CN117979441A

CN117979441A - TDD uplink and downlink configuration method on NCR

Info

Publication number: CN117979441A
Application number: CN202410192148.3A
Authority: CN
Inventors: 于海鹏; 张樾晴; 荣宝; 王喆; 李鸿刚; 王玉林; 苏宁
Original assignee: Xi'an Fangwei Technology Co ltd; Inner Mongolia Dayan Mining Group Co ltd Zanihe Open Pit Mine
Current assignee: Xi'an Fangwei Technology Co ltd; Inner Mongolia Dayan Mining Group Co ltd Zanihe Open Pit Mine
Priority date: 2024-02-21
Filing date: 2024-02-21
Publication date: 2024-05-03

Abstract

The invention relates to the technical field of communication interaction, in particular to a TDD uplink and downlink configuration method on NCR, which solves the technical problem that NCR deployment modes in the prior art lack high-performance matching limit scenes, the scheme is based on the condition that NCR-MT and NCR-FWD in NCR work in the same frequency band, namely a control link, a return link and an access link adopt the same TDD uplink and downlink configuration, and the NCR-FWD defaults to not forward the information of gNB on a Flexible symbol of semi-static configuration; on the basis, two modes of transmitting physical beam characteristics and semi-static TDD uplink and downlink configuration are adopted respectively, the NCR is faced to a scene of enhancing communication signals, communication time delay can be reduced, a communication frame between gNB-UE is not changed, and the NCR is transparent to the UE.

Description

TDD uplink and downlink configuration method on NCR

Technical Field

The invention relates to the technical field of communication interaction, in particular to a TDD uplink and downlink configuration method on NCR.

Background

The NCR receives and processes side control information (side control information, SCI) from the network side on the basis of a radio frequency amplifier, and a network control repeater (network-controlled repeaters, NCR) performs amplification and forwarding operations more efficiently under the control of the SCI. Compared with a radio frequency amplifier, the transmission and reception with better space directivity can reduce unnecessary noise amplification, and simplify network integration;

The NCR comprises a control unit (mobile termination, MT) and a forwarding unit (FWD), wherein the NCR-MT part is responsible for receiving control information from the base station, and the NCR-FWD part is responsible for realizing communication between the base station and the user.

Coverage is a fundamental aspect of cellular network deployment, mobile operators rely on different types of network nodes to provide full coverage in their deployment; an Integrated Access and Backhaul (IAB) is introduced in the published version of the protocol R16, and enhanced as a new network node that does not require a wired backhaul in the published version of the protocol R17; another network node is a radio frequency repeater which amplifies and forwards only the received signal. While a radio frequency repeater provides a cost effective way to extend network coverage, because the radio frequency repeater simply performs the amplification and forwarding operations, it is not fully capable of considering various factors that may improve performance, including, for example, semi-static and/or dynamic downlink, uplink configuration, adaptive transmitter/receiver spatial beamforming, ON-OFF state, etc.

To further improve coverage, NCR is introduced in the "third generation partnership project (3 GPP)" in the published version of protocol R18 as an enhancement to conventional radio frequency repeater. The NCR has the ability to receive and process repeater control information from the network side. A system model of NCR is given in TR38.867 as shown in figure 1;

The NCR-MT is defined as a functional entity, and communicates with the gNB (5G base station) through a control link (C-link), so that SCI information interaction (such as providing control information for forwarding of NCR-FWD) is realized, and the control link is based on NRUu interfaces.

NCR-FWD is defined as a functional entity that enables the amplification and forwarding of UL/DL signals between the gNB and the UE through the backhaul link (B-link) and the access link (a-link). The NCR-FWD behavior is controlled according to the side control information received from the gNB.

In practical applications, it is important to study that the NCR-MT and the NCR-FWD operate in the same frequency band, and that at least one carrier of the NCR-MT should operate in the frequency band to which the NCR-FWD forwards. For operation in the same frequency band, the control link and backhaul link are expected to pass through the same channel massive properties.

The NCR, which is an enhancement of the radio frequency amplifier, can receive and process the side control information from the network, but is also a relay between the base station and the user, so that the NCR needs to synchronize the information and the state of the base station and the user, and also needs to ensure the service quality of the user. Therefore, the real deployment of NCR must consider its duplex operation mode, and designing a complete transmission flow of signaling and information is a problem to be solved.

In addition, the process also needs to meet high performance and high matching of scenes; specifically, the process can realize efficient utilization of frequency spectrum, ensure flexibility of 3 links (control link, backhaul link and access link), and better adapt to asymmetric traffic, namely, the situation of partial limit scenes, such as indoor signal enhancement, cell edge user signal enhancement and enhancement of mobile equipment on two sides of a highway.

Disclosure of Invention

The invention provides a TDD uplink and downlink configuration method on NCR, which aims to solve the technical problem that the NCR deployment mode in the prior art lacks high-performance matching limit scenes.

In order to solve the technical problems, the technical scheme of the invention is as follows:

a TDD uplink and downlink configuration method on NCR is suitable for indoor signal enhancement and hot spot area enhancement coverage scenes, and comprises the following steps:

The NCR has the capability to configure the UE to access the link beam, the beam of the access link being indicated by the NCR;

First, for the gNB to NCR link: the network configuration firstly realizes semi-static configuration through message bodies of tdd-UL-DL-ConfigurationCommon and tdd-UL-DL-ConfigurationDedicated of RRC signaling;

The uplink and downlink symbols are used for transmitting UE information, and are configured according to the flow of legal UE;

For a Flexible symbol after semi-static configuration, the NCR-MT adopts dynamic configuration and receives SFI or DCI from gNB to carry out uplink and downlink configuration on the Flexible symbol, and meanwhile, the uplink and downlink symbol conversion interval is reserved;

the interactive information of the gNB and the UE is transmitted in the semi-statically configured uplink and downlink symbols;

the interactive information of NCR and UE is transmitted in the uplink and downlink symbols which are configured dynamically;

SCI information between the gNB and NCR is transmitted over the control link;

in the TDD uplink and downlink configuration, the NCR-MT decodes the SIB1 message to obtain uplink and downlink subframe configuration consistent with legal UE operation;

the backhaul link beam selection is:

Firstly, when time domain resources for simultaneous downlink reception or uplink transmission exist in a control link and a return link, the return link defaults to use the same wave beam as the control link;

Secondly, in the time domain resource without simultaneous downlink reception or uplink transmission in the control link and the backhaul link, if the NCR does not support the capability of new signaling for backhaul beam indication or the dedicated signal is not used for beam indication of the backhaul link, the following manner is adopted:

When the control link uses the beam indication framework of R15/16, the space relation of the beam and the PUCCH resource ID which are determined by the QCL assumption of CORESET with the smallest ID in the control link and are the smallest is respectively applied to the DL and the UL of the backhaul link in a predefined rule mode;

When the control link adopts a Rel-17 beam indication framework, unified TCI for the control link is used for indicating UL and DL of the return link respectively;

Dedicated signaling, under semi-static beam indication, when NCR-MT applies beam indication frame of R15, UL beam of return link selects a TCI state ID from beam list of control link indicated by RRC signaling through MAC CE indication; the UL beam is indicated by SRI and one reference signal on the control link is indicated by MAC CE. If NCR-MT applies R17 framework, DL and UL beams are indicated by MAC CE, selecting a TCI state ID from beam list of RRC configured control link;

second, for the NCR to UE link:

the NCR-MT uses the part of Flexible symbol to bear the interactive information of the NCR and the UE;

In the semi-static configuration, gNB configures a time slot UL-DL through cell-level and UE-level signaling, after receiving gNB TDD configuration, NCR sends down UE-Group SFI signaling and UE-SPECIFIC DCI signaling through dynamic configuration or receiving control signaling from gNB, so as to reconfigure a Flexible symbol for carrying signaling interaction between NCR and UE;

the remainder of the message from the gNB is forwarded by the NCR-FWD to the UE.

Specifically, the method further comprises the following steps: the NCR-UE beam pairing process specifically comprises the following steps:

initial beam selection and pairing between NCR and UE is achieved;

The messages of beam measurement, beam reselection and the like are forwarded to the gNB by the NCR, and the gNB makes a decision;

When the environment changes, the NCR-MT receives the beam measurement information and autonomously decides whether to perform beam reselection.

Specifically, the interaction information of the NCR and the UE includes: configuration of a beam set of an access link and failed reselection;

the NCR-MT autonomously scans the wave beam and selects the wave beam pair with the best signal quality;

in case of beam failure, beam reselection with the UE is achieved.

Specifically, a beam between NCR and UE adopts semi-static configuration to perform periodic detection reselection;

when the beam failure occurs, the terminal firstly determines an alternative beam, then reports the L1-RSRP measured value to the NCR, and if the terminal does not detect the response sent by the network within a certain time period, the terminal retransmits the recovery request after the power is increased according to the configured power increasing parameter;

The NCR initiates a beam reselection mechanism to re-pair the beams.

Specifically, based on the gNB and NCR being located at fixed positions, the environment between the gNB and NCR is slow in change, and the possibility of beam failure is low;

when beam failure occurs, reconfiguration is performed according to the configuration flow between the NCR and the UE.

In addition, the invention provides a TDD uplink and downlink configuration method on NCR, which is suitable for the scene of enhancing the edge user signal and enhancing the high-speed mobile equipment:

The control link configures a time slot structure by semi-static uplink and downlink configuration signaling;

Firstly, adopting tdd-UL-DL-ConfigurationCommon signaling to configure a common time slot structure;

Secondly, adopting RRC signaling tdd-UL-DL-ConfigurationCDedicated to configure a special time slot structure for NCR;

The DL and the UL contain channel information, control information and data information to be issued by the gNB;

The Flexible part is in an unconfigured state, and side control information is configured for the Flexible part by adopting tdd-UL-DL-ConfigurationDedicated signaling setting;

the side control information includes: an activation state, a TDD uplink and downlink direction, an access link beam set and a backhaul link beam set;

in the configuration flow of TDD uplink and downlink:

The C-link transmits SCI information on a Flexible symbol, and the uplink and downlink states of the Flexible symbol are configured by a UE-level RRC message;

After information is transmitted to NCR, NCR-MT decodes side control information in Flexible and configures NCR-Fwd, and information in DL/UL is not decoded, and NCR-Fwd directly forwards partial information to UE through A-link;

the NCR-Fwd defaults to not forward the information of the base station ON the Flexible symbol, namely the Flexible symbol in the signaling is not forwarded in an ON state or is in an OFF state;

Based on the fixed positions of the gNB and the NCR, the C-link and the B-link are expected to experience the same large-scale attribute of the channel, namely, at least when the NCR-MT and the NCR-Fwd work in the same frequency band, the B-link adopts the same wave beam as the C-link, and feedback information and UE context information are added to feed back and interact through the B-link.

Specifically, because the positions of the gNB and the NCR are fixed, the propagation environment basically does not change after the beam is selected, and the requirement can be met by adopting a semi-persistent scheduling mode, namely:

When the time slot structure transmitted by gNB-NCR only transmits in a fixed period, and NCR-MT also only receives in a fixed period;

After the semi-persistent scheduling is activated, the NCR uses the transmission parameters indicated by the PDCCH activation according to the RRC configuration period to periodically receive the downlink data, so that the control signaling is used only once, and the signaling overhead can be reduced.

Specifically, the UE may be selected as one or more devices, and due to mobility of the terminal, a situation that channel quality is suddenly degraded or interference is suddenly aggravated due to a change of a propagation environment is easily caused, and a scheduling manner of combining semi-persistent scheduling and dynamic scheduling is adopted, which specifically is:

the scheduling mode of the initial state is configured the same as the scheduling mode of the gNB-NCR, but the scheduler adopts the dynamic signaling of the scheduling terminal;

when no emergency exists, the terminal can always use a mode to configure uplink and downlink, but when an emergency exists, the dynamic scheduler can timely change the uplink and downlink configuration, so that the measurement information of the terminal can be timely fed back to NCR, then the NCR feeds back to gNB, and finally the gNB timely regulates and controls the whole channel.

Specifically, a signal measurement threshold is set at the NCR.

Specifically, beam measurement and reporting are performed by the terminal UE;

The terminal reports the measured signal measured value (M) to the NCR each time the terminal receives a signal, and when the signal measured value (M) < RSRP, the NCR immediately reports the measured signal measured value (M) to the gNB;

meanwhile, the terminal firstly determines alternative beams and then reports the L1-RSRP measured value to the NCR;

And in a certain time period, the terminal does not detect the response sent by the network, and retransmits the recovery request after the power is increased according to the configured power increasing parameter.

The invention has the following beneficial effects:

The scheme is based on the condition that NCR-MT and NCR-FWD in NCR work in the same frequency band, namely the control link, the backhaul link and the access link adopt the same TDD uplink and downlink configuration, and the NCR-FWD defaults to not forward the information of gNB on a flexible symbol of semi-static configuration. On the basis, two modes of transmitting physical beam characteristics and semi-static TDD uplink and downlink configuration are adopted respectively, the NCR is faced to a scene of enhancing communication signals, communication time delay can be reduced, a communication frame between gNB-UE is not changed, and the NCR is transparent to the UE.

For the scene of indoor signal enhancement and hot spot area enhancement coverage, the method is more suitable for the mode of interactive selection of the beam of the access link by the NCR and the user, and the scheme can increase the flexibility of operation; the NCR-MT bears more and accesses the signaling interaction of UE, such as beam reporting and reconfiguration, so that the time delay can be reduced, the load pressure at the gNB can be reduced, and the network congestion problem can be relieved; SCI information transmission is realized by using a semi-static configured Flexible symbol, so that time-frequency resources can be fully utilized, and the influence of NCR on a network is reduced.

For the scene of enhancing the user signals at the cell edge and enhancing the mobile equipment at the two sides of the highway, the method is more suitable for the configuration of the physical beam related information supported by NCR-FWD by gNB through OAM, the NCR adopting the scheme is configured by gNB, the inter-station interference can not occur, and the user and the NCR do not need frequent interaction. For idle Flexible symbols, a ray tracing function may be added to the scene as appropriate.

The invention is mainly used for solving the work mode of NCR and providing a corresponding flow, wherein various performance indexes such as frequency band utilization rate, time delay and user service quality are considered in the flow, and the optimal solution for reaching the indexes is sought. In addition to this, a solution is presented which considers how to solve the problem of the communication link encountering an emergency.

Therefore, the invention has the advantages that the optimal selection of the NCR working mode can effectively improve the frequency band utilization rate, reduce the time delay and improve the user service quality; the original signaling is not changed, so that the signaling complexity and equipment cost of the base station and NCR can be effectively reduced; the method is more suitable for and highly fits some special scenes, such as heterogeneous flow, asymmetric flow and environments with limited frequency spectrum resources; the method combines semi-persistent scheduling and dynamic scheduling, the signaling overhead can be reduced and troublesome inter-station interference can be avoided by adopting the semi-persistent scheduling method in the first hop, the reconfigured time delay can be reduced by adopting the semi-persistent and dynamic scheduling method in the second hop, and the scene requirement of high reliability and low time delay of 5G is met; the problem of the terminal signal terminal caused by the poor channel environment can be solved in time.

Drawings

The invention is described in further detail below with reference to the drawings and the detailed description.

FIG. 1 is a model of an NCR system;

FIG. 2 is an indoor NCR deployment scenario diagram of the present invention;

FIG. 3 is a diagram of a remote zone NCR deployment scenario of the present invention;

fig. 4 is a diagram of a deployment scenario of a cell edge NCR according to embodiment 2 of the present invention;

FIG. 5 is a NCR deployment scenario diagram of the communication enhancement of high-speed mobile devices on both sides of a highway according to embodiment 2 of the present invention;

Fig. 6 is a diagram of tdd-UL-DL-ConfigurationCommon signaling setup time slots in embodiment 2 of the present invention;

Fig. 7 is a diagram of tdd-UL-DL-ConfigurationDedicated signaling setup time slots in embodiment 2 of the present invention;

Fig. 8 is a layout of side control information in a slot structure according to embodiment 2 of the present invention;

Fig. 9 is a TDD uplink and downlink configuration flow chart of embodiment 2 of the present invention.

Reference numerals in the drawings denote:

gNB,5G base station;

UE, user;

NCR-MT responsible for receiving control information from the base station;

NCR-Fwd is in charge of realizing communication between a base station and a user;

DL, data link;

UL, uplink.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, based on the embodiments of the application, which a person of ordinary skill in the art would obtain without inventive faculty, are within the scope of the application; it should be noted that, for convenience of description, in the present application, a "left side" is a "first end", a "right side" is a "second end", an "upper side" is a "first end", and a "lower side" is a "second end" in the present view, and the description is for clearly expressing the technical solution, and should not be construed as unduly limiting the technical solution of the present application.

To facilitate an understanding of the technical solution of the present invention, some technical terms are given herein to facilitate an understanding of those skilled in the art;

beam information: the method mainly comprises the steps of selecting wave beams of a control link, a return link and an access link; the control link and backhaul link may use fixed beams or adaptive beams; if a fixed beam, the initial configuration cannot be changed. If the carrier of the NCR-MT operates in the band forwarded by the NCR-Fwd, then the TCI state of the beam of the NCR-Fwd in the backhaul link is assumed to be the same as the beam of the control link.

For adaptive beams, there are two options:

The new signaling indicates the beam used by the backhaul link: the new signaling is dynamic signaling and/or semi-static signaling (e.g., RRC signaling/MAC CE) indicating one or more of a set of beams of the control link.

Predefined rule decision: if there are slots/symbols (time resources) for DL reception/UL transmission in both the control link and the backhaul link, the beam of the backhaul link is the same as the beam of the control link. Otherwise, the beam of the backhaul link will be selected from the beam set of the control link.

Access link: the access link beam of the NCR-FWD is indicated by a beam index, either dynamic or semi-static indication may be employed. A single beam indication may indicate multiple beams. Considering that UL and DL beams corresponding to an access link of the NCR-FWD are represented by the same beam index, a specific forwarding direction may be based on a time domain resource indication or a TDD UL/DL configuration. (NCR-FWD defaults to not forward on flexible symbols for semi-static indication)

Timing information: and utilizing the timing strategy of legal UE.

UL-DL TDD configuration: the protocol provides support for semi-static configuration, and the same TDD uplink and downlink configuration is adopted for a backhaul link and an access link; if the NCR-MT and the NCR-FWD operate in the same frequency band, the control link, the backhaul link, and the access link are configured with the same TDD uplink and downlink.

Switching information: if the gNB does not make explicit or implicit indication, the NCR-FWD is in a closed state by default.

NCR power control: the power control is achieved by introducing an amplification gain parameter.

In connection with the description of NCR in the protocol, the present solution focuses on unified SCI information transmission between the gNB, NCR and UE in the TDD framework under the same frequency band.

Note that, a Flexible symbol is a generic term for a Flexible symbol, and can be regarded as a type of mark; the whole link information is divided into two parts after being transmitted to NCR, specifically: with and without F-marks;

The information stored in the time slot marked by the Flexible symbol with the F mark is decoded by the NCR-MT and the NCR-Fwd is configured; the information without the Flexible symbol mark (UL/DL) is not decoded and is directly forwarded by NCR-Fwd to the UE over the a-link.

Example 1

The scene involved in the method specifically comprises the following steps: for indoor signal enhancement and scene of hot spot area enhancement coverage;

Cellular networks can be used in high density building urban areas covered with indoor users, while also providing access to large geographic areas in remote rural areas, which can be challenging to achieve full coverage due to large scale shadow fading of the connection distance from the base station or the connection with the base station for the most part. The following are two scenario concepts for NCR deployment:

(1) An indoor environment, as shown in fig. 2;

the signaling interaction between the NCR and the UE is realized by adopting dynamic TDD uplink and downlink configuration, so that the requirements of different services can be met, and the scheduling flexibility is improved. The NCR is deployed in an indoor environment, so that interference with other cells can be reduced, and meanwhile, the service quality of the cells is improved.

(2) Remote area network range expansion, as shown in figure 3;

the base station deployment in the remote area is inconvenient, and because of the influence of the terrain environment, the network coverage area is small, and the NCR can be deployed to enlarge the network coverage area;

and the inter-cell interference is not easy to be caused due to the fact that the inter-cell distance between adjacent cells in a remote area is far.

In this scheme the NCR has the capability to configure the UE to access the link beam, the beam of the access link being indicated by the NCR;

For the gNB to NCR link:

Network configuration first achieves semi-static configuration through the tdd-UL-DL-ConfigurationCommon and tdd-UL-DL-ConfigurationDedicated message bodies of RRC signaling,

The uplink and downlink symbols are used for transmitting UE information, and are configured according to the flow of legal UE.

For the Flexible symbol after semi-static configuration, the NCR-MT adopts dynamic configuration (receiving SFI or DCI from gNB) to carry out uplink and downlink configuration on the Flexible symbol, and meanwhile, the uplink and downlink symbol conversion interval is reserved. The interactive information of gNB and UE is transmitted in semi-static configured uplink and downlink symbols, and the interactive information of NCR and UE is transmitted in dynamic configured uplink and downlink symbols. SCI information between the gNB and NCR is transmitted over the control link.

SCI control information content, TDD uplink and downlink configuration: the NCR-MT decodes the SIB1 message to obtain the configuration of the uplink and downlink subframes (consistent with the operation of legal UE);

Backhaul link beam selection:

(1) When there is time domain resource of simultaneous downlink reception or uplink transmission in the control link and the backhaul link, the backhaul link defaults to use the same beam as the control link

(2) In the time domain resources without simultaneous downlink reception or uplink transmission in the control link and the backhaul link, if the NCR does not support the capability of new signaling for backhaul beam indication or the dedicated signal is not used for beam indication of the backhaul link, the following scheme is adopted:

Predefined rules apply the spatial relationship of minimum beam and PUCCH resource ID determined by the QCL assumption of CORESET with minimum ID in the control link to DL and UL of the backhaul link, respectively, when the control link uses the beam indication framework of R15/16. When the control link employs a Rel-17 beam indication framework (i.e., unified TCI framework), the unified TCI for the control link is used to indicate UL and DL, respectively, of the backhaul link.

Dedicated signaling, under semi-static beam indication, when NCR-MT applies beam indication frame of R15, UL beam of return link selects a TCI state ID from beam list of control link indicated by RRC signaling through MAC CE indication; the UL beam is indicated by SRI and one reference signal on the control link is indicated by MAC CE. If NCR-MT applies R17 framework, DL and UL beams are indicated by MAC CE, a TCI status ID is selected from the beam list of RRC configured control links.

For the NCR-to-UE link, 3GPP R18 specifies that NCR-FWD does not support message forwarding on the Flexible symbol after semi-static configuration, we consider that NCR-MT carries the interactive information of NCR and UE with the part of Flexible symbol;

In the semi-static configuration, gNB configures the time slot UL-DL through cell-level and UE-level signaling, after receiving gNB TDD configuration, NCR realizes reconfiguration of Flexible symbols through dynamic configuration (or receiving gNB control signaling) UE-Group SFI signaling (DCI format_0 issue) and UE-SPECIFIC DCI signaling (DCI format0,1 issue), and is used for carrying signaling interaction of NCR and UE, and the rest of the message from gNB is forwarded to the UE by NCR-FWD.

The NCR-UE beam pairing, under the unified control of gNB, realizes the initial beam selection and pairing between NCR and UE in general cases; and the messages such as beam measurement, beam reselection and the like are forwarded to the gNB by the NCR, and the gNB makes decisions. Due to the existence of the intermediate node NCR, the environment information cannot be fed back in time, and operations such as beam reselection and the like are performed. The scheme considers that the NCR-MT is responsible for beam selection between the UE and the NCR-MT receives beam measurement information when the environment changes, autonomously decides whether to perform beam reselection or not, can reduce delay, and simultaneously increases the flexibility of operation.

And the message is carried on the Flexible symbol, and as the NCR and the UE autonomously perform beam information interaction, the interaction information of the NCR and the UE needs to comprise a beam set of an access link and configuration of failed reselection without the participation of gNB. The NCR-MT autonomously performs beam scanning (SSB), and selects a beam pair with the best signal quality; in case of beam failure, beam reselection with the UE is achieved. Other synchronization information is still uniformly controlled by the base station.

Specifically, the beam between NCR and UE adopts semi-static configuration to perform periodic detection reselection (specific periodic configuration reference gNB and beam configuration between UE);

when the beam failure occurs, the terminal firstly determines an alternative beam, then reports the L1-RSRP measured value to the NCR, and if the terminal does not detect the response sent by the network within a certain time period (within 4 time slots), the terminal retransmits a recovery request after the power is increased according to the configured power increasing parameter; the NCR initiates a beam reselection mechanism to re-pair the beams. (similar to legal UE configuration procedure)

Considering that the gNB and the NCR are located at fixed positions, the environment between the gNB and the NCR changes slowly, and the possibility of beam failure is small, if beam failure occurs, the configuration is performed according to the configuration flow between the NCR and the UE (the periodic reselection time can be set to a larger value, and the specific time is not considered here).

Example 2

For enhancing cell edge coverage as shown in fig. 4;

Users at the cell edge may experience signal interruption or continuous handover under the coverage of the base stations of two neighboring cells due to weak coverage strength of the base station center, which may affect the quality of service of the users. If NCR is used as a relay between a base station and a user, inter-station interference is avoided because NCR is configured by the gNB and the user does not need frequent interaction with NCR, which brings the user with a good experience and reduces communication delay.

For the enhancement of high speed mobile devices on both sides of the highway, as shown in fig. 5;

Lower latency is required due to the mobility of the user, and unified configuration by the base station will reduce frequent interactions of the user with the NCR;

And the Flexible of the NCR is not forwarded so as to be idle in the time domain of some OFDM symbols, and a ray tracing function can be added to the scene by proper selection.

The control link configures the time slot structure by semi-static uplink and downlink configuration signaling, firstly configures a public time slot structure by using tdd-UL-DL-ConfigurationCommon signaling, and secondly configures a special time slot structure for NCR by using RRC signaling tdd-UL-DL-ConfigurationCDedicated.

① Tdd-UL-DL-ConfigurationCommon signaling setup as shown in fig. 6;

The DL and UL include channel information, control information and data information to be issued by the gNB. The Flexible portion is in an unconfigured state at this time.

② On the basis of ①, carrying out configuration of side control information on the Flexible part by adopting tdd-UL-DL-ConfigurationDedicated signaling; as shown in fig. 7;

In fig. 8, it is: the side control information includes an activation state, an uplink and downlink direction, a set of access link beams, and a set of backhaul link beams.

In fig. 9, the C-link transmits SCI information on the Flexible symbol (uplink and downlink states of the Flexible symbol are configured by the UE-level RRC message), after the information is transmitted to the NCR, the NCR-MT decodes the side control information in the Flexible and configures the NCR-Fwd, and the information in the DL/UL is not decoded, and the NCR-Fwd directly forwards the part of the information to the UE through the a-link. The NCR-Fwd defaults to not forward the information of the base station ON the Flexible symbol, namely the Flexible symbol in the signaling is not forwarded in an ON state or is in an OFF state;

Since the gNB and NCR are fixed in location, C-link and B-link are expected to experience the same channel massive properties, i.e., channel properties in type A and type D (if applicable) (at least when NCR-MT and NCR-Fwd are operating in the same frequency band). And B-link adopts the same wave beam as C-link, and feedback and interaction are performed through B-link after feedback information and UE context information are added.

Adopts a mode of combining semi-persistent scheduling and dynamic scheduling

(1) Because the positions of the gNB and the NCR are fixed, the propagation environment is not changed basically after the beam is selected, and therefore, the requirement can be met by adopting a semi-persistent scheduling mode. I.e. the slot structure transmitted by the gNB-NCR is transmitted only for a fixed period T (e.g. t=5 ms, 2.5ms, 2ms when the subcarrier spacing is 15 khz) and the NCR-MT is also received only for a fixed period. After the semi-persistent scheduling is activated, the NCR periodically receives downlink data by using the transmission parameters indicated by the PDCCH activation according to the period T configured by the RRC. Therefore, only one control signaling is used, so that signaling overhead can be reduced, and troublesome inter-station interference can be avoided in the manner.

(2) In NCR-UE, the UE may be one or more devices, and since mobility of the terminal is easy to cause a situation that channel quality is suddenly degraded or interference is suddenly aggravated due to a change of a propagation environment, a scheduling manner combining semi-persistent and dynamic scheduling is adopted. The scheduling mode of the initial state is configured the same as the scheduling mode of the gNB-NCR, but the scheduler adopts dynamic signaling of the scheduling terminal. When no emergency exists, the terminal can always use a mode to configure uplink and downlink, but when an emergency exists, the dynamic scheduler can timely change the uplink and downlink configuration, so that the measurement information of the terminal can be timely fed back to NCR, then the NCR feeds back to gNB, and finally the gNB timely regulates and controls the whole channel. The whole process can reduce the reconfiguration time delay and can meet the scene requirement of 5G high reliability and low time delay.

Consider that an emergency situation is encountered, such as a sudden degradation of the channel environment, resulting in a very poor or even an interruption of the terminal signal, and therefore consider setting a signal measurement threshold (RSRP) at the NCR.

The specific process comprises the following steps: beam measurement and reporting are performed by the terminal UE, which reports the measured signal measurement value (assumed to be M) to the NCR each time the terminal receives a signal, and when M < RSRP, the NCR immediately reports to the gNB. Meanwhile, the terminal firstly determines the alternative wave beam, then reports the L1-RSRP measured value to the NCR, and if the terminal does not detect the response sent by the network within a certain time period (within 4 time slots), the terminal retransmits the recovery request after the power is increased according to the configured power increasing parameter.

It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the invention.

Claims

1. The method for configuring the TDD uplink and downlink on the NCR is suitable for indoor signal enhancement and hot spot area enhancement coverage scenes, and is characterized by comprising the following steps:

SCI information between the gNB and NCR is transmitted over the control link;

the backhaul link beam selection is:

second, for the NCR to UE link:

2. The method for configuring TDD uplink and downlink on NCR according to claim 1, further comprising: the NCR-UE beam pairing process specifically comprises the following steps:

initial beam selection and pairing between NCR and UE is achieved;

3. The method for TDD uplink and downlink configuration on NCR according to claim 2, wherein the interaction information between NCR and UE includes: configuration of a beam set of an access link and failed reselection;

in case of beam failure, beam reselection with the UE is achieved.

4. The method for configuring TDD uplink and downlink on NCR according to claim 3, wherein a beam between NCR and UE adopts semi-static configuration to perform periodic detection reselection;

The NCR initiates a beam reselection mechanism to re-pair the beams.

5. The method for TDD uplink and downlink configuration on NCR according to claim 4, wherein, based on the gNB and NCR being located at fixed positions, the environment between the gNB and NCR changes slowly, and there is less possibility of beam failure;

6. The method for configuring the TDD uplink and downlink on the NCR is suitable for the scene of enhancing the edge user signal and enhancing the high-speed mobile equipment, and is characterized in that:

in the configuration flow of TDD uplink and downlink:

7. The method for TDD uplink and downlink configuration on NCR according to claim 6, wherein, because the locations of the gNB and NCR are fixed, the propagation environment after beam selection is not changed basically, and the requirement can be satisfied by adopting a semi-persistent scheduling mode, namely:

8. The method for TDD uplink and downlink configuration on NCR according to claim 7, wherein in NCR-UE, UE can be selected as one or more devices, and the mobility of the terminal is easy to cause sudden degradation of channel quality or sudden aggravation of interference due to the change of propagation environment, and a scheduling manner combining semi-persistent and dynamic scheduling is adopted, specifically:

9. The method for TDD uplink and downlink configuration on an NCR according to claim 8, wherein a signal measurement threshold (RSRP) is set at the NCR.

10. The method for TDD uplink and downlink configuration on NCR according to claim 9, wherein beam measurement and reporting are performed by a terminal UE;