KR102408713B1 - Method, apparatus and system for distinguishing a terminal in a power saving mode and transmitting a paging signal for waking a terminal operating in a power saving mode - Google Patents

Abstract

The present disclosure relates to a communication technique that converges a 5G communication system for supporting a higher data rate after a 4G system with IoT technology, and a system thereof. The present disclosure provides intelligent services (eg, smart home, smart building, smart city, smart car or connected car, healthcare, digital education, retail business, security and safety related services, etc.) based on 5G communication technology and IoT-related technology. ) can be applied to
The present invention is a power saving mode operation procedure of a terminal for a system including one or more base stations and one or more terminals, and a method of classifying terminals of a base station for transmitting paging to such terminals.

Description

Method, apparatus and system for distinguishing a terminal in a power saving mode and transmitting a paging signal for waking a terminal operating in a power saving mode

The present invention relates to a next-generation wireless communication system, and in particular, a power saving mode operation procedure of a terminal for a system including one or more base stations and one or more terminals, and distinguishing terminals of a base station for transmitting paging to such terminals A method, a terminal recognition method, and a method, procedure, and system for transmitting paging information by a plurality of base stations in a certain area to an individual terminal.

Efforts are being made to develop an improved 5G communication system or pre-5G communication system in order to meet the increasing demand for wireless data traffic after commercialization of the 4G communication system. For this reason, the 5G communication system or the pre-5G communication system is called a system after the 4G network (Beyond 4G Network) communication system or the LTE system after (Post LTE). In order to achieve a high data rate, the 5G communication system is being considered for implementation in a very high frequency (mmWave) band (eg, such as a 60 gigabyte (60 GHz) band). In order to alleviate the path loss of radio waves and increase the propagation distance of radio waves in the ultra-high frequency band, in the 5G communication system, beamforming, massive MIMO, and Full Dimensional MIMO (FD-MIMO) are used. ), array antenna, analog beam-forming, and large scale antenna technologies are being discussed. In addition, for network improvement of the system, in the 5G communication system, an evolved small cell, an advanced small cell, a cloud radio access network (cloud radio access network: cloud RAN), an ultra-dense network (ultra-dense network) , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation Technology development is underway. In addition, in the 5G system, advanced coding modulation (ACM) methods such as FQAM (Hybrid FSK and QAM Modulation) and SWSC (Sliding Window Superposition Coding), and advanced access technologies such as Filter Bank Multi Carrier (FBMC), NOMA (non orthogonal multiple access), and sparse code multiple access (SCMA) are being developed.

On the other hand, the Internet is evolving from a human-centered connection network where humans create and consume information to an Internet of Things (IoT) network that exchanges and processes information between distributed components such as objects. Internet of Everything (IoE) technology, which combines big data processing technology through connection with cloud servers, etc. with IoT technology, is also emerging. In order to implement IoT, technology elements such as sensing technology, wired and wireless communication and network infrastructure, service interface technology, and security technology are required. , M2M), and MTC (Machine Type Communication) are being studied. In the IoT environment, an intelligent IT (Internet Technology) service that collects and analyzes data generated from connected objects and creates new values in human life can be provided. IoT is a field of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliance, advanced medical service, etc. can be applied to

Accordingly, various attempts are being made to apply the 5G communication system to the IoT network. For example, in technologies such as sensor network, machine to machine (M2M), and MTC (Machine Type Communication), 5G communication technology is implemented by techniques such as beam forming, MIMO, and array antenna. there will be The application of cloud radio access network (cloud RAN) as the big data processing technology described above can be said to be an example of convergence of 5G technology and IoT technology.

In the 5G system, support for various services is being considered compared to the existing 4G system. For example, the most representative services are the enhanced mobile broad band (eMBB), ultra-reliable and low latency communication (URLLC), and massive device-to-device communication service (mMTC). machine type communication), a next-generation broadcast service (eMBMS: evolved multimedia broadcast/multicast service), and the like. In addition, the system providing the URLLC service may be referred to as a URLLC system, the system providing the eMBB service may be referred to as an eMBB system, and the system providing the mMTC service may be referred to as an mMTC system. Also, the terms service and system may be used interchangeably.

The present disclosure is intended to solve at least the above-mentioned problems and/or disadvantages and to provide at least the advantages described below.

Accordingly, the present invention provides a power saving mode operation procedure of a terminal for a system including one or more base stations and one or more terminals, and a method of distinguishing a terminal of a base station for transmitting paging to such a terminal, a terminal recognition method, and An object of the present invention is to provide a method, procedure, and system for transmitting paging information by multiple base stations in a certain area to individual terminals.

According to an embodiment of the present invention, in a method of operating a base station in a wireless communication system, receiving beam measurement information from a terminal, and determining a change in a transmission beam of the base station for the terminal based on the beam measurement information and changing the transmission beam of the base station based on the relationship between the current reception beam of the terminal and the new transmission beam of the base station included in the beam measurement information.

In addition, according to an embodiment of the present invention, in the base station, receiving beam measurement information from a transceiver and a terminal for transmitting and receiving signals, and determining a transmission beam change of the base station for the terminal based on the beam measurement information and a control unit for controlling to change the transmission beam of the base station based on the relationship between the current reception beam of the terminal and the new transmission beam of the base station included in the beam measurement information.

In addition, according to an embodiment of the present invention, in a method of operating a terminal in a wireless communication system, performing beam measurement on at least one transmission beam of a base station and at least one beam of the terminal, based on the beam measurement and transmitting the beam measurement information to the base station and receiving downlink information transmitted from the new transmission beam of the base station, wherein the new transmission beam of the base station is the terminal of the terminal included in the beam measurement information. It is possible to provide a method characterized in that it is changed based on the relationship between the current reception beam and the new transmission beam of the base station.

In addition, according to an embodiment of the present invention, in the terminal, a transceiver for transmitting and receiving a signal and at least one transmission beam of the base station and at least one beam of the terminal perform beam measurement, and based on the beam measurement and a control unit for transmitting beam measurement information to the base station and controlling to receive downlink information transmitted from a new transmission beam of the base station, wherein the new transmission beam of the base station is included in the beam measurement information It is possible to provide a terminal characterized in that it is changed based on the relationship between the current reception beam and the new transmission beam of the base station.

It is an object of the present invention to provide a system, method, and apparatus for performing beam tracking and beam feedback operations in a beamforming-based system.

Another object of the present invention is to provide a system, method, and apparatus for performing beam tracking and beam feedback operations in a beamforming-based system.

Another object of the present invention is to provide a beam feedback and beam management method in a wireless system in which a base station and a terminal using multiple antennas exist.

In addition, another object of the present invention is to provide a beam feedback and tracking method in which a terminal informs a base station of beam measurement information through an indicator in a system and environment using multi-antenna-based beamforming.

Another object of the present invention is to provide a beam feedback and beam management method in a wireless system in which a base station and a terminal using multiple antennas exist.

Another aspect of the present invention provides a system including at least one base station and at least one terminal, wherein the terminal operates in a power saving state, and the base station identifies and recognizes an individual terminal and transmits a paging signal thereto. will be.

These and other aspects, features and advantages of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings.
1A shows an embodiment of a RAN Paging procedure.
1B shows an example of an operation procedure of a paging reception method of a power saving state operation terminal.
1C shows a method of using a new RNTI for RAN Paging.
1D shows various methods of configuring an RP-TMSI (or a new TMSI).
Figure 1e shows the RAN and CN paging procedure and operation of each terminal when RP-TMSI is added.
1f shows an embodiment using both RP-RNTI and RP-TMSI.
1G shows an example in which the last serving base station simplifies paging by using C-RNTI.
1H shows an example in which the last serving base station transmits a C-RNTI in a paging message.
1I shows an example of an environment in which CN Paging and RAN Paging coexist with different cycles and Pagin Occasion.
1j shows an example of an environment in which CN Paging and RAN Paging coexist with the same cycle and Pagin Occasion.
1K shows an embodiment of the Minimum/Additional SI modification Period operation.
11 shows an embodiment of SIU Update operation.
1M shows an embodiment of uplink transmission resource allocation in paging PDCCH for fast re-connection.
FIG. 1N shows another embodiment of uplink transmission resource allocation in paging PDCCH for fast re-connection.
FIG. 1o shows another embodiment of uplink transmission resource allocation in paging PDCCH for fast re-connection.
1p is a Paging PCH Config including UL-SCH. A fast network reconnection method using
1q shows an embodiment of allocating uplink transmission resources and adding indicators in paging PDCCH for fast re-connection.
1r shows another embodiment of allocating uplink transmission resources and adding indicators in paging PDCCH for fast re-connection.
1s shows another embodiment of allocating uplink transmission resources and adding indicators in paging PDCCH for fast re-connection.
1t is a Paging PCH Config including UL-SCH and Indicator. A fast network reconnection method using
1U is a diagram illustrating an example of an RNTI + Preamble transmission method.
1v is a Paging PCH Config including a Dedicated RACH Preamble. It is a diagram showing a fast network reconnection method using
1w is a diagram illustrating an example of a Paging Message + Preamble transmission method.
1x shows a fast network reconnection method using a paging message including a dedicated RACH preamble.
1y is a diagram illustrating a terminal according to an embodiment of the present invention.
1z is a diagram illustrating a base station according to an embodiment of the present invention.
2A is a diagram illustrating a multi-beam system according to an embodiment of the present invention.
2B is a diagram illustrating a frame structure for feeding back multi-beam IDs and beam measurement values according to an embodiment of the present invention.
2C is a diagram illustrating a frame structure for feeding back multiple beam IDs and beam measurement values according to an embodiment of the present invention.
2D is a diagram illustrating a frame structure for feeding back multiple beam IDs and beam measurement values according to an embodiment of the present invention.
2E is a diagram illustrating an example of beam change through beam feedback.
2F and 2G are diagrams illustrating frame structures for transmitting beam feedback.
2H is a view for explaining the operations of the base station and the terminal to change from the currently used base station beam to the (on, 1) base station beam for which the corresponding indicator is turned on.
FIG. 2i is a view for explaining the operations of the base station and the terminal when the indicator is an indicator indicating that the base station can freely change the BCI without sending the BCI to the terminal.
FIG. 2J is a diagram for explaining operations of a base station and a terminal in a method for transmitting a first beam feedback according to selection of a beam to be used during initial access. Referring to FIG.
2K and 2P are diagrams illustrating a method in which a UE attempts to transmit a beam recovery request when a certain condition2 condition is satisfied according to an embodiment of the present invention in association with an RLF operation.

BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present invention are described in detail with reference to the accompanying drawings, in which like reference numerals may be used to refer to like elements. It should be understood, however, that there is no intention to limit the specification to the specific form disclosed herein. Rather, this disclosure should be construed to cover various modifications, equivalents and/or alternatives of the embodiments of the present disclosure.

In this specification, the term "base station" may be used interchangeably with "eNB". Also, “terminal” may be used interchangeably with “user equipment (UE)”.

[Embodiment A: INACTIVE UE ID]

With the advent of smart phones, users' smart phone usage is increasing exponentially, and the demand for battery life increase for continuous smart phone use by these users is increasing. This means that an efficient power saving technology is required, and for this, the terminal needs to operate in a power saving mode. Various techniques have been proposed and standardized for efficient terminal power saving, to enable the terminal to operate in a power saving mode more frequently, and to re-establish a connection with a network more quickly.

Representative technologies for power saving in smartphones include Power Saving State UE operation that operates as a sub-state of RRC Connected State, Power Saving State UE operation that operates as a sub-state of RRC IDLE State, and a new RRC state. There are Power Saving State UE operation, LTE Lightly Connected State operation, 5G NR RRC_INACTIVE State operation, and WLAN (IEEE 802.11) Power Save Mode operation.

If there is no transmission/reception information for a certain period of time or more, or other conditions are satisfied, the UE transitions to a power saving state (LC: Lightly Connected State, INACTIVE: RRC_INACTIVE State). At this time, the difference from IDLE mode is that the base station and the terminal keep the network connection information (S1 information) and the terminal information of the terminal without discarding, and from the view of the core network, the terminal still appears to be connected (RRC_Connected) is the point. The reason for maintaining the S1 information in this way is to perform network reconnection of the terminal very quickly. In this way, the terminal operating in the power saving state gets up and reconnects to the network if there is information that needs to be transmitted, and when the base station receives any downlink information from the network, it gets up through paging of the base station and reconnects to the network.

In order to perform paging (RAN based paging) of the base station, a bundle of base stations transmitting such paging is defined as a RAN Paging Area, and the corresponding information is provided to the terminal. The UE, knowing the RAN Paging Area information, wakes up periodically during the power saving state operation, determines whether it is still within the RAN Paging Area it is aware of, and if it is within the RAN Paging Area, looks at the promised sub-frame for downlink paging information It must be determined whether there is If the UE leaves the RAN Paging Area while sleeping, the UE needs to re-establish a connection to a neighboring base station and perform RAN Paging Area Update.

1A shows an example of the structure of a core network, a base station, and a terminal for such RAN paging transmission according to an embodiment of the present disclosure.

In order to transmit paging information to the terminal operating in the power saving state as described above, a terminal identifier capable of specifying the terminal is required, and a procedure for transmitting a paging message including the identifier may be required.

In the case of IDLE mode Paging (= CN Paging) transmitted by the MME, a sub-frame in which Paging exists is specified using P-RNTI.

If a terminal to receive any paging exists, the P-RNTI value is included in the PDCCH (physical downlink control channel) of the sub-frame that the terminal periodically wakes up and receives on a predetermined paging occasion and is transmitted.

1B illustrates an example of an operation procedure of a paging reception method of a power saving state operation terminal according to an embodiment of the present disclosure.

Referring to FIG. 1B, in operation 1b-05, the base station may receive a paging message for a specific terminal from the MME.

In operation 1b-10, the base station transmits the P-RNTI to the PDCCH of the subframe that the corresponding terminal periodically wakes up and receives on a predetermined paging occasion.

Upon receiving the P-RNTI in operation 1b-15, the UE determines that the corresponding subframe includes a paging message transmitted to any UE.

In operation 1b-20, the base station transmits a paging message through a physical downlink shared channel (PDSCH) of the same subframe or a PDSCH of a subframe indicated by the PDCCH. The paging message may include a system architecture evolution (SAE)-temporary mobile subscriber identity (S-TMSI) or international mobile subscriber identity (IMSI) that is a unique ID within the MME of the terminal.

In operation 1b-25, the UE checks whether S-TMSI or IMSI, which is an identifier corresponding to itself, is included in the corresponding subframe. If it is included, proceed to operation 1b-30, if not, proceed to operation 1b-35. In operation 1b-30, the terminal performs an operation for network reconnection. In operation 1b-35, the UE resumes the sleep operation. The UE may perform a sleep operation until the next paging occasion.

<How to specify the RAN paging subframe by defining a new RNTI>

A method of defining a new RNTI different from the P-RNTI (RAN Paging RNTI: RP-RNTI) and enabling the base station to paging the terminal using this.

The base station may transmit the P-RNTI and/or the RP-RNTI through the PDCCH of a subframe that the corresponding terminal periodically wakes up and receives on a predetermined paging occasion. The corresponding transmission method may be a method of scrambling the CRC of the transmitted DCI. A UE receiving the PDCCH in one sub-frame can distinguish CN paging and RAN paging through P-RNTI and RP-RNTI, and P-RNTI and RP-RNTI are UEs corresponding to CN paging and RAN paging, respectively. can be distinguished as At this time, only terminals that have received their P-RNTI or RP-RNTI may additionally decode the PDSCH, and terminals that do not correspond to the P-RNTI or RP-RNTI may quickly return to sleep mode.

[Table 1] shows a new RNTI value, and [Table 2] shows an example of using the new RNTI.

In addition, FIG. 1C shows a new RNTI usage method for RAN Paging.

Referring to FIG. 1C , it includes a base station, a RAN paging terminal, and an IDLE terminal.

In operation 1c-05, the base station may receive a paging message for a specific terminal from the MME or a paging request including a paging message for a specific terminal and terminal ID information from the base station in the RAN paging area.

In operation 1c-10, the base station may transmit the RP-RNTI through the PDCCH of the subframe that is the paging occasion of the terminal. The base station may transmit the RP-RNTI to the RAN paging terminal and/or the IDLE terminal on the PDCCH of the subframe that is the paging occasion of the corresponding terminal.

Upon receiving the RP-RNTI, the IDLE terminal may recognize that the RP-RNTI is different from the P-RNTI in operation 1c-20 and resume the sleep operation. The IDLE UE may maintain a sleep state until the next paging occasion.

Upon receiving the RP-RNTI, the RAN paging terminal may confirm that the subframe receiving the RP-RNTI includes a paging message transmitted to a certain terminal in operation 1c-15.

In operation 1c-25, the base station transmits a paging message through the PDSCH of the same subframe as the subframe in which the RP-RNTI is transmitted or the subframe indicated by the PDCCH including the RP-RNTI. The paging message may include S-TMSI or IMSI, which is a unique ID within the MME of the UE. Operation 1c-25 may be performed simultaneously with operation 1c-10. That is, information corresponding to 1c-10 may be transmitted in the PDCCH of the same subframe, and information corresponding to operation 1c-25 may be transmitted in the PDSCH. This can be equally applied to other embodiments of the present invention.

In operation 1c-30, the RAN paging terminal checks whether its S-TMSI or IMSI is included in the paging message. If the paging message includes the S-TMSI or IMSI corresponding to the RAN paging terminal itself, proceed to operation 1c-40, and if the paging message does not include the S-TMSI or IMSI corresponding to the RAN paging terminal itself, 1c- Proceed to 45 action.

In operation 1c-40, the RAN paging terminal recognizes that the paging message is for itself and performs a network reconnection operation. In operation 1c-45, the RAN paging terminal recognizes that the paging message is not for itself and resumes the sleep operation. The RAN paging terminal may maintain a sleep state until the next paging occasion.

<How to distinguish RAN Paging by defining a new UE Specific ID>

A method of defining a new UE Specific ID different from S-TMSI and IMSI (RAN Paging TMSI: RP-TMSI), and using it to enable the base station to paging the UE.

A UE receiving a paging message through the PDSCH in one sub-frame may recognize that the corresponding paging message specifies itself operating as RAN paging.

[Table 3] shows the value of the PagingUE-Identity field including the new UE ID.

[Table 3]

The RP-TMSI may be a unique UE ID under the MME, a unique UE ID within the RAN Paging Area, or a unique UE ID within the eNB.

1D illustrates various methods of configuring an RP-TMSI (or a new TMSI) according to an embodiment of the present disclosure.

A method of configuring the RP-TMSI may be the same as that of FIG. 1D.

Figure 1e shows the RAN and CN paging procedure and operation of each terminal when RP-TMSI is added.

A procedure in the case where the system uses the same RNTI (P-RNTI) as the RNTI for CN Paging and RAN Paging and uses a method of distinguishing the UE by a subsequent UE unique ID is as shown in FIG. 1E .

Referring to FIG. 1e, in operation 1e-05, the base station receives a paging message for a specific terminal from the MME or a paging request including a paging message for a specific terminal and terminal ID information from the base station in the RAN paging area. can receive

In operation 1e-10, the base station may transmit the P-RNTI through the PDCCH of the subframe that is the paging occasion of the terminal. The base station may transmit the P-RNTI to the RAN paging terminal and/or the IDLE terminal on the PDCCH of a subframe that is a paging occasion of the corresponding terminal.

Upon receiving the P-RNTI, the RAN paging UE may confirm that the subframe receiving the P-RNTI includes a paging message transmitted to a certain UE in operation 1e-15. Upon receiving the P-RNTI, the IDLE UE may confirm that the subframe receiving the P-RNTI includes a paging message transmitted to any UE in operation 1e-15.

In operation 1e-25, the base station transmits a paging message through the PDSCH of the same subframe as the subframe in which the P-RNTI is transmitted or the subframe indicated by the PDCCH including the P-RNTI. The paging message may include RP-TMSI, S-TMSI, or IMSI, which is a unique ID within the MME of the UE.

In operation 1e-30, the RAN paging terminal checks whether its RP-TMSI or IMSI is included in the paging message. If the paging message includes the RP-TMSI or IMSI corresponding to the RAN paging terminal itself, proceed to operation 1e-35, and if the paging message does not include the RP-TMSI or IMSI corresponding to the RAN paging terminal itself, 1e- Proceed with 40 moves.

In operation 1e-35, the RAN paging terminal recognizes that the paging message is for itself and performs a network reconnection operation. In operation 1e-40, the RAN paging terminal recognizes that the paging message is not for itself and resumes the sleep operation. The RAN paging terminal may maintain a sleep state until the next paging occasion.

In operation 1e-45, the IDLE terminal checks whether its S-TMSI or IMSI is included in the paging message. If the paging message includes the S-TMSI or IMSI corresponding to the IDLE terminal itself, proceed to operation 1e-50, and if the paging message does not include the S-TMSI or IMSI corresponding to the IDLE terminal itself, operation 1e-55 proceed to

In operation 1e-50, the IDLE terminal recognizes that the paging message is for itself and performs a network reconnection operation. In operation 1e-55, the IDLE terminal recognizes that the paging message is not for itself and resumes the sleep operation. The IDLE UE may maintain a sleep state until the next paging occasion.

<How to use both the new RNTI and the new UE Specific ID>

1f shows an embodiment using both RP-RNTI and RP-TMSI.

A UE operation procedure in the case of performing RAN paging using the proposed new RNTI (RP-RNTI) and new UE Specific ID (RP-TMSI) at the same time is shown in FIG. 1F.

Referring to FIG. 1f, in operation 1f-05, the base station receives a paging message for a specific terminal from the MME or a paging request including a paging message for a specific terminal and terminal ID information from the base station in the RAN paging area. can receive

In operation 1f-10, the base station may transmit the RP-RNTI through the PDCCH of the subframe that is the paging occasion of the terminal. The base station may transmit the RP-RNTI to the RAN paging terminal and/or the IDLE terminal on the PDCCH of the subframe that is the paging occasion of the corresponding terminal.

Upon receiving the RP-RNTI, the IDLE terminal may recognize that the RP-RNTI is different from the P-RNTI in operation 1f-20 and resume the sleep operation. The IDLE UE may maintain a sleep state until the next paging occasion.

The RAN paging terminal that has received the RP-RNTI may confirm that the subframe that has received the RP-RNTI includes a paging message transmitted to a certain terminal in operation 1f-15.

In operation 1f-25, the base station transmits a paging message through the PDSCH of the same subframe as the subframe in which the RP-RNTI is transmitted or the subframe indicated by the PDCCH including the RP-RNTI. The paging message may include RP-TMSI or IMSI, which is a unique ID within the MME of the UE.

In operation 1f-30, the RAN paging terminal checks whether its RP-TMSI or IMSI is included in the paging message. If the paging message includes the RP-TMSI or IMSI corresponding to the RAN paging terminal itself, proceed to operation 1f-40, and if the paging message does not include the RP-TMSI or IMSI corresponding to the RAN paging terminal itself, 1f- Proceed to 45 action.

In operation 1f-40, the RAN paging terminal recognizes that the paging message is for itself and performs a network reconnection operation. In operation 1f-45, the RAN paging terminal recognizes that the paging message is not for itself and resumes the sleep operation. The RAN paging terminal may maintain a sleep state until the next paging occasion.

<Method for allocating a unique UE ID in the RAN Paging Area for base stations in the RAN Paging Area>

(One). How to set up one admin and assign it to admins

(A). Select one base station

(B). MME assignment

(2). How to randomly allocate without a management principal

(3). How base stations share the Unique ID Pool and allocate within it

(4). How base stations allocate IDs distributedly and mutually announce them

(A). Conflict resolution required

<The last serving base station and the neighboring base station paging the terminal using different RNTIs>

In the case of the last serving base station that the terminal accessed last before transitioning to the power saving state, it retains the C-RNTI of the terminal as it is, and also maintains the S1 connection for information exchange between the terminal and the Core Network. Using this feature, the last serving base station can perform more efficient paging using a method differentiated from other base stations within the RAN Paging Area of the corresponding terminal.

For this purpose, the operation of the base station and the terminal is as follows: The terminal operating in the power saving state wakes up periodically and checks the promised sub-frame at the promised time to check whether paging information has been received by itself. To this end, the terminal periodically wakes up and resets downlink synchronization before receiving the sub-frame, selects a cell to receive the sub-frame (which may be the same as or similar to the cell reselection operation of IDLE mode). will choose

1G illustrates an example in which the last serving base station simplifies paging by using C-RNTI according to an embodiment of the present disclosure.

Referring to FIG. 1G, base stations in the RAN Paging Area other than the last serving base station to which the terminal was connected cannot use the C-RNTI of the corresponding terminal. The serving base station may perform paging using the C-RNTI that the terminal knows. At this time, the C-RNTI may be included in the PDCCH and transmitted (by scrambling the DCI CRC), and the Resource Scheduling size (RB size) in the PDCCH including the C-RNTI may be set to 0. As such, the terminal operating in the power saving mode periodically wakes up and receives a sub-frame in a paging occasion. If a PDCCH message including C-RNTI (scrambled with C-RNTI) exists, there is downlink data to be received. (assuming that paging has received it successfully), it can try to reconnect to the network. In this case, as an additional condition other than C-RNTI, when the resource scheduling size is 0, the UE may perform the above operation.

Referring to FIG. 1G, in operation 1g-05, the last serving base station may receive a paging message for a specific terminal from the MME.

In operation 1g-10, the last serving base station may transmit a paging request including a specific terminal message and terminal ID information to the base station in the RAN PA (paging area).

In operation 1g-15, the last serving base station may transmit a C-RNTI to a terminal in the area of the last serving base station through the PDCCH of a subframe that is a paging occasion of the corresponding terminal. In this case, the RB size in the PDCCH including the corresponding C-RNTI may be set to 0.

In operation 1g-20, the base station in the RAN PA may transmit a P-RNTI or an RP-RNTI to a terminal in its own area. The base station in the RAN PA may transmit the RP-RNTI or P-RNTI to the PDCCH of the subframe that is the paging occasion of the terminal.

The terminal in the last serving base station region that has received the message in the PDCCH including the C-RNTI or C-RNTI in which the RB size is set to 0 may recognize that it is paging itself in the corresponding subframe in operation 1g-25. If a PDCCH message (scrambled with C-RNTI) including C-RNTI exists, the UE recognizes that there is downlink data to be received (determining that paging has been successfully received), and in operation 1g-40 You can try to reconnect to the network.

The UE that has received the P-RNTI or RP-RNTI can confirm that the subframe that receives the P-RNTI or RP-RNTI in operation 1g-30 includes a CN paging message or a RAN paging message transmitted to any UE. .

In operation 1g-35, the base station transmits a paging message through the PDSCH of the same subframe as the subframe in which the P-RNTI or RP-RNTI is transmitted or the subframe indicated by the PDCCH including the P-RNTI or RP-RNTI. The paging message may include RP-TMSI, S-TMSI, or IMSI, which is a unique ID within the MME of the UE.

In operation 1g-45, the terminal within the base station area within the RAN PA checks whether its RP-TMSI, S-TMSI, or IMSI is included in the paging message. If the paging message includes the RP-TMSI, S-TMSI, or IMSI corresponding to the terminal itself, proceed to operation 1g-50, and the RP-TMSI, S-TMSI, or IMSI corresponding to the terminal itself is not included in the paging message. In this case, proceed to 1g-55 operation.

In operation 1g-50, the terminal recognizes that the paging message is for itself and performs a network reconnection operation. In operation 1g-55, the UE recognizes that the paging message is not for itself and resumes the sleep operation. The UE may maintain a sleep state until the next paging occasion.

1ha and 1hb illustrate an example in which the last serving base station transmits a C-RNTI in a paging message according to an embodiment of the present disclosure.

1ha and 1hb, when the base stations in the RAN Paging Area paging the terminal using P-RNTI, RP-RNTI, etc., and transmitting a Paging Message of the PDSCH for specifying the terminal, the last serving base station knows the terminal. An example of transmission including C-RNTI can be considered. At this time, other base stations in the RAN Paging Area may use RP-TMSI, S-TMSI, IMSI, etc. instead of C-RNTI.

In operation 1h-05, the last serving base station may receive a paging message for a specific terminal from the MME.

In operation 1h-10, the last serving base station may transmit a paging request including a specific terminal message and terminal ID information to a base station in a RAN PA (paging area).

In operation 1h-15, the last serving base station may transmit a P-RNTI or RP-RNTI to a terminal in the area of the last serving base station through the PDCCH of a subframe that is a paging occasion of the corresponding terminal. In operation 1h-20, the base station in the RAN PA may transmit a P-RNTI or an RP-RNTI to a terminal in its own area. The base station in the RAN PA may transmit the RP-RNTI or P-RNTI to the PDCCH of the subframe that is the paging occasion of the terminal. - It can be confirmed that the subframe receiving the RNTI or RP-RNTI includes a CN paging message or a RAN paging message transmitted to a certain terminal. The UE that has received the P-RNTI or RP-RNTI can confirm that the subframe that receives the P-RNTI or RP-RNTI includes a CN paging message or a RAN paging message transmitted to any UE in operation 1h-30. .

In operation 1h-35, the last serving base station transmits a paging message through the PDSCH of the same subframe as the subframe in which the P-RNTI or RP-RNTI is transmitted or the subframe indicated by the PDCCH including the P-RNTI or RP-RNTI. do. The paging message may include a C-RNTI.

In operation 1h-45, the terminal within the area of the last serving base station checks whether C-RNTI, which is the terminal ID, is included in the paging message. If the C-RNTI is included in the paging message, it proceeds to operation 1h-50, and if not included, proceeds to operation 1h-55. In operation 1h-50, the UE recognizes that the paging message is for itself and performs a network reconnection operation. In operation 1h-55, the UE recognizes that the paging message is not for itself and resumes the sleep operation. The UE may maintain the sleep state until the next paging occasion.

In operation 1h-40, the base station in the RAN PA transmits a paging message through the PDSCH of the same subframe as the subframe in which the P-RNTI or RP-RNTI is transmitted or the subframe indicated by the PDCCH including the P-RNTI or RP-RNTI. send. The paging message may include RP-TMSI, S-TMSI, or IMSI, which is a unique ID within the MME of the UE.

In operation 1h-60, the terminal within the base station area within the RAN PA checks whether its RP-TMSI, S-TMSI, or IMSI is included in the paging message. If the paging message includes the RP-TMSI, S-TMSI or IMSI corresponding to the terminal itself, proceed to operation 1h-65, and the RP-TMSI, S-TMSI or IMSI corresponding to the terminal itself is not included in the paging message. In this case, proceed to operation 1h-70.

In operation 1h-65, the UE recognizes that the paging message is for itself and performs a network reconnection operation. In operation 1h-70, the UE recognizes that the paging message is not for itself and resumes the sleep operation. The UE may maintain a sleep state until the next paging occasion.

<How to distinguish RAN based paging by adding an indicator>

Instead of using the new RNTI and TMSI, there may be a method of using RNTI and TMSI and adding an indicator to another field to distinguish paging.

A method of adding a 1-bit indicator to the DCI in the PDCCH is as follows.

[Table 4] is a One Bit RAN Paging indicator for DCI format 1A/1C, and [Table 5] is a Two bits RAN Paging indicator for DCI format 1A/1C.

A method of distinguishing between RAN Paging and CN Paging by adding a 1-bit indicator in addition to the UE Identity in the PDSCH is as follows. [Table 6] shows One Bit RAN Paging indicator after PagingUE-Identity

[Table 6]

The terminal receiving this using the indicator can distinguish whether the corresponding PagingUE-Identity and the paging message is RAN paging or CN paging, and performs an operation according to its own state, and paging transmitted for other state purposes can be ignored. .

<New RAN Paging Discontinuous Reception (DRX) Configuration>

In the new power saving state, the UE performs an operation of sleeping and waking up with a certain rule similar to the operation of the IDLE mode. This discontinuous reception operation of the terminal is called DRX, and the terminal DRX operation in this power saving state should be signaled and controlled by the base station.

The DRX Cycle of such a UE may be signaled and controlled in the following way.

[Table 7] is INACTIVE Paging Cycle under DRX-Config, and [Table 8] is INACTIVE Paing Cycle under PDCCH-Config.

[Table 7]

[Table 8]

In an environment where two types of paging, CN paging and ran paging, coexist, when RAN paging is newly defined and signaled as described above, the system (base station and terminal) CN paging having different paging occasions and paging cycles (cycles) and RAN paging can be configured and used. In this case, the terminal operating in the Power Saving State may use only the RAN paging period, and the terminal operating in the IDLE mode may use only the CN paging period. Additionally, a terminal desiring more frequent and faster paging reception, such as SI update or radio link failure recovery (cell reselection), may look at both paging occasions regardless of the state of the terminal. Of course, in this case, power consumption may be added compared to the case of receiving only one type of paging due to the frequent paging reception of the terminal.

1I shows an example of an environment in which CN Paging and RAN Paging coexist with different cycles and Pagin Occasion according to an embodiment of the present disclosure.

config so that CN paging and RAN paging have different cycles. An example of a UE that is and operates is shown in FIG. 1I.

On the other hand, config CN Paging and Ran Paging in the same cycle. and terminals having different states (IDLE and power saving) may be awake at the same time. In this case, if a new RAN Paging Drx config exists, of course, the corresponding value can be set to be the same as that of CN Paging, and the new DRX config. It is also possible to use CN Paging Config for RAN Paging without adding .

config to recycle this embodiment and CN Paging to RAN Paging. Examples of [Fig. 1j] and [Table 9] are described.

1J shows an example of an environment in which CN Paging and RAN Paging coexist with the same period and Pagin Occasion, and [Table 9] is RadioResourceConfigCommon field descriptions.

[Table 9]

As another method, an indicator may be provided to inform the UE that CN Paging and RAN Paging in PCCH Config are the same.

[Table 10] is INACTIVE Paing Cycle under PDCCH-Config with indicator, and [Table 11] is RadioResourceConfigCommon field descriptions.

[Table 10]

[Table 11]

<How the terminal, base station, and network delete terminal information>

The unique information and network connection information of the terminal operating in the power saving state should be deleted from the terminal and from the base station when the terminal transitions to the IDLE state or when the network can no longer be used due to an unavoidable change. Such terminal and network information deletion time may be a case where various conditions are satisfied, and these conditions are as follows:

1) When the UE is re-connected to the other cell

- When the UE itself is re-connected to the other cell and reconfigured

- When the other cell transmitted a signal to the last serving cell that the UE is re-connected.

2) When the UE updated paging area

- When the UE itself is moved out of the RAN paging area and successfully updated paging area

- When the other cell transmitted a signal to the last serving cell that the UE is updated RAN paging area.

3) When the UE state changes into IDLE mode (UE operation)

- By the eNB indication signal (RRC message, MAC message, …)

- By the channel quality degradation is measured

-- if RSRP, RSRQ, CQI, SINR, SNR, of the serving channel < threshold1

-- if the current measured RSRP, RSRQ, CQI, SINR, SNR, of the serving channel < last measured RSRP, RSRQ, CQI, SINR, SNR, of the serving channel - threshold2

- By a timer expiration

-- Timer started at the last successful data tx/rx , at the last channel measurement, at the last channel measurement result > threshold, …

4) When the eNB detects a UE is no longer in the power saving state

- By the number of paging retransmission reaches the max. threshold3

- By the channel quality degradation is measured

-- if RSRP, RSRQ, CQI, SINR, SNR, of the serving channel < threshold1

-- if the current measured RSRP, RSRQ, CQI, SINR, SNR, of the serving channel < last measured RSRP, RSRQ, CQI, SINR, SNR, of the serving channel - threshold2

- By a timer expiration

- By a number of NACK (or No ACK) responses reaches the max. threshold4

<How to send paging for System Information Update>

In 5G, system information can be divided into two or more components. Of these, the minimum system information for network access that is periodically transmitted may be called Minimum SI, and system information that can be transmitted through other broadcasting or unicasting (on-demand) systems may be referred to as additional SI. In this case, the Minimum SI and the Additional SI may have the same update period, or only one of them may be updated.

In order to update the different system information, in the next standard, two or more different system information update periods may be set. In this case, different system information update periods may be as follows.

[Table 12] is Minimum/Additional SI update periods in TS36.331, and [Table 13] is Minimum/Additional SI update periods in TS36.331.

[Table 12]

[Table 13]

1K illustrates an embodiment of Minimum/Additional SI modification Period operation according to an embodiment of the present disclosure.

In the operation of the period for updating the different system information, different periods may be individually allocated so as not to overlap at different times, and an embodiment of this may be the same as in FIG. 1K . If the system information update and change notification for this are made at such a non-overlapping time, the terminal can update only the corresponding information in a corresponding period after receiving a specific change notification, so that it is not necessary to update all system information. In addition, the operation of such a period may be assigned so that different periods overlap at the same time.

In order to update the different system information, the system may transmit paging messages including a change notification in the period immediately before the modification period for actually updating the system information. This paging message may be CN paging, RAN paging, or both.

Terminals connected to the network, operating in power saving mode within the network, or camped in the network receive this paging information and update the system information in the next modification period.

At this time, the system information update (change) notification included in the paging message may be divided into minimum SI and additional SI purposes, respectively, and this may be reflected in terminal operation as follows.

[Table 14] is Minimum/Additional SI update of UE in TS36.331.

[Table 14]

As another method, if the reception of additional SI information is operated by the UE request on-demand, the following is the case:

[Table 15] is Minimum/Additional SI update of UE in TS36.331.

[Table 15]

In addition to this, in receiving paging information including a change notice indicating that the system information will be changed soon, a case in which each paging information receiving period is smaller than a modification period in which a change notice is continuously transmitted can be considered. Yes (Paging Cycle < modification period). In this case, the terminal receives the paging message including the same change notification every time, and this information is redundant and causes power consumption of the terminal. Therefore, if the terminal decodes only the paging message including the first notification, and then, among the paging messages transmitted within the same modification period, paging messages including only the same SI update change notification can be distinguished and ignored, the power of the terminal can save

To this end, an embodiment of the present invention proposes the following new paging information identifier (SIU-RNTI).

SIU-RNTI is used if the paging is only for SI update notification

- If the paging contains other info. such as data paging, SIU-RNTI can not be used (P-RNTI can be used)

- UE which received SI update once, can ignore the other SIU-RNTI during the same BCCH modification period.

[Table 16] shows new RNTI values for SI Update according to an embodiment of the present disclosure, and FIG. 11 shows an embodiment of SIU Update operation.

[Table 16]

<How a terminal operating in a power saving state can quickly reconnect to the network>

In order for the terminal operating in the power saving state to quickly reconnect to the network, there may be various methods. The methods considered in this patent are methods that can be used when the uplink and downlink channel characteristics are similar and synchronization is similar because the distance between the transmitter and receiver is relatively short, and occupies uplink resources in downlink paging information and , this is a method in which the UE directly performs uplink transmission without a special uplink synchronization operation (e.g., RACH). The detailed procedure is as follows:

A method of allocating uplink transmission resources in paging PDCCH for fast re-connection is as follows.

The base station transmits the UL-SCH resource reservation for the terminal's response (or for the terminal's resume request transmission) in the paging PDCCH, and the terminal that receives it recognizes that the corresponding paging message is the terminal's network reconnection request (implicit indication via UL-SCH config.)

According to an embodiment of the present invention, C-RNTI + Paging PCH + UL SCH configuration may be applied.

1M shows an embodiment of allocation of uplink transmission resources in paging PDCCH for fast re-connection according to an embodiment of the present invention.

A base station with a previously used (or promised) C-RNTI with the terminal (e.g., the last serving eNB) transmits a paging PDCCH using the C-RNTI to access the network to the terminal operating in the corresponding power saving state. request to resume. (connection resume)

At this time, the UL-SCH config resource is temporally paging PCH config. It should be allocated after 3 TTI or more than the paging message transmission resource allocated by .

Upon receiving the message, the UE receives paging information through the paging PCH and transmits a connection resume request through the UL-SCH.

When the connection resume request transmission/reception is successfully completed, the network and the terminal immediately recognize that the connection has been completed, and the terminal state transitions to RRC_CONNECTED.

According to an embodiment of the present disclosure, C-RNTI + UL SCH configuration may be applied.

1N illustrates another embodiment of allocation of uplink transmission resources in paging PDCCH for fast re-connection according to an embodiment of the present disclosure.

A base station with a previously used (or promised) C-RNTI with the terminal (e.g., the last serving eNB) transmits a paging PDCCH using the C-RNTI to access the network to the terminal operating in the corresponding power saving state. request to resume. (connection resume)

Upon receiving the message, the UE transmits a connection resume request to the UL-SCH.

When the connection resume request transmission/reception is successfully completed, the network and the terminal immediately recognize that the connection has been completed, and the terminal state transitions to RRC_CONNECTED.

According to an embodiment of the present disclosure, RNTI + Paging PCH + UL SCH configuration may be applied.

FIG. 1o shows another embodiment of allocation of uplink transmission resources in paging PDCCH for fast re-connection according to an embodiment of the present disclosure.

By transmitting the paging PDCCH using the RNTI, the base station requests the terminal operating in the corresponding power saving state to resume access to the network. (connection resume)

At this time, the UL-SCH config resource is temporally paging PCH config. It should be allocated after 3 TTI or more than the paging message transmission resource allocated by .

Upon receiving the message, the UE receives the paging information through the paging PCH and, if its UE specific id is included in the received information, transmits a connection resume request to the UL-SCH.

When the connection resume request transmission/reception is successfully completed, the network and the terminal immediately recognize that the connection has been completed, and the terminal state transitions to RRC_CONNECTED.

1P is a Paging PCH Config including a UL-SCH according to an embodiment of the present disclosure; A fast network reconnection method using

Referring to FIG. 1P, the system includes a base station and a terminal. The terminal may be a terminal in a light connection (LC) state or an inactive state.

In operation 1p-05, the base station transmits a paging PDCCH using RNTI to the terminal to the terminal. The RNTI may be at least one of P-RNTI, C-RNTI, or RP-RNTI, as described in each of the above embodiments. The paging PDCCH may include a paging PCH config and may include a UL-SCH config. UL-SCH config resource is paging PCH config. It may be allocated to a subframe or TTI that is temporally later than the paging message transmission resource allocated by . For example, the UL-SCH resource may be allocated 3 TTI or more later than the paging message transmission resource.

In operation 1p-10, the base station may transmit a paging message to the terminal. The paging message may include a terminal identifier. The terminal identifier may include at least one of IMSI, S-TMSI, C-RNTI, RP-TMSI, and the like.

In operation 1p-15, the terminal receives paging information through the paging PCH, and checks whether its own terminal identifier is included in the received information.

If the terminal does not include its own terminal identifier, it proceeds to operation 1p-20. In operation 1p-20, the UE performs a sleep operation until the next paging occasion.

If the terminal includes its own terminal identifier, it proceeds to operation 1p-25. In operation 1p-25, the UE transmits an RRC connection resume request through the UL-SCH. The UL-SCH transmission resource may use the UL-SCH resource allocated in operation 1p-10.

In operation 1p-30, the base station may transmit a random access response (RAR) and RRC connection resume to the terminal. The UE may receive the RAR through the PDSCH. When the transmission/reception of RRC Connection resume request and RRC connection resume is successfully completed through the above process, the network and the terminal immediately recognize that the connection has been completed, and the terminal state can be transitioned to RRC_CONNECTED.

A method of allocating uplink transmission resources in the paging PDCCH for fast re-connection and adding an indicator will be described below.

The base station transmits the UL-SCH resource reservation for the terminal's response (or for the terminal's resume request transmission) in the paging PDCCH, and transmits it including an indicator requesting reconnection to the terminal using the resource. Upon receiving this, the UE recognizes that the message is a request for network reconnection from the UE (explicit indication). At this time, the corresponding indicator may be included in the UL-SCH config.

According to an embodiment of the present disclosure, C-RNTI + Paging PCH + UL SCH configuration may be applied.

1q illustrates an example of allocating uplink transmission resources and adding an indicator in a paging PDCCH for fast re-connection according to an embodiment of the present disclosure.

A base station with a previously used (or promised) C-RNTI with the terminal (e.g., the last serving eNB) transmits a paging PDCCH using the C-RNTI to access the network to the terminal operating in the corresponding power saving state. request to resume. (connection resume)

At this time, the UL-SCH config resource is temporally paging PCH config. It should be allocated after 3 TTI or more than the paging message transmission resource allocated by .

Upon receiving the message, the UE receives paging information through the paging PCH, and if the reconnection request indicator is a promised value (usually 1), it transmits a connection resume request to the UL-SCH.

When the network reconnection request transmission/reception is successfully completed, the network and the terminal immediately recognize that the connection has been completed, and the terminal state transitions to RRC_CONNECTED.

According to an embodiment of the present disclosure, C-RNTI + UL SCH configuration may be applied.

* FIG. 1r shows another embodiment of allocating uplink transmission resources and adding indicators in paging PDCCH for fast re-connection according to an embodiment of the present disclosure.

A base station with a previously used (or promised) C-RNTI with the terminal (e.g., the last serving eNB) transmits a paging PDCCH using the C-RNTI to access the network to the terminal operating in the corresponding power saving state. request to resume. (connection resume)

Upon receiving the message, if the reconnection request indicator is a promised value (usually 1), the UE transmits a connection resume request to the UL-SCH.

When the network reconnection request transmission/reception is successfully completed, the network and the terminal immediately recognize that the connection has been completed, and the terminal state transitions to RRC_CONNECTED.

According to an embodiment of the present disclosure, P-RNTI + Paging PCH + UL SCH configuration may be applied

1S shows another embodiment of allocating uplink transmission resources and adding an indicator in a paging PDCCH for fast re-connection according to an embodiment of the present disclosure.

By transmitting the paging PDCCH using the RNTI, the base station requests the terminal operating in the corresponding power saving state to resume access to the network. (connection resume)

At this time, the UL-SCH config resource is temporally paging PCH config. It should be allocated after 3 TTI or more than the paging message transmission resource allocated by .

Upon receiving the message, the UE receives the paging information through the paging PCH, and if the reconnection request indicator is a promised value (usually 1) and if the received information includes its UE specific id, the UL-SCH The router sends a connection resume request.

When the network reconnection request transmission/reception is successfully completed, the network and the terminal immediately recognize that the connection has been completed, and the terminal state transitions to RRC_CONNECTED.

1T is a Paging PCH Config including a UL-SCH and an indicator according to an embodiment of the present disclosure; A fast network reconnection method using

Referring to FIG. 1T , the system includes a base station and a terminal. The terminal may be a terminal in a light connection (LC) state or an inactive state.

In operation 1t-05, the base station transmits the paging PDCCH using the RNTI to the terminal to the terminal. The RNTI may be at least one of P-RNTI, C-RNTI, or RP-RNTI, as described in each of the above embodiments. The paging PDCCH may include a paging PCH config, and may include a UL-SCH config and a connection request indicator (or a connection resume request indicator). UL-SCH config resource is paging PCH config. It may be allocated to a subframe or TTI that is temporally later than the paging message transmission resource allocated by . For example, the UL-SCH resource may be allocated 3 TTI or more later than the paging message transmission resource.

In operation 1t-10, the base station may transmit a paging message to the terminal. The paging message may include a terminal identifier. The terminal identifier may include at least one of IMSI, S-TMSI, C-RNTI, RP-TMSI, and the like.

In operation 1t-15, the terminal receives paging information through the paging PCH, and checks whether or not its own terminal identifier is included in the received information.

If the terminal does not include its own terminal identifier, it proceeds to operation 1t-20. In operation 1t-20, the UE performs a sleep operation until the next paging occasion.

If the terminal includes its own terminal identifier, it proceeds to operation 1t-25. In operation 1t-25, if the reconnection request indicator is a promised value (usually 1), the UE transmits an RRC connection resume request through the UL-SCH. The UL-SCH transmission resource may use the UL-SCH resource allocated in operation 1t-10.

In operation 1t-30, the base station may transmit a random access response (RAR) and RRC connection resume to the terminal. The UE may transmit the RAR through the PDSCH. When the transmission/reception of the RRC Connection resume request and the RRC connection resume is successfully completed through the above process, the network and the terminal immediately recognize that the connection has been completed, and the terminal state can be transitioned to RRC_CONNECTED.

A method of allocating a dedicated resource (time, frequency, code (Preamble)) that can be used for a limited uplink access request so that the corresponding terminal can quickly access the network

RNTI + Preamble transmission method

1U is a diagram illustrating an RNTI + Preamble transmission method.

The corresponding RNTI receiving terminals, if their UE specific id is included in the received information, start the RACH using the dedicated preamble to indicate that the corresponding RACH is the RACH for uplink reconnection request.

Upon receiving the Dedicated RACH Preamble, the base station recognizes that the corresponding terminal requests network reconnection, and reconfigures and resumes the connection.

1v is a Paging PCH Config including a Dedicated RACH Preamble. It is a diagram showing a fast network reconnection method using

Referring to FIG. 1V , the system includes a base station and a terminal. The terminal may be a terminal in a light connection (LC) state or an inactive state.

In operation 1v-05, the base station transmits the paging PDCCH using the RNTI to the terminal to the terminal. The RNTI may be at least one of P-RNTI, C-RNTI, or RP-RNTI, as described in each of the above embodiments. The paging PDCCH may include a paging PCH config and may include a dedicated RACH preamble.

In operation 1v-10, the base station may transmit a paging message to the terminal. The paging message may include a terminal identifier. The terminal identifier may include at least one of IMSI, S-TMSI, C-RNTI, RP-TMSI, and the like.

In operation 1v-15, the terminal receives paging information through the paging PCH, and checks whether or not its own terminal identifier is included in the received information.

If the terminal does not include its own terminal identifier, it proceeds to operation 1v-20. In operation 1p-20, the UE performs a sleep operation until the next paging occasion.

If the terminal includes its own terminal identifier, it proceeds to operation 1v-25. In operation 1v-25, the UE starts the RACH using the dedicated preamble, and through this, the UE may indicate that the RACH is the RACH for the RRC connection resume request.

Upon receiving the dedicated RACH preamble, the base station recognizes that the terminal performs a network reconnection request, and re-establishes the connection with the terminal in operation 1v-30 and resumes the connection with the terminal. The base station may transmit a random access response (RAR) and RRC connection resume to the terminal. The UE may transmit the RAR through the PDSCH. When the transmission/reception of the RRC Connection resume request and the RRC connection resume is successfully completed through the above process, the network and the terminal immediately recognize that the connection has been completed, and the terminal state can be transitioned to RRC_CONNECTED.

A Paging Message + resource (time, frequency, code (Preamble)) transmission method is described below.

1w is a diagram illustrating a Paging Message + Preamble transmission method.

Terminals that have received the paging message as the paging PCH, if their UE specific id is included in the received information, start the RACH using a dedicated resource to indicate that the RACH is the RACH for the uplink reconnection request.

Upon receiving the Dedicated RACH Preamble, the base station recognizes that the corresponding terminal requests network reconnection, and reconfigures and resumes the connection.

1x shows a fast network reconnection method using a paging message including a dedicated RACH preamble.

Referring to FIG. 1x, the system includes a base station and a terminal. The terminal may be a terminal in a light connection (LC) state or an inactive state.

In operation 1x-05, the base station transmits a paging PDCCH using RNTI to the terminal to the terminal. The RNTI may be at least one of P-RNTI, C-RNTI, or RP-RNTI, as described in each of the above embodiments. The paging PDCCH may include a paging PCH config.

In operation 1x-10, the base station may transmit a paging message to the terminal. The paging message may include a terminal identifier. The terminal identifier may include at least one of IMSI, S-TMSI, C-RNTI, RP-TMSI, and the like. The paging message may include a dedicated preamble. Alternatively, a dedicated preamble may be transmitted together with the paging message.

In operation 1x-15, the terminal receives paging information through the paging PCH, and checks whether or not its own terminal identifier is included in the received information.

If the terminal does not include its own terminal identifier, it proceeds to operation 1x-20. In operation 1x-20, the UE performs sleep operation until the next paging occasion.

If the terminal includes its own terminal identifier, it proceeds to operation 1x-25. In operation 1x-25, the UE starts the RACH using the dedicated preamble, and through this, the UE may indicate that the RACH is the RACH for the RRC connection resume request.

Upon receiving the dedicated RACH preamble, the base station recognizes that the terminal performs a network reconnection request, and re-establishes the connection with the terminal in operation 1x-30 and resumes the connection with the terminal. The base station may transmit a random access response (RAR) and RRC connection resume to the terminal. The UE may transmit the RAR through the PDSCH. When the transmission/reception of RRC Connection resume request and RRC connection resume is successfully completed through the above process, the network and the terminal immediately recognize that the connection has been completed, and the terminal state can be transitioned to RRC_CONNECTED.

<Direct transmission of DL data using RNTI>

When short information is transmitted in downlink to a terminal operating in a power saving state, the network specifies a terminal using a known C-RNTI (or another new RNTI), and allocates downlink resources to the terminal to provide information can be sent

At this time, if the terminal does not need to synchronize uplink through random access, the base station allocates an uplink ACK/NACK resource to downlink transmission, receives a response from the terminal, and performs retransmission and HARQ operation for DL transmission. can increase the success rate.

At this time, if the terminal needs to synchronize uplink through random access, the base station can increase the success rate by repeatedly transmitting downlink transmission a predetermined number of times or more using repetition.

1y is a diagram illustrating a terminal according to an embodiment of the present invention.

Referring to FIG. 1y, the terminal may include a transceiver 1y-10 and a control unit 1y-30 for transmitting and receiving signals. Through the transceiver 1y-10, the terminal may transmit and/or receive signals, information, messages, and the like. The controller 1y-30 may control the overall operation of the terminal. The controller 1y-30 may include at least one processor. The controller 1y-30 may control the operation of the terminal described with reference to FIGS. 1A to 1X . The controller 1y-30 may include at least one processor.

In addition, the control unit 1y-30 receives the beam feedback trigger condition, determines whether the beam feedback trigger condition is satisfied, and if it is determined that the beam feedback trigger condition is satisfied, the MAC (medium access control) layer of the terminal can trigger beam feedback and control to transmit a MAC CE (control element) including beam feedback information based on the beam feedback trigger. The beam feedback trigger condition may include a case in which a channel measurement value of at least one beam is greater than a sum of a preset threshold value and a channel measurement value of a current serving beam.

In addition, if the uplink of the terminal is synchronized, the controller 1y-30 may control to transmit the beam feedback information by using the uplink allocation resource received through a scheduling request (SR) procedure. have. The UE may transmit an SR and receive information on resources allocated for beam feedback based on the SR transmission. Resource allocation may be performed periodically or aperiodically.

Also, if the uplink of the terminal is not synchronized, the controller 1y-30 may control to transmit the beam feedback information through a random access procedure. When the beam feedback is triggered, the random access preamble is transmitted, the random access response is received in response to the random access preamble transmission, the beam feedback information is transmitted based on the random access response reception, and the beam feedback information is transmitted in response to It can be controlled to receive a random access contention result. The message for transmitting the beam feedback information may be MSG3 in the random access procedure.

In addition, the control unit 1y-30 receives the beam change indication information, and upon receiving the beam change indication information, may control to change the beam based on the beam feedback information after a preset time.

1z is a diagram illustrating a base station according to an embodiment of the present invention.

Referring to FIG. 1z , the base station may include a transceiver 1z-10 and a control unit 1z-30 for transmitting and receiving signals. Through the transceiver 1z-10, the base station may transmit and/or receive signals, information, messages, and the like. The controller 1z-30 may control the overall operation of the base station. The controller 1z-30 may include at least one processor. The controller 1z-30 may control the operation of the base station described with reference to FIGS. 1A to 1X . The controller 1z-30 may include at least one processor.

Also, the controller 1z-30 may control to transmit a beam feedback trigger condition to the terminal and receive a medium access control (MAC) control element (CE) including beam feedback information from the terminal. The beam feedback information may be triggered when it is determined that the beam feedback condition is satisfied in the MAC layer of the terminal. That is, the beam feedback condition may be triggered according to the determination of the MAC layer of the terminal. The beam feedback trigger condition may include a case in which a channel measurement value of at least one beam is greater than a sum of a preset threshold value and a channel measurement value of a current serving beam.

In addition, if the uplink of the terminal is synchronized, the controller 1z-30 allocates an uplink resource to the terminal through a scheduling request (SR) procedure, and the beam feedback from the allocated uplink resource You can control to receive information.

Also, if the uplink of the terminal is not synchronized, the controller 1z-30 may control to receive the beam feedback information through a random access procedure. Receive a random access preamble from the terminal, transmit a random access response based on the random access preamble reception, receive the beam feedback information in response to the random access response transmission, and random access contention based on the beam feedback information reception You can control the sending of results. The message for receiving the beam feedback information may be MSG3 in the random access procedure.

In addition, the controller 1z-30 transmits beam change indication information based on the reception of the beam feedback information, and when transmitting the beam change indication information, controls to change the beam based on the beam feedback information after a preset time can do.

[Example B: Beam Grouping]

According to an embodiment of the present invention, in a beam management method between a terminal and a base station, the terminal transmits beam measurement information to the base station, the base station selects a beam to use based on the received beam measurement information of the terminal, the base station It is possible to provide a method comprising the steps of notifying the terminal of beam information to be used, and the steps of changing the beam currently being used by the base station and the terminal to a new beam.

In addition, according to an embodiment of the present invention, in the terminal, when the base station changes the beam to each beam in the step of transmitting the beam measurement information to the base station, a method including an indicator of whether it is necessary to transmit a beam change message And it is possible to provide a method of changing the beam of the base station using such an indicator.

The wireless communication system considers a structure in which one base station including a plurality of transmitting/receiving terminals capable of transmitting/receiving supports a wide physical area in order to improve the delay due to frequent terminal information exchange and to efficiently utilize resources.

Distributed Antenna System (DAS) that transmits or receives the same signal by simply implementing different transmitter/receiver terminals under one base station as a physical antenna;

A remote radio head (RRH) system capable of transmitting or receiving different signals by implementing different transmitter/receiver terminals under one base station in a structure including an antenna and a simple radio frequency (RF) terminal;

Different transmitters/receivers under one or different base stations synchronize the same information to one user at the same time to transmit/receive, or one transmitter/receiver transmits/receives information while the other transmitter/receiver is silent An example is a coordinated multi-point transmission/reception (CoMP) system.

Analog beamforming uses multiple array antennas to transmit different transmission powers and phases to superimpose the radiation patterns of the antennas to form beams that physically have directivity in a specific direction and obtain antenna gains.

In analog beamforming, the beam can be set in a desired direction without channel information of the desired target receiving end from multiple antennas, and only transmit/receive in one direction at a time (radiation patterns in other directions are canceled). When using multiple antennas With strong straightness, it can reach farther with the same power and form a beam with a large antenna gain (beam width/length difference according to the number of antennas)

Digital beamforming utilizes multi-channel information between antennas having different intensities in a multi-antenna transmission/reception environment, and applies different coding for each antenna to information before transmission to cancel desired inter-channel interference. It is a technique that forms

Digital beamforming uses pre-coding for data transmitted to each antenna to take full advantage of different channel characteristics.

Also, it is possible to support the same user multi-antenna (Single-user MIMO) and support multi-user multi-antenna (Multi-user MIMO).

Hybrid beamforming is a technology that uses analog beamforming and digital beamforming at the same time.

Hybrid beamforming is a technology that uses digital beamforming by using different pre-coding techniques for each antenna for beams and transmission antennas formed by analog beamforming.

The technique described in the embodiment of the present invention may be one of the techniques using the beam formed by the analog beamforming, the digital beamforming, and the hybrid beamforming and the beamforming. In addition, a method of occupying and transmitting any resource that can be physically or frequency/time/code/signal, etc. for information transmission is called beamforming, and it is applicable to all systems in which the occupied resource is called a beam.

In addition to this, the characteristics of the related technology used in the wireless communication technology conforming to the 3GPP standard are as follows.

* Uplink and uplink (uplink: transmission from a station to a base station) transmission should be transmitted using resources reserved through resource allocation of a base station (eNB, base station).

A terminal requiring uplink transmission transmits a resource allocation request (SR) allocated by the base station in advance to be allocated resources for uplink transmission (specifically, after SR transmission, the resource allocated by the base station (buffer status) report (BSR) to inform the amount of data to be transmitted in uplink, allocate resources and perform uplink transmission) A random access channel (RACH) that can be transmitted through contention-based contention with other terminals ) must be transmitted through

Channel measurement information feedback includes a technique for notifying the base station of channel information measured by the terminal, and there are channel measurement and feedback performed in the physical layer. Examples of such information include channel reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-noise ratio (SNR), signal-to-noise and interference. ratio (signal-to-interference-plus-noise ratio, SINR), channel quality quantization information (channel quality indicator, CQI), channel measurement reference signal measurement value (channel state inforamtion-reference signal, CSI-RS), etc. . Such information can be obtained by the UE by measuring any signal (cell specific reference signal or common reference signal (CRS), dedicated reference signal (DRS), CSI-RS, demodulation reference signal (DMRS)) transmitted by the base station.

The terminal may transmit the thus obtained information using the resource allocated by the base station according to the uplink transmission rule. If there is no resource allocated by the base station, there is no method or need to provide such information to the base station in a wireless communication technology.

In order to improve efficiency, the wireless communication system transmits signals for maintaining connectivity, such as control signals and reference signals, using a common receivable frequency channel and time resource so that all users can hear them.

On the other hand, in the case of a multi-antenna beamforming system that allocates and uses resources such as frequency channels, time, beams, and codes differently for different beams, beam characteristics (direction, direction, Channel, etc.) may cause a case where resource use is not possible due to change.

For example, in a system using a plurality of analog beams for transmission/reception, a terminal and a base station select a specific beam estimated to have good performance and transmit/receive information. In this case, the base station reserves the best (or least problematic) beam resource known at the time the base station reserves the resource for the resource advance reservation for uplink transmission of the terminal. However, a change may occur in the channel of the reserved beam resource due to the movement of the terminal or other variables (eg, an obstacle such as a sudden vehicle, climate change, etc.). When uplink information transmission fails due to a change in the characteristics of the reserved beam resource, there is no way to quickly solve the problem with the existing technology.

Therefore, in the case of a multi-antenna beamforming system that allocates and uses resources such as frequency channels, time, beams, and codes differently for different beams, it is possible to track and apply beam status information exchange between the terminal and the base station and rapid beam change. There is a need for a beam management technique.

In addition, in the case of the existing technology of transmitting signals for maintaining connectivity, such as control signals and reference signals, using a common receivable frequency channel and time resource so that all users can hear it, it is possible to overcome this when the used channel condition deteriorates. The only method is to change to another channel of the other frequency when another channel of a different frequency exists, or to reconnect to the network after declaring a failure when the radio link failure condition is satisfied. .

However, in the case of a multi-antenna beamforming system that allocates and uses resources such as frequency channels, time, beams, and codes differently for different beams, even if the characteristics of the beams being used deteriorate, other beams that can be used at the same location are not available. Since the probability of existence is high and the terminal is given an opportunity to maintain connectivity through this, a technology that can utilize it is required.

In the case of existing technologies (use of omni antenna, system using digital beamforming, etc.), if the status of the channel being used is bad, the method to overcome this is to change to another channel of a different frequency or to fail the radio link (radio link failure, If the RLF) condition is satisfied, the only way is to declare a failure and then try to reconnect to the network.

However, in a system using analog beamforming, even if the channel state of the beam being used deteriorates, there is a high probability that another beam that can be used at the same location exists, and the connection can be maintained through this.

In the prior art, a method for the UE to inform the base station of the resource being used in the base station, in particular, the channel state change is channel information feedback, which was only possible in the physical layer. In this prior art, the terminal receives a specific signal (CRS, DRS, RS, Beam RS, CSI-RS, etc.) transmitted by the base station to determine the channel state, and then processes and packs the channel state information into feedback information (e.g. : CQI, RI, PMI, etc.) and then transmit it to the base station using resources allocated by the base station for uplink transmission (eg, pshsical uplink control channel (PUCCH), physical uplink shared channel (PUSCH), etc.), or the terminal may transmit an uplink transmission request (or a resource allocation request for uplink transmission) to the base station, then receive resource allocation and transmit channel state information.

However, in the case of a multi-antenna beamforming system that allocates and uses resources such as frequency channels, time, beams, and codes differently for different beams, the unique resources used by the terminal/base station (eg, analog beam, hybrid beam) etc.), a new procedure is needed to inform the base station of other available resource information and to allocate and use the resource in the future.

2A is a diagram illustrating a multi-beam system according to an embodiment of the present disclosure.

Referring to FIG. 2A , the system consists of a base station and a terminal that form analog beams having various directions. Here, the analog beam used by the base station and the terminal may be composed of a plurality of small antenna arrays, and wireless transmission/reception may be performed in one direction by using one antenna array group at a time. In this case, when one or more simultaneously operable antenna array groups are included, wireless transmission/reception may be performed in one or more directions at a time.

In an embodiment of the present disclosure, one or more base stations (or transmitters/receivers) in a multi-antenna-using beamforming system that differently allocates and uses resources such as frequency channels, time, beams, and codes for different beams, a terminal An environment in which a pair of beams are transmitted/received using one or more beams at a time is basically considered. In addition, the base station or the terminal does not use a plurality of beams, for example, when the base station uses more than one beam and the terminal uses one beam, or when the base station uses one beam and the terminal uses more than one beam A possible beam information exchange method is proposed.

As a more detailed operation method, the terminal measures beam information, provides beam information, and exchanges and changes beam information in use within the same base station (or transmitter/receiver) through a procedure of changing the beam in use. At that time, a suitable beam is found and the corresponding beam can be used. In a multi-antenna beamforming system that allocates and uses resources such as frequency channels, time, beams, and codes differently for different beams, the base station and the terminal determine the channel state of the transmit/receive beam in real time, track it, and use it. Be able to maintain and change the beam.

Beam measurement is performed in order to measure channels of beam pairs that can be output by a combination of various beams between the terminal and the adjacent base station.

Beam measurement may be performed periodically or non-periodically, and may be performed by a terminal or a base station.

An embodiment of the present disclosure is not limited by any beam measurement method, and it can be assumed that the terminal or the base station can measure the channel state of beam pairs with each other.

In the embodiment of the present invention, it is assumed that the terminal continuously performs the operation of measuring the beam information in any way, and as a result of this, it is assumed that the environment is performing the operation of recognizing the measured value by updating the measured value according to each beam information measurement. can do.

Beam feedback is an act of notifying the base station of beam information measured by the terminal.

Since the base station (or terminal), which is the transmitting end, cannot know the downlink (or uplink) beam information, feedback from the terminal (or base station) is essential.

Beam information feedback may be performed periodically or non-periodically, and may be mutually performed by a terminal or a base station.

An embodiment of the present disclosure provides an operation of transmitting beam information measured by the terminal to the base station. However, the scope of the present disclosure is not limited to beam feedback or reporting of the terminal, and may be applied correspondingly to an operation of transmitting beam information measured by the base station to the terminal. Therefore, the procedure for beam feedback and beam change of the terminal below may be applied to the operation of the base station in the same/similar manner.

In an embodiment of the present invention, the beam feedback and beam feedback information may be beam state information (BSI) or beam refinement information (BRI).

In order to change the beam, the base station or the terminal may determine a beam pair to be used in the future based on the received beam feedback information.

The base station or the terminal may perform various operations to use the determined beam pair.

A terminal (UE, terminal) means a beam measurement entity that performs beam measurement, and a base station (eNB, base station) transmits a reference signal for beam measurement and allocates resources to the beam measurement entity. , when the beam measurement subject informs the beam information through the measurement through feedback, it means the beam user who uses it.

The terminal and the base station are used as a beam measurement and feedback performer and a beam reference signal transmission and resource allocation agent, but their roles are not limited to the terminal and the base station. The base station may be a subject that performs beam measurement and feedback, and the terminal may be a subject that transmits a beam reference signal or allocates resources.

The best beam (or best beams) is determined by determining one beam of the beam measuring subject and one of the beam using subjects, which are estimated to have the best performance among analog beams that can be used by the beam measuring subject and the beam using subject. , it may mean one beam pair (or beam pairs) composed of beams of these two subjects, or two beams in the beam pair (or beam pairs), respectively. In an embodiment of the present invention, the best beam is generally used by the beam using subject (base station) to communicate with the beam measuring subject (terminal) within the best beam pair measured according to the reference signal transmitted by the beam using subject (base station) It may be the beam with the best performance of the subject using the beam, but is not limited thereto.

The beam measuring entity may inform the beam using entity of information on the best beam pair (or beam pairs) through feedback, or may inform the corresponding beam measuring entity of only one beam information to be used by the beam measuring entity. (For example, the terminal may inform only one beam information belonging to the base station to be used when the base station transmits/receives information to the corresponding terminal)

2B is a diagram illustrating a frame structure for feeding back multiple beam IDs and beam measurement values according to an embodiment of the present disclosure.

Referring to FIG. 2B , an embodiment of a MAC-CE structure for transmitting N beam information (ID 9 bits, BRSRP 7 bits) can be confirmed.

BI (9-bit) is a field indicating a beam index.

BRSRP (7-bit): A field indicating RSRP of a beam.

Although FIG. 2B shows the BI as 9 bits and the BRSRP as 7 bits, each of the fields may have a different number of bits.

2C is a diagram illustrating a frame structure for feeding back multi-beam IDs and beam measurement values according to the present disclosure.

Referring to FIG. 2C , an embodiment of a MAC-CE structure for transmitting N beam information (eNB beam ID 3 bits, BRSRP 7 bits) can be confirmed.

RBI (3-bit) is a field indicating a beam index.

RB-RSRP (7-bit) is a field indicating the reception RSRP of the beam.

R is a reserved bit, set to "0".

Although the RBI is shown as 9 bits and the RB-RSRP as 7 bits in FIG. 2C, each field may have a different number of bits.

2D is a diagram illustrating a frame structure for feeding back multiple beam IDs and beam measurement values according to an embodiment of the present disclosure.

Referring to FIG. 2D , a MAC-CE structure for transmitting N beam information (eNB ID 9bit, UE ID 5bit, BRSRP 7bit) can be confirmed.

BI_1 (9-bit) is a field indicating the beam index of the base station.

BI_2 (9-bit) is a field indicating the beam index of the terminal.

BRSRP (7-bit) is a field indicating RSRP of a beam.

In one embodiment of the present disclosure, the following method is proposed in order to improve information exchange efficiency with the base station while minimizing information transmitted by the terminal to the base station.

An indicator addition method for requesting beam change information transmission is described below.

FIG. 2E is a diagram illustrating beam change through beam feedback, and FIGS. 2F and 2G are diagrams illustrating frame structures for transmitting beam feedback.

The terminal has a channel/link measurement value for a pair of a transmit beam of each base station and a receive beam of the terminal through the observed and measured information. Based on these channel measurement values, the UE feeds back measurement values and base station beam ID information for the top few or best several base station beams. In this way, when the terminal provides only information about the base station beam to the base station, when the base station that has received the corresponding information uses which beam, the terminal does not have information on which beam to receive. In other words, when the base station wants to change from the currently used beam to a new beam at the point in time when the corresponding beam feedback information is received, it notifies the terminal that it will try to change to the corresponding beam even when it wants to change to any beam, The UE and the UE must wait until a mutually agreed time to change the beam.

When the beam change request message is referred to as a Beam Change Indication message (BCI), an example of a corresponding operation procedure is shown in FIG. 2E .

As shown in FIG. 2E , when only the beam information of the base station is fed back without beam information of the terminal, a beam change request message is transmitted/received for every beam change, and the beam must be changed by waiting until an agreed time. However, if the beam of the base station needs to be changed, but the terminal does not need to change the beam even if the base station beam is changed, transmission of the beam change request message and the waiting time until the beam change is wasted. In fact, in the case of a system environment that considers multi-path and multiple transmission points (separated transmission reception points), the UE may receive multiple beams of the same cell using one Rx beam. At this time, if the beam measurement information fed back to the base station does not include the Rx beam information of the corresponding terminal, it becomes impossible to distinguish the case where there is no need to send a beam change request message (BCI) as described above, and the network After transmitting the BCI, a beam change is performed after a certain period of time.

In order to eliminate the above waste, this patent proposes a method of transmitting beam feedback by adding an indicator of one bit to the beam information of the base station as shown in FIGS. 2F and 2G.

2F and 2G show examples of a method of transmitting by adding an indicator of 1 bit to one base station beam feedback according to an embodiment of the present disclosure.

The indicator may provide terminal beam information to the base station, and may be used in the following way.

When the base station changes the used beam to the corresponding beam, the indicator is set as an indicator to inform the terminal that a beam change request message should be transmitted.

The UE may manage the measured beam pair information in the following table:

[Table 17] is a beam pair measurement information management table of the terminal.

[Table 17]

The UE arranges the beam pairs having the best performance (best quality, best RSRP, RSRQ, CQI, SNR, SINR, ...) in the beam pair measurement information in descending order to generate beam feedback information to be transmitted to the network. :

[Table 18] is an example of beam pair measurement information feedback of K terminals.

[Table 18]

If the UE Rx beam ID in the beam measurement information feedback table is the same as the currently used serving beam ID (the last beam ID), the indicator is 0, otherwise, the indicator is 1.

Alternatively, the same indicator may be allocated when the UE Rx beam IDs in the beam measurement information feedback table are Rx beams that can be simultaneously received by the UE, and different indicators may be allocated to Rx beams that cannot be simultaneously received.

[Table 19] is an example of including indicators in the beam pair measurement information feedback of the K terminals when the serving beam ID currently being used by the terminal is 1.

*[Table 19]

If the UE Rx beam ID is removed from the information, the beam feedback information is completed.

[Table 20] is an example of the beam pair measurement information feedback of the K terminals when the serving beam ID currently being used by the terminal is 1.

[Table 20]

2H is a diagram for explaining operations of a base station and a terminal for changing from a currently used base station beam to an (on, 1) base station beam with a corresponding indicator turned on according to an embodiment of the present disclosure.

In this case, the corresponding indicator (1) is an indicator indicating that, in the case of a beam on which the corresponding indicator is turned on, communication is possible only when a terminal beam different from the terminal beam currently used by the terminal is used.

At this time, when changing the beam from the currently used base station beam to the (0) base station beam whose corresponding indicator is turned off, the base station may arbitrarily change the beam without providing any information to the terminal. If the base station arbitrarily changes the beam without providing any information in this way, time consumption such as waiting for BCI transmission and beam change to the terminal is reduced, enabling efficient and fast beam change.

In various embodiments of the present disclosure, it is possible to apply 0 and 1 as the values of the indicator opposite to those described above, and the indicator is not limited to 1-bit information.

In addition, if the indicator has the same value, it may indicate the base station beams that the terminal can receive simultaneously. In this case, this may indicate that the terminal can simultaneously receive the base station beams indicated by the corresponding indicator using the same rx beam (or available simultaneous receivable rx beams). In this case, the base station may transmit to the terminal by simultaneously utilizing two or more base station beams indicated by the corresponding indicator.

FIG. 2H is a diagram illustrating operations of a base station and a terminal for changing a base station beam being used to a base station beam having an indicator set to on according to an embodiment of the present disclosure.

Referring to FIG. 2H, in operation 2h-05, the UE may transmit a beam measurement report to the base station. The terminal may generate beam measurement report information by measuring the channel quality between the reception beam of the terminal and the transmission beam of the base station. The beam measurement report may include the information described in Tables 17 to 20. In addition, the beam measurement report information may include a transmission beam ID of the base station, Beam RSRP (or RSRQ, CQI, SNR, SINR, etc.), and an indicator.

In operation 2h-10, the base station may determine to change the beam currently being used for the terminal. The base station may determine whether to change the beam based on the beam measurement report received from the terminal.

In operation 2h-15, the base station may check the indicator included in the beam measurement report information. The base station may determine whether it is necessary to transmit the BCI message or to wait for a preset time when changing the beam based on the indicator. For example, it may be checked whether the indicator for the beam to be changed is 1. When the indicator is 0, the 2h-20 operation may be performed, and if the indicator is 1, the 2h-25 operation may be performed. The base station may recognize beam pairs having an indicator of 0 as one group, and may recognize beam pairs having an indicator of 1 as a group.

When the indicator is 0, in operation 2h-20, the base station may change the beam without transmitting the BCI message to the terminal. Indicator 0 may indicate a transmit beam of a base station that is currently receivable as a receive beam of the terminal.

When the indicator is 1, the base station may transmit a BCI message to the terminal in operation 2h-25. The BCI message may include identification information (eg, Beam ID) on a beam to be changed by the base station. Indicator 1 may indicate a transmission beam of a base station that is not currently receivable as a reception beam of the terminal. In this case, when the base station changes to the corresponding transmit beam, the terminal needs to change the receive beam.

In operation 2h-30, the base station may use a new beam after waiting for a preset time (or preset TTI, subframe) after transmitting the BCI message. In operation 2h-35, the UE may use a new beam after waiting for a preset time (or a preset TTI, subframe) after receiving the BCI message. The base station may use the changed transmit beam, and the terminal may use the changed receive beam.

The base station transmits downlink information using the changed transmit beam, and the terminal may receive the downlink information transmitted by the base station using the current receive beam when the changed receive beam or the receive beam change of the terminal is unnecessary.

When the indicator is changed to a beam other than 1, BCI transmission/success and waiting time can be omitted, thereby reducing latency.

In addition, the indicator may indicate the base station beams that the terminal can simultaneously receive. In this case, this may indicate that the terminal can simultaneously receive the base station beams indicated by the corresponding indicator using the same rx beam (or rx beams). In this case, the base station may transmit to the terminal by simultaneously utilizing two or more base station beams indicated by the corresponding indicator.

When the base station changes the beam used by the corresponding beam, an indicator is provided indicating that the change is possible at any time without a special message.

FIG. 2i is a diagram for explaining operations of a base station and a terminal when the indicator is an indicator indicating that the base station can freely change the BCI without sending the BCI to the terminal according to an embodiment of the present disclosure.

Contrary to FIG. 2H, in FIG. 2I, the Indicator may be an indicator indicating that the base station can freely change without sending a BCI message to the terminal.

The base station transmission beams of which the indicator is 0 may be simultaneously used by the determination of the base station and used for MIMO transmission to the terminal.

Referring to FIG. 2I , in operation 2i-05, the terminal may transmit beam measurement reporting information to the base station. The terminal may generate a beam measurement report by measuring the channel quality between the reception beam of the terminal and the transmission beam of the base station. The beam measurement report may include the information described in Tables 17 to 20. In addition, the beam measurement report is not limited thereto, and may include one of beam pair measurement information feedback of the present invention. For example, it may include the transmission beam ID of the base station, Beam RSRP (or RSRQ, CQI, SNR, SINR, etc.), and an indicator. The indicator may be an indicator indicating that the base station can freely change without sending the BCI to the terminal.

In operation 2i-10, the base station may determine to change the beam currently being used for the terminal. The base station may determine whether to change the beam based on the beam measurement report received from the terminal.

In operation 2i-15, the base station may check the indicator included in the beam measurement report. The base station may determine whether it is necessary to transmit the BCI message or to wait for a preset time when changing the beam based on the indicator. For example, it may be checked whether the indicator for the beam to be changed is 1. If the indicator is 0, operation 2i-20 may be performed, and if the indicator is 1, operation 2i-25 may be performed. The base station may recognize beam pairs having an indicator of 0 as one group, and may recognize beam pairs having an indicator of 1 as a group.

When the indicator is 0, in operation 2i-20, the base station may change the beam without transmitting the BCI to the terminal. Indicator 0 may indicate a transmit beam of a base station that is currently receivable as a receive beam of the terminal.

When the indicator is 1, the base station may transmit BCI to the terminal in operation 2i-25. The BCI message may include identification information (eg, Beam ID) on a beam to be changed by the base station. Indicator 1 may indicate a transmission beam of a base station that is not currently receivable as a reception beam of the terminal. In this case, when the base station changes to the corresponding transmit beam, the terminal needs to change the receive beam.

In operation 2i-30, the base station may use a new beam after waiting for a preset time (or preset TTI, subframe) after transmitting the BCI message. In operation 2i-35, the UE may use a new beam after waiting for a preset time (or a preset TTI, subframe) after receiving the BCI. The base station may use the changed transmit beam, and the terminal may use the changed receive beam.

The base station transmits downlink information using the changed transmit beam, and the terminal may receive the downlink information transmitted by the base station using the current receive beam when the changed receive beam or the receive beam change of the terminal is unnecessary.

An indicator indicating that the terminal can simultaneously receive even if the base station uses the corresponding beams as the transmit beam at the same time

* When the indicator indicates that the terminal can receive simultaneously: This may indicate that the terminal can simultaneously receive the base station beams indicated by the corresponding indicator using the same rx beam (or rx beams). In this case, the base station may perform simultaneous transmission to the terminal by using two or more base station beams indicated by the corresponding indicator at the same time.

In addition, the indicator does not necessarily have to be 1 bit, and the indicator of the same value may indicate a plurality of beams that can be transmitted simultaneously.

In addition, the indicator may be used as any arbitrary beam group ID set by the terminal, and in this case, the base station recognizes that the terminal has divided the base station beam into groups, distinguishes different groups, and performs a specific operation (eg, beam measurement and reporting) ) can also be indicated.

When the UE can operate one Rx beam at a time, and it is possible to simultaneously receive beam transmissions from different base stations using the one Rx beam, the method of writing feedback information including the beam indication of the UE is as follows.

[Table 21] is a table for managing beam pair measurement information of the terminal.

[Table 21]

The UE arranges the beam pairs having the best performance (best quality, best RSRP, RSRQ, CQI, SNR, SINR, ...) in the beam pair measurement information in descending order to generate beam feedback information to be transmitted to the network. :

[Table 22] is an example of beam pair measurement information feedback of K terminals.

[Table 22]

Table 22 is a table listing measurement information bundled with a base station Tx beam and a terminal Rx beam pair in order of good performance. For example, in the example of Table 22 here, the channel performance (RSRP) of the Tx beam of the base station 2 and the Rx beam of the terminal 1 was the best, and the channel performance (RSRP) of the Tx beam of the base station No. 4 and the Rx beam of the terminal 4 Next, it means good.

In this way, the UE, after completing the ordering according to the received signal strength of the beam pairs, may group the beam pairs capable of being simultaneously received by the same indicator with the same indicator (groping) and allocate the indicator.

[Table 23a] Table for allocating indicators by grouping beams that can be simultaneously received by the UE in order of performance

[Table 23a]

In [Table 23a], the UE allocates groups in the same order of its Rx beam ID, distinguishes base station-terminal beam pairs belonging to the group, and allocates them with the same indicator.

In Table 23a, the UE allocates the indicator of the group to which the best base station-terminal beam pair belongs to 0, and after confirming that the next best base station-terminal beam pair does not belong to indicator 0, a new group indicator is assigned to 1. In the case of the third best base station-terminal beam pair, 1, which is the same group indicator as the second best base station-terminal beam pair, was assigned because it has the same rx beam as the second best base station-terminal beam pair and can be simultaneously received. . With this rule, the terminal may proceed by grouping information of base station terminal beam pairs to be fed back (transmitted) to the network by the terminal sequentially.

Here, it is appropriate to remove the terminal rx beam id column and transmit information that the terminal actually feeds back to the base station. Of course, a method of including and transmitting the corresponding terminal rx beam id may also be considered.

[Table 23b] Table for allocating indicators by grouping beams that can be simultaneously received by the terminal in the order of the terminal reception beam

[Table 23b]

In [Table 23b], the UE allocates groups in the same order of its Rx beam ID, distinguishes base station-terminal beam pairs belonging to the group, and allocates them with the same indicator.

In [Table 23b], the UE allocated the group indicator of each beam pair by using its Rx beam ID. For example, in the case of a base station-terminal beam pair having a terminal Rx beam ID of 4, indicator is also a method of allocating to 4. A disadvantage of this method is that the number of bits for indicator transmission must be guaranteed as much as the number of rx beams of the terminal regardless of the amount of beam information transmitted by the terminal in feedback. For example, assuming that a certain terminal has 12 rx beams and sends only 4 beam measurement information each time, 4 bits must be guaranteed so that the maximum number of bits in the signal for the indicator can be 12.

Here, it is appropriate to remove the terminal rx beam id column and transmit information that the terminal actually feeds back to the base station. Of course, a method of including and transmitting the corresponding terminal rx beam id may also be considered.

*

[Table 23c] A table for configuring feedback transmission by bundling the same number of beams that can be simultaneously received by the UE for each group

[Table 23c]

In [Table 23c], the UE allocates the group indicator to the beam pairs having the same Rx beam ID in the performance order in the same way as in [Table 23a], and then includes information on the same number of beam pairs in all the groups. was reconstructed.

In [Table 23a], the group indicator of the terminal was allocated in the order of performance, but here [Table 23c], after allocating the group indicator as in [Table 23a] (or using [Table 23b] or any method, the group indicator After allocating ), this is an example of rearranging the number of beam pairs that belong to the corresponding group and are fed back to the base station to be equal to two.

In this way, when the same number of beam information for each group is included and provided to the network, the network may include the number of beam pairs to be transmitted by the terminal for each group in the downlink signal and deliver it to the terminal.

For example, as in the example of Table [23c], a base station that wants to receive information on two beam pairs for each group may transmit the number of beam pairs per group to the terminal using one of the following methods.

In the RRM measurement report configuration signal, the total number of beam pairs to be reported, the number of beam pairs to be reported per group, and the number of groups to be reported may be included and transmitted. In this case, the UE includes a group and the number of beam pairs to be reported per group in the RRM measurement report for uplink transmission according to a condition. For example, when the total number of beam pairs to report is K, the number of beam pairs to report per group is L, and the number of groups to report is M, the UE can report in the following way.

When K > L x M, the UE provides L x M beam pair information to the network by L for M groups.

When K < L x M, the UE lists the beam pairs in the order in which the performance of each beam pair is good, and each group includes a maximum of L beams within the limit of not exceeding the maximum M beam groups for a total beam pair Report signals are configured so that the number becomes K, and information is provided to the network.

When L=0, M=0, or L=∞, M=∞, the UE does not care about the number of beams per beam group, and as shown in [Table 23a] and [Table 23b], K Information is provided to the network by composing a report signal as much as possible.

The beam measurement information provided by the terminal may include information such as base station transmission beam id, terminal reception beam id, beam measurement quantity (RSRP, RSRQ, SNR, SINR, CQI, ...), group indicator, and the like.

In the downlink physical layer control signal (DCI on PDCCH) or MAC-CE signal, the total number of beam pairs to be reported, the number of beam pairs to be reported per group, and the number of groups to be reported may be included and transmitted. In this case, the UE includes an uplink control signal (UCI on PUCCH), an uplink data signal (Data on PUSCH), or an uplink MAC-CE transmitted through uplink according to a condition, including the number of beam pairs to be reported per group and per group send. For example, when the total number of beam pairs to report is K, the number of beam pairs to report per group is L, and the number of groups to report is M, the UE can report in the following way.

When K > L x M, the UE provides L x M beam pair information to the network by L for M groups.

When K < L x M, the UE lists the beam pairs in the order in which the performance of each beam pair is good, and each group includes a maximum of L beams within the limit of not exceeding the maximum M beam groups for a total beam pair Report signals are configured so that the number becomes K, and information is provided to the network.

When L=0, M=0, or L=∞, M=∞, the UE does not care about the number of beams per beam group, and as shown in [Table 23a] and [Table 23b], K Information is provided to the network by composing a report signal as much as possible.

The beam measurement information provided by the terminal may include information such as base station transmission beam id, terminal reception beam id, beam measurement quantity (RSRP, RSRQ, SNR, SINR, CQI, ...), group indicator, and the like.

On the other hand, it is appropriate to remove the terminal rx beam id column and transmit the information that the terminal actually feeds back to the base station. Of course, a method of including and transmitting the corresponding terminal rx beam id may also be considered.

A method of adding an indicator for requesting beam change information transmission of a terminal capable of simultaneously using multiple Rx beams will be described below.

The terminal has a channel/link measurement value for a pair of a transmit beam of each base station and a receive beam of the terminal through the observed and measured information as described above.

As described above, based on these channel measurement values, the terminal may feed back measurement values for the top few or best several base station beams and base station beam ID information by adding an indicator.

As such, in a method of providing beam feedback information with an indicator added to the base station, when the terminal can operate two or more different reception beams at the same time, the indicator and beam feedback information can be configured in the following way.

A. When the terminal needs to change to a reception beam other than the two or more reception beams currently being used for wireless communication, the indicator is displayed as ON (= 1, true) to transmit beam feedback

For the transmission beam of the base station that can be received using the beam being used by the terminal, an indicator is displayed as 0 and transmitted. For other beams, an indicator is displayed as 1 and transmitted.

[Table 24] When the UE rx beam IDs currently used by the UE are 1 and 2, this is a table including indicators in the beam pair measurement information feedback of the K UEs.

[Table 24]

If the UE Rx beam ID is removed from the information, the beam feedback information is completed as follows.

*

[Table 25] When the UE rx beam IDs 1 and 2 currently used by the UE are 1 and 2, this is a table including the Indicator in the completed beam feedback.

[Table 25]

In order to change from the currently used base station beam to the base station beam with the corresponding indicator turned on (1), the base station must change the beam through a procedure such as transmitting a BCI message to the terminal.

In this case, the corresponding indicator is an indicator indicating that, in the case of a beam on which the corresponding indicator is turned on, communication is possible only when a terminal beam different from the terminal beam currently used by the terminal is used.

At this time, when changing from the currently used base station beam to the (off, 0) base station beam for which the corresponding indicator is turned off, the base station may arbitrarily change it without providing special information to the terminal in advance. When the base station arbitrarily changes the beam without such a special procedure, time wasted such as waiting for a BCI message transmission and beam change to the terminal is reduced, enabling efficient and fast beam change.

In addition, the indicator may indicate the base station beams that the terminal can simultaneously receive. In this case, this may indicate that the terminal can simultaneously receive the base station beams indicated by the corresponding indicator using the same rx beam (or rx beams). In this case, the base station may transmit to the terminal by simultaneously utilizing two or more base station beams indicated by the corresponding indicator.

On the other hand, it is appropriate to remove the terminal rx beam id column and transmit the information that the terminal actually feeds back to the base station. Of course, a method of including and transmitting the corresponding terminal rx beam id may also be considered.

A beam change/beam simultaneous use method using an indicator of a base station is provided.

The base station (eNB, gNB, TRP, etc.) may select and change a beam to be used for communication with the terminal through the information received as described above. At this time, if the indicator intends to use a beam indicated to require transmission of a beam change request message (BCI) for beam change, the beam is used after transmission of the corresponding beam change request message and beam change procedure. shall.

On the other hand, if the indicator indicates that the UE can receive using the same rx beam, and thus wants to use a beam that does not require transmission of a BCI message for beam change, transmission of the corresponding beam change request message and beam change procedure are not performed. You are free to use that beam.

In addition, the indicator may indicate the base station beams that the terminal can simultaneously receive. In this case, this may indicate that the terminal can simultaneously receive the base station beams indicated by the corresponding indicator using the same rx beam (or rx beams). In this case, the base station may transmit to the terminal by simultaneously utilizing two or more base station beams indicated by the corresponding indicator.

Conversely, a method of using as an indicator indicating a case in which simultaneous reception is impossible will be described below.

The indicator may indicate the base station beams that the terminal cannot receive at the same time. In this case, this may indicate that the UE cannot receive the base station beams indicated by the corresponding indicator using the same rx beam (or rx beams) at the same time. The base station may transmit to the terminal by simultaneously utilizing two or more base station beams included in different indicator groups.

Alternatively, when the UE can use multiple Rx beams at the same time, in order to obtain a diversity gain using these different rx beams, the base station beams that cannot be simultaneously received are based on the same rx beam, or the diversity gain is maximized. It can also be grouped and indicated in a direction that makes it possible.

For example, referring to Table 23a, the UE indicates to the network by grouping transmission beams of the network that can be received using the same rx beam. In this case, if the terminal is capable of receiving different rx beams at the same time, the beams that can be transmitted simultaneously using this information must be selected from among the base station beams belonging to different group indications, not within the same group indication, and the terminals are each other It is possible to simultaneously receive these base station beams using other rx beams.

A method of transmitting the first beam feedback according to selection of a beam to be used during initial access will be described below.

FIG. 2J is a diagram for explaining operations of a base station and a terminal in a first beam feedback transmission method according to selection of a beam to be used during initial access according to an embodiment of the present disclosure.

Referring to FIG. 2J , in order for the UE to select an indicator to be included in the beam feedback, it is necessary to be aware of the currently used rx beam. To this end, a method of selecting the first rx beam when the UE first accesses the network is proposed, and based on this, an indicator in the beam feedback to be transmitted in the future is selected.

When the terminal and the base station specify an usable beam using a method other than beam feedback,

When the UE selects the beam pair with the highest success rate through the pre-beam measurement result and performs random access using the beam pair and succeeds

When the UE performs random access in any way and successfully receives the RAR from the base station using a specific beam

When the terminal successfully receives a UE-specific message from the base station in any way

When the terminal and the base station specify an usable beam using beam feedback,

The UE transmits all indicators in the beam feedback transmitted before the beam is specified, indicating that a beam change message is necessary (eg, 1).

A transmission scheme including beam group information in the beam change indication of the base station will be described below.

When the terminal configures and transmits beam information to the base station as a group, the base station may select the following methods when transmitting a beam change indication for use of a new beam in downlink to the corresponding terminal.

How to transmit the beam ID to be changed and the beam group ID to which the beam to be changed belongs

The network may transmit the beam ID to be changed and the beam group ID together to the terminal. For example, if the beam group ID is an ID indicating a bundle of beams that can be simultaneously received by the terminal, if the base station transmits such a beam group ID, the terminal knows the beam group ID so that the base station uses any reception beam. It is possible to determine whether the transmission can be received. In a multi-antenna transmission/reception structure that may occur when one base station beam can be received as two or more terminal beams, if the same base station beam may belong to two or more different terminal beam groups, such beam division is There is an advantage of simplifying the operation of the terminal by giving the terminal a clear message that it can be received using any beam group. On the other hand, the base station has an overhead of performing an additional operation of classifying and selecting such a terminal group. Considering a terminal operating on a battery, there may also be an advantage in that the terminal's battery usage time can be extended by performing such an operation by the network and not by the terminal.

The network may transmit only the beam group ID without transmitting the beam ID to be changed to the terminal. For example, if the beam group ID is an ID indicating a bundle of beams that can be simultaneously received by the terminal, if the base station transmits such a beam group ID, the terminal knows the beam group ID so that the base station uses any reception beam. It is possible to determine whether the transmission can be received. The terminal only needs to be able to successfully receive information from the base station and transmit its own information, so only the terminal beam needs to be given information to properly select. This method has the advantage of simplifying the operation of the terminal by giving the terminal a clear message that it can be received using any beam group. Also, there is an advantage that the base station can use overlapping or changing beams within a corresponding group at any time desired by the base station.

Upon receiving the beam group ID, the terminal performs subsequent communication using a terminal Rx beam (or Rx beams) capable of receiving base station information transmitted with the corresponding beam group ID. Of course, this operation may be the same as the beam change operation of FIG. 2E, and the signal including the beam group ID may be transmitted instead of the beam ID in downlink information transmitted only for beam change.

According to an embodiment of the present disclosure, the UE may measure a beam or performance degradation of beams being used and trigger a beam recovery procedure for recovering to another beam by using the measurement. At this time, the procedure for determining the performance degradation of the beam being used is called the Beam Failure Detection procedure, and the conditions for triggering the beam recovery procedure including the beam failure detection procedure are possible in the following way.

According to the Beam Failure Detection method, the beam may be any beam (base station beam, terminal beam, or a pair of base station beam and terminal beam) that the terminal and the base station are using, or the terminal and the base station explicitly (or implicitly) It may be any set of beams being used.

Here, the beam may be a physical antenna configuration or may be a measurement unit of any UE (eg, SS block, SS burst, SS burst set, CSI-RS block, CSI-RS burst, CSI-RS burst set).

Resource / RS Configuration is achieved by beam recovery transmission resource allocation (i.e., RACH time / frequency / sequence, or any dedicated / common resource).

The beam (or beams) information (beam ID, RS location, frequency, time, etc.) with which the UE compares Condition 1 may be a threshold value, an offset value, etc. required by the UE.

L1 detection may be performed.

If the beam(s) measured by the physical layer satisfies Condition 1, beam failure is determined.

The physical layer transmits a corresponding indication to the upper layer for later operation.

The upper layer starts the beam recovery procedure after receiving the indication.

L2 detection with L1 indication may be performed.

If the beam(s) measured by the physical layer satisfies Condition 1, the corresponding indication is transmitted to the upper layer.

The L2 layer receives one or more indications from the physical layer, and when the reception of the indications satisfies Condition 2, the L2 layer determines beam failure and/or beam recovery triggering.

The L2 layer starts the beam recovery procedure.

L3 detection with L1 indication may be performed.

If the beam(s) measured by the physical layer satisfies Condition 1, the corresponding indication is transmitted to the upper layer.

When the L3 layer receives one or more indications from the physical layer and the reception of the corresponding indications meets Condition 2, it determines beam failure and/or beam recovery triggering.

The L3 layer starts the beam recovery procedure.

L2 detection with L1 indication may be performed.

If the beam(s) measured by the physical layer satisfies Condition 1, the corresponding indication is transmitted to the upper layer.

The terminal receives one or more indications from the physical layer and when the reception of the corresponding indications satisfies Condition 2, UL beam feedback transmission attempts (L1 feedback and/or L2 feedback) may be made using previously allocated resources.

The L2 layer determines beam failure and/or beam recovery triggering when any Condition 3 is satisfied.

The L2 layer starts the beam recovery procedure.

*

L3 detection with L1 indication may be performed.

If the beam(s) measured by the physical layer satisfies Condition 1, the corresponding indication is transmitted to the upper layer.

The UE receives one or more indications from the physical layer and attempts to transmit UL beam feedback using previously allocated resources if the reception of the indications satisfies Condition 2 (L1 feedback and/or L2 feedback and/or L3 reporting) )do.

The L3 layer determines beam failure and/or beam recovery triggering when any Condition 3 is satisfied.

The L3 layer starts the beam recovery procedure.

The Condition 1 may be a measurement value of beam(s) including a base station control channel measurable by the terminal < Threshold1.

The Condition 1 may be an estimated DL signal reception error probability>N1%.

The Condition 1 may be a beam(s) measurement value < Threshold1 (AND) any one beam measurement value > Threshold 2.

The Condition 1 may be any set1 of beams measurement value < Threshold1 agreed with the base station in advance (or configured from the base station).

The Condition 1 may be any condition created by a combination of the above conditions.

The Condition 2 may be the same or consecutive N2 indication reception (i.e., L1 OOS) as the condition1.

The Condition 2 may be the reception of indications (i.e., L1 OOS) of N3 or more times within a predetermined time (timer2).

The Condition 2 may be any one beam measurement value > Threshold 2.

The Condition 2 may be a measurement value of any beam in any set2 of beams previously agreed with the base station (or configured from the base station) > Threshold2.

If any timer1 triggered immediately after condition1 is satisfied, expires

: The timer1 may be a value set by the terminal implementation

: When IS is not received from L1 within the timer1

: When UL signal transmission is not successful within the timer1

: When condition1 condition is maintained within timer1

: The timer1 may be a value configured by the base station

*: The timer1 may be canceled when receiving any indication (i.e., In-sync-indicaiton) from the lower layer.

: The timer1 may be canceled when receiving any indication (i.e., RLF triggering indication, RLF declaration indication) from the upper layer.

- any condition created by the combination of the above conditions;

The Condition 3 may be consecutive N4 indication reception (i.e., L1 OOS) or more than N5 indication reception (i.e., L1 OOS) within a predetermined time (timer2).

The Condition 3 may be any one beam measurement value > Threshold3.

The Condition 3 may be a measurement value of any beam in any set2 of beams agreed upon with the base station in advance (or configured by the base station) > Threshold3.

If any timer2 triggered immediately after condition2 is satisfied, expires

: The timer2 may be a value set by UE implementation

: The timer2 may be a value configured by the base station

: When IS is not received from L1 within timer2

: When UL signal transmission is not successful within the timer2

: When condition1 and/or condition2 condition is maintained in timer2

: The timer2 may be a value configured by the base station

: The timer2 is a time value greater than a certain Threshold4, and may be a timer indicating the location of an uplink transmittable resource (PRACH, SR resource, etc.) that will arrive within the nearest time after the threshold4 or more has elapsed.

: The timer2 may be canceled when receiving any indication (i.e., In-sync-indicaiton) from the lower layer.

: The timer2 may be canceled when receiving any indication (i.e., RLF triggering indication, RLF declaration indication) from the upper layer.

- any condition created by the combination of the above conditions;

The Beam Recovery Request signal Transmission method is described below.

The UE may perform a beam recovery operation when the beam failure condition is satisfied. Specifically, the UE may transmit an uplink beam recovery request signal for beam recovery.

For this, the UE may immediately trigger a UL beam recovery request signal when beam failure condition 2 is satisfied.

FIG. 2K illustrates a method in which a UE attempts to transmit a beam recovery request when a certain condition2 condition is satisfied according to an embodiment of the present disclosure in association with an RLF operation.

Referring to FIG. 2K , when the condition (Condition2) is satisfied, the UE immediately triggers transmission of an uplink beam recovery request signal that will arrive within the nearest time. At this time, if the difference between the resource for performing the corresponding uplink transmission and the triggering time is large, it waits for the corresponding time and continuously determines whether the corresponding triggering condition is satisfied or not.

Also, between the trigger time and the actual transmission time, the terminal continuously transmits the UL signal using the previously allocated uplink resource. At this time, even if the measured value of the corresponding resource is less than a certain threshold (condition1), uplink transmission (beam resumption: uplink feedback using a pre-allocated resource) may be attempted to increase the success rate.

If the triggering uplink beam recovery request signal (BRR) transmission time has not arrived, and the corresponding triggering condition (Condition 1) is resolved (if it is no longer satisfied), the UE may cancel all ongoing procedures. For example, even if the uplink BRR signal transmission is triggered because the received signal strength of a certain beam is less than a certain threshold, if it is again observed that the received signal strength of the corresponding beam is above the corresponding threshold before the transmission time arrives, the triggered Uplink BRR signal transmission can be canceled.

The UE may trigger a UL beam recovery request signal after condition 3 is satisfied after the beam failure condition is satisfied.

FIG. 2L illustrates a method in which a UE attempts to transmit a beam recovery request when a certain condition2 condition is satisfied according to an embodiment of the present disclosure in association with an RLF operation. FIG. 2L is an example of waiting for a time until the PRACH arrives when the fixed timer ends.

Referring to FIG. 2L, when the condition (condition2) is satisfied, the UE sets which condition3 (eg, timer), waits for the corresponding condition to be satisfied, and continuously transmits the UL signal using the pre-allocated uplink resource. At this time, even if the measured value of the corresponding resource is less than a certain threshold (condition1), uplink transmission may be attempted to increase the success rate.

When Condition 3 is satisfied, the UE immediately triggers transmission of an uplink beam recovery request signal that will arrive within the nearest time.

At this time, if there is a difference between the time when the corresponding condition3 is satisfied and the resource for performing the UL beam recovery request transmission, it waits for the corresponding time and continues to perform the operation when the condition2 is satisfied (beam resumption: increase the use of pre-allocated resources) link feedback) and it may be determined whether the condition1 is not resolved.

If Condition3 is not satisfied, and the triggering condition (Condition1) is resolved (if it is no longer satisfied), the UE may cancel all ongoing procedures. For example, even if the uplink BRR signal transmission is triggered because the received signal strength of a certain beam is less than a certain threshold, if it is again observed that the received signal strength of the corresponding beam is above the corresponding threshold before the transmission time arrives, the triggered Uplink BRR signal transmission can be canceled. If the resource time point for performing the UL beam recovery request transmission has not arrived, and the corresponding triggering condition (Condition 1) is resolved (if it is no longer satisfied), the UE may cancel all ongoing procedures. For example, even if the uplink BRR signal transmission is triggered because the received signal strength of a certain beam is less than a certain threshold, if it is again observed that the received signal strength of the corresponding beam is above the corresponding threshold before the transmission time arrives, the triggered Uplink BRR signal transmission can be canceled.

In addition, if Radio Link Failure (RLF) is performed first when Condition 3 is not satisfied, or if Condition 3 is satisfied but Radio Link Failure is declared before reaching the nearest PRACH, the terminal cancels all beam recovery operations in progress. and can perform operations according to RLF.

FIG. 2M illustrates a method in which a UE attempts to transmit a beam recovery request when a certain condition2 condition is satisfied according to an embodiment of the present disclosure in association with an RLF operation.

Referring to FIG. 2M, the UE declares BRT by Condition1 or Condition2, and until a certain condition3 is satisfied (i.e., fixed timer expiration) Beam resumption operation (i.e., uplink feedback using a pre-allocated resource) is performed while performing An example of performing beam resumption operation (i.e., uplink feedback using previously allocated resources) while attempting beam recovery using PRACH when Condition 3 is satisfied (i.e., Timer expire) is shown. At this time, beam recovery using PRACH may be continuously performed when the corresponding condition 1 is satisfied, may be attempted only during the corresponding timer with a certain timer_br, or may be attempted until consecutive (or discontinuous) N_max_br failures are made. have.

FIG. 2N illustrates a method in which a UE attempts to transmit a beam recovery request when a certain condition2 condition is satisfied according to an embodiment of the present disclosure in association with an RLF operation.

Referring to FIG. 2N, the UE declares BRT by Condition 1 or Condition 2, and attempts beam recovery using PRACH while simultaneously performing beam resumption operation (i.e., uplink feedback using previously allocated resources). It shows an example. At this time, beam recovery using PRACH may be continuously performed when the corresponding condition 1 is satisfied, may be attempted only during the corresponding timer with a certain timer_br, or may be attempted until consecutive (or discontinuous) N_max_br failures are made. have.

FIG. 2o illustrates a method in which a UE attempts to transmit a beam recovery request when a certain condition2 condition is satisfied according to an embodiment of the present disclosure in association with an RLF operation.

Referring to FIG. 2O , the UE sets any condition3 (eg, timer), waits for a corresponding condition to be satisfied, and continuously transmits a UL signal using a pre-allocated uplink resource (beam resumption). At this time, even if the measured value of the corresponding resource is less than a certain threshold (condition1), uplink transmission may be attempted to increase the success rate.

Even if the fixed timer is over, the UE may continue to perform the beam resumption operation until the PRACH arrives or the Radio Link Failure is declared. When Condition 3 is satisfied, the UE immediately triggers transmission of an uplink beam recovery request signal that will arrive within the nearest time.

In addition, if Radio Link Failure (RLF) is performed first when Condition 3 is not satisfied, or if Condition 3 is satisfied but Radio Link Failure is declared before reaching the nearest PRACH, the terminal cancels all beam recovery operations in progress. and can perform operations according to RLF.

FIG. 2P illustrates a method in which a UE attempts to transmit a beam recovery request when a certain condition2 condition is satisfied according to an embodiment of the present disclosure in association with an RLF operation.

Referring to FIG. 2P, when the T310 timer for RLF is triggered, the UE may trigger a beam recovery request at the same time. To this end, the UE may transmit a beam recovery request trigger message from the RRC layer to the MAC/PHY layer or from the MAC layer to the PHY layer.

Conversely, when a beam problem is detected according to condition1 or condition2, the UE may transmit it to the upper layer to trigger the T310 timer. To this end, the UE may transmit a T310 trigger message from the PHY layer to the MAC/RRC layer or from the MAC layer to the RRC layer.

The channels (control channels) used to declare the beam failure and reference signals (RSs) for measurement of each channel may be RSs and channels scheduled in advance by the base station.

Candidates of the corresponding beam failure detection RS include a UE-specific resource scheduled CSI-RS with dedicated signal configured including a CSI-RS with resources/characteristics allocated only for the corresponding UE.

Alternatively, a candidate of the beam failure detection RS includes a Cell-specific resource scheduled CSI-RS with dedicated signal configured including a CSI-RS having a resource/characteristic allocated for a plurality of unspecified UEs.

Alternatively, the candidate beam failure detection RS includes an NR-Sync Signal (PSS, SSS, PBCH) including a synchronization signal and a broadcast channel signal having resources/characteristics allocated for a plurality of unspecified UEs.

The beams (such as a new candidate beam or RACH performing beam) used to perform the beam recovery may be RSs scheduled in advance by the base station or RSs that the terminal can measure by itself.

Candidates of the corresponding beam recovery identification RSs include UE-specific resource scheduled CSI-RS with dedicated signal configured including CSI-RS with resources/characteristics allocated only for the corresponding UE.

Candidates of the corresponding beam recovery identification RSs include Cell-specific resource scheduled CSI-RS with dedicated signal configured including CSI-RS with resources/characteristics allocated for multiple unspecified UEs.

Candidates for the corresponding beam recovery identification RSs include NR-Sync Signals (PSS, SSS, PBCH) including a synchronization signal and a broadcast channel signal with resources/characteristics allocated for multiple unspecified UEs.

The reference signals (RS) used to perform the cell level problem detection may be RSs scheduled in advance by the base station or can be measured by the terminal itself.

The RLF declaration method due to beam recovery failure will be described below.

According to an embodiment of the present disclosure, the UE may declare RLF when the performed beam recovery operations continue to fail. Specifically, the UE may declare RLF when beam recovery fails consecutively N_RLF1 times (NACK count or failure indication count).

In addition, the UE may declare RLF if it fails within Timer_RLF1.

In addition, the UE may declare RLF when it fails N_RLF2 times within Timer_RLF2. (even if discontinuous)

In addition, the UE may declare RLF when receiving an RLF declaration request DL signal from the network (or from Node-B) for a recovery attempt.

In addition, after the UE declares beam failure (according to Condition 1 or Condition 2 above), when it fails to attempt beam recovery beyond Timer_RLF3 at all (when Condition 3 is dissatisfied), the UE may declare RLF.

Referring to FIG. 1y , the transceiver 1y-10 of the terminal may transmit and receive signals. The transceiver 1y-10 may transmit and receive signals under the control of the controller 1y-30. The control unit 1y-30 of the terminal may control the overall operation of the terminal. The controller 1y-30 may control the terminal to perform the operations described with reference to FIGS. 2A to 2P .

For example, the control unit 1y-30 performs beam measurement on at least one transmission beam of the base station and at least one beam of the terminal, and transmits beam measurement information to the base station based on the beam measurement, , it is possible to control to receive downlink information transmitted from the new transmission beam of the base station. The new transmission beam of the base station may be changed based on the relationship between the current reception beam of the terminal and the new transmission beam of the base station included in the beam measurement information.

If the new transmit beam of the base station corresponds to the current receive beam of the terminal, the transmit beam of the base station may be changed without receiving a beam change indication message from the base station. If the new transmission beam of the base station does not correspond to the current reception beam of the terminal, the controller 1y-30 may control to receive a beam change indication message from the base station.

In addition, after a preset time elapses after transmitting the beam change indication message, the reception beam of the terminal and the transmission beam of the base station may be changed. The beam measurement information includes an indicator, and the indicator may indicate whether the terminal can receive the transmission beam of the base station as the current reception beam of the terminal.

The transceiver 1z-10 of the base station 1z-00 may transmit and receive signals. The transceiver 1z-10 may transmit and receive signals under the control of the controller 1z-30. The control unit 1z-30 of the base station may control the overall operation of the base station. The controller 1z-30 may control the base station to perform the operations described with reference to FIGS. 2A to 2P.

For example, the controller 1z-30 receives beam measurement information from the terminal, determines a transmission beam change of the base station for the terminal based on the beam measurement information, and includes the beam measurement information included in the beam measurement information. Based on the relationship between the current reception beam of the terminal and the new transmission beam of the base station, it is possible to control to change the transmission beam of the base station.

In addition, if the new transmission beam of the base station corresponds to the current reception beam of the terminal, the transmission beam of the base station may be changed without transmitting a beam change indication message. Also, when the new transmission beam of the base station does not correspond to the current reception beam of the terminal, the controller 1z-30 may control to transmit a beam change indication message to the terminal. In addition, after a preset time elapses after transmitting the beam change indication message, the transmission beam of the base station may be changed.

In addition, the beam measurement information includes an indicator,

The indicator may indicate whether the terminal can receive the transmission beam of the base station as the current reception beam of the terminal.

The embodiments disclosed in the present specification and drawings are merely provided for specific examples to easily explain the contents of the present invention and help understanding, and are not intended to limit the scope of the present invention. Therefore, the scope of the present invention should be construed as including all changes or modifications derived based on the technical spirit of the present invention in addition to the embodiments disclosed herein are included in the scope of the present invention.

Claims (20)

A method performed by a base station in a communication system, comprising:
transmitting a report configuration including information related to group-based beam reporting to the terminal;
transmitting at least one reference signal for measuring beams to the terminal; and
Receiving a measurement report including at least two reference signal received power (RSRP) corresponding to at least two beams related to a beam group from the terminal based on information related to the group-based beam report,
The at least two beams associated with the beam group correspond to reference signals simultaneously received by the terminal. delete The method of claim 1, wherein the length of each RSRP is 7 bits. According to claim 1,
The report configuration is transmitted through RRC (radio resource control) signaling,
The reference signal method, characterized in that it comprises a CSI-RS (channel state information reference signal). A method performed by a terminal in a communication system, comprising:
Receiving a report configuration including information related to group-based beam reporting from a base station;
receiving at least one reference signal for measuring beams from the base station;
identifying at least two beams related to a beam group, corresponding to reference signals simultaneously received by the terminal; and
and reporting a measurement report including at least two reference signal received power (RSRP) corresponding to the at least two beams related to the beam group, based on information related to the group-based beam report. Way. delete 6. The method of claim 5,
The length of each RSRP is characterized in that 7 bits. 6. The method of claim 5,
The report configuration is transmitted through RRC (radio resource control) signaling,
The reference signal method, characterized in that it comprises a CSI-RS (channel state information reference signal). In a base station of a communication system,
transceiver; and
connected to the transceiver,
Transmitting a report configuration including information related to group-based beam reporting to the terminal,
Transmitting at least one reference signal for measuring beams to the terminal,
a control unit configured to receive, from the terminal, a measurement report including at least two reference signal received power (RSRP) corresponding to at least two beams related to a beam group, based on information related to the group-based beam report;
The at least two beams associated with the beam group correspond to reference signals simultaneously received by the terminal. delete The base station according to claim 9, wherein the length of each RSRP is 7 bits. 10. The method of claim 9,
The report configuration is transmitted through RRC (radio resource control) signaling,
The reference signal is a base station, characterized in that it includes a CSI-RS (channel state information reference signal). In the terminal of a communication system,
transceiver; and
connected to the transceiver,
Receiving a report configuration including information related to group-based beam reporting from the base station,
Receive at least one reference signal for measuring beams from the base station,
Identifying at least two beams related to a beam group, corresponding to the reference signals simultaneously received by the terminal,
and reporting a measurement report including at least two reference signal received power (RSRP) corresponding to the at least two beams related to the beam group, based on information related to the group-based beam report. terminal. delete 14. The method of claim 13,
A terminal, characterized in that the length of each RSRP is 7 bits. 14. The method of claim 13,
The report configuration is transmitted through RRC (radio resource control) signaling,
The reference signal is a terminal, characterized in that it includes a CSI-RS (channel state information reference signal). delete delete delete delete

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