCI state set may include one or more R-TCI state IDs. Information corresponding to Table 20 above may be provided by a higher layer (RRC).
The TDRA set list may be expected to include at least the information shown in Table 21 below.
Table 21 is an example of a TDRA set list according to an embodiment of the disclosure.
The left column in Table 21 represents the Codepoint, and its use may be indicated by SCI's TDRA set list field or another field with equivalent technical meaning. The right column represents the TDRA set corresponding to the codepoint. {TDRA #0, TDRA #1, TDRA #2, TDRA #3} in the TDRA set means a set of TDRA IDs or may be a set of information corresponding thereto. A TDRA set may include one or more TDRA IDs.
Here, in operation 13-01, TDRA may include at least the following information:
In the above information, the slot offset may indicate the slot to which R-TCI will be applied based on the slot including the detected SCI. Further, in case that the SLIV is provided, it may include both start symbol and duration information like existing SLIV. In case that the bitmap method is applied, the NetRep may be provided with a bitmap of a specific length (e.g., 14 bit string), and it may be seen that the R-TCI state is applied where the bit is ‘1’, and is not applied where the bit is ‘0’.
Meanwhile, in operations 13-11, TDRA may include at least the following information:
In the above information, the slot offset may indicate the slot to which the R-TCI will be applied based on the slot including the detected SCI. Further, in case that the SLIV is provided, it may include both the start symbol and information about the duration like the existing SLIV, but only the start symbol is applied and the information about the duration may be ignored. In case that the bitmap method is provided, a bitmap of a specific bit length (e.g., 14 bit string) is provided, and it may be seen that this is the start symbol to which the R-TCI state is applied where the bit is ‘1’. It may be seen that it is not the start symbol where the bit is ‘0’. If the start symbol index is provided, it may be seen that the R-TCI state starts from the corresponding start symbol.
In case that the 13-01 operation and the 13-11 operation are used interchangeably, if SLIV or bit map is included, it may indicate the 13-01 operation, and in case that only the start symbol is included, the 13-11 operation may be indicated.
<Situation 2: A Case where One or More Panels Exist>
Hereinafter, a method for indicating an R-TCI state with different time resources in case that one or more panels exist in the NetRep will be described. Here, it is assumed that different panels may operate independently and simultaneous transmission is possible. An embodiment to be described is based on the assumption of Situation 2 in the second embodiment.
With reference to
The first operation (14-01) is the same as the operation 13-01 described in Situation 1, but the difference is that the first operation may be applied to each panel. Here, default R-TCI states 14-03 and 14-04 applied to panel #1 (14-03) and applied to panel #2 (14-04) may be the same or different. The NetRep may expect to receive the default R-TCI state configuration through a higher layer (e.g., RRC or MAC-CE). In case that there is no higher layer configuration, it may operate as NetRep implementation.
The second operation (14-11) is the same as the operation 13-11 described in Situation 1, but the difference is that the second operation may be applied to each panel. The default R-TCI state is the same as the operation described previously.
The above distinct operations (14-01, 14-11) are provided for illustrative purposes, but they are not mutually exclusive and may be applied in appropriate combination with each other depending on the situation.
In the above embodiment, the SCIs 14-02 and 14-12 may be detected based on the configuration of CSS or USS. If CSS is configured, the NetRep may be provided with the RNTI used when monitoring the PDCCH including the corresponding DCI format. For example, the RNTI may be configured with a NetRep-only RNTI, but is not limited thereto. In addition, the position and payload size corresponding to the NetRep configured within the fields in the DCI format may be configured with higher layer parameters. If USS is configured, the NetRep may be provided with the RNTI (e.g., C-RNTI) used when monitoring the PDCCH of the corresponding DCI format.
The detected SCI may be expected to include at least the following information. However, this is only an example, and SCI elements are not limited to the above elements.
For the NetRep supporting N panels, the base station may transmit an SCI including the following information to the NetRep. For example, an SCI element including one or more time resources and one or more R-TCI states may include at least the following information:
The SCI element may include a panel identity (ID), an R-TCI state (set) corresponding to the panel identity, and a TDRA set. In the above information, N may mean the number of panels that the NetRep may support. The R-TCI state set list field and TDRA set list field included as the elements in each panel may respectively indicate the codepoints in Table 20 and Table 21 described in <Situation 1>. Further, the same operation as described in Situation 1 may be expected independently for each panel.
Meanwhile, the NetRep may not expect that the SCI always includes information about N panels. Therefore, even if the NetRep supports N panels, information corresponding to N or less panels may be configured in SCI.
The above-described embodiments and/or methods may be performed separately, or two or more embodiments or methods may be combined and performed together. In addition, when performing some embodiments, methods of other embodiments may be referenced/used.
A signaling procedure in
In addition, a repeater in
With reference to
For example, the control information may include information associated with a beam for a signal to be transmitted from the repeater to the UE. The information associated with the beam may include at least one of information about a time resource, a slot offset, and an identity associated with the beam. The information about the time resource may include a start symbol and duration.
At least one beam for a signal to be transmitted from the repeater to the UE may be configured on the basis of the information associated with the beam. For example, in case that a plurality of beams are configured, each beam may correspond to a different time resource. The different time resources and plurality of different beams may correspond sequentially.
In operation S1520, the base station may transmit a signal (or channel, information, etc.) to the repeater. That is, the repeater may receive signals from the base station. The signal may include information for the base station to deliver to the UE through the repeater.
In operation S1530, the repeater may transmit the signal received from the base station to the UE. That is, the UE may receive a signal from the repeater. The repeater may perform the process of amplifying the signal received from the base station in S1525 before operation S1530 and transmit the amplified signal to the UE.
Here, the repeater may transmit a signal to the UE based on the beam indicated by information associated with the beam in the control information. For example, the repeater may identify the information about the time resource and the identity associated with the beam based on the information associated with the beam. Thereafter, the repeater may transmit, to the UE, the signal received from the base station within the time resource using the beam corresponding to the identity associated with the beam. Outside (after) the time resource, the repeater may not perform amplification and transmission. The beam indicated by the information associated with the beam may mean spatial parameters or QCL information applied to the link between the repeater and the UE.
The above-described embodiments and/or methods and signaling procedure in
With reference to
The UE receiver 16-00 and UE transmitter 16-10 may be collectively called a transceiver. According to the communication method of the UE described above, the UE receiver 16-00, UE transmitter 16-10, and UE processor 16-05 of the UE may operate. However, the elements of the UE are not limited to the above-described examples. For example, the UE may include more or fewer elements (e.g., a memory and the like) than the aforementioned elements. In addition, the UE receiver 16-00, UE transmitter 16-10, and UE processor 16-05 may be implemented in the form of a single chip.
The UE receiver 16-00 and UE transmitter 16-10 (or transceiver) may transmit or receive a signal to or from a base station. Here, the signal may include control information and data. To this end, the transceiver may include an RF transmitter for up-converting and amplifying a frequency of a transmitted signal, an RF receiver for low-noise amplifying and down-converting a frequency of a received signal, and the like. However, this is only an embodiment of the transceiver, and the elements of the transceiver are not limited to the RF transmitter and RF receiver.
In addition, the transceiver may receive a signal through a wireless channel and output the received signal to the UE processor 16-05, and may transmit a signal, which is output from the UE processor 16-05, through a wireless channel.
The memory (not shown) may store programs and data necessary for the operation of the UE. In addition, the memory may store control information or data included in a signal acquired by the UE. The memory may be configured as a storage medium, such as ROM, RAM, hard disk, CD-ROM, and DVD or a combination of storage media.
The UE processor 16-05 may control a series of processes so that the UE may operate according to the above-described embodiment. The UE processor 16-05 may be implemented as a controller or one or more processors.
With reference to
The base station receiver 17-00 and base station transmitter 17-10 may be collectively called a transceiver. According to the communication method of the base station described above, the base station receiver 17-00, base station transmitter 17-10, and base station processor 17-05 of the base station may operate. However, the elements of the base station are not limited to the above-described examples. For example, the base station may include more or fewer elements (e.g., a memory and the like) than the aforementioned elements. In addition, the base station receiver 17-00, base station transmitter 17-10, and base station processor 17-05 may be implemented in the form of a single chip.
The base station receiver 17-00 and base station transmitter 17-10 (or transceiver) may transmit or receive a signal to or from the UE. Here, the signal may include control information and data. To this end, the transceiver may include an RF transmitter for up-converting and amplifying a frequency of a transmitted signal, an RF receiver for low-noise amplifying and down-converting a frequency of a received signal, and the like. However, this is only an embodiment of the transceiver, and the elements of the transceiver are not limited to the RF transmitter and the RF receiver.
In addition, the transceiver may receive a signal through a wireless channel and output the received signal to the base station processor 17-05, and may transmit a signal, which is output from the base station processor 17-05, through a wireless channel.
The memory (not shown) may store programs and data necessary for the operation of the base station. In addition, the memory may store control information or data included in a signal acquired by the base station. The memory may be configured as a storage medium, such as ROM, RAM, hard disk, CD-ROM, and DVD or a combination of storage media.
The base station processor 17-05 may control a series of processes so that the base station may operate according to the above-described embodiment. The base station processor 17-05 may be implemented as a controller or one or more processors.
In addition, the NetRep of the disclosure may be the same or similar to the apparatus structure in
In the drawings in which methods of the disclosure are described, the order of the description does not always correspond to the order in which steps of each method are performed, and the order relationship between the steps may be changed or the steps may be performed in parallel.
Alternatively, in the drawings in which methods of the disclosure are described, some elements may be omitted and only some elements may be included therein without departing from the essential spirit and scope of the disclosure.
Further, in methods of the disclosure, some or all of the contents of each embodiment may be combined and performed without departing from the essential spirit and scope of the disclosure.
Further, although not set forth in the disclosure, methods which use separate tables or information including at least one element contained in the tables proposed in the disclosure are also possible.
Meanwhile, the embodiments of the disclosure disclosed in the specification and drawings are merely provided as specific examples to easily explain the technical content of the disclosure and aid understanding of the disclosure, and are not intended to limit the scope of the disclosure. In other words, it is obvious to those skilled in the art that other modifications based on the technical idea of the disclosure can be implemented. In addition, each of the above embodiments can be operated in combination with each other as needed.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2022-0029621 | Mar 2022 | KR | national |
| 10-2022-0072984 | Jun 2022 | KR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2023/003148 | 3/8/2023 | WO |
