CN112423329A

CN112423329A - Method, device and system for determining PSCell by master node in dual-connection system

Info

Publication number: CN112423329A
Application number: CN201910786432.2A
Authority: CN
Inventors: 张路; 刘继民
Original assignee: Nokia Shanghai Bell Co Ltd
Current assignee: Nokia Shanghai Bell Co Ltd
Priority date: 2019-08-23
Filing date: 2019-08-23
Publication date: 2021-02-26

Abstract

The application aims to provide a method, a device and a system for determining a PSCell by a main node in a dual-connection system. In order to allow an efficient estimation of SINR when required reference signals and unwanted reference signals (i.e. interference) are transmitted over orthogonal resources, the present application proposes a novel RSRP-based SINR estimation method. Specifically, a ratio of "RSRP measured by the user equipment on a to-be-detected carrier corresponding to the candidate PSCell in a sector to which the candidate PSCell belongs" to "a sum of one or more RSRPs measured by the user equipment on the same to-be-detected carrier in at least one adjacent sector of the sector and an AWGN average power corresponding to the user equipment" is defined as an SINR based on the RSRP. The master node uses this parameter to select a PSCell from the candidate pscells. Compared with the method for selecting the PSCell only by using RSRP in the current industry, the method provided by the present application can realize more reliable PSCell selection because of the effective SINR estimation.

Description

Method, device and system for determining PSCell by master node in dual-connection system

Technical Field

The present application relates to the field of communications, and in particular, to a technique for determining a PSCell by a master node in a dual connectivity system.

Background

Dual Connectivity (DC) is one of the key technologies of the 5G NR (New Radio) system. Based on the dual connectivity technology, a User Equipment (UE) is connected to two base stations simultaneously. One of the base stations is called a Master Node (MN), and the other base station is called a Secondary Node (SN). The control plane functionality of the UE is handled by the MN, which is typically a macro base station, while the user plane functionality may be handled by the MN, the SN, or both.

In the 3GPP standard, a dual connectivity working mode is previously defined for a 4G LTE (Long Term Evolution) network; currently, for 5G NR networks, a dual-connectivity operating mode is also defined, whether for independent networking (SA) deployment or Non-independent Networking (NSA) deployment.

When an auxiliary node is added in a dual connectivity operating mode, that is, when a PSCell (Primary Secondary Cell) is determined, how to select an appropriate PSCell from candidate pscells is a problem to be solved in the dual connectivity technology. The PSCell is a Primary Cell (Primary Cell) on which the user equipment only initiates random access in an SCG (Secondary Cell group) configured on a dual-connected SN.

Disclosure of Invention

The application aims to provide a method, a device and a system for determining a PSCell by a main node in a dual-connection system.

According to an embodiment of the present application, there is provided a method of determining a PSCell by a master node in a dual connectivity system, wherein the method includes the steps of:

acquiring Reference Signal Receiving Power (Reference Signal Receiving Power) measured by user equipment on a to-be-detected carrier corresponding to a candidate PSCell in a sector to which the candidate PSCell belongs and one or more RSRPs measured by the user equipment on the same to-be-detected carrier on at least one adjacent sector of the sector, wherein the user equipment is dual-connectable;

acquiring the average power of AWGN (Additive White Gaussian Noise) corresponding to the user equipment;

taking the RSRP measured by the user equipment on a to-be-detected carrier corresponding to the candidate PSCell in the sector to which the candidate PSCell belongs as a first parameter;

taking the sum of one or more RSRPs measured on the same carrier to be detected on the at least one adjacent sector and the AWGN average power as a second parameter;

estimating a Signal to Interference plus Noise Ratio (SINR) based on the RSRP according to a Ratio of the first parameter to the second parameter;

and if the estimated SINR based on the RSRP is larger than a preset threshold value, taking the candidate PSCell as the PSCell of the user equipment.

Optionally, the step of obtaining the AWGN average power corresponding to the user equipment includes:

estimating the AWGN average power corresponding to the user equipment; and/or

Employing the AWGN average power reported by the user equipment from measurements.

Optionally, the step of obtaining an RSRP measured by the user equipment on a to-be-detected carrier corresponding to the candidate PSCell in the sector to which the candidate PSCell belongs and one or more RSRPs measured by the user equipment on the same to-be-detected carrier in at least one adjacent sector of the sector includes:

and according to an event triggering mechanism and/or a periodic reporting mechanism, enabling the user equipment to report the RSRP measured on the carriers to be detected corresponding to the candidate PSCells in the sector and report one or more RSRPs measured on the same carriers to be detected on at least one adjacent sector of the sector.

Optionally, the measurement reporting trigger event for the event trigger mechanism includes at least any one of a B1 event, a B2 event, and an a4 event.

Optionally, the method further comprises:

and if the measurement time exceeds a preset time or the number of the measurement reports exceeds a preset number, releasing the measurement report triggering event.

Optionally, the method further comprises:

when the user equipment needs to perform the handover based on the mobility, the measurement reporting trigger event is released, and after the user equipment completes the handover based on the mobility, the corresponding measurement reporting trigger event is reconfigured for the user equipment through a wireless interface.

Optionally, the method further comprises:

and releasing and/or reconfiguring a measurement reporting trigger event for enabling the user equipment to report the RSRP after the user equipment finishes judging whether the candidate PSCell can be used as the PSCell.

According to another embodiment of the present application, there is also provided a computer-readable storage medium having stored thereon computer instructions for causing an apparatus to perform at least the following:

acquiring RSRP (reference signal received power) measured by user equipment on a to-be-detected carrier corresponding to a candidate PSCell in a sector to which the candidate PSCell belongs and one or more RSRPs measured by the user equipment on the same to-be-detected carrier on at least one adjacent sector of the sector, wherein the user equipment is user equipment capable of being in double connection;

acquiring AWGN average power corresponding to the user equipment;

estimating an RSRP based SINR according to a ratio of the first parameter to the second parameter;

There is also provided, in accordance with another embodiment of the present application, apparatus including:

at least one processor; and

at least one memory having a computer program stored thereon;

the at least one memory and the computer program are configured to, with the at least one processor, cause the apparatus to perform:

acquiring AWGN average power corresponding to the user equipment;

There is also provided, in accordance with another embodiment of the present application, a master node for determining a PSCell in a dual connectivity system, wherein the master node includes:

a device configured to obtain an RSRP measured by a user equipment on a to-be-detected carrier corresponding to a candidate PSCell in a sector to which the candidate PSCell belongs and one or more RSRPs measured by the user equipment on a same to-be-detected carrier in at least one adjacent sector of the sector, where the user equipment is a dual-connectable user equipment;

means for obtaining AWGN average power corresponding to the user equipment;

means for taking RSRP measured by the user equipment on a to-be-detected carrier corresponding to a candidate PSCell in a sector to which the candidate PSCell belongs as a first parameter;

means for summing the sum of the measured one or more RSRPs on the same to-be-detected carrier on the at least one neighboring sector and the AWGN average power as a second parameter;

means for estimating an RSRP based SINR according to a ratio of the first parameter to the second parameter;

means for determining whether to treat the candidate PSCell as a PSCell for the user equipment in accordance with whether the estimated RSRP based SINR is greater than a predetermined threshold.

Optionally, the means for obtaining the AWGN average power corresponding to the user equipment is configured to:

estimating the AWGN average power corresponding to the user equipment; and/or

Optionally, the means for acquiring an RSRP measured by the user equipment on a to-be-detected carrier corresponding to the candidate PSCell in the sector to which the candidate PSCell belongs and one or more RSRPs measured by the user equipment on the same to-be-detected carrier in at least one adjacent sector of the sector is configured to:

Optionally, the master node further includes:

means for determining whether to release the measurement reporting trigger event based on whether a measurement time exceeds a predetermined time period or whether a number of measurement reports exceeds a predetermined number.

Optionally, the master node further includes:

means for releasing the measurement reporting trigger event when the ue needs to perform mobility-based handover, and reconfiguring a corresponding measurement reporting trigger event for the ue through a wireless interface after the ue completes the mobility-based handover.

Optionally, the master node further includes:

means for releasing and/or reconfiguring a measurement reporting trigger event for causing the user equipment to report RSRP after the user equipment completes the determination of whether the candidate PSCell can be used as a PSCell.

There is also provided, in accordance with another embodiment of the present application, a system for determining a PSCell by a primary node in a dual connectivity system, including one or more user equipments, one or more secondary nodes, and a primary node as claimed in any one of the above.

In order to allow an efficient estimation of SINR when required reference signals and unwanted reference signals (i.e. interference) are transmitted over orthogonal resources, the present application proposes a novel RSRP-based SINR estimation method. Specifically, a ratio of "RSRP measured by the user equipment on a to-be-detected carrier corresponding to the candidate PSCell in a sector to which the candidate PSCell belongs" to "a sum of one or more RSRPs measured by the user equipment on the same to-be-detected carrier in at least one adjacent sector of the sector and an AWGN average power corresponding to the user equipment" is defined as an SINR based on the RSRP. The master node uses this parameter to select a PSCell from the candidate pscells. Compared with the method which only uses RSRP to select the PSCell and is adopted in the industry at present, the method provided by the application can realize more reliable PSCell selection because of the effective SINR estimation, so that the link failure probability on the PSCell after the auxiliary node is added is obviously reduced, and the phenomenon that the auxiliary node needs to be released soon after the auxiliary node is added, which is not expected, can be avoided.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the following detailed description of non-limiting embodiments thereof, made with reference to the accompanying drawings in which:

fig. 1 shows an architectural diagram of a dual connection between an NR MN and an NR SN of an SA deployed in Option 2(Option 2) in a 5G network;

fig. 2 shows an architecture diagram of dual connectivity between LTE MN and NR SN deploying NSA in Option 3(Option 3) in a 5G network;

fig. 3 illustrates a flow chart of a method for determining a PSCell by a master node in a dual connectivity system according to an aspect of the subject application;

FIG. 4 illustrates a schematic diagram of a master node determining a PSCell in a dual connectivity system, according to an aspect of the subject application;

fig. 5 is a schematic diagram illustrating transmission of SSB signals of a plurality of adjacent NR base stations in a scenario where an NR base station (i.e., a gNB) may serve as an auxiliary node of a dual connection in a 5G NR network according to an example of the present application;

fig. 6 is a schematic diagram illustrating a scenario in which an NR base station in a 5G NR network serves as a dual-connected auxiliary node according to an example of the present application, and SSB RSRP is used as a measurement indicator of a measurement reporting trigger event B1 in NSA deployment or a measurement reporting trigger event a4 in SA deployment.

The same or similar reference numbers in the drawings identify the same or similar elements.

Detailed Description

Generally, in a dual connectivity system, whether to select a candidate PSCell as a PSCell is determined according to whether a value of a parameter that can measure the quality of a channel condition, measured by a user equipment on the candidate PSCell, is greater than a predetermined threshold.

For any ue capable of dual connectivity, the theoretically best measurement parameter for measuring the channel condition of the candidate PSCell is SINR (Signal to Interference plus Noise Ratio). In NR 3GPP standard TS38.215, measurement indicators named "SS-SINR" and "CSI-SINR" are defined, SINR being measured by measuring signal power and interference power on the same set of Resource Elements (Resource Elements).

However, it has been discovered herein that although interference refers to unwanted signals that propagate on the same resource elements that carry the desired signals, in many cases, when transmission of reference signals (e.g., SSBs or CSI-RSs) is performed, the desired reference signals and the unwanted reference signals are intentionally configured for transmission over orthogonal resources (i.e., having orthogonality in the time domain, or frequency domain, or spatial domain, or code domain) to achieve clean reception and accurate detection of the desired reference signals.

In the above scenario, since the required reference signal and the undesired reference signal are transmitted through orthogonal resources, when the required reference signal is measured, the undesired reference signal cannot be measured (i.e. the interference signal cannot be measured), and therefore an effective estimate of SINR cannot be obtained, so that the "SS-SINR" or "CSI-SINR" defined in 3GPP TS38.215 cannot work normally. In other words, the estimated SINR will not really reflect how severe the interference is and how good/bad the radio channel conditions are, so that subsequent traffic transmissions (e.g. PDSCH transmissions) may experience severe interference. Therefore, currently, all operators and equipment in the industry directly adopt Reference Signal Receiving Power (RSRP) as a parameter for measuring the channel condition of the candidate PSCell when adding the auxiliary node (i.e., determining the PSCell) in the dual-connection working mode; of course, this is a second approach to fall back when no effective estimate of SINR can be obtained.

Furthermore, RSRQ (Reference Signal Receiving Quality) cannot be used as an effective estimate of SINR either, because the physical meaning of RSRQ, a parameter is: the ratio of "signal power" to "signal power + interference power + noise power". Indeed, according to the operation experience of 4G LTE networks, some mainstream telecom operators have explicitly shown that RSRQ does not provide a useful help for measuring the quality of channel conditions.

The radio transmission environment of a cellular mobile communication network is inherently limited by interference. Therefore, for a scenario where the required reference signals and the unnecessary reference signals are transmitted through orthogonal resources, it would be meaningful to design a simple and really useful criterion so that the PSCell can be determined with an effective SINR estimate when adding the auxiliary node.

The present application is described in further detail below with reference to the attached figures.

Before discussing exemplary embodiments in more detail, it should be noted that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although a flowchart may describe the operations as a sequential process, many of the operations can be performed in parallel, concurrently, or simultaneously. In addition, the order of the operations may be re-arranged. The process may be terminated when its operations are completed, but may have additional steps not included in the figure. The processes may correspond to methods, functions, procedures, subroutines, and the like.

The term "user equipment" as used herein may be considered synonymous with and sometimes hereinafter referred to as: client, mobile user, mobile terminal, subscriber, user, remote station, access terminal, receiver, mobile unit, etc., and may describe a remote user, remote UE, remote terminal, etc., of a wireless resource in a wireless communication network.

Similarly, the term "base station" as used herein may be considered synonymous with, and sometimes referred to hereinafter as: a node B, an evolved node B, an eNodeB, a gbnodeb, a Base Transceiver Station (BTS), a Radio Network Controller (RNC), etc., and may describe a transceiver that communicates with and provides radio resources for a mobile in a wireless communication network that may span multiple technology generations. The base stations discussed herein may have all of the functionality associated with conventional well-known base stations, except for the ability to implement the methods discussed herein.

Specific structural and functional details disclosed herein are merely representative and are provided for purposes of describing example embodiments of the present application. This application may, however, be embodied in many alternate forms and should not be construed as limited to only the embodiments set forth herein.

It should also be noted that, in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed substantially concurrently, or the figures may sometimes be executed in the reverse order, depending upon the functionality/acts involved.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Those skilled in the art will appreciate that the present application may be applicable to any communication system with dual connectivity mode of operation, for example, dual connectivity between LTE MN and LTE SN in LTE networks, or dual connectivity between MN and SN in SA deployment (i.e., option 2, option 5) or NSA deployment (i.e., option 3/3a/3X, option 4/4a, option 7/7a/7X) in 5G networks.

In one embodiment, in a dual-connectivity system as applied herein, desired reference signals and undesired reference signals (i.e., interference) are configured for transmission over orthogonal resources (i.e., having orthogonality in the time, or frequency, or spatial, or code domain).

The primary node is a base station device used as a primary node in the present application, including but not limited to LTE MN or NR MN in any of the above deployments.

Fig. 1 shows an architectural diagram of dual connectivity between NR MN and NR SN of an SA deployed in Option 2(Option 2) in a 5G network.

As the NR gNB of the MN is connected to an NGC (5G Core network), the MN needs to select one SgNB from a plurality of candidate sgnbs (i.e., candidate SgNB 1, candidate SgNB 2, candidate SgNB 3), that is, select a suitable PSCell from a plurality of candidate pscells. Wherein, SgNB is auxiliary gbb (secondary gbb).

Fig. 2 shows an architecture diagram of dual connectivity between LTE MN and NR SN with NSA deployed in Option 3(Option 3) in a 5G network.

The LTE eNB as the MN is connected to an EPC (Evolved Packet Core), and the MN also needs to select one SgNB from multiple candidate sgnbs (i.e., candidate SgNB 1, candidate SgNB 2, and candidate SgNB 3), that is, to select a suitable PSCell from multiple candidate pscells.

Fig. 1 and 2 show two typical scenarios applied in the present application as examples. Those skilled in the art will appreciate that other dual connection system architectures are equally suitable and encompassed within the scope of the present application.

Fig. 3 illustrates a flow chart of a method for determining a PSCell by a master node in a dual connectivity system according to an aspect of the subject application.

In step S1, the master node obtains RSRP measured by the user equipment on a to-be-detected carrier corresponding to the candidate PSCell in a sector to which the candidate PSCell belongs and one or more RSRPs measured by the user equipment on the same to-be-detected carrier in at least one adjacent sector of the sector, where the user equipment is a user equipment capable of dual connectivity.

In one embodiment, in step S1, the master node causes the user equipment to report RSRP measured on a to-be-detected carrier corresponding to the candidate PSCell in the sector and report one or more RSRPs measured on the same to-be-detected carrier in at least one neighboring sector of the sector, according to an event-triggered mechanism and/or a periodic reporting mechanism.

That is, if the master node detects that a predetermined measurement report trigger event is met according to an event trigger mechanism, the master node causes the ue to report RSRP measured on a to-be-detected carrier corresponding to the candidate PSCell in the sector and one or more RSRPs measured on the same to-be-detected carrier in at least one neighboring sector of the sector. In one embodiment, the measurement reporting trigger event for the event trigger mechanism comprises at least any one of a B1 event, a B2 event, and an a4 event.

Here, the B1 event is defined as a measurement value of a neighbor cell in an alien system using different radio access technologies being better than a threshold; the B2 event is defined as the measurement value of the serving cell being worse than one threshold and the measurement value of the neighbor cell in the heterogeneous system using different radio access technologies being better than another threshold; the a4 event is defined as the measurement of the neighbor cell being better than a threshold. In the present application, for dual connectivity in a 5G NR network, the B1 event is for NSA, the B2 event is for NSA, and the a4 event is for SA. It will be appreciated by those skilled in the art that other events that can be adapted to trigger a report are equally applicable to and within the scope of the present application.

Or, if the master node is according to a periodic reporting mechanism, periodically causing the user equipment to report RSRP measured on a to-be-detected carrier corresponding to the candidate PSCell in the sector and one or more RSRPs measured on the same to-be-detected carrier in at least one neighboring sector of the sector, based on a predetermined trigger period.

In one embodiment, the method further includes step S7 (not shown), in step S7, if the measurement time exceeds a predetermined time or the number of measurement reports exceeds a predetermined number, the master node releases the measurement report trigger event.

Here, when inter-frequency measurement needs to be performed, loss of available resources in the time domain may be caused by using dedicated measurement gaps in the time domain; in order to avoid that the loss of the time domain available resources reaches an unacceptable level, a dedicated timer may be set in the master node to monitor the measurement time, and if the measurement time of the dedicated timer exceeds a predetermined time, the master node releases the measurement reporting trigger event. The scenario for performing inter-frequency measurement is when different carrier frequencies are used between the primary node and the secondary node for dual connectivity, for example, NSA deployment in 5G, and the primary node and the secondary node when SA deployment in 5G use different carrier frequencies.

Or, the master node may define a predetermined number of measurement reports to be obtained, and if the number of RSRPs reported by the ue and obtained by the master node reaches the predetermined number, the master node releases the measurement report trigger event.

In step S2, the master node acquires AWGN average power corresponding to the user equipment.

The AWGN is Additive White Gaussian Noise (Additive White Gaussian Noise). The master node may estimate the AWGN average power itself or may cause the ue to report the AWGN average power.

For example, in one embodiment, the master node estimates the AWGN average power corresponding to the user equipment. For example, the estimated AWGN average power is noise power spectral density x operating bandwidth x noise figure, where the noise power spectral density may be predefined according to empirical values, the operating bandwidth is a given system parameter, and the noise figure may be defined according to different channel models.

For example, in one embodiment, the master node uses the AWGN average power reported by the user equipment from the measurements, i.e., the user equipment directly measures the AWGN average power and reports it to the master node.

In step S3, the master node takes RSRP measured by the user equipment on a to-be-detected carrier corresponding to the candidate PSCell in the sector to which the candidate PSCell belongs as a first parameter.

In step S4, the master node uses the sum of one or more RSRPs measured on the same to-be-detected carrier in the at least one neighboring sector and the AWGN average power as a second parameter.

In step S5, the master node estimates an SINR based on RSRP according to a ratio of the first parameter to the second parameter.

In step S6, if the estimated SINR based on RSRP is greater than a predetermined threshold, the candidate PSCell is taken as the PSCell of the user equipment. Thus, the user equipment can be simultaneously connected to the primary node and the secondary node to which the PSCell belongs to realize dual connectivity.

In one embodiment, the method further includes step S8 (not shown), in step S8, after the user equipment completes the determination of whether the candidate PSCell can be used as a PSCell, the master node releases and/or reconfigures a measurement reporting trigger event for the user equipment to report RSRP.

For example, after the ue completes the determination of whether the candidate PSCell can be used as a PSCell, the master node may release a measurement reporting trigger event that causes the ue to report RSRP; alternatively, for example, after the user equipment is connected to the secondary node to which the PSCell belongs, the primary node may reconfigure a measurement reporting trigger event for the user equipment to report RSRP.

In an embodiment, the method further includes step S9 (not shown), in step S9, when the ue needs to perform mobility-based handover, the main node releases the measurement reporting trigger event, and after the ue completes the mobility-based handover, the main node reconfigures the corresponding measurement reporting trigger event to the ue through a wireless interface.

Fig. 4 illustrates a schematic diagram of a master node for determining a PSCell in a dual connectivity system according to an aspect of the subject application.

The master node 10 includes a device 101, a device 102, a device 103, a device 104, a device 105, and a device 106.

The device 101 obtains RSRP measured by a user equipment on a to-be-detected carrier corresponding to a candidate PSCell in a sector to which the candidate PSCell belongs and one or more RSRPs measured by the user equipment on the same to-be-detected carrier in at least one adjacent sector of the sector, where the user equipment is a dual-connectable user equipment.

In one embodiment, the apparatus 101 causes the user equipment to report RSRP measured on a to-be-detected carrier corresponding to a candidate PSCell in the sector and report one or more RSRPs measured on the same to-be-detected carrier in at least one neighboring sector of the sector according to an event-triggered mechanism and/or a periodic reporting mechanism.

That is, if the device 101 detects that a predetermined measurement report trigger event is met according to an event trigger mechanism, it causes the ue to report RSRP measured on a to-be-detected carrier corresponding to the candidate PSCell in the sector and one or more RSRPs measured on the same to-be-detected carrier in at least one neighboring sector of the sector. In one embodiment, the measurement reporting trigger event for the event trigger mechanism comprises at least any one of a B1 event, a B2 event, and an a4 event. It will be appreciated by those skilled in the art that other events that can be adapted to trigger a report are equally applicable to and within the scope of the present application.

Or, if the device 101 is according to a periodic reporting mechanism, periodically cause the ue to report RSRP measured on a to-be-detected carrier corresponding to the candidate PSCell in the sector and one or more RSRPs measured on the same to-be-detected carrier in at least one neighboring sector of the sector, based on a predetermined trigger period.

In one embodiment, the master node 10 further comprises a device 107 (not shown), and the device 107 determines whether to release the measurement reporting trigger event according to whether the measurement time exceeds a predetermined time or the number of measurement reports exceeds a predetermined number, wherein the device 107 releases the measurement reporting trigger event if the measurement time exceeds the predetermined time or the number of measurement reports exceeds the predetermined number.

Here, when inter-frequency measurement needs to be performed, loss of available resources in the time domain may be caused by using dedicated measurement gaps in the time domain; in order to avoid that the loss of the available time domain resources reaches an unacceptable level, a dedicated timer may be arranged in the device 107 to monitor the measurement time, and if the measurement time of the dedicated timer exceeds a predetermined time period, the device 107 releases the measurement reporting trigger event. The scenario for performing inter-frequency measurement is when different carrier frequencies are used between the primary node and the secondary node for dual connectivity, for example, NSA deployment in 5G, and the primary node and the secondary node when SA deployment in 5G use different carrier frequencies.

Alternatively, the apparatus 107 may define a predetermined number of measurement reports to be acquired, and if the number of RSRPs reported by the ue and acquired by the apparatus 107 reaches the predetermined number, the apparatus 107 releases the measurement reporting trigger event.

The apparatus 102 obtains AWGN average power corresponding to the user equipment.

For example, in one embodiment, the apparatus 102 estimates an AWGN average power corresponding to the user equipment. For example, the estimated AWGN average power is noise power spectral density x operating bandwidth x noise figure, where the noise power spectral density may be predefined according to empirical values, the operating bandwidth is a given system parameter, and the noise figure may be defined according to different channel models.

For example, in one embodiment, the apparatus 102 employs the AWGN average power reported by the user equipment from the measurement, that is, the user equipment directly measures the AWGN average power and reports to the master node.

The device 103 uses RSRP measured by the user equipment on a to-be-detected carrier corresponding to the candidate PSCell in the sector to which the candidate PSCell belongs as a first parameter.

The device 104 uses the sum of one or more RSRPs measured on the same to-be-detected carrier on the at least one neighboring sector and the AWGN average power as the second parameter.

The apparatus 105 estimates an RSRP-based SINR as a function of a ratio of the first parameter to the second parameter.

The apparatus 106 determines whether to treat the candidate PSCell as a PSCell of the user equipment according to whether the estimated RSRP-based SINR is greater than a predetermined threshold; and if the estimated SINR based on the RSRP is larger than a preset threshold value, taking the candidate PSCell as the PSCell of the user equipment. Thus, the user equipment can be simultaneously connected to the primary node and the secondary node to which the PSCell belongs to realize dual connectivity.

In an embodiment, the master node 10 further comprises a device 108 (not shown), and after the user equipment completes the determination of whether the candidate PSCell can be used as a PSCell, the device 108 releases and/or reconfigures a measurement reporting trigger event for the user equipment to report RSRP.

For example, after the ue completes the determination of whether the candidate PSCell can be used as a PSCell, the device 108 may release a measurement reporting trigger event that causes the ue to report RSRP; alternatively, for example, after the user equipment is connected to the secondary node to which the PSCell belongs, the primary node may reconfigure a measurement reporting trigger event for the user equipment to report RSRP.

In an embodiment, the master node 10 further comprises a device 109 (not shown), when the ue needs to perform mobility based handover, the device 109 releases the measurement reporting trigger event, and after the ue completes the mobility based handover, the device 109 reconfigures the corresponding measurement reporting trigger event to the ue through a wireless interface.

The method of determining the PSCell by the master node in the dual connectivity system is explained below by a specific example in the 5G NR system.

Since the user equipment cannot configure dual connectivity when it is in idle (RRC idle) or inactive (RRC inactive) mode, it is in connected (RRC connected) mode when the PSCell is configured.

When the primary node determines the PSCell, the number of NR carriers is denoted as M (e.g., for NSA, M>1 is ═ 1; for SA, M>2) and denotes an index of the M NR carriers as c₁,c₂,…,c_M。

Generally, each NR base station (i.e., each gNB) configures at least one geographic sector, each sector being configured with M NR carriers.

For any one dually-connectable user equipment, the index of the sector to which the candidate NR PSCell of the user equipment belongs is represented as 0, and the index of the neighboring sector whose signal transmission can be detected by the user equipment is represented as 1, …, K. Here, for different user devices, the same sector index may correspond to different geographic sectors; in addition, the number of adjacent sectors (i.e., the value of K) may also be different for different user devices.

For any one dual-connectable user equipment, in sector 0, the indexes of M cells corresponding to M configured NR carriers are represented as (0, c)₁),(0,c₂),…,(0,c_M). Similarly, in neighboring sector K (K ∈ {1, …, K }), the index of the M cells corresponding to the M configured NR carriers is denoted as (K, c)₁),(k,c₂),…,(k,c_M)。

For any one dually connectable user equipment j, it is slave cell (k, c)_m) The measured RSRP (K ∈ {0,1, …, K }, M ∈ {1, …, M }) is expressed as

At the receiving end (i.e. user equipment for the downlink), the AWGN average power at a given operating bandwidth of the PSCell is denoted as P_noise[Watt]。

Generally, P is commonly used in engineering of real systems_noiseCan be estimated as P_noise＝P_{noise per Hz}X operating bandwidth x noise figure. Wherein the noise power spectral density P_{noise per Hz}＝10^-174[dBm]/10×10^-3[Watt per Hz]Bandwidth of operation [ Hz]Is a given system parameter, and for the ITU or 3GPP SCM channel model, the noise figure is 10^7[dB]/10Or 10^9[dB]/10. For simplicity, P may be substituted_noiseAs different user equipmentA unified representation of the AWGN average power at (a).

Or, P_noiseMeasurements may be made by the user equipment (i.e., the equipment on the receiving end of the downlink) and reported to the primary node. Likewise, for simplicity, P measured for different user equipments is no longer measured_noiseA distinction is made.

Defining a predetermined threshold as the target SINR, i.e. SINR_{target,RSRP-based for PSCell}[dB]If the estimated SINR based on RSRP is greater than the predetermined threshold, the master node takes the candidate PSCell as the PSCell of the user equipment.

In summary, for any dually-connectable user equipment j, in the currently detected sector, the index of the cell corresponding to the currently detected carrier (i.e. the currently detected candidate PSCell) is represented as (0, c)_i) Where i ∈ {1, …, M }. Then, in a neighboring sector K (K ∈ {1, …, K }) of the currently detected sector, the cell index corresponding to the currently detected carrier is represented as (K, c)_i)。

In order to effectively estimate the SINR when the required reference signal and the unnecessary reference signal (i.e., interference) are transmitted through orthogonal resources, the RSRP-based SINR estimated by the following formula (1) is used as a criterion for determining the PSCell from the candidate pscells:

i.e. if the estimated RSRP-based SINR:

if equation (1) is satisfied, the master node takes the candidate PSCell as the PSCell of the user equipment.

Fig. 5 shows a transmission diagram of SSB signals of a plurality of adjacent NR base stations in a scenario that an NR base station (i.e., a gNB) may serve as an auxiliary node of a dual connection in a 5G NR network according to an example of the present application.

Wherein the Cell ID (i.e., Cell ID) is (0, c)₁) Denoted in sector 0, with the configured NR carrier c₁An index of a corresponding cell, where a sector 0 indicates that the sector is a sector to which a currently detected candidate NR PSCell of the user equipment belongs; cell ID (i.e., Cell ID) is (1, c)₁)，(2,c₁)，(3,c₁) Means that in the

sectors

1, 2, 3 adjacent to the currently detected sector, there is a NR carrier c allocated thereto₁The index of the corresponding cell, wherein

sectors

1, 2, 3 represent the sectors that are neighbors of the sector to which the currently detected candidate NR PSCell of the user equipment belongs.

As can be seen from fig. 5, in order for the ue in each cell to obtain clean reception and accurate detection of the 1 st SSB transmitted by its serving gNB, the 1 st SSB signals of these neighboring cells are transmitted through orthogonal resources. In fig. 5, the orthogonality of the transmission resources is done in the time domain. Those skilled in the art will appreciate that in a real network deployment, the orthogonality of the transmission resources may also be accomplished in the frequency domain, or in the spatial domain, or in the code domain.

In fig. 6, user equipment j measures the SSB RSRP and reports the measured SSB RSRP to the master node. Measured to obtain

Denotes the user equipment j slave cell (0, c)₁) The RSRP of the result of the measurement,

denotes the user equipment j slave cell (1, c)₁) The RSRP of the result of the measurement,

denotes the user equipment j slave cell (2, c)₁) The RSRP of the result of the measurement,

denotes the user equipment j slave cell (3, c)₁) The measured RSRP. Wherein, cell IDs (0, c)₁),(1,c₁)，(2,c₁)，(3,c₁) The meaning of (1) and the cell IDs (0, c) in the description of fig. 5₁),(1,c₁)，(2,c₁)，(3,c₁) Have the same meaning.

Then, the master node estimates an RSRP-based SINR using formula (1), and determines a PSCell from the candidate pscells based on the estimated RSRP-based SINR.

Here, in order to allow the ue to report all detectable RSRPs on the carrier corresponding to the currently detected candidate PSCell to the master node, the master node may perform configuration for measurement reporting on the ue through a wireless interface.

Here, the configuration pattern of the corresponding reference signal (e.g. the configuration pattern of the SSB signal in the time domain) may be exchanged between the neighboring cells through the X2 interface, so that the master node performs the correct calculation according to the method proposed in the present application.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

It should be noted that the present application may be implemented in software and/or a combination of software and hardware, for example, implemented using Application Specific Integrated Circuits (ASICs), general purpose computers or any other similar hardware devices. In one embodiment, the software programs of the present application may be executed by a processor to implement the steps or functions described above. Likewise, the software programs (including associated data structures) of the present application may be stored in a computer readable recording medium, such as RAM memory, magnetic or optical drive or diskette and the like. Additionally, some of the steps or functions of the present application may be implemented in hardware, for example, as circuitry that cooperates with the processor to perform various steps or functions.

In addition, some of the present application may be implemented as a computer program product, such as computer program instructions, which when executed by a computer, may invoke or provide methods and/or techniques in accordance with the present application through the operation of the computer. Those skilled in the art will appreciate that the form in which the computer program instructions reside on a computer-readable medium includes, but is not limited to, source files, executable files, installation package files, and the like, and that the manner in which the computer program instructions are executed by a computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Computer-readable media herein can be any available computer-readable storage media or communication media that can be accessed by a computer.

Communication media includes media by which communication signals, including, for example, computer readable instructions, data structures, program modules, or other data, are transmitted from one system to another. Communication media may include conductive transmission media such as cables and wires (e.g., fiber optics, coaxial, etc.) and wireless (non-conductive transmission) media capable of propagating energy waves such as acoustic, electromagnetic, RF, microwave, and infrared. Computer readable instructions, data structures, program modules, or other data may be embodied in a modulated data signal, for example, in a wireless medium such as a carrier wave or similar mechanism such as is embodied as part of spread spectrum techniques. The term "modulated data signal" means a signal that has one or more of its characteristics set or changed in such a manner as to encode information in the signal. The modulation may be analog, digital or hybrid modulation techniques.

By way of example, and not limitation, computer-readable storage media may include volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer-readable instructions, data structures, program modules or other data. For example, computer-readable storage media include, but are not limited to, volatile memory such as random access memory (RAM, DRAM, SRAM); and non-volatile memory such as flash memory, various read-only memories (ROM, PROM, EPROM, EEPROM), magnetic and ferromagnetic/ferroelectric memories (MRAM, FeRAM); and magnetic and optical storage devices (hard disk, tape, CD, DVD); or other now known media or later developed that can store computer-readable information/data for use by a computer system.

An embodiment according to the present application comprises an apparatus comprising a memory for storing computer program instructions and a processor for executing the program instructions, wherein the computer program instructions, when executed by the processor, trigger the apparatus to perform a method and/or a solution according to the aforementioned embodiments of the present application.

It will be evident to those skilled in the art that the present application is not limited to the details of the foregoing illustrative embodiments, and that the present application may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned. Furthermore, it is obvious that the word "comprising" does not exclude other elements or steps, and the singular does not exclude the plural. A plurality of units or means recited in the apparatus claims may also be implemented by one unit or means in software or hardware. The terms first, second, etc. are used to denote names, but not any particular order.

Claims

1. A method for determining a PSCell by a master node in a dual connectivity system, wherein the method comprises the steps of:

acquiring AWGN average power corresponding to the user equipment;

2. The method of claim 1, wherein obtaining the AWGN average power corresponding to the user equipment comprises:

estimating the AWGN average power corresponding to the user equipment; and/or

3. The method according to claim 1 or 2, wherein the step of obtaining the RSRP measured by the user equipment on the to-be-detected carrier corresponding to the candidate PSCell in the sector to which the candidate PSCell belongs and the RSRP measured by the user equipment on the same to-be-detected carrier on at least one neighboring sector of the sector comprises:

4. The method of claim 3, wherein a measurement reporting trigger event for the event trigger mechanism comprises at least any one of a B1 event, a B2 event, and an A4 event.

5. The method of claim 3 or 4, wherein the method further comprises:

6. The method of claim 3 or 4, wherein the method further comprises:

7. The method of claim 3 or 4, wherein the method further comprises:

8. A master node for determining a PSCell in a dual connectivity system, wherein the master node comprises:

means for obtaining AWGN average power corresponding to the user equipment;

9. The master node of claim 8, wherein the means for obtaining the AWGN average power corresponding to the user equipment is configured to:

estimating the AWGN average power corresponding to the user equipment; and/or

10. The master node of claim 8 or 9, wherein the means for obtaining the RSRP measured by the user equipment on the to-be-detected carrier corresponding to the candidate PSCell in the sector to which the candidate PSCell belongs and the one or more RSRPs measured by the user equipment on the same to-be-detected carrier in at least one neighboring sector of the sector is configured to:

11. The master node of claim 10, wherein a measurement reporting trigger event for the event trigger mechanism comprises at least any one of a B1 event, a B2 event, an a4 event.

12. The master node of claim 10 or 11, wherein the master node further comprises:

13. The master node of claim 10 or 11, wherein the master node further comprises:

14. The master node of claim 10 or 11, wherein the master node further comprises:

15. A system for determining a PSCell by a master node in a dual-connectivity system, comprising one or more user devices, one or more secondary nodes, and one or more master nodes that determine a PSCell in a dual-connectivity system, wherein the master nodes comprise:

means for obtaining AWGN average power corresponding to the user equipment;

16. A computer-readable storage medium having stored thereon computer instructions that cause an apparatus to at least perform:

acquiring AWGN average power corresponding to the user equipment;

17. An apparatus, the apparatus comprising:

at least one processor; and

at least one memory having a computer program stored thereon;

acquiring AWGN average power corresponding to the user equipment;