Target cells and handover time predictions to limit unnecessary handovers

Abstract

A method, computer program, and apparatus are provided for causing a user device to receive from a network an indication for a first time period and an indication of at least one metric predicted within the first time period for at least a serving cell and a plurality of target cells of the network; further, receive from the network an indication of a method for identifying a potential handover opportunity between a serving cell and at least one of the plurality of target cells within the first time period using at least one metric; identify a first set of potential handover opportunities between a serving cell and at least one of the plurality of target cells within the first time period using at least one metric; and signal to the network an indication of at least one of the first set of potential handover opportunities.

Description

Technical Field

[0001] The examples described in this specification generally relate to apparatuses, methods, and computer programs, and more particularly (but not limited thereto) to apparatuses, methods, and computer programs for an apparatus.

Background Art

[0002] A communication system can be considered as a facility that enables a communication session between two or more entities such as communication devices, base stations, and / or other nodes by providing a carrier between various entities involved in a communication path.

[0003] The communication system may be a wireless communication system. Examples of wireless systems include public land mobile networks (PLMNs) operating based on wireless standards such as those provided by 3GPP, satellite-based communication systems, and various wireless local networks such as wireless local area networks (WLAN). A wireless system can usually be divided into cells and is thus often called a cellular system.

[0004] Communication systems and related devices typically operate according to a given standard or specification that defines what is permitted to various entities associated with the system and how it should be achieved. The communication protocols and / or parameters used for connections are also generally defined. An example of a standard is the so-called 5G standard.

Summary of the Invention

[0005] According to a first aspect, a method is provided for user equipment, the method comprising: receiving from a network an indication of a first time period and an indication of at least one metric expected within the first time period for at least a serving cell and a plurality of target cells of the network; receiving from the network an indication of a method for identifying potential handover opportunities between a serving cell and at least one of the plurality of target cells within the first time period using at least one metric, wherein the potential handover opportunity comprises, respectively, a combination of the identity of a target cell and a time instance for performing the handover; identifying a first set of potential handover opportunities between a serving cell and at least one of the plurality of target cells within the first time period using at least one metric, and signaling to the network an indication of at least one of the first set of potential handover opportunities.

[0006] The step of signaling an indication of at least one of the first set of potential handover opportunities to the network may include the steps of signaling an indication of the first set of multiple potential handover opportunities to a serving cell, receiving an indication of a single potential handover opportunity from the first set of multiple potential handover opportunities from the serving cell, and performing a handover to a target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity.

[0007] The identification step may include, for each target cell identified by the plurality of handover opportunities, predicting the value of at least one metric in different time instances within the first time period in order to form the respective predicted metric.

[0008] The indications for the first set of multiple potential handover opportunities signaled to a serving cell may include, for each target cell identified by the first set of multiple potential handover opportunities, at least one of the following: an indication of a time instance in the window when the predicted metric of that target cell is greater than a threshold; an indication of a time instance in the window when the predicted metric of that target cell is less than a threshold; an indication of a time instance in the window when the predicted metric of that target cell is greater by an offset than the same metric predicted for another target cell; an indication of a time instance in the window when the predicted metric of that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of a time instance in the window when the predicted metric of that target cell is less by an offset than the same metric predicted for another target cell; or an indication of a time instance in the window when the predicted metric of that target cell is less by an offset than the same metric predicted for a serving cell.

[0009] The step of signaling an indication of at least one of the first set of potential handover opportunities to the network may comprise the steps of signaling an indication of a single potential handover opportunity to a serving cell, and performing a handover to a target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity.

[0010] The identification step may comprise the steps of predicting the value of at least one metric in different time instances within the first time period to form a predicted metric for each target cell identified by a first set of potential handover opportunities, and selecting a single potential handover opportunity by selecting a single potential handover opportunity using the predicted metric.

[0011] At least one of the predicted values ​​for a target cell may include at least one of the following: an indication of the time instance within the window when the predicted metric for that target cell is greater than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is less than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for another target cell; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for another target cell; or an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for a serving cell.

[0012] The method may also include the steps of: abstaining from performing a handover in one of the first handover opportunities in a first set; and performing a handover to a selected target cell in one of the second handover opportunities, wherein the second handover opportunity occurs later than the first handover opportunity.

[0013] The method may comprise the steps of: identifying a second set of potential handover opportunities between a serving cell and at least one of a plurality of target cells within a first time period, using at least one metric, wherein the second time is later than the first time; and signaling the serving cell to at least one indication of the second set of potential handover opportunities.

[0014] At least one metric may include reference signal received power and / or reference signal received quality.

[0015] According to a second aspect, a method is provided for a serving access node to provide a serving cell to a user device, the method comprising: signaling the user device with an indication of a first time period and an indication of at least one metric expected within the first time period for at least a serving cell and a plurality of target cells; signaling the user device with an indication of a method for identifying a potential handover opportunity between the serving cell and at least one of the plurality of target cells within the first time period using at least one metric, wherein the potential handover opportunity comprises a combination of the identity of the target cell and a time instance for performing the handover; and receiving from the user device an indication of at least one of a first set of potential handover opportunities for handing over the user device from the serving cell to at least one of the plurality of serving cells within the first time period using at least one metric.

[0016] The step of receiving an indication of at least one of the first set of potential handover opportunities may include the steps of receiving an indication of a single potential handover opportunity and causing a handover to the target cell identified by the single potential handover opportunity to be performed in the time instance indicated by the single potential handover opportunity.

[0017] The step of receiving an indication of at least one of the first set of potential handover opportunities may include receiving indications of the first set of multiple potential handover opportunities from the user device; selecting a single potential handover opportunity from the potential handover opportunities by determining that a target cell identified by a single potential handover opportunity can also provide coverage to the user device during a time instance associated with another of the first set of potential handover opportunities; and signaling the user device an indication of a single potential handover opportunity from the first set of multiple potential handover opportunities.

[0018] The step of receiving an indication of at least one of a first set of potential handover opportunities may include receiving values ​​of at least one metric at different time instances within the first time period to form a predicted metric for each target cell identified by the first set of potential handover opportunities, and the step of selecting a single potential handover opportunity may include selecting a single potential handover opportunity using the predicted metric.

[0019] At least one of the predicted values ​​for a target cell may include at least one of the following: an indication of the time instance within the window when the predicted metric for that target cell is greater than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is less than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for another target cell; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for another target cell; or an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for a serving cell.

[0020] The method may include the step of handing over a user device to a target cell identified by a single potential handover opportunity in a time instance indicated by a single potential handover opportunity.

[0021] This method may include the step of having the user device perform a handover by refraining from performing a handover in one of the first handover opportunities of a first set, and performing a handover to one of a selected target cell in one of the second handover opportunities, wherein the second handover opportunity occurs after the first handover opportunity.

[0022] The method may include the steps of: receiving an indication from a user device of a second set of potential handover opportunities between a serving cell and at least one of a plurality of target cells within a first time period, wherein the second set of potential handover opportunities relates to a set of predictions made using metrics for a first time period beginning at a second time, and the second time being later than the first time; and in a time instance indicated by one of the second set of potential handover opportunities, handing over the user device to a target cell identified by at least one of the second set of potential handover opportunities.

[0023] At least one metric may include reference signal received power and / or reference signal received quality.

[0024] According to a third aspect, a device for user equipment is provided, the device includes means for receiving from a network an indication of a first time period and an indication of at least one metric expected within the first time period for at least a serving cell and a plurality of target cells of the network; receiving from the network an indication of a method for identifying a potential handover opportunity between a serving cell and at least one of the plurality of target cells within the first time period using at least one metric, wherein the potential handover opportunity comprises, respectively, a combination of the identity of the target cell and a time instance for performing the handover; identifying a first set of potential handover opportunities between a serving cell and at least one of the plurality of target cells within the first time period using at least one metric, and signaling to the network an indication of at least one of the first set of potential handover opportunities.

[0025] Means for signaling an indication of at least one of the first set of potential handover opportunities to the network may include means for signaling an indication of the first set of multiple potential handover opportunities to a serving cell, means for receiving an indication of a single potential handover opportunity from the first set of multiple potential handover opportunities from the serving cell, and means for performing a handover to a target cell identified by the single potential handover opportunity in a time instance indicated by the single potential handover opportunity.

[0026] The identification means may include means for predicting the value of at least one metric in different time instances within the first time period in order to form a predicted metric for each target cell identified by the plurality of handover opportunities.

[0027] The indication of the first set of the plurality of potential handover opportunities signaled to the serving cell is, for each target cell identified by the first set of the plurality of potential handover opportunities, an indication of a time instance within the window when the predicted metric of the target cell is greater than a threshold, an indication of a time instance within the window when the predicted metric of the target cell is less than the threshold, an indication of a time instance within the window when the predicted metric of the target cell is greater by an offset amount than the same metric predicted for another target cell, an indication of a time instance within the window when the predicted metric of the target cell is greater by an offset amount than the same metric predicted for the serving cell, an indication of a time instance within the window when the predicted metric of the target cell is less by an offset amount than the same metric predicted for another target cell, or an indication of a time instance within the window when the predicted metric of the target cell is less by an offset amount than the same metric predicted for the serving cell, and may comprise at least one of them.

[0028] Means for signaling to the network at least one indication of the first set of potential handover opportunities may comprise means for signaling to the serving cell an indication of a single potential handover opportunity, and means for performing a handover to a target cell identified by a single potential handover opportunity at the time instance indicated by the single potential handover opportunity.

[0029] For each target cell identified by a first set of potential handover opportunities, the means for identification may comprise means for predicting the value of at least one metric at different time instances within the first time period to form a respective predicted metric, and means for selecting a single potential handover opportunity by using the predicted metrics to select a single potential handover opportunity.

[0030] At least one of the predicted values of the target cell comprises at least one of an indication of a time instance within the window when the predicted metric of the target cell is greater than a threshold, an indication of a time instance within the window when the predicted metric of the target cell is less than a threshold, an indication of a time instance within the window when the predicted metric of the target cell is greater by an offset amount than the same metric predicted for another target cell; an indication of a time instance within the window when the predicted metric of the target cell is greater by an offset amount than the same metric predicted for the serving cell; an indication of a time instance within the window when the predicted metric of the target cell is less by an offset amount than the same metric predicted for another target cell; or an indication of a time instance within the window when the predicted metric of the target cell is less by an offset amount than the same metric predicted for the serving cell.

[0031] The device may include means for refraining from performing a handover in one of the first handover opportunities in a first set, and performing a handover to a selected target cell in one of a plurality of target cells in one of the second handover opportunities, wherein the second handover opportunity occurs after the first handover opportunity.

[0032] The device may include means for identifying a second set of potential handover opportunities between a serving cell and at least one of a plurality of target cells within a first time period, which begins at a second time, using at least one metric, wherein the second time is later than the first time, and for signaling the serving cell to at least one indication of the second set of potential handover opportunities.

[0033] At least one metric may include reference signal received power and / or reference signal received quality.

[0034] According to a fourth aspect, a device for a serving access node that provides a serving cell to a user device is provided, the device includes means for signaling to the user device an indication of a first time period and an indication of at least one metric expected within the first time period for at least a serving cell and a plurality of target cells; signaling to the user device an indication of a method for identifying a potential handover opportunity between the serving cell and at least one of the plurality of target cells within the first time period using at least one metric, wherein the potential handover opportunity comprises a combination of the identity of the target cell and a time instance for performing the handover; and receiving from the user device an indication of at least one of a first set of potential handover opportunities for handing over the user device from the serving cell to at least one of the plurality of serving cells within the first time period using at least one metric.

[0035] Means for receiving an indication of at least one of the first set of potential handover opportunities may include means for receiving an indication of a single potential handover opportunity, and means for causing a handover to a target cell identified by the single potential handover opportunity to be performed in the time instance indicated by the single potential handover opportunity.

[0036] Means for receiving an indication of at least one of the first set of potential handover opportunities may include, from a user device, means for receiving indications of the first set of multiple potential handover opportunities; means for selecting a single potential handover opportunity from the potential handover opportunities by determining that a target cell identified by a single potential handover opportunity can also provide coverage to the user device during a time instance associated with another of the first set of potential handover opportunities; and means for signaling the user device an indication of a single potential handover opportunity from the first set of multiple potential handover opportunities.

[0037] The means for receiving an indication of at least one of a first set of potential handover opportunities may include means for receiving values ​​of at least one metric in different time instances within the first time period to form a predicted metric for each target cell identified by the first set of potential handover opportunities, and the means for selecting a single potential handover opportunity may include means for selecting a single potential handover opportunity using the predicted metric.

[0038] At least one of the predicted values ​​for a target cell may include at least one of the following: an indication of the time instance within the window when the predicted metric for that target cell is greater than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is less than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for another target cell; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for another target cell; or an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for a serving cell.

[0039] The device may include means for performing a handover of a user device to a target cell identified by a single potential handover opportunity in a time instance indicated by a single potential handover opportunity.

[0040] The device may include means for causing a user device to perform a handover by refraining from performing a handover in one of the first handover opportunities of a first set, and performing a handover to one of a selected target cell in one of the second handover opportunities, wherein the second handover opportunity occurs after the first handover opportunity.

[0041] The device may include means for receiving an indication from a user device of a second set of potential handover opportunities between a serving cell and at least one of a plurality of target cells within a first time period, wherein the second set of potential handover opportunities relates to a set of predictions made using metrics for a first time period starting from a second time, and the second time is later than the first time, and for handing over the user device to a target cell identified by at least one of the second set of potential handover opportunities in a time instance indicated by one of the second set of potential handover opportunities.

[0042] At least one metric may include reference signal received power and / or reference signal received quality.

[0043] According to a fifth aspect, a device for user equipment is provided, the device comprising at least one processor and at least one memory comprising software code that, when executed by the at least one processor, causes the device to receive from a network an indication of a first time period and an indication of at least one metric expected within the first time period for at least a serving cell and a plurality of target cells of the network; receive from the network an indication of a method for identifying a potential handover opportunity between a serving cell and at least one of the plurality of target cells within the first time period using at least one metric, wherein the potential handover opportunity comprises, respectively, a combination of the identity of the target cell and a time instance for performing the handover; identify a first set of potential handover opportunities between a serving cell and at least one of the plurality of target cells within the first time period using at least one metric, and signal to the network an indication of at least one of the first set of potential handover opportunities.

[0044] The step of signaling an indication of at least one of the first set of potential handover opportunities to the network may include the steps of signaling an indication of the first set of multiple potential handover opportunities to a serving cell, receiving an indication of a single potential handover opportunity from the first set of multiple potential handover opportunities from the serving cell, and performing a handover to a target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity.

[0045] The identification step may include, for each target cell identified by the plurality of handover opportunities, predicting the value of at least one metric in different time instances within the first time period in order to form the respective predicted metric.

[0046] The indications for the first set of multiple potential handover opportunities signaled to a serving cell may include, for each target cell identified by the first set of multiple potential handover opportunities, at least one of the following: an indication of a time instance in the window when the predicted metric of that target cell is greater than a threshold; an indication of a time instance in the window when the predicted metric of that target cell is less than a threshold; an indication of a time instance in the window when the predicted metric of that target cell is greater by an offset than the same metric predicted for another target cell; an indication of a time instance in the window when the predicted metric of that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of a time instance in the window when the predicted metric of that target cell is less by an offset than the same metric predicted for another target cell; or an indication of a time instance in the window when the predicted metric of that target cell is less by an offset than the same metric predicted for a serving cell.

[0047] The step of signaling an indication of at least one of the first set of potential handover opportunities to the network may comprise the steps of signaling an indication of a single potential handover opportunity to a serving cell, and performing a handover to a target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity.

[0048] The identification step may comprise the steps of predicting the value of at least one metric in different time instances within the first time period to form a predicted metric for each target cell identified by a first set of potential handover opportunities, and selecting a single potential handover opportunity by selecting a single potential handover opportunity using the predicted metric.

[0049] At least one of the predicted values ​​for a target cell may include at least one of the following: an indication of the time instance within the window when the predicted metric for that target cell is greater than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is less than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for another target cell; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for another target cell; or an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for a serving cell.

[0050] The device may perform the following actions: refrain from performing a handover in one of the first handover opportunities in a first set; and perform a handover to a selected target cell in one of the second handover opportunities, wherein the second handover opportunity occurs later than the first handover opportunity.

[0051] The device may be configured to identify a second set of potential handover opportunities between a serving cell and at least one of a plurality of target cells within a first time period, using at least one metric, wherein the second time is later than the first time, and to signal at least one indication of the second set of potential handover opportunities to the serving cell.

[0052] At least one metric may include reference signal received power and / or reference signal received quality.

[0053] According to a sixth aspect, a device for a serving access node that provides a serving cell to a user device is provided, the device comprising at least one processor and at least one memory comprising software code that, when executed by at least one processor, causes the device to signal to the user device an indication of a first time period and an indication of at least one metric expected within the first time period for at least a serving cell and a plurality of target cells; to signal to the user device an indication of a method for identifying a potential handover opportunity between the serving cell and at least one of the plurality of target cells within the first time period using at least one metric, wherein the potential handover opportunity comprises a combination of the identity of the target cell and a time instance for performing the handover; and to receive from the user device an indication of at least one of a first set of potential handover opportunities for handing over the user device from the serving cell to at least one of the plurality of serving cells within the first time period using at least one metric.

[0054] The step of receiving an indication of at least one of the first set of potential handover opportunities may include the steps of receiving an indication of a single potential handover opportunity and causing a handover to the target cell identified by the single potential handover opportunity to be performed in the time instance indicated by the single potential handover opportunity.

[0055] The step of receiving an indication of at least one of the first set of potential handover opportunities may include receiving indications of the first set of multiple potential handover opportunities from the user device; selecting a single potential handover opportunity from the potential handover opportunities by determining that a target cell identified by a single potential handover opportunity can also provide coverage to the user device during a time instance associated with another of the first set of potential handover opportunities; and signaling the user device an indication of a single potential handover opportunity from the first set of multiple potential handover opportunities.

[0056] The step of receiving an indication of at least one of a first set of potential handover opportunities may include receiving values ​​of at least one metric at different time instances within the first time period to form a predicted metric for each target cell identified by the first set of potential handover opportunities, and the step of selecting a single potential handover opportunity may include selecting a single potential handover opportunity using the predicted metric.

[0057] At least one of the predicted values ​​for a target cell may include at least one of the following: an indication of the time instance within the window when the predicted metric for that target cell is greater than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is less than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for another target cell; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for another target cell; or an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for a serving cell.

[0058] The device may be configured to perform the handover of a user device to a target cell identified by a single potential handover opportunity in a time instance indicated by a single potential handover opportunity.

[0059] The device may be configured to allow user equipment to perform a handover by refraining from performing a handover in one of the first handover opportunities in a first set, and by performing a handover to one of a selected target cell in one of the second handover opportunities, wherein the second handover opportunity occurs after the first handover opportunity.

[0060] The device may be configured to receive an indication from a user device of a second set of potential handover opportunities between a serving cell and at least one of a plurality of target cells within a first time period, wherein the second set of potential handover opportunities relates to a set of predictions made using metrics for a first time period starting from a second time, and the second time is later than the first time, and to hand over the user device to the target cell identified by at least one of the second set of potential handover opportunities in a time instance indicated by one of the second set of potential handover opportunities.

[0061] At least one metric may include reference signal received power and / or reference signal received quality.

[0062] According to a seventh aspect, a device for user equipment is provided, comprising: a receiving circuit for receiving from a network an indication of a first time period and an indication of at least one metric predicted within the first time period for at least a serving cell and a plurality of target cells of the network; a receiving circuit for receiving from the network an indication of a method for identifying a potential handover opportunity between a serving cell and at least one of the plurality of target cells within the first time period using at least one metric, wherein the potential handover opportunity comprises a combination of the identity of a target cell and a time instance for performing a handover; an identification circuit for identifying a first set of potential handover opportunities between a serving cell and at least one of the plurality of target cells within the first time period using at least one metric, in a first time period beginning from a first time; and a signaling circuit for signaling to the network an indication of at least one of the first set of potential handover opportunities.

[0063] A signaling circuit for signaling to a network an indication of at least one of the first set of potential handover opportunities may include a signaling circuit for signaling to a serving cell an indication of the first set of multiple potential handover opportunities, a receiving circuit for receiving from the serving cell an indication of a single potential handover opportunity from the first set of multiple potential handover opportunities, and an execution circuit for performing a handover to a target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity.

[0064] The identification circuit for identification may include a prediction circuit for predicting the value of at least one metric in different time instances within the first time period in order to form each of the multiple handover opportunities that identify a target cell.

[0065] The indications for the first set of multiple potential handover opportunities signaled to a serving cell may include, for each target cell identified by the first set of multiple potential handover opportunities, at least one of the following: an indication of a time instance in the window when the predicted metric of that target cell is greater than a threshold; an indication of a time instance in the window when the predicted metric of that target cell is less than a threshold; an indication of a time instance in the window when the predicted metric of that target cell is greater by an offset than the same metric predicted for another target cell; an indication of a time instance in the window when the predicted metric of that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of a time instance in the window when the predicted metric of that target cell is less by an offset than the same metric predicted for another target cell; or an indication of a time instance in the window when the predicted metric of that target cell is less by an offset than the same metric predicted for a serving cell.

[0066] A signaling circuit for signaling to the network an indication of at least one of the first set of potential handover opportunities may comprise a signaling circuit for signaling to a serving cell an indication of a single potential handover opportunity, and an execution circuit for performing a handover to a target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity.

[0067] The identification circuit for identification may include, for each target cell identified by a first set of potential handover opportunities, a prediction circuit for predicting the value of at least one metric in different time instances within the first time period to form a predicted metric for each target cell, and a selection circuit for selecting a single potential handover opportunity by selecting a single potential handover opportunity using the predicted metric.

[0068] At least one of the predicted values ​​for a target cell may include at least one of the following: an indication of the time instance within the window when the predicted metric for that target cell is greater than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is less than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for another target cell; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for another target cell; or an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for a serving cell.

[0069] The device may include a restraint circuit for restraining the execution of a handover in one of the first handover opportunities of a first set, and an execution circuit for performing a handover to one of a selected target cell in one of a plurality of target cells in one of the second handover opportunities, wherein the second handover opportunity occurs after the first handover opportunity.

[0070] The device may include an identification circuit for identifying a second set of potential handover opportunities between a serving cell and at least one of a plurality of target cells within a first time period, using at least one metric, wherein the second time is later than the first time, and a signaling circuit for signaling the serving cell to at least one indication of the second set of potential handover opportunities.

[0071] At least one metric may include reference signal received power and / or reference signal received quality.

[0072] According to the eighth aspect, a device is provided for a serving access node that provides a serving cell to a user device, the device comprising: a signaling circuit for signaling to the user device an indication of a first time period and an indication of at least one metric expected within the first time period for at least a serving cell and a plurality of target cells; a signaling circuit for signaling to the user device an indication of a method for identifying a potential handover opportunity between the serving cell and at least one of the plurality of target cells within the first time period using at least one metric, wherein the potential handover opportunity comprises a combination of the identity of the target cell and a time instance for performing the handover; and a receiving circuit for receiving from the user device an indication of at least one of a first set of potential handover opportunities for handing over the user device from the serving cell to at least one of the plurality of serving cells within the first time period using at least one metric.

[0073] A receiving circuit for receiving an indication of at least one of the first set of potential handover opportunities may comprise a receiving circuit for receiving an indication of a single potential handover opportunity, and a causing circuitry for performing a handover to a target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity.

[0074] A receiving circuit for receiving an indication of at least one of the first set of potential handover opportunities may include: a receiving circuit for receiving indications of the first set of multiple potential handover opportunities from a user device; a selection circuit for selecting a single potential handover opportunity from the potential handover opportunities by determining that a target cell identified by a single potential handover opportunity can also provide coverage to the user device during a time instance in which that target cell is associated with another of the first set of potential handover opportunities; and a signaling circuit for signaling the user device an indication of a single potential handover opportunity from the first set of multiple potential handover opportunities.

[0075] The receiving circuit for receiving an indication of at least one of a first set of potential handover opportunities may include a receiving circuit for receiving values ​​of at least one metric at different time instances within the first time period to form a predicted metric for each target cell identified by the first set of potential handover opportunities, and the selection circuit for selecting a single potential handover opportunity may include a selection circuit for selecting a single potential handover opportunity using the predicted metric.

[0076] At least one of the predicted values ​​for a target cell may include at least one of the following: an indication of the time instance within the window when the predicted metric for that target cell is greater than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is less than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for another target cell; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for another target cell; or an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for a serving cell.

[0077] The device may include a service circuit for handing over user equipment to a target cell identified by a single potential handover opportunity in a time instance indicated by a single potential handover opportunity.

[0078] The device may include a service circuit that causes user equipment to perform a handover by refraining from performing a handover in one of the first handover opportunities of a first set, and performing a handover to one of a selected target cell in one of the second handover opportunities, wherein the second handover opportunity occurs after the first handover opportunity.

[0079] The device comprises a receiving circuit for receiving indications from a user device of a second set of potential handover opportunities between a serving cell and at least one of a plurality of target cells within a first time period, wherein the second set of potential handover opportunities relates to a set of predictions made using a metric for a first time period starting from a second time, and the second time being later than the first time; and a service circuit for causing the user device to hand over to a target cell identified by at least one of the second set of potential handover opportunities in a time instance indicated by one of the second set of potential handover opportunities.

[0080] At least one metric may include reference signal received power and / or reference signal received quality.

[0081] According to the ninth aspect, a non-temporary computer-readable medium is provided for a device for user equipment, comprising program instructions for causing the device to: receive from a network an indication of a first time period and an indication of at least one metric expected within the first time period for at least a serving cell and a plurality of target cells of the network; receive from the network an indication of a method for identifying a potential handover opportunity between a serving cell and at least one of the plurality of target cells within the first time period using at least one metric, wherein the potential handover opportunity comprises a combination of the identity of the target cell and a time instance for performing the handover; identify a first set of potential handover opportunities between a serving cell and at least one of the plurality of target cells within the first time period using at least one metric, and signal an indication of at least one of the first set of potential handover opportunities to the network.

[0082] The step of signaling an indication of at least one of the first set of potential handover opportunities to the network may include the steps of signaling an indication of the first set of multiple potential handover opportunities to a serving cell, receiving an indication of a single potential handover opportunity from the first set of multiple potential handover opportunities from the serving cell, and performing a handover to a target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity.

[0083] The identification step may include, for each target cell identified by the plurality of handover opportunities, predicting the value of at least one metric in different time instances within the first time period in order to form the respective predicted metric.

[0084] The indications for the first set of multiple potential handover opportunities signaled to a serving cell may include, for each target cell identified by the first set of multiple potential handover opportunities, at least one of the following: an indication of a time instance in the window when the predicted metric of that target cell is greater than a threshold; an indication of a time instance in the window when the predicted metric of that target cell is less than a threshold; an indication of a time instance in the window when the predicted metric of that target cell is greater by an offset than the same metric predicted for another target cell; an indication of a time instance in the window when the predicted metric of that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of a time instance in the window when the predicted metric of that target cell is less by an offset than the same metric predicted for another target cell; or an indication of a time instance in the window when the predicted metric of that target cell is less by an offset than the same metric predicted for a serving cell.

[0085] The step of signaling an indication of at least one of the first set of potential handover opportunities to the network may comprise the steps of signaling an indication of a single potential handover opportunity to a serving cell, and performing a handover to a target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity.

[0086] The identification step may comprise the steps of predicting the value of at least one metric in different time instances within the first time period to form a predicted metric for each target cell identified by a first set of potential handover opportunities, and selecting a single potential handover opportunity by selecting a single potential handover opportunity using the predicted metric.

[0087] At least one of the predicted values ​​for a target cell may include at least one of the following: an indication of the time instance within the window when the predicted metric for that target cell is greater than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is less than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for another target cell; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for another target cell; or an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for a serving cell.

[0088] The device may perform the following actions: refrain from performing a handover in one of the first handover opportunities in a first set; and perform a handover to a selected target cell in one of the second handover opportunities, wherein the second handover opportunity occurs later than the first handover opportunity.

[0089] The device may be configured to identify a second set of potential handover opportunities between a serving cell and at least one of a plurality of target cells within a first time period, starting from a second time, using at least one metric, wherein the second time is later than the first time, and to signal at least one indication of the second set of potential handover opportunities to the serving cell.

[0090] At least one metric may include reference signal received power and / or reference signal received quality.

[0091] According to a tenth aspect, a non-temporary computer-readable medium is provided for a device for a serving access node that provides a serving cell to a user device, comprising program instructions for signaling to the user device an indication of a first time period and an indication of at least one metric expected within the first time period for at least a serving cell and a plurality of target cells; signaling to the user device an indication of a method for identifying a potential handover opportunity between the serving cell and at least one of the plurality of target cells within the first time period using at least one metric, wherein the potential handover opportunity comprises a combination of the identity of the target cell and a time instance for performing the handover; and receiving from the user device an indication of at least one of a first set of potential handover opportunities for handing over the user device from the serving cell to at least one of the plurality of serving cells within the first time period using at least one metric.

[0092] The step of receiving an indication of at least one of the first set of potential handover opportunities may include the steps of receiving an indication of a single potential handover opportunity and causing a handover to the target cell identified by the single potential handover opportunity to be performed in the time instance indicated by the single potential handover opportunity.

[0093] The step of receiving an indication of at least one of the first set of potential handover opportunities may include receiving indications of the first set of multiple potential handover opportunities from the user device; selecting a single potential handover opportunity from the potential handover opportunities by determining that a target cell identified by a single potential handover opportunity can also provide coverage to the user device during a time instance associated with another of the first set of potential handover opportunities; and signaling the user device an indication of a single potential handover opportunity from the first set of multiple potential handover opportunities.

[0094] The step of receiving an indication of at least one of a first set of potential handover opportunities may include receiving values ​​of at least one metric at different time instances within the first time period to form a predicted metric for each target cell identified by the first set of potential handover opportunities, and the step of selecting a single potential handover opportunity may include selecting a single potential handover opportunity using the predicted metric.

[0095] At least one of the predicted values ​​for a target cell may include at least one of the following: an indication of the time instance within the window when the predicted metric for that target cell is greater than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is less than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for another target cell; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for another target cell; or an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for a serving cell.

[0096] The device may be configured to perform the handover of a user device to a target cell identified by a single potential handover opportunity in a time instance indicated by a single potential handover opportunity.

[0097] The device may be configured to allow user equipment to perform a handover by refraining from performing a handover in one of the first handover opportunities in a first set, and by performing a handover to one of a selected target cell in one of the second handover opportunities, wherein the second handover opportunity occurs after the first handover opportunity.

[0098] The device may be configured to receive an indication from a user device of a second set of potential handover opportunities between a serving cell and at least one of a plurality of target cells within a first time period, wherein the second set of potential handover opportunities relates to a set of predictions made using metrics for a first time period starting from a second time, and the second time is later than the first time, and to hand over the user device to the target cell identified by at least one of the second set of potential handover opportunities in a time instance indicated by one of the second set of potential handover opportunities.

[0099] At least one metric may include reference signal received power and / or reference signal received quality.

[0100] According to the eleventh aspect, a computer program product stored on a medium which the apparatus may be made to perform any of the methods described herein is provided.

[0101] According to a twelfth aspect, an electronic device is provided which may include the apparatus described herein.

[0102] According to a thirteenth aspect, a chipset is provided which may include the device described herein.

[0103] Next, I will explain some examples for illustrative purposes, referring to the attached diagrams. [Brief explanation of the drawing]

[0104] [Figure 1] This is a schematic diagram of a 5G system. [Figure 2] This is a schematic diagram of the network device. [Figure 3] This is a schematic diagram of the user's equipment. [Figure 4] This diagram shows the signaling operation. [Figure 5]This is a diagram showing the measured configuration. [Figure 6] This diagram illustrates an exemplary handover opportunity. [Figure 7] This diagram illustrates an exemplary handover opportunity. [Figure 8] This diagram illustrates an exemplary signaling operation. [Figure 9A] This diagram illustrates an exemplary handover opportunity. [Figure 9B] This diagram illustrates an exemplary handover opportunity. [Figure 9C] This diagram illustrates an exemplary handover opportunity. [Figure 10] This diagram illustrates an exemplary handover opportunity. [Figure 11] This figure shows an exemplary operation that can be performed by the apparatus described herein. [Figure 12] This figure shows an exemplary operation that can be performed by the apparatus described herein. [Modes for carrying out the invention]

[0105] The following describes actions that can be taken to perform handover more efficiently in a wireless access network.

[0106] In the following examples, specific embodiments are described with reference to devices that can communicate via a wireless cellular system and mobile communication systems that provide services to such mobile communication devices. For brevity and clarity, such embodiments will be described below with reference to 5G wireless communication systems. However, it should be understood that such embodiments are not limited to 5G wireless communication systems and may also apply to other wireless communication systems, for example, the current 6G proposal, IEEE 802.11, etc.

[0107] Before going into detail about the examples, let's briefly explain the specific general principles of 5G wireless communication systems by referring to Figures 1-3.

[0108] Figure 1 shows a schematic diagram of a 5G system (5GS) 100. The 5GS may comprise a user equipment (UE) 102 (sometimes called a communication device or terminal), a 5G access network (AN) (which may be a 5G radio access network (RAN) or any other type of 5G AN, such as a non-3GPP interworking function (N3IWF) / trusted non-3GPP gateway function (TNGF) for untrusted / trusted non-3GPP access, or a wired access gateway function (W-AGF) for wired access) 104, a 5G core (5GC) 106, one or more application functions (AF) 108, and one or more data networks (DN) 110.

[0109] Figure 2 shows an example of a control unit for a communications system that is coupled to and / or controls, for example, a RAN node, such as a base station, gNB, central unit of a cloud architecture, or a node of the core network such as an MME or S-GW, a scheduling entity such as a spectrum management entity, or a station of an access system such as a server or host such as a device hosting an NRF, NWDAF, AMF, SMF, UDM / UDR, etc. The control unit may be integrated into a node or module of the core network or RAN, or it may be external. In some examples, the base station has a separate control unit unit or module. In other examples, the control unit may be another network element such as a radio network controller or spectrum controller. The control unit 200 can be configured to control communications within the service area of ​​the system. The device 200 includes at least one memory 201, at least one data processing unit 202, 203, and an input / output interface 204. Through the interface, the control unit can be coupled to the receiver and transmitter of the device. The receiver and / or transmitter may be implemented as a radio front end or a remote radio head. For example, the control unit 200 or processor 201 may be configured to execute appropriate software code to provide control functions. References to “code” herein are understood to mean software code, and vice versa.

[0110] Access system stations can be classified into two different types: distributed units (DUs) and centralized units (CUs).

[0111] A DU provides access node support to lower layers of the protocol stack (e.g., radio link control (RLC), media access control (MAC), and / or the physical layer protocol layer). Each DU can support one or more cells, and each cell can support one or more beams.

[0112] A CU can support multiple DUs and provides access node support to the upper layers of the protocol stack within the access node (e.g., Packet Data Convergence Protocol (PDCP), Service Data Adaptation Protocol (SDAP), and / or Radio Resource Control (RRC) protocol layers). The interface between the CU and DU is labeled as the F1 interface. There is one CU per gNB, and CUs belonging to multiple gNBs may be implemented using a shared hardware platform.

[0113] Next, with reference to Figure 3, which shows a schematic partial cross-sectional view of the communication device 300, possible wireless communication devices will be described in more detail. Such communication devices are often called user equipment (UE) or terminals. A suitable mobile communication device can be provided by any device capable of sending and receiving radio signals. Non-limiting examples include mobile stations (MS) or mobile devices such as mobile phones or so-called "smartphones," computers with wireless interface cards or other wireless interface equipment (e.g., USB dongles), personal data assistants (PDAs) or tablets with wireless communication capabilities, or any combination thereof. Mobile communication devices can provide data communication for transmitting communications such as voice, email, text messages, and multimedia. Thus, users can provide or receive a variety of services through the communication device. Non-limiting examples of these services include two-way or multi-way calls, data communications or multimedia services, or simply access to data communication network systems such as the Internet. Users may also be provided with broadcast data or multicast data. Non-limiting examples of content include downloads, television and radio programs, videos, advertisements, various alerts, and other information.

[0114] Wireless communication devices may be, for example, mobile devices, i.e., devices not fixed in a specific location, or they may be fixed devices. Wireless devices may or may not require human intervention for communication. As described herein, the term UE or “user” is used to refer to any type of wireless communication device.

[0115] The wireless device 300 may receive signals via an air interface or radio interface 307 through a suitable receiving device, and may transmit signals via a suitable transmitting device. In Figure 3, the transceiver device is schematically shown by block 306. The transceiver device 306 may be provided, for example, by a radio portion and an associated antenna arrangement. The antenna arrangement may be located inside or outside the wireless device.

[0116] A wireless device typically includes at least one data processing entity 301, at least one memory 302, and other possible components 303 for use in software code and hardware-assisted execution of tasks designed to be performed, such as accessing and controlling communication with access systems and other communication devices. The data processing, storage, and other related control devices may be located on a suitable circuit board and / or chipset. This functionality is indicated by reference no. 304. The user may control the operation of the wireless device by a suitable user interface, such as a keypad 305, voice commands, a touch-sensitive screen or pad, or a combination thereof. A display 308, speaker, and microphone may also be provided. Furthermore, the wireless communication device may include suitable connectors (wired or wireless) to other devices and / or suitable connectors for connecting external accessories such as hands-free devices.

[0117] The following explanation also provides illustrative examples referring to primary-secondary cells (PSCell), primary cells (PCell), and secondary cells (SCell). Below, we outline the characteristics of PSCells related to 5G New Radio, using the terminology used therein. However, it should be understood that the principles described here are not limited to such terminology and may apply to other systems with similar architectures. For example, in multi-radio dual connectivity (MR-DC), the primary cell (PCell) may be a Long-Term Evolution (LTE) cell (e.g., Evolved-Universal Terrestrial Radio Access-New Radio-dual connectivity (EN-DC)).

[0118] A PSCell is a type of cell currently defined in 5G new radio, along with primary cells (PCells), secondary cells (SCells), and special cells (SpCells). A PCell may be used as part of the initial access between the UE and the access network and is considered the main cell within a master cell group (MCG). A PSCell may be configured as part of a secondary cell group (SCG). SpCells and SCells may reside in at least one of the MCGs and SCGs.

[0119] Cells may be controlled by network nodes. New 5G radios have up to two different types of network nodes: master nodes (which provide control plane connectivity to the core network) and secondary nodes (which do not have control plane connectivity to the core network). It is understood that not all 5G system deployments will have master and secondary nodes. For example, master and secondary nodes may exist in a master node dual connectivity deployment but not in a standalone deployment. Both master and secondary nodes may provide user plane (e.g., data) connectivity to the core network. A master node may control a PCell. A master node may control at least one PSCell in addition to a PCell, but is not necessarily required. A secondary node may control at least one PSCell.

[0120] 3GPP has issued several releases (Rel.) to define operational communication protocols related to communication networks. Currently, goals and work have been set for Release 18 (Rel. 18).

[0121] Conditional mobility was introduced in 3GPP Rel-16 to improve the robustness of mobility. Conditional mobility involves providing the UE with at least one configuration to use for communicating with another cell after a handover to that cell has been performed, and at least one threshold or condition for determining when to perform the handover.

[0122] Therefore, as part of this conditional mobility functionality, the network can prepare multiple target cells to provide the UE with a conditional mobility configuration associated with mobility execution conditions. Thus, the decision to execute mobility is left to the UE, which is obligated to follow the conditional mobility configuration that defines when and how to execute mobility events. The conditional mobility configuration may be provided to the UE by a source cell (for example, by the UE's current serving cell). The conditional mobility configuration may be prepared by the source cell in conjunction with at least one target cell.

[0123] The preparation for conditional mobility (for example, a source cell communicating with at least one target cell to obtain a conditional mobility configuration to provide to the UE) may be triggered by mobility-related measurement events received by the source cell. For example, in the current 3GPP specification, these measurement events may be A3 / A5 measurement events in the case of handover. Whenever the configured execution conditions are met for any target cell (the process of determining which one is called the “evaluation phase”), the UE selects the corresponding target configuration and executes a mobility procedure to enable service provision through the selected target cell. The execution of the mobility procedure is also called the “execution phase”.

[0124] There are several types of conditional mobility events. Of these, conditional handover (CHO), conditional primary / secondary cell (PSCell) addition (CPA), and conditional PSCell modification (CPC) are described below. The signaling procedure for performing a conditional handover is described in section 9.2.3.4.2 of TS38.300.

[0125] Mobility management is another scheme related to mobility operations. Mobility management is a scheme to ensure continuity of service during mobility operations (e.g., cell changes, cell additions, handovers, etc.). This may include minimizing call disconnections, radio link failures (RLFs), unnecessary handovers, and ping-pong between accesses provided by different cells. Furthermore, for applications characterized by stringent quality of service (QoS) requirements (e.g., reliability, latency, etc.), where quality of experience (QoE) is sensitive to handover performance, mobility management attempts to avoid failed handovers and reduce latency during handover procedures.

[0126] To address at least part of this problem, research is provided on enhancing data collection for new radio (NR) and enhanced dual connectivity (EN-DC), with the general objective of studying high-level principles for enabling AI in radio access networks (RANs) and a functional framework (including AI functions and inputs and outputs) to enable the deployment of ML algorithms at the RAN level. One of the use cases defined in 3GPP TR37.817 Section 5.3, "mobility optimization," aims to improve the mobility performance of UEs through the use of AI / ML solutions.

[0127] More specifically, Rel-18 has been commissioned to conduct research on artificial intelligence (AI) / machine learning (ML) for the NR air interface. This research has multiple objectives.

[0128] For example, several potential use cases (as shown below) have been identified, and one of the objectives of this study is to examine the AI / ML 3GPP framework for air interfaces corresponding to each use case in terms of aspects such as performance, complexity, and potential impact on specifications.

[0129] The use cases we will focus on are: ○ Enhanced channel status display feedback (e.g., reduced overhead, improved accuracy, prediction, etc.) ○ Beam management, for example, beam prediction in the time domain and / or spatial domain to reduce overhead and delay, and improvement of beam selection accuracy. ○Improved positioning accuracy in various scenarios, such as when NLOS conditions are severe. An initial set of use cases related to this, This includes a subsequent set of use cases, each with a representative sub-use case for characterizing the use case and evaluating its baseline performance. The AI / ML methods applied to the representative sub-use cases may be diverse enough to support the various requirements of the gNB-UE collaboration level.

[0130] Another objective of this study is to define the AI / ML models used, including terminology and explanations to identify common and specific characteristics of the framework survey.

[0131] This may comprise a characterization phase (where the complexity associated with the AI / ML-related algorithms is defined) and a collaboration phase (where varying degrees of collaboration between the UE and access nodes for various use cases are identified).

[0132] The characterization stage may include both model generation (e.g., model training (including input / output, pre-processing / post-processing, and online / offline if applicable), model validation, and model testing) and inference operations (e.g., input / output, pre-processing / post-processing).

[0133] During the collaboration phase, various levels of collaboration between the UE and access nodes related to the selected use case can be identified. For example, if there is no collaboration between the UE and access nodes for the selected use case, only implementation-based AI / ML algorithms may be provided without information exchange. In contrast, if there are various levels of collaboration between the UE and access points, separate ML operations or joint ML operations may be provided.

[0134] Other factors related to AI / ML models and algorithms may also be considered.

[0135] For example, the lifecycle management of AI / ML models may be characterized (e.g., model training, model deployment, model inference, model monitoring, model updating, etc.).

[0136] Another factor to consider may be the datasets used for training, validation, testing, and inference.

[0137] Another element that may be identified is a common notation and terminology for AI / ML-related functions, procedures, and interfaces.

[0138] For the use cases considered in this study, the potential impact of 3GPP specifications may be taken into account with the aim of establishing a common framework. This may be considered from both a physical (PHY) layer perspective and a higher-layer protocol perspective.

[0139] The physical layer aspects may be considered in relation to, for example, potential specifications for AI model lifecycle management and dataset construction for training, validation, and testing selected use cases. Furthermore, both use case and collaboration level-specific impacts on the 3GPP specification may be considered, such as new signaling, features for training and validation data support, provision of supporting information, measurement definitions, and feedback behavior.

[0140] In terms of the protocol's aspects, for example, aspects related to function indication, configuration and control procedures (training / inference), data and AI / ML model management, and the impact of collaboration level-specific specifications for each use case may be considered.

[0141] As part of the above initiatives, 3GPP is discussing a model that performs time-domain predictions of beam reference signal received power (RSRP) and beam identifier.

[0142] Next, we consider several mechanisms used to initiate handover-related procedures, whether through network initiation / instruction or conditional mobility events.

[0143] Regardless of the communication technology (2G, 3G, 4G, or 5G), the mobility / handover decision of whether a mobile device is to be handed over can be made by the access point based on measurement reports received from the UE. There are multiple measurement metrics (e.g., reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-interference noise ratio (SINR)), multiple timings (e.g., periodically, event-triggered, etc.) and multiple methods by which the UE may measure the signal quality of its serving cell and adjacent cells. For example, the access node may determine from the measurement report that the UE needs to be handed over from its current serving cell to a target cell that can provide better service to the UE than the serving cell, and signal the UE to perform that handover. As another example, the access node may determine that the UE is likely to hand over in the near future. The access node may then provide the UE with some monitoring and execution conditions to determine when the UE will hand over to at least one of several target cells as part of a conditional mobility event.

[0144] In an ideal scenario, the access point would allow the UE to report the signal quality of the serving cell and adjacent cells, triggering the UE to perform a handover based on a single measurement. However, in reality, unnecessary handovers, such as ping-pong, can lead to overload conditions.

[0145] To minimize the possibility of such situations, the 3GPP specification proposes a set of predefined measurement reporting mechanisms that must be implemented by the UE. The types of predefined measurement reports are called "events." The types of "events" that the UE is configured to report are specified by radio resource control (RRC) signaling messages sent to the UE by the access point.

[0146] 3GPP TS38.331 specifies the following event types for 5G NR: ●Event A1 (Serving cell status improves to better than the threshold) ● Event A2 (Serving cell status deteriorates below threshold) ●Event A3 (The state of the adjacent cell becomes better than the state of the SpCell by an offset value exceeding that value) ●Event A4 (The state of adjacent cells is better than the threshold) ●Event A5 (The state of the SpCell deteriorates below the first threshold (threshold1), and the state of the adjacent cell improves above the second threshold (threshold2))

[0147] In a mobility scenario, a UE may be handed over from the first cell to the second cell and then immediately returned to the first cell. Alternatively, a UE may be handed over to the second cell and then immediately to the third cell. The handover process typically involves a downtime, which arises from the time it takes for the UE to synchronize to the new cell and process RRC reconfiguration messages. Handovers are also associated with signaling between the UE and the network, signaling between nodes within the network, and processing tasks within the network.

[0148] In addition to existing mobility procedures, recent 3GPP research is also considering Layer 1 / Layer 2 (L1 / L2) Triggered Mobility (LTM) procedures. Layer 1 refers to the physical layer, and Layer 2 refers to the Media Access Control (MAC) layer.

[0149] LTM is one of the mobility enhancement goals planned for Rel.18. LTM introduces new techniques to reduce handover downtime, but may also increase the number of handovers compared to BHO.

[0150] In contrast to Layer 3 (L3) mobility procedures (e.g., network-triggered mobility procedures) where handover between two cells is determined by the Radio Resource Control (RRC) layer, LTM is performed by the MAC layer. Therefore, in the gNB's CU-DU model, it terminates at the Distributed Unit (DU).

[0151] Figure 4 shows exemplary signaling that can be performed for LTM from a serving cell in the first distributed unit (DU1) to a target cell in the second distributed unit (DU2). This scenario is called the inter-DU-intra-CU scenario. A similar signaling diagram is applied to intra-DU-intra-CU cell change where DU1 is the same distributed unit as DU2.

[0152] Figure 4 shows the signaling that can be performed by UE401, the first DU402, CU403, and the second DU404.

[0153] Numbers 4001-4009 refer to the "preparation phase" of LTM. During the preparation phase, the network determines the configuration of potential target cells for LRM based on measurement reports received from the UE.

[0154] During 4001, UE401 signals to the first DU402. This signaling may include a measurement report. The measurement report may include information specified in the measurement report configuration. The measurement report may include indications of measurements taken for the UE's radio environment that indicate the state of that radio environment. This report may be triggered because the signal provided by an adjacent cell is better than the signal provided by the serving cell, indicating that the UE is within the cell boundary area.

[0155] The settings for RRC measurement, measurement trigger, and measurement report configuration are described in Section 5.5.1 of 3GPP TS38.331.

[0156] A graphical overview of the configuration hierarchy is explained with reference to Figure 5.

[0157] Figure 5 shows that the measurement configuration consists of a measurement object, a report configuration, a measurement identifier (which includes a list of combinations of measurement objects and report configurations), a quantity configuration (which specifies the quantity to be measured and the layer 3 filtering coefficient), and an indication of at least one measurement gap.

[0158] Each measurement object may include a target cell frequency, a target reference signal, and a list of blacklisted and / or whitelisted cells.

[0159] Each report configuration may include a report volume that includes the event type, the number of reports (e.g., synchronization signals (SS), physical broadcast channels (PBCH), and / or channel status information reference signals), the reporting criteria (e.g., periodic or event-based), and the interval.

[0160] During 4002, the first DU402 forwards the measurement report received during 4001 to CU403.

[0161] During 4003, CU403 signals to the first DU402. This signaling may include a UE context setup request. The purpose of this UE context setup request is to establish a UE context (e.g., security key, UE functionality, etc.) with respect to the UE in the first DU402.

[0162] During 4004, the first DU402 signals to CU403. This signaling may include a UE context setup response. This signaling may include a DU-to-CU container for communication between the DU and the CU.

[0163] During 4005, CU403 signals to a second DU404. This signaling may include a UE context setup request. The purpose of this UE context setup request is to establish a UE context in the second DU404 with respect to the UE.

[0164] During 4006, the second DU404 signals to CU403. This signaling may include a UE context setup response. This signaling may include a container from DU to CU.

[0165] During 4007, CU403 generates a Radio Resource Control (RRC) reconfiguration for UE401. This RRC reconfiguration may include a measurement report configuration for layer 1 cell change operations and a configuration for any prepared target cells on which those measurements will be performed. This generation may be based on the UE context setup response received during 4004 and 4006.

[0166] During 4008, CU403 signals UE401. This signaling may include the RRC reconfiguration that occurred during 4007.

[0167] During 4009, UE401 signals CU403 to indicate that the UE is applying the RRC reconfiguration received during 4008.

[0168] During 4010, UE401 signals to the first DU402. This signaling may include a measurement report generated according to the RRC reconfiguration received during 4008. 4010 may be performed repeatedly (for example, if the RRC reconfiguration is configured to cause UE401 to generate periodic measurement reports).

[0169] Based on at least one measurement report received during 4011 and 4010, the first DU402 determines that there is a target candidate cell with better radio link beam measurements than the UE's current serving cell (e.g., L1-RSRP of target beam measurement > L1-RSRP of serving beam measurement + e.g., Time-to-Trigger (TTT) time offset), and signals a MAC control element (MAC CE) or L1 message to UE401. This signaling to the UE acts as a trigger, causing UE401 to perform a cell change operation to the target candidate cell.

[0170] During 4012, a handover is performed, and UE401 is handed over from the current serving cell, provided by the first DU402, to the target cell.

[0171] The main advantage of LTM compared to baseline and conditional handovers is that it significantly reduces interruptions during handover because the UE does not need to perform higher-layer reconfiguration (e.g., RRC reconfiguration and / or Packet Data Convergence Protocol (PDCP) reconfiguration). Furthermore, in some scenarios, the UE can perform a more generalized handover scheme (known as Random Access Channel (RACH)-less) than those typically used to connect to the target cell.

[0172] In Frequency Range 2 (FR2), a frequency range defined by 3GPP to occupy a portion of the frequency spectrum above 6 GHz, channel states may change more rapidly compared to Frequency Range 1 (FR1), also defined by 3GPP. This can lead to more frequent handovers for UEs operating in FR2 than for UEs operating in FR2. Frequent handovers increase the number of unnecessary handovers.

[0173] Therefore, avoiding handovers reduces interruptions and lowers the cost of signaling and processing in the network.

[0174] Figure 6 shows RSRP traces collected from LTM mobility simulations, illustrating the problem of unwanted handovers leading to unnecessary gaps. In this figure, the x-axis corresponds to time, and the y-axis corresponds to cell intensity. Cell intensity can be measured, for example, as RSRP.

[0175] The simulation scenario shown in Figure 6 consists of an UE moving at a speed of 120 km / h and a carrier frequency of 30 GHz. Handover is initiated when it is determined that the quality of the adjacent beam received by the UE is at least 3 dB better than the UE's serving beam.

[0176] In Figure 6, RSRP traces the beam identifiers of three cells recorded at the serving base station in the system-level simulator. Gaps in the trace indicate where handovers occurred and measurements could not be collected. Figure 7 shows that two handovers occurred within 400 milliseconds. Therefore, it appears that at least the first handover could have been avoided.

[0177] It is useful for wireless access network entities to be able to predict and avoid unnecessary handovers when they are parameterized as "unnecessary" by the network.

[0178] To address at least one of the above issues, we propose the following mechanism to reduce the likelihood of unnecessary handovers.

[0179] In particular, the following focuses on configuring the UE using a predictive window (for example, a period of time) in which the UE may perform a handover from a source access node to multiple target access nodes. The UE is provided with a so-called "feasibility configuration" (also referred to herein as "feasibility conditions") that can be used to identify these multiple handover times. The feasibility configuration may further (in some examples) be used by the UE to identify which of these multiple handovers are unnecessary and therefore may not be performed. In other words, the feasibility configuration may include at least one condition (or set of conditions) that can be used to identify those multiple future handover opportunities within the predictive window and / or to determine which of those handovers may be considered unnecessary.

[0180] The network may provide indicators of different time periods, for example, precise numerical values ​​in units of time, or it may indicate that the UE can select and arbitrarily determine a time period, or it may indicate that the UE can select and arbitrarily determine a time period of at least a minimum duration.

[0181] In another embodiment, the duration of the prediction window is determined by the UE. For example, in the FR2 setting, at 120 km / h, the appropriate duration is found to be 400 milliseconds.

[0182] In another embodiment, the network constitutes a minimum duration.

[0183] In some examples, the feasibility configuration extracts relevant parameters to detect unnecessary handovers in the future, but the final evaluation of which handovers are unnecessary is left to the serving access node.

[0184] The UE performs predictions of conditions and events described by the feasibility configuration provided to the UE by the network. How the UE achieves the predictions of conditions and events or key markers described by the feasibility configuration is left to its execution.

[0185] In one example, the UE may predict the RSRP window and derive results based on that RSRP window. This is explained below in relation to creating the RSRP window prediction from which key markers (e.g., events) are derived.

[0186] The feasibility configuration / condition may include at least one of the following: 1. The minimum connectivity condition for a serving cell, which can be expressed as an absolute threshold or an offset to an adjacent cell. The cell connectivity condition may also be a condition (e.g., a criterion or set of criteria) that must be met for the UE to consider the cell strong enough to connect to. 2. Rules for the UE to select a target cell. For example, the selected target cell may be the cell that is predicted to have the longest connectivity period immediately after the serving cell ceases to meet the minimum connectivity requirement. This is explained below in relation to Figure 7. Figure 7 shows a window spanning time periods A to B along the x-axis, with the power and / or quality of the signal received by the user equipment represented by the y-axis. In Figure 7, the threshold is represented by a flat line, the current serving cell is represented by the first curve 701, the potential target cell is represented by the second curve 702, and the second potential target cell is represented by the third curve 703. The x-axis represents time. In Figure 7, the serving cell 701 is considered not to be providing minimum connectivity from time point C onward, when it falls below the threshold. Between time point C and time point B, the second potential cell 703 is determined to provide the longest connectivity to the UE. Other rules, including the relative strength between potential targets, may also be considered when making selections and / or predictions. The point at which the signal strength and / or quality of one cell switches from being lower than another cell to being higher than another cell (or vice versa) is known as an event. An event might be, for example, an A1 event and / or an A3 event. The information shown in Figure 7 (e.g., predictions of signal strength and / or signal quality) may be obtained by the UE in at least one of several different ways. For example, the UE may use current signal strength information and mobility information related to how the user equipment moves to the access node providing the cell in order to predict how the current signal strength will change over time (e.g., within a duration of A-B). Furthermore, the UE may use historical signal strength information to predict how the current signal strength will change over time. The UE may perform calculations itself to obtain these predictions, or may outsource these calculations to another entity (e.g., a cloud-based server). The predictions may be made using machine learning and / or artificial learning algorithms. In such a case, when the UE itself performs these predictions, the UE may obtain a trained model for performing these predictions. The UE may partially train such a model using measurement information obtained locally by the UE. The time instance (e.g., time A) to start the prediction and / or the duration of the prediction window may be dynamically requested by the network. The time period from A to B may represent a period that has not yet occurred. In other words, the range of the prediction window may relate to future time. Time A may represent the current time or a future time. 3. Rules for selecting the target handover time instance. Since the prediction may be unstable, the execution of the condition may be defined to occur at a specific time. For example, it may be defined as abs(predicted time - current time) < eps, where eps may be the measurement interval.

[0187] In one embodiment, the network configures the minimum duration (not shown) for which a prediction is required and provides the indicator to the UE. For example, if the UE cannot perform a prediction for the indicated duration received from the network due to reasons such as insufficient computing power, the UE may choose not to perform the prediction or not to deliver the prediction. Otherwise, the UE may determine the duration A - B for which to perform the prediction. The UE may determine the duration A - B indicated by the network. The UE may determine a duration A - B that satisfies the minimum duration indicated by the network.

[0188] In one embodiment, the UE determines the duration A - B, for example, based on the geographical speed. For example, in the FR2 setting, when the speed is 120 km / h, it can be seen that the appropriate duration is 400 milliseconds.

[0189] The above configuration rules may also identify when potential handover events may occur by reusing the parameterization of existing trigger conditions (for example, event conditions such as A1 and A3 as currently defined in the 3GPP specification) which include any combination of those trigger conditions.

[0190] For example, existing trigger conditions for triggering a handover event (e.g., an A3 event trigger condition) may be used to compare the strength of a serving cell with the strength of its neighboring cells. Here, the configuration rules for an A3-based handover event may be used to compare a hypothetical future service (e.g., a candidate cell and / or target cell) with the strength of its neighboring cells.

[0191] More specifically, an A3 event includes a handover event that is triggered when an adjacent cell becomes better than the UE's current serving cell by an offset amount, and the offset may be positive or negative. In other words, an A3 event-based handover is triggered when a predetermined set of conditions is met. The above configuration rules may determine the time at which the predetermined set of conditions is expected to be met and identify that time as a potential future handover instance within the prediction window. The UE may apply the same predetermined set of conditions to predict events occurring between multiple cells within the prediction window, including between two adjacent cells and / or between a serving cell and an adjacent cell. The cells evaluated within this prediction window may be restricted in some way. For example, cells may be limited to serving cells, and adjacent cells may be limited to serving cells. The cells evaluated within the prediction window may be determined by the UE. The cells evaluated within the prediction window may be determined by the serving cell and signaled to the UE.

[0192] Once the UE determines key outcomes, such as potential future handover instances, within the prediction window, the UE notifies the network of its decision via a report. The network may use the report to prepare the selected target cell within the network and make it available to the UE during the selected time instance.

[0193] As time passes and window predictions are updated, the target time and target cell may change. The UE may notify the network (the UE's serving cell) of these changes.

[0194] The serving cell may signal the UE to perform a handover when the target handover time arrives.

[0195] These principles will be explained with reference to the following example.

[0196] Figure 8 shows the signaling that can be performed between UE801, serving access node 802, and target access node 803.

[0197] During 8001, the serving access node 802 (which provides a serving cell to the UE) signals to UE801.

[0198] This signaling from 8001 may configure the length of the prediction window for UE801. The length of the prediction window may be set by the serving access node 802, for example, based on past measurement time when the UE remained within the cell. The length of the prediction window may also be set by the serving access node 802, based on system-level simulations performed by the network. The serving access node 802 may select a fixed value and / or a pre-configured value (for example, a fixed value of 500 milliseconds) for the length of the prediction window. This value may represent a window duration sufficient to identify potential unwanted handovers of fast-moving UEs.

[0199] The signaling of 8001 may configure the UE with at least one parameter for making predictions within a time window (hereinafter simply referred to as the "window"). For example, the signaling may include a minimum window prediction length and / or a metric predicted within that window. The serving access node 802 may configure the UE to predict the beam's RSRP within the window length, for example.

[0200] During 8002, the serving access node 802 signals to UE801. This signaling may configure the UE to configure at least one rule for extracting actions from a window. For example, the signaling of 8002 may include a feasibility configuration. In other words, the signaling of 8002 may indicate to the UE what information should be extracted from the prediction of beam characteristics received within the prediction window. For example, the feasibility configuration may instruct the UE to determine each time instance in which the received beam power and / or quality of a particular cell (e.g., a serving cell and / or a target cell) is above and / or below a predetermined threshold, and / or the received beam power of another cell is above or below a predetermined threshold.

[0201] The executable configuration may include at least one of several different rules that the UE applies in relation to the window.

[0202] As a first example, a feasibility configuration may comprise a combination of existing (legacy) mobility triggers and rules for how to derive a target cell. For example, a UE may be configured to use at least one of the A1 event (when the signal received from a cell is better than a threshold) and / or A2 event (when the signal received from a cell is worse than a threshold) to mark all cells as feasible. The target cell, which is determined to have the longest feasibility, is then selected for use after the current serving becomes unavailable to the UE. An A3 threshold between the serving cell and the target cell may be used during the prediction window to determine the time instance of the handover.

[0203] In this example, the A1, A2, and / or A3 thresholds within the prediction interval may not only compare the received signal level of the serving cell to the threshold, but may also compare a target candidate for the received signal level to the threshold or another adjacent cell candidate.

[0204] For example, the A3 event definition in TS38.331 5.5.4.4 includes various parameters for the input conditions. Mn+Ofn+Ocn-Hys>Mp+Ofp+Ocp+Off In the above equation, ●Mn is the measurement result of adjacent cells without considering the offset. ●Ofn is the measurement object-specific offset of the reference signal of the adjacent cell (for example, offsetMO defined in measObjectNR corresponding to the adjacent cell). ●Ocn is the cell-specific offset of the adjacent cell (for example, cellIndividualOffset defined in measObjectNR corresponding to the frequency of the adjacent cell), and is set to zero if not configured for the adjacent cell. ●Mp is the measurement result of SpCell without considering the offset. ●Ofp is the measurement object-specific offset of the SpCell (for example, offsetMO defined in the measObjectNR corresponding to the SpCell). ●Ocp is the cell-specific offset of the SpCell (for example, cellIndividualOffset defined in the measObjectNR corresponding to the SpCell), and is set to zero if not configured for the SpCell. ●Hys is the hysteresis parameter for this event (i.e., the hysteresis defined in the reportConfigNR for this event). ●Off is the offset parameter for this event (for example, a3-Offset defined in the reportConfigNR for this event). ●Mn and Mp are expressed in dBm for RSRP and in dB for RSRQ and RS-SINR. Ofn, Ocn, Ofp, Ocp, Hys, and Off are expressed in dB.

[0205] The variables on the left refer to the parameters of the adjacent cell, while the variables on the right (Mp, Ofp, Ocp) refer to the serving cell (SpCell) and the A3 offset (Off) configured therein. Reusing the parameters of this event for the purpose of A3 prediction events means that Mp, Ofp, and Ocp refer to the predicted values ​​of potential future serving cells. Since there may be multiple possible future serving cells, these parameters apply to all possible candidates.

[0206] As a second example, the feasibility configuration may include a minimum connectivity condition for a serving cell, which can be expressed as an absolute threshold or as an offset to an adjacent cell. The feasibility condition may reuse or combine parameterizations of existing trigger conditions (e.g., trigger conditions associated with various events such as A2 events, A3 events, etc.). For example, the definition of an existing trigger A2 ("service provision deteriorates below threshold") may be applied to a forecast window, and the cell will only (strictly speaking) virtually provide service (e.g., the forecast window considers what would happen if a handover from a serving cell to an adjacent cell occurred at some point within the forecast window).

[0207] This will be explained with reference to Figures 9A and 9B.

[0208] Figure 9A shows how the RSRP of serving cell 901, the first target cell 902, and the second target cell 903 changes during the window. The flat line represents the threshold RSRP level (which may be set as an absolute value, e.g., -80 dBm). The RSRP level of a serving cell may fall below the threshold in time instance C (within the duration of the time window). In this example in Figure 9A, the minimum connectivity requirement for the serving cell is the RSRP value.

[0209] Figure 9B shows how parameters like RSRQ for serving cell 901', first target cell 902', and second target cell 903' change during the window. The flat line represents the threshold level for RSRQ (which may be set in absolute value). The RSRQ level of a serving cell may fall below the threshold in time instance C (within the duration of the time window). In this example in Figure 9B, the minimum connectivity condition for the serving cell is the RSRQ value. The RSRQ value may be defined, for example, as the sum of the RSRP ratio of the beam being evaluated and the RSRP values ​​of all other beams belonging to different cells. The threshold for this RSRQ measurement may be set to the parameter Qout configured by the network and / or operator.

[0210] As a third example, the feasibility configuration may include rules for selecting a target cell. For instance, the UE may be configured to use the rules provided in the feasibility configuration to select a target cell (and autonomously initiate a mobility procedure to the target cell). However, in some examples, it is understood that the UE simply provides the source cell with an indication of its discovery results.

[0211] For example, immediately after a serving cell ceases to meet the minimum connectivity requirement, the cell with the longest connectivity duration may be selected as the target cell. In other words, if a threshold is used for the minimum connectivity requirement, a rule may be provided to determine which of the candidate target cells has the longest connectivity starting from C.

[0212] As another example, an estimate of the absolute performance of candidate target cells is used to select a target cell. The absolute performance values ​​for which a candidate is selected may be aggregated over the time period for which the candidate target cell is selected to function as a serving cell for the UE. The candidate target cell may be selected as the candidate cell that is determined to have the best performance as a serving cell to the UE.

[0213] An example of this is provided below in relation to Figure 9C. Figure 9C shows how parameters such as RSRQ for serving cell 901'', first target cell 902'', and second target cell 903'', change during the window. The flat line represents the threshold level of RSRQ (which may be set in absolute value). The RSRQ level of a serving cell may fall below the threshold in time instance C (within the duration of the time window). In this example of Figure 9C, the minimum connectivity condition for a serving cell is a value such as RSRQ. The RSRQ value may be defined, for example, as the sum of the RSRP ratio of the beam being evaluated and the RSRP values ​​of all other beams belonging to different cells.

[0214] In the example in Figure 9C, the evaluation can be performed as follows:

[0215] Firstly, it is determined that serving cell 901'' will become unusable from C onward.

[0216] Secondly, candidate target cells 902'' and 903'' are determined to satisfy the minimum connectivity requirements for functioning as serving cells to the UE.

[0217] Thirdly, the handover time between the serving cell and each of the candidate cells determined in the previous step is determined. For example, in this example, the handover time for handing over from serving cell 901'' to the first target cell 902'' is time D, and the handover time for handing over from serving cell 901'' to the second target cell 903'' is E.

[0218] Fourth, once the first target cell 902'' is selected for consideration, the performance measurement is determined as a1 + a2 ... + a8 - a4.

[0219] Fifth, when the second target cell 903'' is selected for consideration, the performance measurement is determined as a1 + a2 + ... + a8 - a2 - a3.

[0220] Sixth, if a2+a3>a4, then the first target cell 902'' is determined to be selected as the target cell. In other words, the first target cell 902'' is selected if the difference in a metric like RSRQ between the first target cell at its strongest and the next strongest when integrated over time is greater than the difference in a metric like RSRQ between the second target cell at its strongest and the next strongest when integrated over time.

[0221] In this example, at time A, a2+a3>a4, so it is decided to hand over to the first target cell at time D. As the window progresses and a4>a2+a3 becomes greater than a4, the second target cell 903'' is selected instead of the first target cell 902''. In such a case, no handover is performed at that point.

[0222] Another method for measuring performance is estimated throughput. Estimated throughput may be based, for example, on an ideal / Shannon mapping from RSRQ estimates to throughput.

[0223] As a fourth example, the feasibility configuration may include rules for selecting a target handover time instance.

[0224] For example, the handover time may be selected as the point at which the predicted signal of the target cell becomes better than the predicted serving cell by more than an offset amount. The evaluation of potential handovers within the prediction window may include multiple hypotheses about which cell will provide service. That is, when evaluating the prediction window, all potential handover times (e.g., all intersection points of the predicted cell strength curves) may be obtained.

[0225] Since the prediction may be unstable, at runtime, conditions may be defined to minimize the possibility that a handover is performed as a result of an incorrect prediction. For example, this condition may be defined as abs(predicted time - current time) < eps, where eps is the measurement interval. Depending on the implementation of the prediction, the abs() operation may not be necessary.

[0226] As a fifth example, the feasibility configuration may include rules for deriving cell feasibility from beam measurements. The cell strength may be derived from the beam strength of the cell. The cell strength may be set, for example, as the maximum cell beam strength or as the average of the N best beams of the cell, where N is a parameter configured by the network.

[0227] The feasibility configuration may include a method for deriving a desired result in two steps. In the first step, the UE is instructed to predict a window for identifying the relative strength of the cell and a window for predicting where the cell exceeds an absolute threshold. These two prediction windows are sufficient for the UE to determine possible HO times with parameterized offset = 0 and Time-to-Trigger (TTT) = 0 in the second step.

[0228] The configuration received during 8002 may define what the UE delivers as a feasibility assessment during 8008. The UE may be configured to deliver the assessment results.

[0229] For example, the UE may be configured to signal predicted event triggers (such as predicted A3 or A2 if a conventional trigger is used in the configuration) to the network during 8008. This is illustrated in the following example of how to specify conditions such as A3 in the prediction window in the RRC specification.

[0230] A predicted A3 event relates to an event in which an adjacent candidate cell is predicted to be better by a threshold amount than the signal predicted to be provided by the PCell and / or PSCell. The included predictedEventA3 may apply to possible future serving cell and / or adjacent cell pairs. In particular, the information element "ReportConfigNR" currently defined in the new radio may be extended to the new report types shown in bold below. JPEG2026509757000002.jpg165170

[0231] If configured by a network, the UE may be able to evaluate a predicted event (e.g., A3, indicated by predictedEventA3 within the prediction window specified by predictionWindowDuration). The evaluation begins by considering the current pair of PCells as the source and target cells (measured based on the corresponding measObjectNR). Once a given predicted event (e.g., A3) is deemed to have been met, the UE continues evaluating the given predicted event (e.g., A3) for the remainder of the prediction window by considering the target cell as the new source cell and forming a PCell pair of source and target cells to continue the evaluation. All such beam pairs detected by the UE within a given prediction window may be reported to the network during 8008. For each such reported pair, the UE may also report the predicted time at which A3 would be triggered and the predicted duration of stay. The predicted duration of stay may be calculated by the UE as the time period measured between PCell changes within a given prediction window.

[0232] As another example, a UE may be configured to signal to the UE an indication of a cell that is available to be used as a serving cell after the UE's current serving cell becomes unavailable.

[0233] As another example, the UE may be configured to signal indications for separate windows within a prediction window in which different target cells can be selected as serving cells by the UE. Windows that satisfy multiple conditions for the cells being evaluated are described below.

[0234] Note that while the UE may be configured to provide the network with such a report when the network performs its final evaluation and decides which target cells to select as handover targets, this is not always the case.

[0235] Therefore, the UE may be configured to provide the network with a list of cells identified as potential targets (and their respective predicted handover times). Selected target cells can be prioritized, and those cells can be skipped. Optionally, and alternatively, the UE may autonomously determine the next target cell within a specific time window and target handover time. This latter signaling may utilize less bandwidth than when the network makes a final decision and is suitable for autonomous (e.g., conditional handover style) handover procedures, as well as network decision handovers.

[0236] During 8003, UE801 signals to the serving access node 802. This signaling may include a cell edge measurement report. The cell edge measurement report may be configured before, during, or after 8001, for example, using a known mechanism. For example, the cell edge measurement report may be configured so that an A3 event is currently set.

[0237] During 8004, the serving access node 802 signals to the UE. This signaling may include an instruction to the UE to start the window prediction mechanism according to the configurations of 8001 and 8002.

[0238] During 8005, the UE implements a prediction window. This varies depending on the implementation, but examples of when a prediction window may be implemented are shown below.

[0239] In this example, the UE performs RSRP predictions for various reference signals within a time period defined by a window. This may be done, for example, using a convolutional long-term short-term memory (neural network type) (LSTM-RNN), taking historical RSRP sequences and beam identifier sequences as input (for example, using RSRP measurements collected over time by the UE). The model used for prediction may be provided to the UE by the network. The RSRP prediction window may consist of a set of predicted RSRP sequences for different cells. Thus, the input to the model may consist of each sequence of RSRP associated with multiple cells.

[0240] As an example, the inputs and outputs of this convolutional LSTM-RNN are as follows. input: - Sequence of previously recorded RSRP values - Sequence of beam identifiers recorded in the past output: - Time sequence of predicted future RSRP values ​​for different cells - Time sequence of predicted future beam identifiers for different cells

[0241] It is understood that "past" and "future" may or may not encompass a continuous period of time within the current time window.

[0242] This convolutional LSTM-RNN neural network may be trained within a specific coverage area. For example, the neural network may be trained when the UE is at the edge of a cell. The neural network may be retrained to fit a different coverage area. The output of the LSTM-RNN computation may be input to the UE.

[0243] During 8006, the UE determines the validity of the 8005 prediction (for example, the UE determines the confidence level of the 8005 prediction). How the UE does this varies by implementation, but at least one possible example is shown below.

[0244] During 8006, the UE performs a reliability assessment of the prediction for 8005. The UE may do this by predicting a past window and comparing it to the observed measurements. The UE may calculate the confidence as the percentage of samples that fall within a 1 dB margin.

[0245] The UE may be configured to evaluate the prediction according to the feasibility condition only when the minimum confidence level is reached. The minimum confidence level may be a value of 95%.

[0246] During 8007, the UE determines and evaluates the results of the feasibility configuration. This varies by implementation, but an example of how this can be done is shown below with reference to Figure 10. In this example in Figure 10, the UE evaluates the various conditions included in the feasibility configuration and then distributes an indication to the network of the time period during which the conditions are met.

[0247] Figure 10 shows how metrics such as RSRP or RSRQ for serving cell 1001, first target cell 1002, and second target cell 1003 change during the window. The flat lines represent threshold levels such as RSRP / RSRQ.

[0248] During this example, the RSRP / RSRQ level of the serving cell may fall below the threshold in time instance C, the RSRP / RSRQ level of the first target cell 1002 may be greater than the RSRP / RSRQ level of serving cell 1001 in time instance E, the RSRP / RSRQ level of the second target cell 1003 may be greater than the RSRP / RSRQ level of serving cell 1001 in time instance D, the RSRP / RSRQ level of the second target cell 1003 may be greater than the RSRP / RSRQ level of the first target cell 1002 in time instance G, the RSRP / RSRQ level of the second target cell 1003 may be greater than the threshold level in time instance F, and the RSRP / RSRQ level of the first target cell 1002 may be less than the threshold level in time instance H. All of these time instances are within a window.

[0249] Referring to Figure 10, the UE may determine the following using the time instance predictions indicated above: ●Period during which the threshold is exceeded: Serving cell 1001: up to C; First target cell 1002: up to H; Second target cell 1003: from F to H ●Comparison of serving cell 1001 and the first target cell 1002: E; Comparison of serving cell and the second target cell 1003: D ●Comparison of the first target cell 1002 and the second target cell 1003: G

[0250] Based on that information, the network can determine that the second target cell 1003 is the desired target.

[0251] UE801 may further provide indications of which cell is strongest (including at what time).

[0252] During 8008, UE801 signals to serving access node 802.

[0253] This signaling may also indicate that the UE801 has performed its evaluation.

[0254] The information provided in signaling may vary depending on the type of mobility operation being performed.

[0255] For example, generally speaking, there may be both network-controlled mobility events and UE-controlled mobility events.

[0256] With respect to network-controlled mobility events, the UE may be configured to provide the serving access node with information that indicates the values ​​of measurements collected by the UE. This information may include information that enables the serving access node to determine the UE's potential handover target cells. For example, this information may indicate potential handover target cells at future times, as well as / or cells that are providing the UE with a reference signal having signal power and / or quality greater than a predetermined threshold, as well as / or cells that are providing the UE with the strongest reference signal at different times or under different circumstances, allowing the serving access node to derive potential handover targets. In this case, the network determines the handover targets and handover times and sends a handover command to the UE at the determined handover time.

[0257] For UE-controlled mobility events (e.g., conditional handovers), the UE identifies at least one potential target cell as a potential handover target to the network. The network then prepares those identified target cells for handover to the UE and provides the UE with the respective execution conditions for handover to each of those target cells. These execution conditions are also called A3 triggers. When at least one execution condition is met, the UE can autonomously initiate a handover to each target cell associated with that at least one execution condition, without additional signaling from the serving access node. In this case, the UE may identify potential target cells using signal variation predictions and feasibility configurations provided to the UE in advance. The UE does not necessarily select the first possible handover target.

[0258] Next, we will describe examples of information that may be provided in 8008 signaling.

[0259] This signaling may provide the serving access node with the results of the 8007 evaluation. For example, the signaling may provide the serving access node with indications of time instances in which various measured cells are predicted to be greater than a threshold amount within a window, time instances in which they are predicted to be less than a threshold amount within a window, and / or time instances in which various cells are stronger than other cells in the group of cells being evaluated. As another example, the signaling may also include an indication of which cell is the strongest (including in which time instance).

[0260] As time elapses and window predictions are updated, the target handover time and target cell may change. Therefore, this 8008 signaling may provide updates to previously signaled indicators (for example, if 8005 through 8010 are repeated in a loop). If updates are provided, the UE may decide to omit signaling some of the changes if it determines that those changes are not significant. For example, UE801 may decide that a change is not significant if the change in target time is less than a predetermined amount (for example, less than eps2, where eps2 may be 2*eps, and eps may be half the duration of the reference signal interval).

[0261] The following illustrates how currently defined measurement information elements may be supplemented to report such results; however, this is merely an example, and it should be understood that measurements may be reported using mechanisms different from those provided below.

[0262] In this example, the NR MeasResults information element is extended with a new entry that holds the results of the feasibility configuration. For example, the results may correspond to predicted A3 events in future windows based on the selection of a virtual serving cell.

[0263] The information element MeasResults covers measurement results for in-frequency, inter-frequency, and inter-RAT mobility, as well as measurement results for NR sidelink communication. Newly added fields to this information are shown below in bold. JPEG2026509757000003.jpg202170

[0264] During 8009, the serving access node 802 performs its own evaluation of the information provided during 8008.

[0265] During 8010, the UE and serving access node 802 perform termination of the prediction loop and condition evaluation. For example, if the UE moves out of the cell edge area, it may stop because it no longer needs to run the prediction loop. In other words, during 8010, the UE and serving access node decide whether the UE can stop its signal prediction evaluation.

[0266] During 8011, the serving access node 802 signals to the target access node 803. This signaling allows the target access node 803 to prepare for a potential handover. For example, the network may use reports to prepare the target at the appropriate time on the network.

[0267] In one embodiment, the UE may deliver information to the serving access node that indicates a basic set of events (for example, when the relative cell strengths of different cells are swapped). This information may provide the network with maximum flexibility to determine how and when the UE triggers a handover.

[0268] If the UE delivers information in its report about all potential handover targets within the prediction window, the Serving Access node may select a target cell from among those potential handover targets. This may be done, for example, by determining which handover will result in the minimum interruption time for the UE. The Serving Network node selects one of these potential handover targets as the final handover target. The Serving Access node may signal the UE with an indication of the final handover target in order for the UE to perform the handover to the final handover target.

[0269] If the UE delivers information in its report about a limited number of potential handover targets within a forecast window (for example, one or two potential handover targets), the serving network node may obtain further information to use when selecting which of these potential handover targets to choose. For example, the serving access node may obtain information about the current and / or forecast load being handled by each of these potential handover targets. The serving network node may use this additional information to select one of these potential handover targets as the final handover target. The serving access node may signal the UE an indication of the final handover target in order for the UE to perform the handover to the final handover target.

[0270] As the prediction window loops, the behavior may revert to 8005. This prediction loop can be thought of as predicting future RSRP (or RSRQ) windows and continuously evaluating feasibility conditions over time.

[0271] Continuous evaluation may be started and stopped by the serving access node 802 (for example, started during 8004 and stopped when the UE moves away from the cell edge (not shown)). The serving access node 802 may start a prediction loop based on the recognition that the UE is approaching the cell edge. The serving access node may recognize that the UE is approaching the cell edge based on the reception of periodic or triggered adjacent measurements or timing advance (TA) measurements from the UE, or from the UE's location known by the network. The serving access node may configure a trigger corresponding to the UE, which then indicates to the network as it begins prediction. Similarly, the network may pause the prediction loop. The network may configure the UE to run the prediction loop whenever it receives a new measurement.

[0272] Next, the method executes either 8012 or 8013.

[0273] 8012 relates to network-initiated handover where the serving access node signals an indication of handover of UE801 to target access node 803.

[0274] This may be executed using baseline handover techniques (e.g., signaling at the radio resource control (RRC) level).

[0275] This may alternatively or additionally be executed in the context of LTM, where the UE distributes L1 measurement values to the serving access node, and the serving access node issues a handover command using media access control control element (MAC CE) in response to these measurements.

[0276] 8013 relates to UE-initiated handover from serving access node 802 to target access node 803. This UE-initiated handover may be, for example, a conditional handover preconfigured in the UE by the serving access node. Since serving access node 802 knows the target handover time (range), if serving access node 802 does not agree with the detection result indicated by the UE (reported to serving access node 802 during 8008), the serving access node may have previously sent a "prohibit" message or a handover command to the UE.

[0277] Consider applying the above mechanism to the examples of FIGS. 10 and 6 below.

[0278] Some of the important details of FIG. 10 in this example are as follows.

[0279] The window is predicted to be between time instances A and B. At point C, the serving cell no longer meets the feasibility conditions. Starting from C, the second target cell 1002 has the longest connectivity until the end of the prediction window B and is selected as the target cell for the handover using the selected handover target time D.

[0280] In the example in Figure 6, an exemplary simulation in a serving cell is shown, where gaps in the trace indicate where handovers occurred and measurements could not be collected. In Figure 6, two handovers occurred within 400 milliseconds. The first handover could have been avoided. In this simulation scenario, the UE was moving at a speed of 120 km / h and the carrier frequency was 30 GHz. Handovers were initiated when the adjacent beam was more than 3 dB better offset than the serving beam.

[0281] The example in Figure 6 above (handover to the second target cell at time D) is evaluated by checking the conditions at all time steps. It is assumed that A = 100 milliseconds and B = 600 milliseconds. It is assumed that point C, where service becomes unavailable (assuming an RSRP threshold of -80 dB), occurs at 320 milliseconds. Subsequently, the cell that has survived the longest between C and B becomes the second target cell. In other words, there is no need to hand over to the first target cell 1002. Time D (handover from the serving cell to the second target cell) can occur between 240 milliseconds and 320 milliseconds.

[0282] As mentioned above, the evaluation of feasibility conditions by the UE may vary from implementation to implementation. However, generally, the UE may be configured to predict a window of RSRP (or a similar metric for signal strength and / or quality) and run an algorithm to evaluate the expected state of signals from different cells within that window. The serving network node is primarily involved in the parameterization of feasibility conditions and the results of the evaluation. In principle, it is possible for the UE to use its own algorithm to derive the target cell and time.

[0283] Furthermore, in the example above, the network instructed the UE to perform a cell switch. However, it should be understood that the techniques described herein can be applied equally to network-initiated mobility operations and UE-initiated mobility operations.

[0284] Figures 11 and 12 illustrate operations that can be performed by the apparatus described herein. These operations reflect the features of the example above. Therefore, the following features may coincide with the features of the example above, and therefore may be combined with the above features (in some examples).

[0285] Figure 11 shows the operations that can be performed by the user's device.

[0286] During 1101, the user equipment receives from the network (for example, from an access network node such as a serving network node) an indication for a first time period and an indication for at least one metric predicted within the first time period for at least a serving cell and a plurality of target cells of the network. The predicted at least one metric may be at least one metric for each beam transmitted by the serving cell and the plurality of target cells. Each beam may be the respective reference signal for the serving cell and the plurality of target cells.

[0287] During 1102, the user device receives an indication from the network of a method for identifying potential handover opportunities between a serving cell and at least one of a plurality of target cells within a first time period, using at least one metric, wherein each potential handover opportunity comprises a combination of the target cell's identity and a time instance for performing the handover.

[0288] During 1103, the user device identifies a first set of potential handover opportunities between a serving cell and at least one of several target cells within a first time period, using at least one metric, starting from a first time period. The first set may be equal to 1 (e.g., having a single potential handover opportunity). The first set may be greater than 1 (e.g., having multiple potential handover opportunities).

[0289] During 1104, the user device signals to the network at least one indication of the first set of potential handover opportunities.

[0290] The step of signaling an indication of at least one of the first set of potential handover opportunities to the network may include the steps of signaling an indication of the first set of multiple potential handover opportunities to a serving cell, receiving an indication of a single potential handover opportunity from the first set of multiple potential handover opportunities from the serving cell, and performing a handover to a target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity.

[0291] The identification step may include, for each target cell identified by the plurality of handover opportunities, predicting the value of at least one metric in different time instances within the first time period in order to form the respective predicted metric.

[0292] The indications for the first set of multiple potential handover opportunities signaled to a serving cell may include, for each target cell identified by the first set of multiple potential handover opportunities, at least one of the following: an indication of a time instance in the window when the predicted metric of that target cell is greater than a threshold; an indication of a time instance in the window when the predicted metric of that target cell is less than a threshold; an indication of a time instance in the window when the predicted metric of that target cell is greater by an offset than the same metric predicted for another target cell; an indication of a time instance in the window when the predicted metric of that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of a time instance in the window when the predicted metric of that target cell is less by an offset than the same metric predicted for another target cell; or an indication of a time instance in the window when the predicted metric of that target cell is less by an offset than the same metric predicted for a serving cell.

[0293] The step of signaling an indication of at least one of the first set of potential handover opportunities to the network may comprise the steps of signaling an indication of a single potential handover opportunity to a serving cell, and performing a handover to a target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity.

[0294] The identification step may include, for each target cell identified by a first set of potential handover opportunities, predicting the value of at least one metric in different time instances within the first time period to form a predicted metric for each of them, and selecting a single potential handover opportunity by selecting a single potential handover opportunity using the predicted metric.

[0295] At least one of the predicted values ​​for a target cell may include at least one of the following: an indication of the time instance within the window when the predicted metric for that target cell is greater than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is less than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset amount than the same metric predicted for another target cell; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset amount than the same metric predicted for a serving cell; an indication of the time instance within the window when the predicted metric for that target cell is less by an offset amount than the same metric predicted for another target cell; or an indication of the time instance within the window when the predicted metric for that target cell is less by an offset amount than the same metric predicted for a serving cell. The offset amount may depend on the state of the wireless network, as the actual handover margin is important. The offset may be zero. The offset may be greater than zero.

[0296] User equipment may refrain from performing a handover in one of the first handover opportunities in a first set, and may perform a handover to a selected target cell in one of the second handover opportunities, provided that the second handover opportunity occurs after the first handover opportunity. This restraint and performance may be performed with respect to either a network initiation handover or a user equipment handover.

[0297] The user equipment may identify a second set of potential handover opportunities between the serving cell and at least one of a plurality of target cells within a first time period, using at least one metric for the first time period starting from a second time, where the second time is after the first time, and signal at least one indication of the second set of potential handover opportunities to the serving cell. For example, the user equipment may loop through any of the above procedures.

[0298] The at least one metric may comprise reference signal received power and / or reference signal received quality.

[0299] FIG. 12 shows operations that may be performed by an apparatus for a serving access node that provides a serving cell to a user equipment. The user equipment may be as described above in relation to FIG. 12.

[0300] Between 1201, the serving access node signals to the user equipment an indication of the first time period and an indication of at least one metric predicted within the first time period for at least the serving cell and a plurality of target cells.

[0301] Between 1202, the serving access node signals to the user equipment an indication of a method for identifying potential handover opportunities between the serving cell and at least one of a plurality of target cells within the first time period using at least one metric, where the potential handover opportunities comprise respective combinations of an identity of a target cell and a time instance for performing the handover.

[0302] During 1203, the serving access node receives an indication from the user device using at least one metric for at least one of a first set of potential handover opportunities to hand over the user device from the serving cell to at least one of multiple serving cells within a first time period. The first set may be equal to 1 (for example, having a single potential handover opportunity). The first set may be greater than 1 (for example, having multiple potential handover opportunities).

[0303] The serving access node may include an access network node (e.g., a gNB).

[0304] The step of receiving an indication of at least one of the first set of potential handover opportunities may include the steps of receiving an indication of a single potential handover opportunity and causing a handover to the target cell identified by the single potential handover opportunity to be performed in the time instance indicated by the single potential handover opportunity. The step of causing a handover may include the serving access node sending a handover command to the user device to instruct the user device to perform a handover to the target cell in the time instance indicated by the single potential handover opportunity. The step of causing a handover may include sending a conditional handover configuration to the user device to prepare the user device for a conditional handover opportunity to the target cell (for example, if the user device determines that a set of conditions associated with the conditional handover has been met, the UE initiates a handover to the target cell).

[0305] The step of receiving an indication of at least one of the first set of potential handover opportunities may include receiving indications of the first set of multiple potential handover opportunities from the user device; selecting a single potential handover opportunity from the potential handover opportunities by determining that a target cell identified by a single potential handover opportunity can also provide coverage to the user device during a time instance associated with another of the first set of potential handover opportunities; and signaling the user device an indication of a single potential handover opportunity from the first set of multiple potential handover opportunities.

[0306] The step of receiving an indication of at least one of a first set of potential handover opportunities may include receiving values ​​of at least one metric at different time instances within the first time period to form a predicted metric for each target cell identified by the first set of potential handover opportunities, and the step of selecting a single potential handover opportunity may include selecting a single potential handover opportunity using the predicted metric.

[0307] At least one of the predicted values ​​for a target cell may include at least one of the following: an indication of the time instance within the window when the predicted metric for that target cell is greater than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is less than a threshold; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for another target cell; an indication of the time instance within the window when the predicted metric for that target cell is greater by an offset than the same metric predicted for a serving cell; an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for another target cell; or an indication of the time instance within the window when the predicted metric for that target cell is less by an offset than the same metric predicted for a serving cell.

[0308] A serving network node may hand over a user device to a target cell identified by a single potential handover opportunity in a time instance indicated by a single potential handover opportunity.

[0309] A serving network node may allow a user device to perform a handover by refraining from performing a handover in one of the first of a first set of handover opportunities, and by performing a handover to a selected target cell in one of a second of the handover opportunities, wherein the second of the handover opportunities occurs after the first of the handover opportunities.

[0310] A serving network node may receive an indication from a user device of a second set of potential handover opportunities between a serving cell and at least one of a plurality of target cells within a first time period, wherein the second set of potential handover opportunities relates to a set of predictions made using metrics for a first time period beginning at a second time, and the second time is later than the first time, and may hand over the user device to a target cell identified by at least one of the second set of potential handover opportunities in a time instance indicated by one of the second set of potential handover opportunities.

[0311] At least one metric may include reference signal received power and / or reference signal received quality.

[0312] The techniques described herein can avoid unnecessary handovers. This helps minimize the disruption caused by signaling between different entities when new events are defined and legacy events are not configured, as well as the tasks associated with handovers, signaling between network nodes, and node preparation.

[0313] The foregoing explanation, as a non-limiting example, has provided a complete and useful description of several examples. However, by reading the foregoing explanation in conjunction with the attached drawings and claims, various modifications and adaptations will become apparent to those skilled in the art in the relevant field. However, all such modifications and similar modifications of the teachings will still be included within the scope of the claims.

[0314] The above examples illustrate various access architectures to which the described techniques may be applied, using radio access architectures based on Long-Term Evolution Advanced (LTE-A) or New Radio (NR, 5G). However, the examples are not limited to such architectures. These examples can also be applied to other types of communication networks with appropriate means by appropriately adjusting parameters and procedures. Examples of other options for suitable systems include Universal Mobile Telecommunications System (UMTS) radio access networks (UTRAN), wireless local area networks (WLAN or Wi-Fi), global interoperability microwave access (WiMAX), Bluetooth®, Personal Communication Services (PCS), ZigBee®, wideband code division multiple access (WCDMA), systems using ultra-wideband (UWB) technology, sensor networks, mobile ad hoc networks (MANET), and Internet Protocol Multimedia Subsystem (IMS), or combinations thereof.

[0315] As described herein, various embodiments are described in the detailed description of the examples and in the claims. Generally, some embodiments may be implemented in hardware or dedicated circuitry, software code, logic, or any combination thereof. For example, some embodiments may be implemented in hardware, while others may be implemented in firmware or software code that can be executed by a controller, microprocessor, or other computing device, but the examples are not limited to these. Various embodiments may be illustrated and described as block diagrams, flowcharts, or using any other graphic representation, but it will be understood that these blocks, apparatus, systems, techniques, or methods described herein may be implemented in hardware, software code, firmware code, dedicated circuitry or logic, general-purpose hardware or controllers, or other computing devices, or a combination thereof, as non-limiting examples.

[0316] These examples may be implemented by computer software code stored in memory and executable by at least one data processor of the entities involved, or by hardware, or by a combination of software code and hardware.

[0317] The memories referred to herein are of any type suitable for the local technical environment and can be implemented using any suitable data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory.

[0318] The (data) processors referred to herein may be of any type suitable for the local technical environment and may include, in non-limiting examples, one or more of the following: general-purpose computers, dedicated computers, microprocessors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), FPGAs, gate-level circuits, and processors based on multicore processor architectures.

[0319] Furthermore, it should be noted that in this regard, for example, Figures 11 and / or 12, and / or other procedures described above, may represent the operation of a computer program deployed by at least one processor provided in the device (the computer program comprises instructions for causing the device to perform at least one action, and the instructions are represented as software code stored in at least one memory), or interconnected logic circuits, blocks and functions, or combinations of the operation of a computer program deployed by at least one processor provided in the device with logic circuits, blocks and functions. The software code may be stored in memory such as physical media such as memory chips, memory blocks implemented within the processor, magnetic media (such as hard disks or floppy disks), and optical media (such as DVDs and their data variants, CDs, etc.).

[0320] Memory can be of any type suitable for the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The data processor can be of any type suitable for the local technical environment and may comprise, in non-limiting examples, one or more of the following: general-purpose computers, dedicated computers, microprocessors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), gate-level circuits, and processors based on multi-core processor architectures.

[0321] Additionally or alternatively, some examples may be implemented using circuits. The circuits may be configured to perform one or more of the functions and / or method steps described above. The circuits may be located within base stations and / or communication devices and / or core network entities.

[0322] As used in this application, the term “circuit” may refer to one or more, or all of the following: (a) Implementation of circuits using only hardware (such as implementation of only analog circuits and / or only digital circuits), (b) The following combinations of hardware and software circuits: (i) combinations of analog hardware circuits and / or digital hardware circuits and software code / firmware code, (ii) Any part of a hardware processor having software code (including a digital signal processor), software code, and memory that works in conjunction to cause a device such as a communication device or base station to perform the various functions described above, (c) Hardware circuits and / or processors, such as a microprocessor or part of a microprocessor, that require software code (e.g., firmware) for operation, but where the software code may not be present if it is not required for operation.

[0323] This definition of circuit applies to all use of this term in this application, including in all claims. Further examples include, as used in this application, the term circuit also covers the implementation of a hardware circuit or processor (or more processors), or a part of a hardware circuit or processor and the software and / or firmware code associated with it (or them). The term circuit also covers, for example, integrated devices.

[0324] The implementation of this disclosure may be practiced in various components, such as integrated circuit modules. Integrated circuit design is generally a highly automated process. Complex and powerful software tools are available to translate logic-level designs into semiconductor circuit designs that can be etched onto semiconductor substrates.

[0325] As used herein, “at least one of the following: <list of two or more elements>” and “at least one of the <list of two or more elements>” and similar phrases in which lists of two or more elements are joined by “and” or “or” mean at least one of the elements, or at least two or more of the elements, or at least all of the elements.

[0326] As used herein, the term “non-transient” refers to the limitations of the media itself (i.e., tangible, not signal-based) rather than limitations on the persistence of data storage (e.g., RAM and ROM).

[0327] The scope of protection required for various examples of disclosure is defined by the independent claims. If any examples and features described herein do not fall within the scope of the independent claims, they shall be construed as examples that are helpful in understanding this disclosure.

[0328] The foregoing description, as a non-limiting example, has provided a complete and useful description of exemplary implementations of the present disclosure. However, by reading the foregoing description in conjunction with the accompanying drawings and claims, various modifications and adaptations will become apparent to those skilled in the art. However, all such modifications and similar modifications of the teachings of the present disclosure will still fall within the scope of the invention as defined in the accompanying claims. In fact, there are further implementations that involve combinations of one or more of the other implementations described herein.

Claims

1. A device for user equipment, Means for receiving from a network, for at least the serving cells and a plurality of target cells of the network, an indication for a first time period and an indication for at least one metric predicted within the first time period, Means for receiving an indication from the network of a method for identifying a potential handover opportunity between the serving cell and at least one of the plurality of target cells within a first time period using the at least one metric, wherein the potential handover opportunity comprises a combination of the identity of the target cell and a time instance for performing the handover. Means for identifying a first set of potential handover opportunities between the serving cell and at least one of the plurality of target cells within the first time period, using the at least one metric, Means for signaling to the network at least one indication from the first set of potential handover opportunities A device equipped with the following features.

2. The means for signaling at least one of the indications from the first set of potential handover opportunities to the network, Means for signaling the serving cell an indication of the first set of multiple potential handover opportunities, Means for receiving an indication from the serving cell of a single potential handover opportunity from a first set of multiple potential handover opportunities, Means for performing the handover to the target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity The apparatus according to claim 1, comprising:

3. The apparatus according to claim 2, wherein the means for identification comprises means for predicting the value of at least one metric in different time instances within the first time period in order to form a predicted metric for each target cell identified by the plurality of handover opportunities.

4. The indication of the first set of multiple potential handover opportunities signaled to the serving cell is, for each target cell identified by the first set of multiple potential handover opportunities, If the predicted metric for the target cell is greater than the threshold, the indication of the time instance within the window, Indication of the time instance within the window when the predicted metric for the target cell is smaller than the threshold, Indication of a time instance within the window when the predicted metric for that target cell is greater by an offset amount than the same metric predicted for another target cell, Indication of a time instance within the window when the predicted metric for the target cell is greater by the offset amount than the same metric predicted for the serving cell, Indication of a time instance within the window when the predicted metric for that target cell is smaller by the offset amount than the same metric predicted for another target cell, or Indication of time instances within the window when the predicted metric for the target cell is smaller by the offset amount than the same metric predicted for the serving cell. The apparatus according to claim 3, comprising at least one of the following.

5. The means for signaling to the network at least one of the indications of the first set of potential handover opportunities, Means for signaling the serving cell an indication of a single potential handover opportunity, Means for performing the handover to the target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity The apparatus according to claim 1, comprising:

6. The means for identification includes, for each target cell identified by the first set of potential handover opportunities, means for predicting the value of at least one metric in different time instances within the first time period in order to form a respective predicted metric, By selecting the single potential handover opportunity using the predicted metric, the means for selecting the single potential handover opportunity and The apparatus according to claim 5, comprising:

7. At least one of the predicted values ​​for the target cell is If the predicted metric for the target cell is greater than the threshold, the indication of the time instance within the window, Indication of the time instance within the window when the predicted metric for the target cell is smaller than the threshold, Indication of a time instance within the window when the predicted metric for that target cell is greater by an offset amount than the same metric predicted for another target cell, Indication of a time instance within the window when the predicted metric for the target cell is greater by the offset amount than the same metric predicted for the serving cell, Indication of a time instance within the window when the predicted metric for that target cell is smaller by the offset amount than the same metric predicted for another target cell, or Indication of time instances within the window when the predicted metric for the target cell is smaller by the offset amount than the same metric predicted for the serving cell. The apparatus according to claim 6, comprising at least one of the following.

8. A means for restraining the execution of a handover in one of the first handover opportunities of the first set, A means for performing a handover to one of the selected target cells in a second of the handover opportunities, wherein the second of the handover opportunities occurs after the first of the handover opportunities. The apparatus according to any one of claims 1 to 7, comprising:

9. Means for identifying a second set of potential handover opportunities between the serving cell and at least one of the plurality of target cells within a first time period beginning at a second time, using at least one metric, wherein the second time is later than the first time. Means for signaling the serving cell to at least one indication from the second set of potential handover opportunities The apparatus according to any one of claims 1 to 8, comprising:

10. A device for a serving access node that provides serving cells to user equipment, Means for signaling to the user device, for at least the serving cell and a plurality of target cells, an indication for a first time period and an indication for at least one metric predicted within the first time period, Means for signaling to the user device an indication of a method for identifying a potential handover opportunity between the serving cell and at least one of the plurality of target cells within a first time period, wherein the potential handover opportunity comprises a combination of the identity of the target cell and a time instance for performing the handover. Means for receiving an indication from the user device, using the at least one metric, of at least one of a first set of potential handover opportunities for handing over the user device from the serving cell to at least one of the plurality of serving cells within the first time period; A device equipped with the following features.

11. The means for receiving at least one of the first set of potential handover opportunities is A means of receiving indication of a single potential handover opportunity, Means for causing the handover to the target cell identified by the single potential handover opportunity to be performed in the time instance indicated by the single potential handover opportunity. The apparatus according to claim 10, comprising:

12. The means for receiving at least one of the first set of potential handover opportunities is Means for receiving indications of the first set of multiple potential handover opportunities from the user device, Means for selecting a single potential handover opportunity from the potential handover opportunities, by determining that the target cell identified by the single potential handover opportunity can also provide coverage to the user equipment during a time instance associated with another of the first set of potential handover opportunities, Means for signaling to the user device an indication of the single potential handover opportunity from the first set of the plurality of potential handover opportunities. The apparatus according to claim 10, comprising:

13. The means for receiving an indication of at least one of a first set of potential handover opportunities comprises, for each target cell identified by the first set of potential handover opportunities, means for receiving the value of the at least one metric in different time instances within the first time period in order to form a predicted metric for each of them. The apparatus according to claim 12, wherein the means for selecting the single potential handover opportunity comprises means for selecting the single potential handover opportunity using the predicted metric.

14. At least one of the predicted values ​​for the target cell is If the predicted metric for the target cell is greater than the threshold, the indication of the time instance within the window, Indication of the time instance within the window when the predicted metric for the target cell is smaller than the threshold, Indication of a time instance within the window when the predicted metric for that target cell is greater by an offset amount than the same metric predicted for another target cell, Indication of a time instance within the window when the predicted metric for the target cell is greater by the offset amount than the same metric predicted for the serving cell, Indication of a time instance within the window when the predicted metric for that target cell is smaller by the offset amount than the same metric predicted for another target cell, or Indication of time instances within the window when the predicted metric for the target cell is smaller by the offset amount than the same metric predicted for the serving cell. The apparatus according to claim 13, comprising at least one of the following.

15. The apparatus according to any one of claims 11 to 14, comprising means for handing over the user device to the target cell identified by the single potential handover opportunity in the time instance indicated by the single potential handover opportunity.

16. To refrain from performing a handover in one of the first handover opportunities of the first set, The apparatus according to any one of claims 10 to 14, comprising means for causing the user device to perform a handover by performing a handover to a selected one of the plurality of target cells in a second of the handover opportunities, wherein the second of the handover opportunities occurs after the first of the handover opportunities.

17. Means for receiving indications from the user device of a second set of potential handover opportunities between the serving cell and at least one of the plurality of target cells within the first time period, wherein the second set of potential handover opportunities relates to a set of predictions made using the metric for the first time period starting from a second time, and the second time is later than the first time. Means for handing over the user device to the target cell identified by at least one of the second set of potential handover opportunities in the time instance indicated by at least one of the second set of potential handover opportunities The apparatus according to any one of claims 10 to 16, comprising:

18. The apparatus according to any one of claims 10 to 17, wherein the at least one metric comprises reference signal received power and / or reference signal received quality.

19. The steps include receiving from the network, for at least the serving cells and a plurality of target cells of the network, an indication for a first time period and an indication for at least one metric predicted within the first time period; Steps include receiving an indication from the network of a method for identifying potential handover opportunities between the serving cell and at least one of the plurality of target cells within a first time period, using the at least one metric, wherein the potential handover opportunity comprises a combination of the identity of the target cell and a time instance for performing the handover. The steps include: identifying a first set of potential handover opportunities between the serving cell and at least one of the plurality of target cells within the first time period, using the at least one metric, The steps include signaling the network to at least one indication from the first set of potential handover opportunities and A method for user equipment that includes the following features.

20. A method for a serving access node that provides serving cells to user equipment, The steps include signaling to the user device, for at least the serving cell and a plurality of target cells, an indication for a first time period and an indication for at least one metric predicted within the first time period; A step of signaling the user device an indication of a method for identifying a potential handover opportunity between the serving cell and at least one of the plurality of target cells within a first time period, wherein the potential handover opportunity comprises a combination of the identity of the target cell and a time instance for performing the handover. The steps include: receiving an indication from the user device, using the at least one metric, of at least one of a first set of potential handover opportunities for handing over the user device from the serving cell to at least one of the plurality of serving cells within a first time period; A method that includes [a certain feature].

21. When executed by a device for user equipment, the device will: Receiving from the network, for at least the serving cells and multiple target cells of the network, an indication for a first time period and an indication for at least one metric predicted within the first time period. Receiving an indication from the network of a method for identifying a potential handover opportunity between the serving cell and at least one of the plurality of target cells within a first time period, using the at least one metric, wherein the potential handover opportunity comprises a combination of the target cell's identity and a time instance for performing the handover. In the first time period beginning from the first time, the at least one metric is used to identify a first set of potential handover opportunities between the serving cell and at least one of the plurality of target cells within the first time period, Signaling to the network at least one indication from the first set of potential handover opportunities A computer program that contains instructions to execute.

22. When executed by a device for a serving access node that provides serving cells to user equipment, the device: Signaling to the user device, for at least the serving cell and a plurality of target cells, an indication for a first time period and an indication for at least one metric predicted within the first time period; Signaling to the user device an indication of a method for identifying a potential handover opportunity between the serving cell and at least one of the plurality of target cells within a first time period, wherein the potential handover opportunity comprises a combination of the identity of the target cell and a time instance for performing the handover. The user device receives, using the at least one metric, an indication of at least one of a first set of potential handover opportunities for handing over the user device from the serving cell to at least one of the plurality of serving cells within the first time period. A computer program that contains instructions to be executed.

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