KR20220015954A - Apparatus and method for transmitting ran slicing information - Google Patents

Abstract

The present specification relates to a device for transmitting RAN slicing related information and a method thereof. Disclosed is a terminal which comprises: a transceiving unit configured to receive individual control information provided individually for each RAN slice from a network node and to perform a random access procedure by using a resource individually configured for each RAN slice based on the individual control information; and a processor for controlling receiving of the individual control information and the random access procedure. The terminal provides an effect of separating and transmitting control information including, for example, system information for each slice for RAN slicing.

Description

Apparatus and method for transmitting RAN slicing related information {APPARATUS AND METHOD FOR TRANSMITTING RAN SLICING INFORMATION}

The present invention relates to a wireless communication system, and more particularly, to an apparatus and method for transmitting RAN slicing related information.

3GPP paved the way for commercial application of 5G by completing the first global 5G New Radio (NR) standard in Release (Rel)-15. 5G NR provides an improved data rate compared to LTE Evolved UMTS Terrestrial Radio Access (E-UTRA), and a radio access technology that can satisfy various QoS requirements required for each segmented and detailed usage scenario to be. In particular, enhancement Mobile BroadBand (eMBB), massive Machine-Type Communications (mMTC), and Ultra Reliable and Low Latency Communications (URLLC) have been defined as representative usage scenarios of 5G. As a method to satisfy the requirements for each scenario, flexible (numerology) compared to LTE is provided.

In addition, a network slicing technique is being considered. The network slicing technology provides network resources and network functions for each service by creating an end-to-end (E2E) resource spanning from a Radio Access Network (RAN) to a Core Network (CN) into one independent slice. 5G movement that can apply properties such as network isolation, customization, and independent management and orchestration to the RAN (Radio Access Network) and the core network of mobile communication It is a new concept applied to communication.

Communication technology combines with the development of technologies such as Network Function Virtualization (NFV) and Software Defined Network (SDN) to create a network slice optimized for the characteristics of each application in one huge network. developed in a way that constitutes

Network Slice creates a logically separated network with E2E (End-to-End) including radio access, transmission, and 5G core equipment from the terminal through one physical network to provide different characteristics and QoS (Quality of Service). It provides a dedicated network specialized for the various services it has. That is, the network slice is a technology that provides network resources and network functions necessary for the service requested by the terminal as one independent slice.

An object of the present invention is to provide an apparatus and method for transmitting RAN slicing related information. In order to efficiently support various services in 5G mobile communication, that is, to support multiple services with one system without having an individual system for each of the various services, it should be possible to dynamically control resources through slicing. . However, RAN slicing has a greater difficulty than slicing for the core network. In the RAN slicing concept, each slice can operate as an independent cell, and each slice is isolated and can be operated independently so that it does not affect other slices even in an operation failure state for one slice. is required to be Accordingly, there is a need for a method for separately transmitting information on each RAN slice.

A terminal operating in a communication system supporting radio access network (RAN) slice information according to an aspect of the present invention for achieving the above object receives, from a network node, individual control information provided individually for each RAN slice, a transceiver configured to perform a random access procedure using individually configured resources for each RAN slice based on the individual control information; and a processor controlling the reception of the individual control information and the random access procedure.

The individual control information is system information, and the system information includes at least one of first control information for a slice of a first type and second control information for a slice of a second type, and the processor is configured to control the first control information. and control the random access procedure in the slice of the first type based on the information, and control the random access procedure in the slice of the second type based on the second control information.

The first control information and the second control information include random access parameter information, random access resource information, initial bandwidth information, time duplex division (TDD) configuration information, slice resource information on frequency, slice resource information on time, CORESET 0, respectively. (Control Channel Resource Set 0), search space, basic SCS (SubCarrier Spacing) for each slice, BWP (BandWidth Part), service cell configuration SIBs (System Information Blocks), RACH (Random Access Channel) information may include at least one have.

The system information may further include an information value indicating whether the network node supports the RAN slice operation.

The first control information and the second control information may be configured such that components thereof are different from each other or that at least one of values of the components are different from each other.

The system information further includes identification information of each slice, wherein the processor extracts the first control information based on a first identification code corresponding to the slice of the first type, and adds the first control information to the slice of the second type. and extract the second control information based on a corresponding second identification code.

The system information includes reception control information for controlling reception of at least one of the first control information and the second control information, and the processor includes the first control information and the second control information based on the reception control information. It may be configured to control reception of at least one of the control information.

The reception control information may include first reception control information corresponding to the first type of slice and second reception control information corresponding to the second type of slice.

The reception control information includes information on the position of the first DM-RS (DeModulation Reference Signal) symbol in the frequency or spatial domain, SIB1 neurology information, information related to CORESET for SIB1 scheduling, search space information, PDCCH ( Physical Downlink Control Channel) related parameter information may be included.

The processor may use the second control information even if the first control information cannot be used even to control communication in the first type of slice or to control communication in the second type of slice If not, it may be configured to control communication based on basic control information and basic configuration resources.

A network node operating in a communication system supporting RAN (Radio Access Network) slice information according to an aspect of the present invention for achieving the above object, transmits individual control information provided individually for each RAN slice to the terminal, a transceiver configured to provide a random access procedure using individually configured resources for each RAN slice based on the individual control information; and a processor for controlling transmission and reception of the individual control information and the random access procedure.

The individual control information is system information, and the system information includes at least one of first control information for a slice of a first type and second control information for a slice of a second type, and the processor is configured to control the first control information. and control the random access procedure in the slice of the first type based on the information, and control the random access procedure in the slice of the second type based on the second control information.

The first control information and the second control information are, respectively, random access parameter information, random access resource information, initial bandwidth information, TDD configuration information, slice resource information on frequency, slice resource information on time, CORESET 0, search space, slice It may include at least one of basic SubCarrier Spacing (SCS), BandWidth Part (BWP), Service Cell Setting System Information Blocks (SIBs), and Random Access Channel (RACH) information.

The first control information and the second control information may be configured such that components thereof are different from each other or that at least one of values of the components are different from each other.

The system information further includes identification information of each slice, wherein the processor includes, based on a first identification code corresponding to the slice of the first type, first control information in the system information, and the second type It may be configured to include second control information in the system information based on a second identification code corresponding to a slice of .

The system information may include reception control information for controlling reception of at least one of the first control information and the second control information.

The reception control information may include first reception control information corresponding to the first type of slice and second reception control information corresponding to the second type of slice.

The reception control information includes at least one of information on the position of the first DM-RS symbol in the frequency or spatial domain, SIB1 neurology information, CORESET-related information for SIB1 scheduling, search space information, and PDCCH-related parameter information. may include

The processor generates a handover message to be transmitted to the terminal when the terminal needs to be handed over to another network node, and when the other network node supports RAN slice-based communication, the first type of At least one of the first handover information for the first slice and the second handover information for the second type of slice is included in the handover message, and the other network node does not support RAN slice-based communication. In this case, basic handover information for the other network node may be included in the handover message, and the transceiver may be configured to transmit the handover message to the terminal.

In a communication system supporting RAN (Radio Access Network) slice information according to an aspect of the present invention for achieving the above object, a method of performing communication by a terminal is a network method using individual control information provided individually for each RAN slice. receiving from a node; and performing a random access procedure using individually configured resources for each RAN slice based on the individual control information, wherein the individual control information is system information, and the system information includes first control information and second at least one of control information, wherein a random access procedure in a slice of a first type is controlled based on the first control information, and a random access procedure in a slice of a second type is controlled based on the second control information. It can be a controlled method.

According to the apparatus and method of the present invention, there is an effect that, for RAN slicing, control information including, for example, system information can be transmitted separately for each slice. According to one aspect, a unique ID is designated for each slice (eg, including eMBB, URLLC, V2X slice, etc.), and each slice ID may be configured to distinguish different services or slices. For example, when transmitting system information allocated for each slice, there is an effect that information can be transmitted based on the slice ID as described above.

1 is a conceptual diagram illustrating a wireless communication system according to an embodiment of the present invention.
2 is an exemplary diagram illustrating an NR system to which a data transmission method according to an embodiment of the present invention can be applied.
3 is a diagram for explaining a resource grid supported by a radio access technology to which this embodiment can be applied.
4 is a diagram for explaining a bandwidth part (BWP) supported by a radio access technology to which the present embodiment can be applied.
5 is a diagram exemplarily illustrating a Sync. Signal Block (SSB) in a radio access technology to which the present embodiment can be applied.
6 is a diagram for explaining a random access procedure in a radio access technology to which this embodiment can be applied.
7 is a diagram for explaining a concept of a network slice according to an embodiment.
8 shows a terminal and a network node in which an embodiment of the present invention is implemented.

Since the present invention can have various changes and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, and it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention. In describing each figure, like reference numerals have been used for like elements.

In this specification, terms such as “first”, “second”, “A”, and “B” may be used to describe various components, but the components should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. The term “and/or” also includes combinations of a plurality of related listed items or any of a plurality of related listed items.

When an element is referred to as being “connected” or “connected” to another element, it is understood that it may be directly connected or connected to the other element, but other elements may exist in between. it should be On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle.

The terminology used herein is used only to describe specific embodiments, and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In this specification, terms such as "comprise" or "have" are intended to designate that a feature, number, step, operation, component, part, or a combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, terms used herein have the same meanings as commonly understood by those of ordinary skill in the art to which the present invention belongs, including technical or scientific terms. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present specification. does not

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a conceptual diagram illustrating a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 1 , a wireless communication system 100 includes a plurality of communication nodes 110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3. , 130-4, 130-5, 130-6).

Each of the plurality of communication nodes may support at least one communication protocol. For example, each of the plurality of communication nodes is a CDMA (Code Division Multiple Access) based communication protocol, WCDMA (Wideband CDMA) based communication protocol, TDMA (Time Division Multiple Access) based communication protocol, FDMA (Frequency Division Multiple) Access) based communication protocol, OFDM (Orthogonal Frequency Division Multiplexing) based communication protocol, OFDMA (Orthogonal Frequency Division Multiple Access) based communication protocol, SC (Single Carrier)-FDMA based communication protocol, NOMA (Non-Orthogonal Multiplexing) Access)-based communication protocol, space division multiple access (SDMA)-based communication protocol, etc. may be supported.

The wireless communication system 100 includes a plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 and a plurality of user equipments 130-1, 130-2, 130-3, 130-4, 130-5, 130-6).

Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may form a macro cell. Each of the fourth base station 120-1 and the fifth base station 120-2 may form a small cell. The fourth base station 120-1, the third terminal 130-3, and the fourth terminal 130-4 may belong to the coverage of the first base station 110-1. The second terminal 130-2, the fourth terminal 130-4, and the fifth terminal 130-5 may belong to the coverage of the second base station 110-2. The fifth base station 120-2, the fourth terminal 130-4, the fifth terminal 130-5, and the sixth terminal 130-6 may belong to the coverage of the third base station 110-3. . The first terminal 130-1 may belong to the coverage of the fourth base station 120-1. The sixth terminal 130-6 may belong to the coverage of the fifth base station 120-2.

Here, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 is a NodeB, an evolved NodeB, and a next generation Node B (NodeB). B, gNB), BTS (Base Transceiver Station), radio base station (radio base station), radio transceiver (radio transceiver), access point (access point), access node (node), roadside unit (road side unit, RSU), DU (Digital Unit), CDU (Cloud Digital Unit), RRH (Radio Remote Head), RU (Radio Unit), TP (Transmission Point), TRP (transmission and reception point), to be referred to as a relay node (relay node), etc. can Each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, 130-6 is a terminal, an access terminal, a mobile terminal, It may be referred to as a station, a subscriber station, a mobile station, a portable subscriber station, a node, a device, and the like.

A plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6) Each can support cellular (cellular) communication (eg, long term evolution (LTE), LTE-A (advanced), NR (New Radio), etc. defined in the 3rd generation partnership project (3GPP) standard). Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may operate in different frequency bands or may operate in the same frequency band. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to each other through an ideal backhaul or a non-ideal backhaul, and the ideal backhaul Alternatively, information may be exchanged with each other through a non-ideal backhaul. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to a core network (not shown) through an ideal backhaul or a non-ideal backhaul. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits a signal received from the core network to the corresponding terminals 130-1, 130-2, 130-3, 130 -4, 130-5, 130-6), and a signal received from the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) is transmitted to the core network can be sent to

Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may support OFDM-based downlink transmission. In addition, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may support OFDM or DFT-Spread-OFDM-based uplink transmission. In addition, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits multiple input multiple output (MIMO) (eg, single user (SU)-MIMO, MU (Multi User)-MIMO, massive MIMO, etc.), Coordinated Multipoint (CoMP) transmission, carrier aggregation transmission, transmission in an unlicensed band, direct device to device, D2D) communication (or Proximity services (ProSe)) may be supported, etc. Here, each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, 130-6 Base stations 110-1, 110-2, 110-3, 120-1, 120-2 and corresponding operations and/or base stations 110-1, 110-2, 110-3, 120-1, 120-2 ) can perform operations supported by

For example, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 based on the SU-MIMO method, and the fourth terminal 130-4 may transmit a signal based on the SU-MIMO method. A signal may be received from the second base station 110 - 2 . Alternatively, the second base station 110 - 2 may transmit a signal to the fourth terminal 130 - 4 and the fifth terminal 130 - 5 based on the MU-MIMO scheme, and the fourth terminal 130 - 4 . and each of the fifth terminals 130 - 5 may receive a signal from the second base station 110 - 2 by the MU-MIMO method. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may transmit a signal to the fourth terminal 130-4 based on the CoMP scheme, and the fourth The terminal 130-4 may receive signals from the first base station 110-1, the second base station 110-2, and the third base station 110-3 by the CoMP method. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 includes the terminals 130-1, 130-2, 130-3, 130-4, 130-5, 130-6) and a signal may be transmitted/received based on the CA method.

Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 coordinates D2D communication between the fourth terminal 130-4 and the fifth terminal 130-5. (coordination), each of the fourth terminal 130-4 and the fifth terminal 130-5 is D2D communication by the coordination of each of the second base station 110-2 and the third base station 110-3 can be performed.

Hereinafter, even when a method (eg, transmission or reception of a signal) performed in a first communication node among communication nodes is described, a second communication node corresponding thereto corresponds to the method performed in the first communication node A method (eg, receiving or transmitting a signal) may be performed. That is, when the operation of the terminal is described, the corresponding base station may perform the operation corresponding to the operation of the terminal. Conversely, when the operation of the base station is described, the corresponding terminal may perform the operation corresponding to the operation of the base station.

Also, hereinafter, downlink (DL) means communication from a base station to a terminal, and uplink (UL) means communication from a terminal to a base station. In the downlink, the transmitter may be a part of the base station, and the receiver may be a part of the terminal. In the uplink, the transmitter may be a part of the terminal, and the receiver may be a part of the base station.

Recently, as the spread of smartphones and Internet of Things (IoT) terminals is rapidly spreading, the amount of information exchanged through a communication network is increasing. Accordingly, in the next-generation wireless access technology, an environment (eg, enhanced mobile broadband communication) that provides a faster service to more users than the existing communication system (or the existing radio access technology) )) needs to be considered. To this end, design of a communication system in consideration of MTC (Machine Type Communication) providing a service by connecting a plurality of devices and objects is being discussed. In addition, the design of a communication system (eg, URLLC (Ultra-Reliable and Low Latency Communication) that considers a service and/or terminal sensitive to communication reliability and/or latency) is being discussed

Hereinafter, in this specification, for convenience of description, the next-generation radio access technology is referred to as a New Radio Access Technology (RAT), and a wireless communication system to which the New RAT is applied is referred to as a New Radio (NR) system. In the present specification, NR-related frequencies, frames, subframes, resources, resource blocks, regions, bands, subbands, control channels, data channels, synchronization signals, various reference signals, various signals, or various messages are past or present. It can be interpreted in various meanings used or used in the future.

2 is an exemplary diagram illustrating an NR system to which a data transmission method according to an embodiment of the present invention can be applied.

NR, a next-generation wireless communication technology that is being standardized in 3GPP, provides an improved data rate compared to LTE and is a radio access technology that can satisfy various QoS requirements required for each segmented and detailed usage scenario. . In particular, eMBB (enhanced Mobile BroadBand), mMTC (massive MTC), and URLLC (Ultra Reliable and Low Latency Communications) have been defined as representative usage scenarios of NR. As a method for satisfying the requirements for each scenario, a frame structure that is flexible compared to LTE is provided. The frame structure of NR supports a frame structure based on multiple subcarriers. The basic subcarrier spacing (SubCarrier Spacing, SCS) becomes 15 kHz, and 15 kHz*2^n (n=0, 1, 2, 3, 4) supports a total of 5 types of SCS.

Referring to Figure 2, the NG-RAN (Next Generation-Radio Access Network) is a control plane (RRC) protocol termination for the NG-RAN user plane (SDAP / PDCP / RLC / MAC / PHY) and UE (User Equipment) It is composed of gNBs that provide Here, NG-C represents a control plane interface used for the NG2 reference point between the NG-RAN and the 5GC (5 Generation Core). NG-U represents the user plane interface used for the NG3 reference point between NG-RAN and 5GC.

The gNBs are interconnected through the Xn interface and connected to the 5GC through the NG interface. More specifically, the gNB is connected to an Access and Mobility Management Function (AMF) through the NG-C interface and to a User Plane Function (UPF) through the NG-U interface.

In the NR system of FIG. 2, multiple numerologies may be supported. Here, the numerology may be defined by a subcarrier spacing and a cyclic prefix (CP) overhead. In this case, the plurality of subcarrier intervals may be derived by scaling the basic subcarrier interval by an integer. Also, although it is assumed that very low subcarrier spacing is not used at very high carrier frequencies, the numerology used can be selected independently of the frequency band.

In addition, in the NR system, various frame structures according to a number of numerologies may be supported.

<NR Waveform, Pneumologic and Frame Structure>

In NR, a CP-OFDM waveform using a cyclic prefix is used for downlink transmission, and CP-OFDM or DFT-S-OFDM is used for uplink transmission. OFDM technology is easy to combine with MIMO (Multiple Input Multiple Output), and has advantages of using a low-complexity receiver with high frequency efficiency.

Meanwhile, in NR, since the requirements for data rate, delay rate, coverage, etc. are different for each of the three scenarios described above, it is necessary to efficiently satisfy the requirements for each scenario through the frequency band constituting an arbitrary NR system. . To this end, a technique for efficiently multiplexing a plurality of different numerology-based radio resources has been proposed.

Specifically, the NR transmission numerology is determined based on sub-carrier spacing and cyclic prefix (CP), and the μ value is used as an exponential value of 2 based on 15 kHz as shown in Table 1 below. is changed to

μ subcarrier spacing
(kHz) Cyclic prefix Supported for data Supported for synch 0 15 Normal Yes Yes One 30 Normal Yes Yes 2 60 Normal, Extended Yes No 3 120 Normal Yes Yes 4 240 Normal No Yes

As shown in Table 1 above, the NR numerology can be divided into five types according to the subcarrier spacing. This is different from the fact that the subcarrier interval of LTE, one of the 4G communication technologies, is fixed at 15 kHz. Specifically, in NR, subcarrier intervals used for data transmission are 15, 30, 60, and 120 kHz, and subcarrier intervals used for synchronization signal transmission are 15, 30, 120, 240 kHz. In addition, the extended CP is applied only to the 60 kHz subcarrier interval. On the other hand, as for the frame structure in NR, a frame having a length of 10 ms is defined, which is composed of 10 subframes having the same length of 1 ms. One frame can be divided into half frames of 5 ms, and each half frame includes 5 subframes. In the case of a 15 kHz subcarrier interval, one subframe consists of one slot, and each slot consists of 14 OFDM symbols.

<NR Physical Resources>

In relation to a physical resource in NR, an antenna port, a resource grid, a resource element, a resource block, a bandwidth part, etc. are considered do.

An antenna port is defined such that a channel on which a symbol on an antenna port is carried can be inferred from a channel on which another symbol on the same antenna port is carried. When the large-scale property of a channel on which a symbol on one antenna port is carried can be inferred from a channel on which a symbol on another antenna port is carried, the two antenna ports are QC/QCL (quasi co-located or It can be said that there is a quasi co-location) relationship. Here, the wide range characteristic includes at least one of a delay spread, a Doppler spread, a Doppler shift, an average delay, and a spatial Rx parameter.

3 is a diagram for explaining a resource grid supported by a radio access technology to which this embodiment can be applied.

Referring to FIG. 3 , in the resource grid, since NR supports a plurality of numerologies on the same carrier, a resource grid may exist according to each numerology. In addition, the resource grid may exist according to an antenna port, a subcarrier interval, and a transmission direction.

A resource block consists of 12 subcarriers, and is defined only in the frequency domain. In addition, a resource element is composed of one OFDM symbol and one subcarrier. Accordingly, as in FIG. 3 , the size of one resource block may vary according to the subcarrier interval. In addition, NR defines "Point A" serving as a common reference point for a resource block grid, a common resource block, a physical resource block, and the like.

4 is a diagram for explaining a bandwidth part supported by a radio access technology to which the present embodiment can be applied.

In NR, unlike LTE in which the carrier bandwidth is fixed at 20 MHz, the maximum carrier bandwidth is set from 50 MHz to 400 MHz for each subcarrier interval. Therefore, it is not assumed that all terminals use all of these carrier bandwidths. Accordingly, in NR, as shown in FIG. 4, a bandwidth part (BWP) may be designated within the carrier bandwidth and used by the terminal. In addition, the bandwidth part is associated with one neurology and is composed of a subset of continuous common resource blocks, and may be dynamically activated according to time. Up to four bandwidth parts are configured in the terminal, respectively, in uplink and downlink, and data is transmitted/received using the activated bandwidth part at a given time.

In the case of a paired spectrum, the uplink and downlink bandwidth parts are set independently, and in the case of an unpaired spectrum, to prevent unnecessary frequency re-tunning between downlink and uplink operations For this purpose, the downlink and uplink bandwidth parts are set in pairs to share a center frequency.

<NR Initial Connection>

In NR, the terminal accesses the base station and performs a cell search and random access procedure in order to perform communication.

Cell search is a procedure in which the terminal synchronizes with the cell of the corresponding base station using a synchronization signal block (SSB) transmitted by the base station, obtains a physical layer cell ID, and obtains system information.

5 is a diagram exemplarily illustrating a synchronization signal block in a radio access technology to which the present embodiment can be applied.

Referring to FIG. 5, the SSB consists of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS) occupying 1 symbol and 127 subcarriers, respectively, and a PBCH spanning 3 OFDM symbols and 240 subcarriers. .

The UE receives the SSB by monitoring the SSB in the time and frequency domains.

SSB can be transmitted up to 64 times in 5ms. A plurality of SSBs are transmitted using different transmission beams within 5 ms, and the UE performs detection on the assumption that SSBs are transmitted every 20 ms when viewed based on one specific beam used for transmission. The number of beams that can be used for SSB transmission within 5 ms time may increase as the frequency band increases. For example, up to 4 SSB beams can be transmitted in 3 GHz or less, and SSB can be transmitted using up to 8 different beams in a frequency band of 3 to 6 GHz and up to 64 different beams in a frequency band of 6 GHz or more.

Two SSBs are included in one slot, and the start symbol and the number of repetitions within the slot are determined according to the subcarrier interval as follows.

On the other hand, the SSB is not transmitted at the center frequency of the carrier bandwidth, unlike the SS of the conventional LTE. That is, the SSB may be transmitted in a place other than the center of the system band, and a plurality of SSBs may be transmitted in the frequency domain when wideband operation is supported. Accordingly, the UE monitors the SSB using a synchronization raster that is a candidate frequency location for monitoring the SSB. The carrier raster and synchronization raster, which are the center frequency location information of the channel for initial access, are newly defined in NR. Compared to the carrier raster, the synchronization raster has a wider frequency interval than that of the carrier raster. can

The UE may acquire the MIB through the PBCH of the SSB. MIB (Master Information Block) includes minimum information for the terminal to receive the remaining system information (RMSI, Remaining Minimum System Information) broadcast by the network. In addition, the PBCH includes information on the position of the first DM-RS symbol in the time domain, information for the UE to monitor SIB1 (eg, SIB1 neurology information, information related to SIB1 CORESET, search space information, PDCCH related parameter information, etc.), offset information between the common resource block and the SSB (the position of the absolute SSB in the carrier is transmitted through SIB1), and the like. Here, the SIB1 neurology information is equally applied to some messages used in the random access procedure for accessing the base station after the UE completes the cell search procedure. For example, the neurology information of SIB1 may be applied to at least one of messages 1 to 4 for the random access procedure.

The aforementioned RMSI may mean System Information Block 1 (SIB1), and SIB1 is periodically broadcast (eg, 160 ms) in the cell. SIB1 includes information necessary for the UE to perform an initial random access procedure, and is periodically transmitted through the PDSCH. In order for the UE to receive SIB1, it must receive neurology information used for SIB1 transmission and CORESET (Control Resource Set) information used for scheduling SIB1 through the PBCH. The UE checks scheduling information for SIB1 by using SI-RNTI in CORESET, and acquires SIB1 on PDSCH according to the scheduling information. SIBs other than SIB1 may be transmitted periodically or may be transmitted according to the request of the terminal.

6 is a diagram for explaining a random access procedure in a radio access technology to which this embodiment can be applied.

Referring to FIG. 6 , upon completion of cell search, the terminal transmits a random access preamble for random access to the base station. The random access preamble is transmitted through the PRACH. Specifically, the random access preamble is transmitted to the base station through a PRACH consisting of continuous radio resources in a specific slot that is periodically repeated. In general, when a UE initially accesses a cell, a contention-based random access procedure is performed, and when random access is performed for beam failure recovery (BFR), a contention-free random access procedure is performed.

The terminal receives a random access response to the transmitted random access preamble. The random access response may include a random access preamble identifier (ID), a UL grant (uplink radio resource), a Temporary Cell - Radio Network Temporary Identifier (TC-RNTI), and a Time Advance Command (TAC). Since one random access response may include random access response information for one or more UEs, the random access preamble identifier may be included to inform which UE the included UL Grant, TC-RNTI, and TAC are valid. The random access preamble identifier may be an identifier for the random access preamble received by the base station. The TAC may be included as information for the UE to adjust uplink synchronization. The random access response may be indicated by a random access identifier on the PDCCH, that is, RA-RNTI (Random Access - Radio Network Temporary Identifier).

Upon receiving the valid random access response, the terminal processes information included in the random access response and performs scheduled transmission to the base station. For example, the UE applies the TAC and stores the TC-RNTI. In addition, data stored in the buffer of the terminal or newly generated data is transmitted to the base station by using the UL grant. In this case, information for identifying the terminal should be included.

Network Slicing

Network slicing is an independent slice of E2E (End-to-End) resources spanning from a Radio Access Network (RAN) to a Core Network (CN) for each service by network resources and network functions. By creating and providing the It is a new concept applied to 5G mobile communication.

Communication technology combines with the development of technologies such as Network Function Virtualization (NFV) and Software Defined Network (SDN) to create a network slice that is optimized for application characteristics for each application in one huge network. ) is developed in a way that constitutes

Network slice creates a logically separated E2E (End-to-End) network, including radio access, transmission, and 5G core equipment, from a terminal through one network physically, and provides various services with different characteristics. It provides a dedicated network specialized for services. That is, the network slice is a technology that provides network resources and network functions necessary for the service requested by the terminal as one independent slice.

7 is a diagram for explaining a concept of a network slice according to an embodiment.

Referring to FIG. 7 , one network slice consists of an E2E logical network including a counterpart node (a counterpart terminal or a counterpart application server) from a terminal. A user can receive a service by accessing a network slice specialized for the application (eMBB, URLLC, MIoT, V2X, etc.) used. That is, the user's terminal may simultaneously access one or more network slices. Each slice may be identified by a slice/service type (SST) mapped to an expected network operation in terms of services and characteristics.

A mobile communication operator may allocate network resources suitable for a corresponding service for each slice or for each set of a specific slice. The network resource may refer to a logical resource or radio resource allocation provided by a network function (NF) or a network function (NF). A network slice instance (NSI) may be defined as a set of network function instances and required resources forming a deployed network slice.

In describing the embodiments of the present disclosure, a slice, a service, a network slice, a network service, an application slice, an application service, etc. may be mixed and used.

Random Access Procedure in Network Slicing

In order to switch from IDLE (RRC_IDLE) state to ACTIVE (RRC_CONNECTED) state in NR, the UE transmits a random access preamble for a corresponding RACH occasion (RACH occasion: RO) to a network node, and the network node receives the random access preamble and then TA (Timing advance) It can be used for setting synchronization with the terminal through estimation. The UE transmits the random access preamble at different times according to the difference in delay time with the network node, and the network node detects a plurality of random access preambles, respectively, in various random access preamble formats and random access preamble monitoring period according to various scenarios. This is set

When network slicing is applied, a mobile communication operator may allocate a network resource suitable for a corresponding service for each slice or a specific set of slices, and the terminal may access one or more slices. To this end, the UE may perform a random access procedure for each independent slice. RAN slices constituting end-to-end (E2E) network slicing may be provided separately through division of frequency bands (eg, 3.5 GHz, 28 GHz) and/or time, and are allocated for a random access procedure for each slice Frequency and time resources, or preamble structures may also be different. Here, a method for transmitting information on each slice separately is required.

Transmitting individual control information for RAN slicing

Along with the net neutrality issue, the importance of network slicing technology is growing.

In order to efficiently support various services in 5G mobile communication, that is, to support multiple services with one system without having an individual system for each of the various services, it should be possible to dynamically control resources through slicing. . However, RAN slicing has a greater difficulty than slicing for the core network. In the RAN slicing concept, each slice can operate as an independent cell, and each slice is isolated and can be operated independently so that it does not affect other slices even in an operation failure state for one slice. is required to be

For this, it is important to properly slice the resources managed by one base station from the upper layer to the physical layer. The upper layer can be implemented for each function and thus can be solved relatively easily in software, but it can be more difficult to separate (slicing) in software as it goes to the lower layer. For example, it may be required to implement a modem for communication using Software Defined Radio (SDR). Thus, a step-by-step approach may be considered. Such an embodiment may include a method of implementing the upper layer as Network Function Virtualization (NFV) and implementing the lower layer to perform independent scheduling for each service or slice.

Under such a situation, a method for separating and transmitting control information including, for example, system information for each slice for RAN slicing is required.

In a communication system to which network slicing is not applied, the network node is required to transmit to the terminal within system information (eg, MIB (Master Information Block), SIB1 (System Information Block1) message) without considering the slice configuration (configuration) Information (eg, random access parameter and/or resource information, initial bandwidth part (BWP) information, etc.) may be transmitted. However, in order to implement RAN slicing, since characteristics required for each type of service or slice are different, the configuration information or system information must be transmitted separately for each slice. For example, information about whether the Initial Bandwidth Part (Initial BWP) should be set to a specific BWP for a specific slice or service, or random access parameters and/or resource information, or how the TDD setting is configured for a specific slice or service Information on whether or not to be performed may be transmitted from the network node to the terminal.

When the RAN slicing-related information is transmitted from the network node to the terminal, the RAN slicing-related information is, for example, from the network node in the form of at least one of system information, an RRC message, MAC CE (Control Element), and DCI (Downlink Control Information). may be transmitted to the terminal.

According to one aspect, a unique ID is designated for each slice (eg, including eMBB, URLLC, V2X slice, etc.), and each slice ID may be configured to distinguish different services or slices. For example, when transmitting system information allocated for each slice, information may be transmitted based on the slice ID as described above.

Meanwhile, information on the RAN slice may be used for handover between slices. Here, the inter-slice handover is a handover between a plurality of slices provided by the same base station (or cell), a handover between slices provided by different base stations (or cells), and a RAN slice from a base station (or cell) providing a slice. It may include handover to a base station (or cell) not providing a RAN slice or handover from a base station (or cell) not providing a RAN slice to a specific slice of a base station (or cell) providing a RAN slice. . For handover between slices, parameters may be predetermined for each slide, and the network node and the terminal may be aware of the parameters at the time of handover through transmission of slice-related information from the network node to the terminal.

Meanwhile, information related to each slice may be transmitted from the network node to the terminal step by step through a plurality of message types. For example, ID information for each slice in consideration of each service type (eg, eMBB, URLLC, V2X, etc.) may be included in MIB or SIB1, and based on the slice ID assigned to each slice, each terminal requests It may be configured to additionally receive only information on one or more slices to be used.

Meanwhile, according to one aspect, the network node transmits information on slices available in the corresponding network node to the terminal based on, for example, system information, and the terminal in which a desired service or slice exists among the available slices uses the corresponding use A terminal that uses available slices, and a desired service or slice does not exist or does not support RAN slicing may be configured to use a default slice.

Send system information

The network node may transmit at least a portion of the system information differently for each slice to support RAN slicing. The system information may include, for example, MIB or SIB.

According to one aspect, the MIB may be equally transmitted for different slices, and a different SIB1 (or RMSI) may be transmitted for each slice. For example, the MIB may include RAN slicing operation information. The RAN slicing operation information may include information on whether the network node transmitting the MIB supports RAN slicing, and may consist of, for example, 1 to 2 bits. Meanwhile, the MIB may include resource information for obtaining SIB1 for each slice. For example, the MIB may include first resource information for the first slice and second resource information for the second slice. Upon receiving the MIB, the terminal responds to a determination that it wants to use the service corresponding to the first slice based on at least one of the first resource information and the second resource information, through the first resource information for the first slice. SIB1 can be received. Alternatively, the UE receiving the MIB may receive SIB1 for the second slice through the second resource information in response to a determination that it wants to use the service corresponding to the second slice.

According to another aspect, MIB and SIB1 may be configured to be transmitted in common for different slices. According to one aspect, the MIB may include information on whether RAN slicing is supported, and may be configured to receive different information for each slice in SIB1. For example, each of one or more configuration information or parameters included in SIB1 may be configured to have a value for each of a plurality of slices.

According to one aspect, different settings may be defined for each slice, and when SIB1 (RMSI) is assigned to each slice, each SIB1 may differently include configuration information for each corresponding slice, or Different information for a plurality of slices may be all included in, for example, common SIB1 (RMSI). Here, the information different for each slice may include, for example, at least one or more of the following information.

- Information on slice resources mainly on frequency/time.

- Initial BWP, CORESET 0, Search Space

- Basic SCS for each slice

- ServingCellConfigCommonSIB

- RACH related information

That is, for example, as setting information for each slice (eg, eMBB, URLLC, V2X, etc.), slice resource information on frequency and time, initial BWP for each slice, CORESET 0, Search Space, basic SCS (subcarrier for each slice) spacing, for example, set to 60 kHz in the case of URLLC), ServingCellConfigCommonSIB (defined in an RRC message), and RACH-related information (eg, in the case of URLLC slice, the RO period can be set to be relatively short) may be included.

The basic concept of RAN slicing may be to virtually divide and operate to support a variety of various services based on one physical network node system. Configuration information for slicing network nodes and cores must be separately configured, and through this, UEs can have a form in which they can see only the zone or slice to which they belong.

Use of slice information in the handover process

At least one or more network nodes may or may not support RAN slicing. Accordingly, different types of handover procedures may be performed depending on whether RAN slicing is supported.

First, there may be a handover procedure between cells using RAN slicing. In this case, information on the RAN slice may be included in the handover message. In addition, information related to the RAN slice may be added where necessary among commands exchanged between cells in handover. Since the information on the RAN slice is included in the handover message, a predetermined terminal may be configured to continuously use the slice for the service used. For example, the terminal that used the eMBB slice in the first network node may be configured to use the eMBB slice even after handover to the second network node is performed.

Meanwhile, handover may be performed from a cell using RAN slicing to a cell not used. In this case, information on the RAN slice may be included in the handover message. For example, with respect to a parameter that used separate information about the RAN slice in the previous cell, a kind of default parameter matching the corresponding parameter may be defined and used.

Meanwhile, Handover may be performed from a cell not using RAN slicing to a cell used. In this case, it may be configured to receive information on the RAN slice to be used in the new cell and to inform parameters for using an appropriate slice according to the used application and QoS during handover. Alternatively, it may be configured so that an appropriate slice can be used by receiving necessary system information when handed over to a new cell.

For handover between cells that do not use RAN slicing, a conventional handover procedure may be borrowed.

Control methods for RAN slicing

According to one aspect, control for RAN slicing is performed through system information, RRC message, MAC CE, or DCI, and may be performed, for example, as follows. First, you can set the basics as System Information. In addition, if necessary, it can be set as an RRC message, and can be set to enable/disable activation/deactivation through MAC CE (Control Element). On the other hand, very dynamically changed content can be operated by including it in DCI (Downlink Control Information).

8 shows a terminal and a network node in which an embodiment of the present invention is implemented.

Referring to FIG. 8 , the terminal 1100 includes a processor 1110 , a memory 1120 , and a transceiver 1130 . The processor 1110 may be configured to implement the functions, processes, and/or methods described herein. The layers of the air interface protocol may be implemented in the processor 1110 .

The memory 1120 is connected to the processor 1110 and stores various information for driving the processor 1110 . The transceiver 1130 is connected to the processor 1110 to transmit a radio signal to the network node 1200 or receive a radio signal from the network node 1200 .

The network node 1200 includes a processor 1210 , a memory 1220 , and a transceiver 1230 . In this embodiment, the network node 1200 is a node of a non-terrestrial network, and may include an artificial satellite that performs a radio access procedure according to the present specification. Alternatively, in the present embodiment, the network node 1200 is a node of a terrestrial network, and may include a base station that performs a radio access procedure according to the present specification.

The processor 1210 may be configured to implement the functions, processes, and/or methods described herein. The layers of the air interface protocol may be implemented in the processor 1210 . The memory 1220 is connected to the processor 1210 and stores various information for driving the processor 1210 . The transceiver 1230 is connected to the processor 1210 to transmit a radio signal to the terminal 1100 or receive a radio signal from the terminal 1100 .

The processors 1110 and 1210 may include an application-specific integrated circuit (ASIC), other chipsets, logic circuits, and/or data processing devices. The memories 1120 and 1220 may include read-only memory (ROM), random access memory (RAM), flash memory, memory cards, storage media, and/or other storage devices. The transceivers 1130 and 1230 may include a baseband circuit for processing a radio frequency signal. When the embodiment is implemented in software, the above-described technique may be implemented as a module (process, function, etc.) that performs the above-described function. The modules may be stored in the memories 1120 and 1220 and executed by the processors 1110 and 1210 . The memories 1120 and 1220 may be inside or outside the processors 1110 and 1210 , and may be connected to the processors 1110 and 1210 through various well-known means.

In the exemplary system described above, methods that can be implemented according to the features of the present invention described above have been described on the basis of a flowchart. For convenience, the methods have been described as a series of steps or blocks, but the claimed features of the invention are not limited to the order of steps or blocks, and some steps may occur in a different order or concurrently with other steps as described above. In addition, those skilled in the art will understand that the steps shown in the flowchart are not exhaustive and that other steps may be included or that one or more steps of the flowchart may be deleted without affecting the scope of the present invention.

Claims (20)

In a terminal operating in a communication system supporting RAN (Radio Access Network) slice information,
a transceiver configured to receive individual control information provided individually for each RAN slice from a network node, and to perform a random access procedure using resources individually configured for each RAN slice based on the individual control information; and
A terminal comprising a processor for controlling the reception of the individual control information and the random access procedure.
The method of claim 1,
The individual control information is system information,
The system information includes at least one of first control information for a slice of a first type and second control information for a slice of a second type;
the processor is configured to control a random access procedure in the slice of the first type based on the first control information, and control a random access procedure in the slice of the second type based on the second control information; terminal.
3. The method of claim 2,
The first control information and the second control information include random access parameter information, random access resource information, initial bandwidth information, time duplex division (TDD) configuration information, slice resource information on frequency, slice resource information on time, CORESET 0, respectively. (Control Channel Resource Set 0), search space, basic SCS (SubCarrier Spacing) for each slice, BWP (BandWidth Part), service cell configuration SIBs (System Information Blocks), including at least one of RACH (Random Access Channel) information, terminal.
3. The method of claim 2,
The system information is
The terminal further includes an information value indicating whether the network node supports the RAN slice operation.
3. The method of claim 2,
The first control information and the second control information,
The components are different from each other, or at least one of the values of the components is configured to be different from each other, the terminal.
3. The method of claim 2,
The system information further includes identification information of each slice,
The processor extracts the first control information based on a first identification code corresponding to the slice of the first type, and the second control information based on a second identification code corresponding to the slice of the second type configured to extract
3. The method of claim 2,
The system information includes reception control information for controlling reception of at least one of the first control information and the second control information,
The processor is configured to control reception of at least one of the first control information and the second control information based on the reception control information.
8. The method of claim 7,
The reception control information comprises first reception control information corresponding to the slice of the first type and second reception control information corresponding to the slice of the second type, the terminal.
8. The method of claim 7,
The reception control information is
Information on the position of the first DeModulation Reference Signal (DM-RS) symbol in the frequency or spatial domain, SIB1 neurology information, information related to CORESET for SIB1 scheduling, search space information, and Physical Downlink Control Channel (PDCCH) related A terminal comprising at least one of parameter information.
3. The method of claim 2,
The processor is
When the first control information cannot be used to control communication in the first type of slice, or when the second control information cannot be used to control communication in the second type of slice, the default A terminal, configured to control communication based on the control information and the basic configuration resource.
In a network node operating in a communication system supporting RAN (Radio Access Network) slice information,
a transceiver configured to transmit individual control information provided individually for each RAN slice to the terminal, and to provide a random access procedure using resources individually configured for each RAN slice based on the individual control information; and
A network node comprising a processor for controlling transmission and reception of the individual control information and the random access procedure.
12. The method of claim 11,
The individual control information is system information,
The system information includes at least one of first control information for a slice of a first type and second control information for a slice of a second type;
the processor is configured to control a random access procedure in the slice of the first type based on the first control information, and control a random access procedure in the slice of the second type based on the second control information; network node.
13. The method of claim 12,
The first control information and the second control information are, respectively, random access parameter information, random access resource information, initial bandwidth information, TDD configuration information, slice resource information on frequency, slice resource information on time, CORESET 0, search space, slice A network node comprising at least one of basic SubCarrier Spacing (SCS), BandWidth Part (BWP), Service Cell Configuration System Information Blocks (SIBs), and Random Access Channel (RACH) information.
13. The method of claim 12,
The first control information and the second control information,
A network node, configured such that its components are different from each other, or that at least one of the values of the components is different from each other.
13. The method of claim 12,
The system information further includes identification information of each slice,
The processor is
First control information is included in the system information based on a first identification code corresponding to the first type of slice, and second control information is included in the system information based on a second identification code corresponding to the second type of slice. A network node, configured for inclusion in system information.
13. The method of claim 12,
The system information includes reception control information for controlling reception of at least one of the first control information and the second control information.
17. The method of claim 16,
The reception control information includes first reception control information corresponding to the slice of the first type and second reception control information corresponding to the slice of the second type, the network node.
17. The method of claim 16,
The reception control information is
Information on the position of the first DM-RS symbol in the frequency or spatial domain, SIB1 neurology information, CORESET-related information for SIB1 scheduling, search space information, and PDCCH-related parameter information comprising at least one of the terminal.
3. The method of claim 2,
The processor is
When the terminal needs to be handed over to another network node, a handover message to be transmitted to the terminal is generated;
When the other network node supports RAN slice-based communication, at least one of first handover information for the first slice of the first type and second handover information for the second type of slice is transmitted to the handover. included in the message,
When the other network node does not support RAN slice-based communication, basic handover information for the other network node is included in the handover message,
The transceiver unit,
and send the handover message to the terminal.
In a communication system supporting RAN (Radio Access Network) slice information, a method of performing communication by a terminal, the method comprising:
Receiving individual control information provided individually for each RAN slice from a network node; and
performing a random access procedure using individually configured resources for each RAN slice based on the individual control information;
The individual control information is system information, the system information includes at least one of first control information and second control information, and a random access procedure in a slice of a first type is controlled based on the first control information, , a method in which a random access procedure in a second type of slice is controlled based on the second control information.

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