Patent Description:
For network optimization of a present mobile communication system, a drive test is usually used to check whether the coverage quality and the system performance achieve desired design requirements. In a conventional drive test, professional people, e.g. network optimizers, drive vehicles along random routes. Each of them uses a measurement terminal to record events and measurement values along the route, and provides the records to the operator for network optimization. This process requires significant labor and time, which imposes a heavy burden for the network operator to build and maintain the network.

In order to reduce the cost and complexity of a manual drive test, the Third Generation Partnership Projects (3GPP) introduces a Minimization of Drive Test (MDT) function in Universal Terrestrial Radio Access Network (UTRAN) and Evolved UTRAN (E-UTRAN) release-<NUM> version. The UTRAN includes base station Node B and radio network controller (RNC). The E-UTRAN includes evolved base station eNB. The core network (CN) corresponding to the UTRAN includes a Home Subscriber Server (HSS), a Mobile Switching Center (MSC) server, a serving GPRS (general packet radio service) support node (SGSN), etc. The CN corresponding to the E-UTRAN includes an HSS, a Mobile Management Entity (MME), etc. The MDT function automatically collects measurement information by a user equipment (UE) or a terminal, and reports the measurement information to a radio access network (RAN) through a control plane signaling. For a UTRAN system, the measurement information is reported to an RNC; for an E-UTRAN system, the measurement information is reported to an eNB. Then the measurement information is reported to a.

Trace Collection Entity (TCE) of an Operation and Maintenance (OAM) system through the RAN for network optimization, e.g. for discovering and solving the network coverage issue.

In addition, the MDT function can be used to collect wireless measurement information in areas, e.g. indoor areas and private areas, where a manual drive test cannot reach. But existing technology on MDT focuses merely on a drive test in a wireless network under a single-connectivity architecture, where a terminal connects merely to a single base station for service. Thus, existing systems and methods for configuring MDT in a wireless network are not entirely satisfactory.

<CIT> relates to a method that comprises receiving, by a first network node, a minimization-of-drive-test activation command, performing collection of a first minimization-of-drive-test data, and instructing a second network node to at least one of collect and report a second minimization-of-drive-test data.

The exemplary embodiments disclosed herein are directed to solving the issues relating to one or more of the problems presented in the prior art, as well as providing additional features that will become readily apparent by reference to the following detailed description when taken in conjunction with the accompany drawings. In accordance with various embodiments, exemplary systems, methods, devices and computer program products are disclosed herein. It is understood, however, that these embodiments are presented by way of example and not limitation, and it will be apparent to those of ordinary skill in the art who read the present disclosure that various modifications to the disclosed embodiments can be made while remaining within the scope of the present disclosure.

Various exemplary embodiments of the present disclosure are described below with reference to the accompanying figures to enable a person of ordinary skill in the art to make and use the present disclosure. As would be apparent to those of ordinary skill in the art, after reading the present disclosure, various changes or modifications to the examples described herein can be made without departing from the scope of the present disclosure.

Multi-connectivity architecture and minimization of drive test are important features in mobile communication systems. A typical wireless communication network includes one or more base stations (typically known as a "BS") that each provides a geographical radio coverage (a cell), and one or more wireless user equipment devices (typically known as a "UE") that can transmit and receive data within the radio coverage. Under a multi-connectivity architecture, a plurality of micro cell clusters may be distributed in a macro cell. A terminal may maintain a data connection with one or more micro cells while maintaining a data connection with the macro cell. That is, under a multi-connectivity architecture, a terminal can connect to multiple access-side network elements, e.g. multiple base stations, to obtain services. A minimization of drive test (MDT) function enables network operators to automatically obtain measurement data and optimize the network based on the measurement data.

The present disclosure provides methods for configuring an MDT measurement in a multi-connectivity architecture. Each network element (NE) participating in the MDT can independently determine how to trigger the measurement. A telecommunications network at the physical layer includes many interconnected wireline NEs. These NEs can be stand-alone systems or products that are either supplied by a single manufacturer or are assembled by the service provider with parts from several different manufacturers. In a wireless network, an NE is a node, a base station, or any product used by a wireless carrier to provide support for the backhaul network as well as a mobile switching center. Under a multi-connectivity architecture, an NE may be a master node (MN) or a secondary node (SN). In one embodiment, a first wireless communication node transmits configuration information for a MDT measurement to a second wireless communication node; and receives, from the second wireless communication node, a feedback in response to the configuration information for the MDT measurement. The two wireless communication nodes may be two nodes, e.g. two network elements MN and SN, of a same wireless network with a multi-connectivity architecture.

In addition to configuring the measurement at an NE itself, each NE can also allocate part of the MDT measurement to other NEs. For example, an MN may allocate the base station side measurement configuration of the MDT to the MN base station to implement, give the terminal side measurement to the terminal through a control plane of the SN, and give the positioning measurement configuration to the SN base station. After the MDT measurement is completed, the SN collects the measurement results of the terminal and the SN base station and reports the measurement results to the MN according to the configuration information, or collects the measurement results of the terminal and the SN base station according to the configuration and reports the measurement results to the TCE device. The configuration information for the MDT measurement comprises information related to at least one of: measurement objects of the MDT measurement; measured values of the MDT measurement; a location measurement manner; link direction of the MDT measurement; a location measurement provider; trace collection entity device information; operator information; one or more MDT measurement collection locations; one or more network elements that report the MDT measurement result; measurement type of the MDT measurement; base station information that triggers the MDT measurement; and network management information of the base station that triggers the MDT measurement.

The feedback, in response to the configuration information for the MDT measurement, may comprise a confirmation of the configuration information for the MDT measurement, or a conflict indication indicating that the second wireless communication node has triggered an existing MDT measurement, which is the same as the MDT measurement, on a same wireless communication device or terminal. A conflict may happen when multiple NEs respectively perform a same type of MDT measurement for a same UE. For example, an MN triggers a signaling-based MDT measurement on a certain terminal, while at the same time the network management of the SN base station triggers a management-based MDT on the terminal. As such, the MN and the SN select the same measurement on the same terminal. The disclosed method solves this conflict through a negotiation or a predetermined agreement between the two base stations MN and SN.

In an exemplary method to avoid a conflict between two nodes, a first wireless communication node transmits a request for an MDT measurement to a second wireless communication node; receives a configuration message for the MDT measurement from the second wireless communication node; and transmits a feedback in response to the configuration message to the second wireless communication node. The two wireless communication nodes may be two nodes, e.g. two network elements MN and SN, of a same wireless network with a multi-connectivity architecture. The request may comprise a first measurement configuration for the MDT desired by the first node; while the configuration message transmitted by the second node may comprise a second measurement configuration that is same as or different from the first measurement configuration, depending on whether there is an MDT conflict between the two nodes, i.e. whether the second node has triggered or desires another MDT measurement to be executed on a same terminal as the MDT measurement desired by the first node.

In various embodiments, a BS in the present disclosure can be referred to as a network side and can include, or be implemented as, a next Generation Node B (gNB), an E-UTRAN Node B (eNB), a Transmission/Reception Point (TRP), an Access Point (AP), a network element (NE), etc.; while a UE in the present disclosure can be referred to as a terminal and can include, or be implemented as, a mobile station (MS), a station (STA), etc. Under a multi-connectivity architecture, an NE may be a master node (MN) or a secondary node (SN). A BS and a UE may be described herein as non-limiting examples of "wireless communication nodes," and "wireless communication devices" respectively, which can practice the disclosed methods and may be capable of wireless and/or wired communications, in accordance with various embodiments of the present disclosure.

<FIG> illustrates an exemplary communication network <NUM> in which techniques disclosed herein may be implemented, in accordance with an embodiment of the present disclosure. In one embodiment, the exemplary communication network <NUM> has a Fifth Generation (<NUM>) architecture, which includes a <NUM> core network (5GC) <NUM> portion and a next generation radio access network (NG-RAN) <NUM> portion. As shown in <FIG>, the 5GC portion <NUM> includes mobility management function (AMF) and user plane function (UPF) <NUM>, <NUM>; while the NG-RAN portion <NUM> includes gNBs <NUM>, <NUM> and/or ng-eNBs <NUM>, <NUM>. The interfaces between the <NUM> access network <NUM> and the <NUM> core network <NUM> are NG interfaces <NUM>. The gNBs <NUM>, <NUM> and ng-eNBs <NUM>, <NUM> may communicate via inter-base station control plane interfaces such as an Xn interface <NUM> or an X2 interface.

<FIG> illustrates an exemplary wireless network <NUM> with a multi-connectivity architecture in which techniques disclosed herein may be implemented, in accordance with an embodiment of the present disclosure. With the deployment of networks and the enhancement of terminal capabilities, a terminal can be connected to multiple base stations for service. As shown in <FIG>, a plurality of micro or small cell clusters <NUM>, <NUM>, <NUM> are distributed in a macro cell <NUM><NUM>; while a plurality of micro or small cell clusters <NUM>, <NUM>, <NUM> are distributed in a macro cell <NUM><NUM>. A terminal may maintain a data connection with one or more micro cells while maintaining a data connection with a macro cell. This architecture is called a multi-connectivity architecture.

Dual connectivity (DC) has been standardized to enable a UE to establish two simultaneous and independent radio link (RL) connections with the master base station (Mng-eNB/gNB) and the secondary base station (Sng-eNB/gNB) respectively. The UE may be configured with a master cell group (MCG) bearer, a secondary cell group (SCG) bearer, or a split bearer. In one embodiment, the split bearer supports only the downlink data offload. In this case, the UE may simultaneously obtain DRB (Data Radio Bearer) services provided by two inter-frequency non co-site base station radio resources. The enhanced dual connectivity (eDC) is further standardized to allow the UE to establish two independent RL connections with the Mng-eNB/gNB and the Sng-eNB/gNB at the same time. The UE can further configure a split bearer to complement the uplink offload. In this case, the UE can simultaneously obtain the DRB services provided by two inter-frequency non co-site base station radio resources. Support can be given to a certain mobility scenario, e.g., switching between different Mng-eNBs/gNBs while keeping the Sng-eNB/gNB connections unchanged.

An MDT measurement may be configured under the multi-connectivity architecture shown in <FIG>. An MDT function enables network operators to automatically obtain measurement data and optimize the network based on the measurement data. The MDT function may be divided into a management-based MDT and a signaling-based MDT. Taking the E-UTRAN system as an example, the activation process of the management-based MDT usually includes that: an OAM transmits a trace session activation message including the MDT configuration to the eNB; the eNB selects a suitable UE within the area specified by the message and transmits the MDT configuration information to the selected UE. The activation process of the signaling-based MDT includes that: the OAM transmits a trace session activation message including an MDT configuration to an HSS to activate MDT measurement of a designated UE; the HSS transmits the MDT configuration information of the UE to the MME; and the MME transmits the MDT configuration information of the UE to the eNB; and finally the eNB transmits the MDT configuration information to the UE. The signaling-based MDT usually designates a certain UE with an International Mobile Subscriber Identity (IMSI) or an International Mobile Equipment Identity (IMEI), or adds area information to restrict the UE selection. The activation message of the management-based MDT and the signaling-based MDT includes trace reference information from the OAM, including public land mobile network (PLMN) information, which includes mobile country code and mobile network code.

<FIG> illustrates a block diagram of a master node (MN) <NUM>, in accordance with some embodiments of the present disclosure. The MN <NUM> is an example of a node that can be configured to implement the various methods described herein. As shown in <FIG>, the MN <NUM> includes a housing <NUM> containing a system clock <NUM>, a processor <NUM>, a memory <NUM>, a transceiver <NUM> comprising a transmitter <NUM> and receiver <NUM>, a power module <NUM>, an MDT measurement configurator <NUM>, a feedback analyzer <NUM>, an MDT measurement executor <NUM>, an MDT result reporter <NUM>, a configuration message analyzer <NUM>, and a feedback generator <NUM>.

In this embodiment, the system clock <NUM> provides the timing signals to the processor <NUM> for controlling the timing of all operations of the MN <NUM>. The processor <NUM> controls the general operation of the MN <NUM> and can include one or more processing circuits or modules such as a central processing unit (CPU) and/or any combination of general-purpose microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate array (FPGAs), programmable logic devices (PLDs), controllers, state machines, gated logic, discrete hardware components, dedicated hardware finite state machines, or any other suitable circuits, devices and/or structures that can perform calculations or other manipulations of data.

The transceiver <NUM>, which includes the transmitter <NUM> and receiver <NUM>, allows the MN <NUM> to transmit and receive data to and from a remote device (e.g., the BS or another UE). An antenna <NUM> is typically attached to the housing <NUM> and electrically coupled to the transceiver <NUM>. In various embodiments, the MN <NUM> includes (not shown) multiple transmitters, multiple receivers, and multiple transceivers. In one embodiment, the antenna <NUM> is replaced with a multi-antenna array <NUM> that can form a plurality of beams each of which points in a distinct direction. The transmitter <NUM> can be configured to wirelessly transmit packets having different packet types or functions, such packets being generated by the processor <NUM>. Similarly, the receiver <NUM> is configured to receive packets having different packet types or functions, and the processor <NUM> is configured to process packets of a plurality of different packet types. For example, the processor <NUM> can be configured to determine the type of packet and to process the packet and/or fields of the packet accordingly.

In a wireless network with a multi-connectivity architecture, the MN <NUM> may configure an MDT measurement alone or with an SN in the wireless network. For example, the MDT measurement configurator <NUM> may generate configuration information for an MDT measurement and transmit, via the transmitter <NUM>, the configuration information to another wireless communication node, e.g. an SN. The MN <NUM> and the SN are both nodes in the wireless network. In one embodiment, the MDT measurement is to be executed by a wireless communication device, e.g. a terminal or a UE, in the wireless network. In another embodiment, the MDT measurement comprises a first portion to be executed by the MN <NUM>, a second portion to be executed by the SN, and a third portion to be executed by a terminal in the wireless network. In this case, the MDT measurement configurator <NUM> may merely transmit the second portion to the SN; or transmit both the second portion and the third portion to the SN, where the SN can forward the third portion to the terminal. The configuration information for the MDT measurement comprises information related to at least one of: measurement objects of the MDT measurement; measured values of the MDT measurement; a location measurement manner; link direction of the MDT measurement; a location measurement provider; trace collection entity device information; operator information; one or more MDT measurement collection locations; one or more network elements that report the MDT measurement result; measurement type of the MDT measurement; base station information that triggers the MDT measurement; and network management information of the base station that triggers the MDT measurement.

In one embodiment, to avoid an MDT conflict between the MN <NUM> and the SN, the MDT measurement configurator <NUM> can first transmit a request for the MDT measurement to the SN. The request comprises configuration information for the MDT measurement to notify the SN that the MN <NUM> desires to trigger the MDT measurement according to the configuration information. The MDT measurement configurator <NUM> may inform the feedback analyzer <NUM> that a request or a configuration message has been sent to and a feedback is expected from the SN.

The feedback analyzer <NUM> in this example may receive, via the receiver <NUM> from the SN, a feedback in response to the configuration information for the MDT measurement. The feedback analyzer <NUM> analyzes the feedback to determine whether the feedback comprises a confirmation of the configuration information for the MDT measurement, or the feedback comprises a conflict indication indicating that the SN has triggered an existing MDT measurement, which is same as the MDT measurement, on the same terminal. In case the feedback comprises a confirmation of the configuration information for the MDT measurement, the feedback analyzer <NUM> may inform the MDT measurement executor <NUM> to execute the MDT measurement, e.g. via itself and the terminal, by sending an instruction to the MDT measurement executor <NUM>. In case the feedback comprises a conflict indication indicating that the SN has triggered an existing MDT measurement same as the MDT measurement on the same terminal, the feedback analyzer <NUM> may inform the MDT measurement executor <NUM> to stop executing or not to execute the MDT measurement, by sending an instruction to the MDT measurement executor <NUM>.

The MDT measurement executor <NUM> in this example may execute or stop executing the MDT measurement based on an instruction received from the feedback analyzer <NUM>. In one embodiment, the MDT measurement executor <NUM> executes the MDT measurement based on the configuration information via a terminal in the wireless network, after receiving an instruction from the feedback analyzer <NUM> that indicates that a confirmation of the configuration information has been received from the SN. In another embodiment, the MDT measurement executor <NUM> stops the MDT measurement after receiving an instruction from the feedback analyzer <NUM> that indicates that a conflict indication has been received from the SN. When the MDT measurement includes different portions, the MDT measurement executor <NUM> may execute a first portion by itself, instruct the SN to execute a second portion, and instruct the terminal to execute a third portion. After the execution, the MDT measurement executor <NUM> may send the measurement result to the MDT result reporter <NUM> for reporting.

The MDT result reporter <NUM> in this example may receive the measurement result from the MDT measurement executor <NUM> and report it to the network management, e.g. a trace collection entity (TCE) device, of the wireless network. In one embodiment, the MDT result reporter <NUM> receives a first measurement result generated by the MDT measurement executor <NUM> that executes a first portion of the MDT measurement, and reports the first measurement result to the TCE of the wireless network. In another embodiment, the MDT result reporter <NUM> receives a second measurement result from the SN that executes a second portion of the MDT measurement to generate the second measurement result, and reports the second measurement result to the TCE of the wireless network. In yet another embodiment, the MDT result reporter <NUM> may also collect a third measurement result from the terminal that executes a third portion of the MDT measurement to generate the third measurement result, and reports the third measurement result to the TCE of the wireless network.

The configuration message analyzer <NUM> in this example may receive, via the receiver <NUM>, a configuration message from the SN, and analyze the configuration message. For example, the configuration message comprises second configuration information for a second MDT measurement desired by the SN, where the second MDT measurement is same as the MDT measurement desired by the MN <NUM> and is to be executed on the same terminal in the wireless network. In one embodiment, the configuration message analyzer <NUM> may instruct the feedback generator <NUM> to generate a feedback to indicate an MDT conflict and ask the SN to stop the second MDT measurement. In another embodiment, the configuration message analyzer <NUM> may instruct the MDT measurement executor <NUM> to stop executing the MDT measurement desired by the MN <NUM>, and instruct the feedback generator <NUM> to generate a feedback to instruct the SN to continue the second MDT measurement.

In one embodiment, after the MDT measurement configurator <NUM> transmits, via the receiver <NUM>, the request for the MDT measurement to the SN to indicate the desire of the MN <NUM> to trigger the MDT measurement according to the configuration information, the configuration message analyzer <NUM> may receive a configuration message for the MDT measurement from the SN. While the request comprises first configuration information for the MDT measurement, the configuration message comprises second configuration information for the MDT measurement. The second configuration information may be the same as or different from the first configuration information. That is, the SN may either agree with or disagree with the MDT configuration desired by the MN <NUM>. Based on the analysis result of the configuration message, the configuration message analyzer <NUM> may instruct the feedback generator <NUM> to generate a feedback.

The feedback generator <NUM> in this example may generate a feedback, in response to a request or configuration message from another node, and transmit, via the transmitter <NUM>, the feedback to the node, e.g. the SN. In one embodiment, after the MN <NUM> receives second configuration information for a second MDT measurement desired by the SN, where the second MDT measurement is same as the MDT measurement desired by the MN <NUM> and is to be executed on the same terminal in the wireless network, the feedback generator <NUM> may transmit to the SN a feedback including a conflict indication in response to the second configuration information. The conflict indication indicates a conflict between the MDT measurement and the second MDT measurement to stop the second MDT measurement at the SN.

In another embodiment, after the MN <NUM> receives second configuration information for a second MDT measurement desired by the SN, where the second MDT measurement is same as the MDT measurement desired by the MN <NUM> and is to be executed on the same terminal in the wireless network, the feedback generator <NUM> may transmit to the SN a feedback including a confirmation of the second configuration information for the second MDT measurement to instruct the SN to continue the second MDT measurement.

In yet another embodiment, after the configuration message analyzer <NUM> receives the configuration message including second configuration information that may be the same as or different from the first configuration information, the feedback generator <NUM> transmits, via the transmitter <NUM> to the SN, a feedback in response to the configuration message. In one example, the second configuration information is the same as the first configuration information; and the feedback comprises a confirmation that the MDT measurement is to be executed based on the first configuration information, i.e. based on the second configuration information. In another example, the second configuration information is different from the first configuration information; and the feedback comprises a confirmation that the MDT measurement is to be executed based on the second configuration information.

The power module <NUM> can include a power source such as one or more batteries, and a power regulator, to provide regulated power to each of the above-described modules in <FIG>. In some embodiments, if the MN <NUM> is coupled to a dedicated external power source (e.g., a wall electrical outlet), the power module <NUM> can include a transformer and a power regulator.

The various modules discussed above are coupled together by a bus system <NUM>. The bus system <NUM> can include a data bus and, for example, a power bus, a control signal bus, and/or a status signal bus in addition to the data bus. It is understood that the modules of the MN <NUM> can be operatively coupled to one another using any suitable techniques and mediums.

Although a number of separate modules or components are illustrated in <FIG>, persons of ordinary skill in the art will understand that one or more of the modules can be combined or commonly implemented. For example, the processor <NUM> can implement not only the functionality described above with respect to the processor <NUM>, but also implement the functionality described above with respect to the feedback analyzer <NUM>. Conversely, each of the modules illustrated in <FIG> can be implemented using a plurality of separate components or elements.

<FIG> illustrates a flow chart for a method <NUM> performed by an MN, e.g. the MN <NUM> in <FIG>, for configuring MDT under a multi-connectivity architecture, in accordance with some embodiments of the present disclosure. At operation <NUM>, the MN transmits a request for an MDT measurement to an SN in a same wireless network under a multi-connectivity architecture. The MN receives at operation <NUM> a configuration message for the MDT measurement from the SN. The MN determines at operation <NUM> whether there is an MDT conflict between the MN and the SN. At operation <NUM>, the MN transmits a feedback in response to the configuration message to the SN. Then the MN executes at operation <NUM> at least a portion of the MDT measurement with a help of a terminal.

<FIG> illustrates a block diagram of an SN <NUM>, in accordance with some embodiments of the present disclosure. The SN <NUM> is an example of a node that can be configured to implement the various methods described herein. As shown in <FIG>, the SN <NUM> includes a housing <NUM> containing a system clock <NUM>, a processor <NUM>, a memory <NUM>, a transceiver <NUM> comprising a transmitter <NUM> and a receiver <NUM>, a power module <NUM>, an MDT measurement configurator <NUM>, a feedback analyzer <NUM>, an MDT measurement executor <NUM>, an MDT result reporter <NUM>, a configuration message analyzer <NUM>, and a feedback generator <NUM>.

In this embodiment, the system clock <NUM>, the processor <NUM>, the memory <NUM>, the transceiver <NUM> and the power module <NUM> work similarly to the system clock <NUM>, the processor <NUM>, the memory <NUM>, the transceiver <NUM> and the power module <NUM> in the MN <NUM>. An antenna <NUM> or a multi-antenna array <NUM> is typically attached to the housing <NUM> and electrically coupled to the transceiver <NUM>.

In one embodiment, the MDT measurement configurator <NUM> may work similarly to the MDT measurement configurator <NUM> in the MN <NUM>, by proactively transmitting configuration information for an MDT measurement. In another embodiment, after or at the same time as the MDT measurement configurator <NUM> transmits to the SN <NUM> first configuration information for a first MDT measurement desired by the MN <NUM> on a terminal in the wireless network, the MDT measurement configurator <NUM> generates and transmits to the MN <NUM> second configuration information for a second MDT measurement desired by the SN <NUM>. The two MDT measurements are the same and to be executed on the same terminal. In yet another embodiment, in response to a request from the MN <NUM> for an MDT measurement, the MDT measurement configurator <NUM> may generate and transmit to the MN <NUM> a configuration message for the MDT measurement. While the request comprises first configuration information for the MDT measurement, the configuration message comprises second configuration information for the MDT measurement. The second configuration information is the same as or different from the first configuration information.

In one embodiment, the feedback analyzer <NUM> may work similarly to the feedback analyzer <NUM> in the MN <NUM>. In another embodiment, after the MDT measurement configurator <NUM> transmits to the MN <NUM> the second configuration information for the second MDT measurement, the feedback analyzer <NUM> receives, via the receiver <NUM> from the MN <NUM>, a feedback in response to the second configuration information. The feedback may comprise either a conflict indication indicating a conflict between the MDT measurement desired by the MN <NUM> and the second MDT measurement desired by the SN <NUM> to stop the second MDT measurement, or a confirmation of the second configuration information to instruct continuation of the second MDT measurement. In yet another embodiment, after the MDT measurement configurator <NUM> transmits to the MN <NUM> the configuration message for the MDT measurement, the feedback analyzer <NUM> receives, via the receiver <NUM> from the MN <NUM>, a feedback in response to the configuration message. The feedback comprises a confirmation that the MDT measurement is to be executed by the MN <NUM> based on either the first configuration information or the second configuration information.

In one embodiment, the MDT measurement executor <NUM> may work similarly to the MDT measurement executor <NUM> in the MN <NUM>. In another embodiment, the MDT measurement executor <NUM> may execute a portion of the MDT measurement triggered by the MN <NUM>. In yet another embodiment, due to an MDT conflict between the MN <NUM> and the SN <NUM>, the MDT measurement executor <NUM> may stop the second MDT measurement desired by the SN <NUM>. In still another embodiment, despite an MDT conflict between the MN <NUM> and the SN <NUM>, the MDT measurement executor <NUM> executes the second MDT measurement desired by the SN <NUM> in response to a confirmation from the MN <NUM>. The MDT measurement executor <NUM> may send the MDT measurement result to the MDT result reporter <NUM> or to the MN <NUM> for reporting.

In one embodiment, the MDT result reporter <NUM> may work similarly to the MDT result reporter <NUM> in the MN <NUM>. In another embodiment, the MDT result reporter <NUM> may receive the measurement result generated by the MDT measurement executor <NUM> after executing the portion of the MDT measurement, and report the measurement result to the network management, e.g. a first TCE device, of the wireless network. In yet another embodiment, the MDT result reporter <NUM> may transmit, via the transmitter <NUM>, the measurement result generated by the MDT measurement executor <NUM> to the MN <NUM>, which will report the measurement result to a second TCE device, which may be the same as or different from the first TCE device. In still another embodiment, the MDT result reporter <NUM> receives a second measurement result from the MN <NUM> that executes another portion of the MDT measurement to generate the second measurement result. The MDT result reporter <NUM> may report the second measurement result to a third TCE of the wireless network.

In one embodiment, the configuration message analyzer <NUM> may work similarly to the configuration message analyzer <NUM> in the MN <NUM>. In another embodiment, the configuration message analyzer <NUM> may receive, via the receiver <NUM> from the MN <NUM>, configuration information for an MDT measurement to be executed on a terminal in the wireless network. The configuration message analyzer <NUM> may analyze the configuration information to determine that the MDT measurement comprises a first portion to be executed by the MN <NUM>, a second portion to be executed by the SN <NUM>, and a third portion to be executed by the terminal in the wireless network. The configuration message analyzer <NUM> may also analyze the configuration information to determine that the MDT measurement comprises information related to at least one of: measurement objects of the MDT measurement; measured values of the MDT measurement; a location measurement manner; link direction of the MDT measurement; a location measurement provider; trace collection entity device information; operator information; one or more MDT measurement collection locations; one or more network elements that report the MDT measurement result; measurement type of the MDT measurement; base station information that triggers the MDT measurement; and network management information of the base station that triggers the MDT measurement.

In yet another embodiment, the configuration message analyzer <NUM> receives, via the receiver <NUM> from the MN <NUM>, a request for an MDT measurement. The configuration message analyzer <NUM> analyzes the request to determine that the request comprises first configuration information for the MDT measurement. The configuration message analyzer <NUM> may send the first configuration information to the MDT measurement configurator <NUM> for determining whether the SN <NUM> agrees with the first configuration information, i.e. whether there is an MDT conflict between the MN <NUM> and the SN <NUM>.

In one embodiment, the feedback generator <NUM> may work similarly to the feedback generator <NUM> in the MN <NUM>. In another embodiment, the feedback generator <NUM> may generate a feedback in response to the configuration information for the MDT measurement desired by the MN <NUM>, and transmit the feedback via the transmitter <NUM> to the MN <NUM>. In one example, the feedback comprises a confirmation of the configuration information for the MDT measurement to instruct the MN <NUM> to execute the MDT measurement based on the configuration information via a terminal in the wireless network. In another example, the feedback comprises a conflict indication indicating that the SN <NUM> has triggered an existing MDT measurement, which is same as the MDT measurement and to be executed on the same terminal. By transmitting this feedback, the SN <NUM> instructs the MN <NUM> to stop executing or not to execute the MDT measurement via the terminal in the wireless network.

It can be understood by one skilled in the art that the roles of the MN <NUM> and the SN <NUM> may be exchanged in accordance with various embodiments of the present teaching. The various modules discussed above are coupled together by a bus system <NUM>. The bus system <NUM> can include a data bus and, for example, a power bus, a control signal bus, and/or a status signal bus in addition to the data bus. It is understood that the modules of the SN <NUM> can be operatively coupled to one another using any suitable techniques and mediums.

Although a number of separate modules or components are illustrated in <FIG>, persons of ordinary skill in the art will understand that one or more of the modules can be combined or commonly implemented. For example, the processor <NUM> can implement not only the functionality described above with respect to the processor <NUM>, but also implement the functionality described above with respect to the configuration message analyzer <NUM>. Conversely, each of the modules illustrated in <FIG> can be implemented using a plurality of separate components or elements.

<FIG> illustrates a flow chart for a method <NUM> performed by an SN, e.g. the SN <NUM> in <FIG>, for configuring MDT under a multi-connectivity architecture, in accordance with some embodiments of the present disclosure. At operation <NUM>, the SN receives a request for an MDT measurement from an MN in a same wireless network under a multi-connectivity architecture. The SN analyzes at operation <NUM> the request to determine whether there is an MDT conflict between the MN and the SN. The SN transmits at operation <NUM> a configuration message for the MDT measurement to the MN. At operation <NUM>, the SN receives a feedback in response to the configuration message from the MN. The SN executes at operation <NUM> at least a portion of the MDT measurement.

According to various embodiments of the present disclosure, a method is provided for configuring MDT under a multi-connectivity architecture. Each network element (NE) participating in the MDT can independently determine how to trigger the measurement. In addition to configuring the measurement configuration of the NE, each NE can also allocate part of the measurement to other NE configurations. For example, when an MN network element configures an M6 measurement (Packet Delay measurement) for a certain terminal, the MN may give the base station side measurement configuration of M6 to the MN base station to implement, and give the terminal side measurement of M6 to the terminal through the control plane of the SN, and give the positioning measurement configuration to the SN base station. After the measurement is completed, the SN collects the measurement results of the terminal and the SN base station and reports the measurement results to the MN according to the configuration information, or collects the measurement results of the terminal and the SN base station according to the configuration and reports the measurement results to the TCE device. Therefore, the method provides that the network element that triggers the MDT transmits the MDT configuration information to the base station that executes the MDT through the inter-base station interface, and the base station that needs to execute the MDT performs the measurement.

<FIG> illustrates an exemplary method for configuring MDT under a multi-connectivity architecture, in accordance with a first embodiment of the present disclosure. As shown in <FIG>, the MN <NUM> transmits the MDT configuration to the SN <NUM> and the SN <NUM> performs the MDT according to the configuration. After the measurement is completed, the SN <NUM> transmits the measurement report directly to TCE. In an alternative embodiment, the SN receives a signaling sent from the core network, where the signaling includes a configuration message for the MDT. Then the SN transmits the configuration to the MN. After the measurement at the MN, the MN transmits the report directly to TCE. The triggered measurement may be a signaling-based MDT measurement or a management-based MDT measurement.

In the first embodiment as shown in <FIG>, The MN <NUM> transmits at Step <NUM> the MDT measurement configuration information, e.g. configuration parameters, to the SN <NUM>. The MN <NUM> triggers the MDT measurement. The trigger may be due to signaling-based MDT measurement and/or management-based MDT measurement. In this example, the MN <NUM> determines to have the MDT measurement. The MN <NUM> determined that the SN <NUM> undertakes the measuring task. The MN <NUM> transmits a message to the SN <NUM> through inter-base station interface messages, such as an XN interface, an X2 interface, etc. The message can be a modification based on an existing message, or it can be a new message.

The MDT measurement configuration parameters may include one or a combination of the following parameters: measured values (including M1, M2, M3, M4, M5, M6, M7); measurement objects (including the MCG bearer, the SCG bearer, the SCG RLC bearer of split bearer, the MCG RLC bearer of split bearer, the QCI, all the bearers of the UE, flow ID, slice information (e.g., S-NSSAI, etc.)); location measurement manner (E-CID, GPS, Bluetooth, Wi-Fi); link direction of the MDT measurement (uplink measurement, downlink measurement); location measurement provider (terminal or base station); TCE device information (TCE identifier, TCE address); operator Information (PLMN ID); measurement collection location (designated MN network element, designated SN network element, separate collection); NEs to which the measurement result is reported to or NEs that report the MDT measurement result (designated MN NEs, designated SN NEs, separate report); measurement type (management-based MDT measurement, signaling-based MDT measurement); base station information (e.g., gNB ID) that triggers the measurement; and network management information (such as DNS information or address information of the network management) of the base station that triggers the measurement. The parameters may be configured in a combined form to an SN network element. For example, to enable the SN network element to directly report the measurement result to the correct TCE device, when configuring the parameters, the MN may transmit the TCE device information (such as address information and TCE device number) to the SN network element. Based on this information, the SN can transmit the report to the correct TCE device. For example, to enable the TCE network element to correctly identify which network element triggered the measurement result, the MN network element may transmit its own device information (for example, the base station number, e.g., the DNS information of the base station network management system) to the SN. When the SN transmits the report to the TCE, the report includes the MN network element equipment information as well, so that the TCE equipment can statistically determine that the received measurement report is due to an MDT measurement triggered by which network element.

The SN <NUM> at Step <NUM> transmits a feedback message for performing the MDT measurement desired by the MN <NUM>. At Step <NUM>, the SN <NUM> and/or the terminal perform the MDT measurement, and the SN <NUM> is responsible for collecting the MDT measurement results. At Step <NUM>, after the SN <NUM> finishes the measurement, the SN <NUM> reports the measurement result to the TCE device according to the configuration.

<FIG> illustrates another exemplary method for configuring MDT under a multi-connectivity architecture, in accordance with a second embodiment of the present disclosure. In the second embodiment, the PDCP layer of the split bearer is on the SN network element. The MN decomposes the measurement into three parts (the measurement part performed by MN, the measurement part performed by the terminal, and the measurement part performed by SN). The MN transmits the MDT measurement configuration to the terminal for performing the measurement. The MN itself performs the measurement, and at the same time the MN transmits the MDT configuration to the SN, which performs the measurement as well. After the measurement is completed, the MN side is responsible for collecting the measurement result at the MN side and reporting it to a first TCE. The SN is responsible for collecting the measurement result at the SN side and reporting it to a second TCE, which may be the same as or different from the first TCE. Each MDT measurement has a trace ID, e.g. in terms of a UE ID, time etc., that identifies the MDT measurement. Each report of the measurement result carries a trace ID of the MDT measurement and identifies the MDT measurement was performed by which UE, at which time, at which location, with what measurement parameters, etc..

As shown in <FIG>, at Step <NUM>, the MN <NUM> transmits the MDT measurement configuration to the SN <NUM>. The MN <NUM> triggers MDT measurement. The difference from the first embodiment is that the MN <NUM> can decompose the MDT measurement into three parts, which include the MN network element measurement part, the SN network element measurement part, and the terminal measurement part. The MN <NUM> measures the primary node RLC bearers under the branch bearers. The SN <NUM> measures the secondary node RLC bearers under the branch bearers, and the terminal measures the location information. The difference from the Step <NUM> of the first embodiment is that the MN <NUM> transmits the MDT measurement configuration parameters of the SN network element measurement part to the SN network element. The MDT measurement configuration parameters include the various parameters described above. The parameters may be configured in a combined form to the SN network element. The terminal measurement part may also be configured by the SN <NUM> to the terminal.

At Step <NUM>, the SN <NUM> transmits a feedback message regarding performing MDT measurement to the MN base station. The SN performs MDT measurement configured by the MN and transmits a feedback message to the MN base station. At Step <NUM>, the MN <NUM> and the SN <NUM> and the terminal respectively perform measurements. The MN <NUM> is responsible for the MN network element measurement part, and the MN <NUM> is responsible for collecting the measurement results of the MN network element measurement part and/or the terminal measurement part. The SN <NUM> is responsible for SN network element measurement part, and the SN <NUM> is responsible for collecting the measurement results of the SN network element measurement part and/or the terminal measurement part. At Step <NUM>, after the measurement is completed, the MN <NUM> and the SN <NUM> respectively report the measurement results to the TCE device. In order for a TCE device to recognize whether measurement reports from different devices belong to the same MDT measurement, the MN and the SN may carry some auxiliary information when reporting the result. The TCE can associate the measurement results respectively reported by the MN and the SN according to the auxiliary information. Such auxiliary information includes: the information of the terminal, the time of measurement, the number of the measurement, etc..

In a third embodiment, after the measurement is completed, the SN reports the measurement results to the MN, and the MN reports the measurement results together or as an aggregation to the TCE device. The measurement results may use standardized inter-base-station interfaces, such as Xn, X2 interfaces, or inter-base station IP connections.

There may be an MDT conflict under a multi-connectivity architecture, e.g. when multiple network elements respectively perform a same type of measurement at a same UE. For example, the MN network element triggers a signaling-based MDT measurement for a certain terminal, while at the same time the network management of the SN base station triggers a management-based MDT measurement for the same terminal. As such, the MN and the SN select the same measurement of the same terminal. This can be solved through negotiation between the base stations. For example, when a certain service of a terminal is being measured by the MN, the SN also chooses to measure the same service of the terminal. At this time, the MN is responsible for resolving the conflict. The SN transmits the measurement configuration (including TCE, PLMN, measurement object, etc.) established at the SN side to the MN before performing the measurement. If the MN does not find any conflict, the SN will start measurement after a confirmation feedback is returned. If the MN finds a conflict, a measurement conflict indication may be carried in the feedback message. After receiving the measurement conflict indication, the SN will not continue the measurement.

The MDT triggered by the MN or the SN may be signaling-based MDT measurement and management-based MDT measurement. This may be similar to the two measurement trigger modes referred in 3GPP TS <NUM> protocol. The signaling-based MDT measurement means that the MN base station receives the measurement configuration message sent by the network management of the core network. The measurement configuration message explicitly indicates MDT measurement for a specific terminal, and the measurement parameters may be configured by the core network. The base station performs MDT according to configuration of the core network. The management-based MDT measurement means that the network management of the MN network element or the SN network element requests the access network element to select a suitable terminal for MDT measurement. The MN or SN will select one or more terminals, and perform the MDT measurement according to the requirements of the network management.

The message via which the MN and the SN transmit the MDT measurement configuration information may use an inter-base station control plane interface such as an XN or an X2 interface, with reference to the 3GPP TS <NUM> protocol or the TS <NUM> protocol. The message may reuse existing inter-base station interface messages or use new inter-base station interface messages. Reusing interface messages can be SGNB ADDITION REQUEST, SGNB MODIFICATION REQUIRED and other messages. Reusing methods include adding new fields. The measurement report sent by the MN and the SN may use an inter-base station control plane interface such as Xn or X2 or use a data plane interface. For example, the measurement report may be transmitted through an IP data link.

<FIG> illustrates an exemplary method for configuring MDT under a multi-connectivity architecture to avoid a conflict between the MN and the SN, in accordance with a fourth claimed embodiment of the present disclosure. The MN and the SN trigger measurements simultaneously, which causes measurement conflicts. The MN and the SN network elements make their own decisions independently, and the same measurement objects of the same terminal are selected. Before implementing the measurement, the SN transmits the MDT configuration to the MN network element. At this time, the MN starts to measure the same measurement object of the same terminal. The MN network element indicates a conflict in the feedback message, and the SN stops performing the measurement.

As shown in <FIG>, at Step <NUM>, the MN <NUM> has triggered a first MDT measurement on a terminal. Also at Step <NUM>, the SN <NUM> wants to trigger a second MDT measurement on the terminal as well. At Step <NUM>, the SN <NUM> transmits the MDT configuration of the second MDT to the MN <NUM>. In this embodiment, the SN network element determines the MDT measurement for a certain terminal. But the MDT measurement has been performed at the MN network element. Before triggering the MDT measurement, the SN transmits the MDT configuration to the MN network element to confirm that there is no conflict. At Step <NUM>, the MN <NUM> transmits a feedback message to the SN <NUM>. The feedback message carries a measurement conflict indication. At Step <NUM>, the SN <NUM> stops the second MDT measurement after receiving the conflict indication.

In a fifth claimed embodiment, the MN and the SN trigger MDT measurements simultaneously, which causes measurement conflicts. The MN and the SN network elements make their own decisions independently, and the same measurement objects of the same terminal are selected. Before performing the measurement, the MN transmits the MDT configuration to the SN network element. The SN network element now has started to measure the same measurement objects of the same terminal. The SN network element indicates a conflict in the feedback message, and the MN network element stops performing the measurement. Unlike the fourth embodiment, the MN stops the MDT measurement in this embodiment.

<FIG> illustrates another exemplary method for configuring MDT under a multi-connectivity architecture to avoid a conflict between the MN and the SN, in accordance with a sixth embodiment of the present disclosure. The MN and the SN trigger measurements simultaneously, which causes measurement conflicts. The MN and the SN network elements make their own decisions independently, and the same measurement objects of the same terminal are selected. Eventually the MDT measurement triggered by the MN is performed. Before performing measurement, the MN transmits the MDT configuration to the SN network element. Before receiving the feedback message, the MN receives from the SN a measurement request for the same measurement objects of the same terminal. The MN returns a conflict indication and continues to perform the measurement. The SN terminates the measurement.

As shown in <FIG>, at Step <NUM>, before performing a first MDT measurement on a terminal, the MN <NUM> transmits the MDT measurement configuration of the first MDT to the SN <NUM>. At Step <NUM>, the SN <NUM> wants to trigger a second MDT on the same terminal. As such, within Step <NUM>, the MN <NUM> receives the MDT measurement configuration message of the second MDT sent by the SN <NUM> before receiving the feedback message. It can be understood that the orders of the Step <NUM> and the Step <NUM> can be exchanged or the Step <NUM> and the Step <NUM> may happen at the same time.

Through the configuration message from the SN <NUM>, the MN <NUM> can learn that the MDT measurement that the SN <NUM> wishes to measure has been performed on the MN <NUM>. At Step <NUM>, the MN <NUM> transmits a feedback message to the SN <NUM>. The feedback message carries a measurement conflict indication. After receiving the feedback message, the SN <NUM> learns that its desired second MDT measurement is also going to be performed on the MN <NUM>. Therefore, the SN <NUM> terminates at Step <NUM> the desired second MDT measurement. Also at Step <NUM>, the MN <NUM> receives a feedback message returned by the SN <NUM>. The MN <NUM> performs at Step <NUM> the first MDT measurement. In an alternative embodiment, after transmitting the configuration message in Step <NUM>, the MN <NUM> can also start the first MDT measurement directly. In another embodiment, the MDT measurement triggered by the SN is performed eventually when there is an MDT conflict between the MN and the SN.

<FIG> illustrates yet another exemplary method for configuring MDT under a multi-connectivity architecture to avoid a conflict between the MN and the SN, in accordance with a seventh claimed embodiment of the present disclosure. The MN and the SN trigger measurements simultaneously, which causes measurement conflicts. The MN and the SN network elements make their own decisions independently, and the same measurement objects of the same terminal are selected. Eventually the MDT measurement triggered by the MN is performed. The SN transmits the MDT configuration to the MN before the measurement is performed. Before receiving the feedback message, the SN receives from the MN a measurement request for the same measurement objects of the same terminal. The SN returns a conflict indication and terminates the measurement.

As shown in <FIG>, at Step <NUM>, the SN <NUM> transmits an MDT measurement configuration regarding a first MDT to the MN <NUM> before performing the first MDT measurement on a terminal. At Step <NUM>, the SN <NUM> receives an MDT measurement configuration message regarding a second MDT on the terminal sent by the MN <NUM> before receiving the feedback message. It can be understood that the orders of the Step <NUM> and the Step <NUM> can be exchanged or the Step <NUM> and the Step <NUM> may happen at the same time.

Based on the feedback message, the SN <NUM> can learn that there is a conflict between the MDT measurement that the SN <NUM> desires to measure and the MDT measurement that the MN <NUM> desires to measure. The SN <NUM> terminates its desired MDT measurement at Step <NUM>. Also at Step <NUM>, the SN <NUM> transmits a feedback message to the MN <NUM>. The feedback message may or may not carry a measurement conflict indication. This is because after receiving the feedback message, the SN <NUM> learns that its desired MDT measurement is also going to be performed on the MN <NUM>. Therefore, the SN <NUM> terminates its desired MDT measurement. But this may not be necessary for the MN <NUM> to know. At Step <NUM>, the MN <NUM> transmits to the SN <NUM> a feedback message regarding the configuration message sent by the SN <NUM> in Step <NUM>. The MN <NUM> performs at Step <NUM> the second MDT measurement. In another embodiment, the MDT measurement triggered by the SN is performed eventually when there is an MDT conflict between the MN and the SN.

Claim 1:
A method performed by a first wireless communication node, the method comprising:
transmitting, to a second wireless communication node, configuration information for a minimization of drive test, MDT, measurement, wherein the first wireless communication node and the second wireless communication node are both nodes in a wireless network, and wherein the MDT measurement is to be executed by a wireless communication device in the wireless network; and
receiving, from the second wireless communication node, a feedback in response to the configuration information for the MDT measurement, the feedback comprising a conflict indication indicating that the second wireless communication node has triggered an existing MDT measurement, which is same as the MDT measurement, on the wireless communication device; and
stopping the MDT measurement at the first wireless communication node in response to the feedback.