Apparatuses and methods for managing subsequent conditional pscell addition conditions

Abstract

Example embodiments enable managing subsequent conditional PScell additions upon a secondary cell group release. A master node may be configured to send, to a user node, at least one execution condition for a conditional primary secondary cell, PScell, addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change, SCPAC, condition for CPA execution to be performed after a secondary cell group, SCG, release, and wherein the at least one execution condition for CPA is configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change, CPC. Apparatuses, methods, and computer programs are disclosed.

Description

APPARATUSES AND METHODS FOR MANAGING SUBSEQUENT CONDITIONALPSCELL ADDITION CONDITIONSTECHNICAL FIELD

[0001] The present application generally relates to information technology . In particular, some example embodiments of the present application relate to management of conditions for subsequent conditional PScell additions / changes upon or after a secondary cell group release .BACKGROUND

[0002] MR-DC (multi radio dual connectivity) refers to a range of di f ferent dual connectivity configuration options , which may be associated with 5G . MR-DC with selective activation of cell groups aims at enabl ing subsequent CPC ( conditional PScell change ) and CPA ( conditional PScell addition) after SCG ( secondary cell group ) change , without reconfiguration and re-initiali zation on the CPC / CPA preparation from the network .SUMMARY

[0003] This summary is provided to introduce a selection of concepts in a simpli fied form that are further described below in the detailed description . This summary is not intended to identi fy key features or essential features of the claimed subj ect matter, nor is it intended to be used to limit the scope of the claimed subj ect matter .

[0004] Example embodiments may enable managing subsequent conditional PScell addition / change condition configuration such that a CPC condition is updated to a CPA condition for CPA execution upon or after a SCG release , wherein the CPC condition associated with secondary node measurement configurations may be at least partially updated or the CPCcondition may be updated to a condition associated with master node measurement configurations . This may be achieved by the features of the independent claims . Further implementation forms are provided in the dependent claims , the description, and the drawings .

[0005] According to a first aspect , a master node comprises at least one processor ; and at least one memory including instructions which, when executed by the at least one processor, cause the master node at least to send, to a user node , at least one execution condition for a conditional primary secondary cel l , PScell , addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change , SCPAC, condition for execution of CPA to be performed after a secondary cell group, SCG, release , and wherein the at least one execution condition for CPA is configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change , CPC .

[0006] According to an implementation form of the first aspect , the at least one execution condition for CPA comprises at least one A4 event condition mapped to a master cell group, MCG, configuration, wherein the at least one A4 event condition is defined for candidate SCPAC configurations .

[0007] According to an implementation form of the first aspect , the at least one execution condition comprises one A4 event condition common for all candidate SCPAC configurations .

[0008] According to an implementation form of the first aspect , the at least one execution condition comprises A4 event conditions speci fic for each candidate SCPAC configuration .

[0009] According to an implementation form of the first aspect , the at least one execution condition comprises instructions to maintain measurement configurations associated with the released SCG and SCPAC condition evaluation wherein the instructions instruct the user node to continue , after the SCG release , SCPAC condition evaluation based on at least one of A3 event condition or A5 event condition of the CPC with measurement configurations associated with the released SCG .

[0010] According to an implementation form of the first aspect , the at least one memory comprises instructions which, when executed by the at least one proces sor, cause the master node to send an indication to deactivate the at least one execution condition; detect a need for a SCG release ; and send a reconfiguration message for the SCG release comprising an indication to the user node to activate the at least one execution condition .

[0011] According to an implementation form of the first aspect , the at least one execution condition is sent in a radio resource control , RRC, reconfiguration message for the SCG release .

[0012] According to an implementation form of the first aspect , the at least one execution condition is sent in a radio resource control , RRC , reconfiguration message including at least one of an initial conditional PScell change , CPC, condition configuration or a subsequent CPC condition configuration .

[0013] According to an implementation form of the first aspect , the at least one memory further comprises instructions which, when executed by the at least one processor, cause the master node to send instructions to the user node to suspend evaluation of the at least one execution condition for the released SCG .

[0014] According to an implementation form of the first aspect , the instructions sent to the user node comprise instructions to suspend the evaluation of the at least one execution condition for the released SCG for a certain period of time from the SCG release .

[0015] According to an implementation form of the first aspect , the instructions sent to the user node comprise instructions to suspend the evaluation of the at least one execution condition for the released SCG until the user node executes at least one conditional PCell addition .

[0016] According to a second aspect , a user node comprises at least one processor ; and at least one memory including instructions which, when executed by the at least one processor, cause the user node at least to receive , from a master node , at least one execution condition for a conditional primary secondary cel l , PScell , addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change , SCPAC, condition for execution of CPA to be performed after a secondary cell group, SCG, release , wherein the at least one execution condition for CPA is configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change , CPC .

[0017] According to an implementation form of the second aspect , the at least one execution condition for CPA comprise at least one A4 event condition mapped to a master cel l group, MCG, configuration, wherein the at least one A4 event condition is defined for candidate SCPAC configurations .

[0018] According to an implementation form of the second aspect , the at least one execution condition for CPA comprises one A4 event condition common for all candidate SCPAC configurations .

[0019] According to an implementation form of the second aspect , the at least one execution condition for CPA comprises A4 event conditions specific for each candidate SCPAC configuration .

[0020] According to an implementation form of the second aspect , the at least one execution condition for CPA comprises instructions to maintain measurement configurations associated with the released SCG and SCPAC condition evaluation wherein the instructions instruct the user node to continue , after the SCG release , SCPAC condition evaluation based on the at least one of A3 event condition or A5 event condition of the CPC with measurement configurations associated with the released SCG .

[0021] According to an implementation form of the second aspect , the at least one execution condition for CPA is received in a radio resource control , RRC, reconfiguration message including at least one of an initial CPC condition configuration or a subsequent CPC condition configuration .

[0022] According to an implementation form of the second aspect , the at least one execution condition for CPA is received in a RRC reconfiguration message for the SCG release .

[0023] According to an implementation form of the second aspect , the at least one memory further comprises instructions which, when executed by the at least one processor, cause the user node to receive instructions from the master node to suspend evaluation of the at least one execution condition for CPA for the released SCG; and suspend the evaluation of the at least one execution condition for CPA for the released SCG according to the instructions .

[0024] According to an implementation form of the second aspect , the instructions received from the master node comprise instructions to suspend the evaluation of the atleast one execution condition for CPA for the released SCG for a certain period of time from the SCG release .

[0025] According to an implementation form of the second aspect , the instructions received from the master node comprise instructions to suspend the evaluation of the at least one execution condition for CPA for the released SCG until the user node executes at least one conditional PCell addition .

[0026] According to an implementation form of the second aspect , the at least one memory comprises instructions which, when executed by the at least one processor, cause the user node to receive , from the master node , a reconfiguration message for SCG release ; perform the SCG release , comprising releasing SCG configuration, releasing measurement configuration of at least one of an initial CPC condition or a subsequent CPC condition, releasing at least one of the CPC condition or the subsequent CPC condition; and cause the user node to : evaluate the SCPAC condition based on the at least one execution condition for CPA; and after the SCG release , execute CPA based on the evaluating .

[0027] According to an implementation form of the second aspect , the at least one memory comprises instructions which, when executed by the at least one processor, cause the user node to receive , from the master node , the at least one execution condition for CPA with an indication to deactivate the at least one execution condition for CPA; store the at least one execution condition in a deactivated state ; and receive , from the master node , the reconfiguration message for the SCG release with an indication to activate the at least one execution condition for CPA.

[0028] According to an implementation form of the second aspect , the at least one memory comprises instruction which, when executed by the at least one processor, cause the user node to receive , from the master node , a reconfigurationmessage for SCG release before an initial conditional PScell change has been executed; perform the SCG release , comprising releasing SCG configuration, maintaining measurement configurations of initial CPC conditions and maintaining initial CPC conditions ; and cause the user node to : update the initial CPC conditions for CPA, wherein the initial CPC conditions are evaluated for candidate SCPAC configurations with released PScell measurements as serving PScell measurements ; and upon or after the SCG release , perform evaluation for the conditional PScell addition execution based on the update .

[0029] According to an implementation form of the second aspect , the at least one memory comprises instruction which, when executed by the at least one processor, cause the user node to receive , from the master node , a reconfiguration message for SCG release after an initial conditional PScell change has been executed; perform the SCG release , comprising maintaining SCG configuration, maintaining measurement configurations of subsequent conditional PScell change , CPC , conditions and maintaining subsequent CPC conditions ; and cause the user node to : update the subsequent CPC conditions for CPA, wherein the subsequent CPC conditions are evaluated for candidate SCPAC configurations with released PScell measurements as serving PScell measurements ; and upon or after the SCG release , perform evaluation for the conditional PScell addition execution based on the update .

[0030] According to a third aspect , a method to be carried out by a master node is provided . TH emethod comprises sending, to a user node , at least one execution condition for a conditional primary secondary cell , PScell , addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change , SCPAC, condition for execution of CPA to be performed after a secondary cell group, SCG, release , and wherein the at leastone execution condition for CPA is configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change , CPC .

[0031] According to an implementation form of the third aspect , the at least one execution condition for CPA comprises at least one A4 event condition mapped to a master cell group, MCG, configuration, wherein the at least one A4 event condition is defined for candidate SCPAC configurations .

[0032] According to an implementation form of the third aspect , the at least one execution condition comprises one A4 event condition common for all candidate SCPAC configurations .

[0033] According to an implementation form of the third aspect , the at least one execution condition comprises A4 event conditions speci fic for each candidate SCPAC configuration .

[0034] According to an implementation form of the third aspect , the at least one execution condition comprises instructions to maintain measurement configurations associated with the released SCG and SCPAC condition evaluation wherein the instructions instruct the user node to continue , after the SCG release , SCPAC condition evaluation based on at least one of A3 event condition or A5 event condition of the CPC with measurement configurations associated with the released SCG .

[0035] According to an implementation form of the third aspect , the method comprises sending an indication to deactivate the at least one execution condition; detecting a need for a SCG release ; and sending a reconfiguration message for the SCG release comprising an indication to the user node to activate the at least one execution condition .

[0036] According to an implementation form of the third aspect , the at least one execution condition is sent in a radio resource control , RRC, reconfiguration message for theSCG release .

[0037] According to an implementation form of the third aspect , the at least one execution condition is sent in a radio resource control , RRC , reconfiguration message including at least one of an initial conditional PScell change , CPC, condition configuration or a subsequent CPC condition configuration .

[0038] According to an implementation form of the third aspect , the method comprises sending instructions to the user node to suspend evaluation of the at least one execution condition for the released SCG .

[0039] According to an implementation form of the third aspect , the instructions sent to the user node comprise instructions to suspend the evaluation of the at least one execution condition for the released SCG for a certain period of time from the SCG release .

[0040] According to an implementation form of the third aspect , the instructions sent to the user node comprise instructions to suspend the evaluation of the at least one execution condition for the released SCG until the user node executes at least one conditional PCell addition .

[0041] According to a fourth aspect , a method to be carried out by a user node is provided . The method comprises receiving, from a master node , at least one execution condition for a conditional primary secondary cell , PScell , addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change , SCPAC, condition for execution of CPA to be performed after a secondary cell group, SCG, release , wherein the at least one execution condition for CPA is configured to replace at least one execution condition configured to the user node forevaluation of the SCPAC condition for a conditional PScell change , CPC .

[0042] According to an implementation form of the fourth aspect , the at least one execution condition for CPA comprise at least one A4 event condition mapped to a master cel l group, MCG, configuration, wherein the at least one A4 event condition is defined for candidate SCPAC configurations .

[0043] According to an implementation form of the fourth aspect , the at least one execution condition for CPA comprises one A4 event condition common for all candidate SCPAC configurations .

[0044] According to an implementation form of the fourth aspect , the at least one execution condition for CPA comprises A4 event conditions specific for each candidate SCPAC configuration .

[0045] According to an implementation form of the fourth aspect , the at least one execution condition for CPA comprises instructions to maintain measurement configurations associated with the released SCG and SCPAC condition evaluation wherein the instructions instruct the user node to continue , after the SCG release , SCPAC condition evaluation based on the at least one of A3 event condition or A5 event condition of the CPC with measurement configurations associated with the released SCG .

[0046] According to an implementation form of the fourth aspect , the at least one execution condition for CPA is received in a radio resource control , RRC, reconfiguration message including at least one of an initial CPC condition configuration or a subsequent CPC condition configuration .

[0047] According to an implementation form of the fourth aspect , the at least one execution condition for CPA is received in a RRC reconfiguration message for the SCG release .

[0048] According to an implementation form of the fourth aspect , the method comprises receiving, from the master node , instructions to suspend evaluation of the at least one execution condition for CPA for the released SCG; and suspending the evaluation of the at least one execution condition for CPA for the released SCG according to the instructions .

[0049] According to an implementation form of the fourth aspect , the instructions received from the master node comprise instructions to suspend the evaluation of the at least one execution condition for CPA for the released SCG for a certain period of time from the SCG release .

[0050] According to an implementation form of the fourth aspect , the instructions received from the master node comprise instructions to suspend the evaluation of the at least one execution condition for CPA for the released SCG until the user node executes at least one conditional PCell addition .

[0051] According to an implementation form of the fourth aspect , the method comprises receiving, from the master node , a reconfiguration message for SCG release ; performing the SCG release , comprising releasing SCG configuration, releasing measurement configuration of at least one of an initial CPC condition or a subsequent CPC condition, releasing at least one of the CPC condition or the subsequent CPC condition and applying the SCPAC condition evaluation based on the at least one execution condition for CPA; and upon or after the SCG release , performing evaluation for the conditional PScell addition execution based on the applied at least one execution condition for CPA for the candidate SCPAC configurations .

[0052] According to an implementation form of the fourth aspect , the method comprises receiving, from the master node , the at least one execution condition for CPA with anindication to deactivate the at least one execution condition for CPA; storing the at least one execution condition in a deactivated state ; and receiving, from the master node , the reconfiguration message for the SCG release with an indication to activate the at least one execution condition for CPA.

[0053] According to an implementation form of the fourth aspect , the method comprises receiving, from the master node , a reconfiguration message for SCG release before an initial conditional PScell change has been executed; performing the SCG release , comprising maintaining SCG configuration, maintaining measurement configurations of initial CPC conditions and maintaining initial CPC conditions ; updating the initial CPC conditions for CPA, wherein the initial CPC conditions are evaluated for candidate SCPAC configurations with released PScell measurements as serving PScell measurements ; and upon or after the SCG release , performing evaluation for the conditional PScell addition execution based on the update .

[0054] According to an implementation form of the fourth aspect , the method comprises receiving, from the master node , a reconfiguration message for SCG release after an initial conditional PScell change has been executed; performing the SCG release , comprising maintaining SCG configuration, maintaining measurement configurations of subsequent conditional PScell change , CPC, conditions and maintaining subsequent CPC conditions ; and updating the subsequent CPC conditions for CPA, wherein the subsequent CPC conditions are evaluated for candidate SCPAC configurations with released PScell measurements as serving PScell measurements ; and upon or after the SCG release , performing evaluation for the conditional PScell addition execution based on the update .

[0055] According to a fi fth aspect , an apparatus comprises at least means for sending, to a user node , at least one execution condition for a conditional primary secondary cell , PScell , addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change , SCPAC, condition evaluation for execution of CPA to be performed after a secondary cell group, SCG, release , and wherein the at least one execution condition for CPA is configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change , CPC . The apparatus may further comprise means for performing any implementation form of the method according to the third aspect .

[0056] According to a sixth aspect , a computer readable medium comprises instructions which, when executed by an apparatus , cause the apparatus to perform any implementation form of the method according to the third aspect .

[0057] According to a seventh aspect , an apparatus comprises at least means for receiving, from a master node , at least one execution condition for a conditional primary secondary cell , PScell , addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change , SCPAC, condition evaluation for execution of CPA to be performed after a secondary cell group, SCG, release , and wherein the at least one execution condition for CPA is configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change , CPC . The apparatus may further comprise means for performing any implementation form of the method according to the fourth aspect .

[0058] According to an eight aspect , a computer readable medium comprises instructions which, when executed by anapparatus cause the apparatus to perform any implementation form of the method according to the fourth aspect .

[0059] Many of the attendant features will be more readily appreciated as they become better understood by reference to the following detai led description considered in connection with the accompanying drawings .DESCRIPTION OF THE DRAWINGS

[0060] The accompanying drawings , which are included to provide a further understanding of the example embodiments and constitute a part of this speci fication, illustrate example embodiments and together with the description help to explain the example embodiments . In the drawings :

[0061] FIG . 1 illustrates an example of a communication system comprising network nodes and at least one client node according to an example embodiment .

[0062] FIG . 2 illustrates an example of an apparatus configured to practice one or more example embodiments ;

[0063] FIG . 3 illustrates an example of a message sequence chart for managing SCPAC condition for CPA execution upon or after SCG release according to an example embodiment ;

[0064] FIG . 4 illustrates an example of a message sequence chart for managing SCPAC condition upon SCG release according to an example embodiment ;

[0065] FIG . 5 illustrates an example of a message sequence chart for managing SCPAC condition with a partial release of a previous condition upon SCG release according to an example embodiment ;

[0066] FIG . 6 illustrates an example of a method for managing SCPAC condition for CPA execution upon or after SCG release by a network node according to an example embodiment ;

[0067] FIG . 7 illustrates an example of a method for managing SCPAC condition for CPA execution upon or after SCG release by a user node according to an example embodiment .

[0068] Like references are used to designate like parts in the accompanying drawings .DETAILED DESCRIPTION

[0069] Reference will now be made in detail to example embodiments , examples of which are illustrated in the accompanying drawings . The detai led description provided below in connection with the appended drawings is intended as a description of the present examples and is not intended to represent the only forms in which the present examples may be constructed or utili zed . The description sets forth the functions of the example and a possible sequence of operations for constructing and operating the example . However, the same or equivalent functions and sequences may be accomplished by di f ferent examples .

[0070] An obj ective is to manage subsequent PScell addition or change conditions such that a user node is configured to update an initial CPC condition for evaluation of candidate subsequent PScell addition or change configurations to a CPA condition to enable execution of the CPA upon or after a SCG release .

[0071] According to an example embodiment , a master node may be configured to configure a user node for a subsequent CPA before or during release of a SCG configuration . The user node may be enabled to update a CPC condition to achieve a CPA condition upon the SCG release . The CPC condition may be updated by updating a configured A3 / A5 condition to be partially applied for a subsequent CPA with measurements of a released PScell as a serving PScell , or by updating the A3 / A5 condition into a A4 condition . The method may enable a reduction of signal ling overhead and interrupting time forSCG change . When the user node is preconfigured with the CPA condition before the SCG release , the user node may evaluate the CPA condition for SCPAC configurations in advance and execute the CPA after a detected trigger, e . g . , based on a trigger provided by a network or based on detecting a single connectivity of the user node . Thi s enables , that i f the CPA condition is already met at the time of SCG release , it wil l save time for the user node to setup a new SCG link via executing the SCPAC configuration that met the CPA condition .

[0072] FIG . 1 illustrates an example of a communication system 100 comprising network nodes and at least one client node . The communication system 100 may comprise one or more base stations , such as gNBs . One of the base stations may act as a master node (MN) 104 . Further, one or more other base stations may act as secondary node ( SN) 106 . The communication system 100 may further comprise one or more client nodes , which may be also referred to as a user nodes or UE (user equipment ) . For example , the network may comprise a UE 102 . The UE 102 may communicate with one or more of the base stations via wireless radio channel ( s ) . Communications between UE 102 , MN 104 , and SN 106 may be bidirectional . Hence , any of the devices may be configured to operate as a transmitter and / or a receiver .

[0073] The base stations may be configured to communicate with core network elements , such as for example access and mobility management function (AMF) and / or user plane function (UPF) , over a communication interface , such as for example a control plane interface or a user plane interface NG-C / U . Base stations may be also called radio access network (RAN) nodes and they may be part o f a radio access network between the core network and the UEs . Network elements AMF / UPF and gNB may be generally referred to as network nodes or network devices . Although depicted as a single device , a network node might not be a stand-alone device , but forexample a distributed computing system coupled to a remote radio head .

[0074] The communication system 100 may be configured for example in accordance with the 5th Generation digital cellular communication network, as defined by the 3rd Generation Partnership Proj ect ( 3GPP ) . In one example , the communication network 100 may operate according to 3GPP 5G- NR (new radio ) . It is however appreciated that example embodiments presented herein are not limited to thi s example network and may be applied in any present or future wireless or wired communication networks , or combinations thereof , for example other type of cellular networks , short-range wireless networks , broadcast or multicast networks , or the like .

[0075] Dual connectivity ( DC ) allows a UE to simultaneously transmit and receive data on multiple component carriers from two serving nodes or cell groups . Dual connectivity may be allowed between two serving nodes operating in the same technology, or operating in di f ferent radio access technologies (RATs ) . The UE 102 may be configured to communicate with the MN 104 and the SN 104 via air interfaces , and perform dual connectivity with a master cell group (MSG) and a secondary cell group ( SCG) . The MN 104 and the SN 106 may be configured to operate in the same RAT or in di f ferent RATs . A case wherein the nodes are operating in di f ferent radio access technologies may be referred to as Multi-RAT dual connectivity . Example configurations of multi-radio dual connectivity (MR-DC ) include EN-DC (E-UTRA - NR Dual Connectivity) , NR-DC (New Radio Dual Connectivity) , NGEN-DC (NG-RAN - E-UTRA Dual Connectivity) and NE-DC (NR - E- UTRA Dual Connectivity) .

[0076] In MR-DC, a MN may refer to a radio access node configured to provide a control plane connection to the core network . The master node may be , for example , a master gNB .A master cell group (MCG) may refer to a group of serving cells associated with the master node . A secondary cell group ( SCG) may refer to a group of serving cells associated with a secondary node . The secondary node may refer to a radio access node without a control place connection to the core network . The secondary node may be configured to provide additional resources to a UE . The secondary node may be , for example , a secondary gNB . Each network node may have their own radio resource control (RRC ) entity, which may generate RRC protocol data units ( PDUs ) to be sent to the UE . A primary secondary cell ( PScell ) may refer to a secondary cell group cell in which a UE performs random access when performing reconfiguration with a sync procedure .

[0077] SCG reconfiguration may be performed through a RRC reconfiguration procedure . A RRC reconfiguration message may comprise conditional reconfiguration . A conditional reconfiguration may include configurations of one or more candidate cells and one or more execution conditions . The conditional reconfiguration may be for at least one of conditional a handover ( CHO, e . g . , change of a primary cell ) , a conditional PScell change ( CPC ) or a conditional PScell addition ( CPA) . A conditional reconfiguration procedure may be executed by a UE when the UE has evaluated that one or more execution conditions associated with the conditional reconfiguration are met . When the one or more execution conditions are met , the UE may be configured to connect to a target cell .

[0078] For example , a mobility procedure preconfigured to the UE that changes the UE ' s PScell may be referred to as the conditional PScell change ( CPC ) . During CPC, the UE may be configured to change SCG configuration from one cell group to another cell group, wherein PScell of each SCG may be di f ferent . The UE may execute the CPC once a predefined execution condition is met . The execution condition maycomprise, for example, one or more measurement events, such as a A3 event or a A5 event if the condition is determined by the SN. The event A3 is met when a neighbour PScell becomes offset better than serving PScell based on measurement results (e.g., RSRP) of the respective cells and an offset parameter defined for the event. The event A5 is met when a serving PScell becomes worse than a first threshold based on a measurement result of the respective cell (e.g., RSRP) and a neighbour PScell becomes better than a second threshold based on a measurement result of the respective cell (e.g., RSRP) . The A3 and A5 events may be configured as defined in TS 38.331. The events or conditions A3 and A5 may be evaluated by the UE by using serving SN measurement configurations.

[0079] For example, the UE may receive RRC reconfiguration message with CPC configuration and start to evaluate the CPC execution conditions for candidate PScell (s) . If at least one CPC candidate PScell satisfies the corresponding CPC execution condition, the UE completes the CPC execution procedure. The UE detaches from the source PScell, applies the stored corresponding configuration and synchronizes to the selected candidate PScell, i.e. a target PScell. Source PScell may be comprised in the source SCG controlled by a source SN. The target PScell may be comprised in the target SCG controlled by a target SN.

[0080] Type of the CPC may be either intra-SN CPC or inter-SN CPC, for example. In intra-SN CPC, the SN configured to control a secondary cell group (SCG) of the UE may be configured to stay the same. In other words, the source SN, or the SN controlling the source SCG, is the same as a target SN, i.e. the SN controlling the target SCG.

[0081] In inter-SN CPC, the SN controlling the SCG of the UE changes. In other words, the source SN, or the SN controlling the source SCG before the CPC execution isdifferent than a target SN controlling the target SCG after the CPC execution. For SN initiated inter-SN SCG selective activation, the source SN may be configured to generate the execution conditions for the initial CPC. Further, a candidate SN may be configured to generate execution conditions for subsequent CPC.

[0082] CPAC (conditional PScell addition or change) may be defined as the UE having network configuration for initiating access to a candidate PScell, either to consider the PScell as suitable for SN addition or SN change based on configured condition (s) . SCPAC may refer to a subsequent CPAC after an initial CPAC is performed. For example, the subsequent CPAC may refer to any CPAC after the initial CPAC. (S)CPAC execution condition and / or candidate PScell configuration can be updated, for example, by modifying the existing condition configurations. One or more candidate PScells may be configured in one or more radio resource control messages.

[0083] For a MN-initiated subsequent CPAC, the execution condition configuration may be provided as follows, for example :

[0084] a MN may be configured to generate the execution conditions (e.g., A4 event) for initial CPAC execution, and a measurement identifier may refer to the measurement configuration associated with MCG;

[0085] a candidate SN may be configured to generate the execution conditions (e.g., A3 / A5 event) for subsequent CPC execution, and the measurement identifier may refer to the measurement configuration associated with SCG.

[0086] CPA may refer to a situation where the UE does not have any SCG configuration and adds a SCG configuration. The UE may therefore move from a single connectivity to a dual connectivity. In case of CPA, the execution condition can be determined by the MN (as there is no SN) and can be configuredwith A4 event. The event A4 is met when a neighbour PScell becomes better than a threshold. For example, a signal level (refefence signal received power, RSRP) or quality (reference signal received quality, RSRQ) of the neighbor PScell may be above a threshold set for the RSRP or RSRQ. Before comparison of the signal level or quality with the threshold, a cell individual offset, a frequency-specific offset and hysteresis may be considered. This event A4 may be evaluated by the UE by using serving MN measurement configurations. A CPA conditional configuration can be used for CPC, but with different triggering conditions.

[0087] For example, when the execution condition of a CPC candidate PScell is met, the UE may be configured to perform the execution of CPC towards this candidate PScell. After finishing the PScell change, the UE may not release conditional configuration of other candidate PScells for subsequent CPC, and the UE may continue evaluating the execution conditions of other candidate PScells. When the execution condition of a candidate PScell is met, the UE may perform the execution of CPC towards this candidate PScell.

[0088] If the serving SCG is released, the UE may release the SCG measurement configurations and conditions. This creates a problem for execution of the candidate SCPAC configurations as the UE may not be able to determine execution of the candidate configurations without any condition. In an embodiment, the UE may be configured to modify at least one execution condition used for PScell change for at least one execution condition to be used for a PScell addition.

[0089] According to an example embodiment, the UE 102 may be configured for a subsequent CPA conditional configuration evaluation by a network node, i.e., the MN 104. In an example embodiment, a common measurement configuration and a A4 condition may be defined for all candidate subsequentconditional PScell addition / change configurations (a common A4 CPA measurement configuration) . This common A4 CPA measurement configuration may be, for example, preconfigured, e.g. during a CPC preparation. The common A4 CPA measurement configuration may be configured to be part of an MCG configuration. Pre-conf iguration of the execution conditions (A4 conditions) enables the UE to start evaluation of the execution conditions already before SCG release. Responsive to the SCG release, the UE 102 may be configured to start evaluating the A4 condition for retained SCPAC configurations. Alternatively, this may be controlled by the network, i.e., the network is configured to indicate to activate / deactivate the common A4 condition evaluation.

[0090] The UE 102 may be configured to perform the evaluation of common A4 condition continuously. However, if the condition is met, the UE 102 may be configured to execute the candidate SCPAC configuration if it is indicated by the network. Alternatively, the UE 102 may be configured to execute the candidate SCPAC configuration if the UE 102 is in single connectivity.

[0091] In an embodiment, instead of a common configuration, the MN 104 may be configured to provide a candidate PScell specific A4 condition and measurement configurations for the UE 102.

[0092] In an embodiment, the MN 104 may be configured to provide the A4 conditions and measurement configurations to the UE 102 responsive to the SCG release, e.g. at the time of the SCG release. For example, the A4 conditions configuration may be part of the measurement configurations. The UE 102 may be configured to release the SCG configuration and all relevant measurement configurations and related conditions. For example, the UE 102 may be configured to release at least one of initial or subsequent CPC condition configurations. The UE 102 may be configured to apply themeasurement configurations and A4 conditions provided by the MN 104 for the SCPAC candidate configurations retained after the SCG release . This enables , that the UE 102 may use the measurement configurations and conditions from the MN 104 even though the CPACs are subsequent CPACs , i . e . , even after the initial CPC was executed .

[0093] In an embodiment , upon a SCG release , the SCG configuration may be released, whereas the measurement configuration used for the candidate PScell configurations ( S-CPAC configurations ) can still be maintained ( i . e . , not released) at the UE . Hence , the UE 102 may continue evaluating a A3 / A5 execution condition for other candidate SNs for CPA ( in order to add a new SN) using measurement configuration of released SCG along with the PScell measurements of the released PScell . In this solution, a partial release mechanism on the UE side may be needed . In the partial release , the UE 102 may be configured to release SCG configuration but maintain the measurement configurations associated with the released SCG . The UE 102 may be configured to continue evaluation of the A3 / A5 execution condition, using the released PScell measurements for serving PScell measurements defined in A3 / A5 .

[0094] In case of SCG release , CPA may not be evaluated for the released SCG . Hence , the MN 104 may be configured to instruct the UE 102 to suspend evaluation of the released SCG . For example , the MN 104 may be configured to instruct the UE 102 to start a timer upon SCG release and upon expiry of the timer, the recent released SCG / PScell can be evaluated for CPA by the UE 102 .

[0095] Alternatively, the suspension instructions may comprise to mark after SCG release the corresponding conditional configuration as deactivated for that PScell . As part of the conditional configuration deactivation, CPA execution condition may not be evaluated for this releasedPScell. Upon DC, i.e. addition of another PScell, the conditional configuration of the released PScell may be configured to be marked as activated by the UE 102. Then, the CPC / CPA conditional evaluation can be started for the released PScell. The suspension instructions may be received by the UE 102, for example, in a RRC reconfiguration message received from the MN 104 for the SCG release.

[0096] FIG. 2 illustrates an example of an apparatus 200 configured to practice one or more example embodiments. The apparatus 200 may comprise, for example, a client node, such as for example the UE 102, or a network node, such as for example the master node 104, and configured to perform respective functionalities of the UE 102 or the master node 104 described herein.

[0097] The apparatus 200 may comprise at least one processor 202. The at least one processor 202 may comprise, for example, one or more of various processing devices, such as for example a co-processor, a microprocessor, a controller, a digital signal processor (DSP) , a processing circuitry with or without an accompanying DSP, or various other processing devices including integrated circuits such as, for example, an application specific integrated circuit (ASIC) , a field programmable gate array (FPGA) , a microcontroller unit (MCU) , a hardware accelerator, a special-purpose computer chip, or the like.

[0098] The apparatus 200 may further comprise at least one memory 204. The memory 204 may be configured to store, for example, computer program code 206 or the like, for example operating system software and application software. The memory 204 may comprise one or more volatile memory devices, one or more non-volatile memory devices, and / or a combination thereof. For example, the memory 204 may be embodied as magnetic storage devices (such as hard disk drives, magnetic tapes, etc.) , optical magnetic storagedevices , or semiconductor memories ( such as mask ROM, PROM (programmable ROM) , EPROM ( erasable PROM) , flash ROM, RAM ( random access memory) , etc . ) .

[0099] The apparatus 200 may further comprise one or more communication interfaces 208 configured to enable apparatus 200 to transmit and / or receive information, to / from other apparatuses . The communication interface 208 may be configured to provide at least one wireless radio connection, such as for example a 3GPP mobile broadband connection ( e . g . 3G, 4G, 5G or beyond) . However, the communication interface 208 may be configured to provide one or more other type of connections , for example a wireless local area network (WLAN) connection such as for example standardi zed by IEEE 802 . 11 series or Wi-Fi alliance ; a short range wireless network connection such as for example a Bluetooth, NFC (near- field communication) , or RFID connection; a wired connection such as for example a local area network ( LAN) connection, a universal serial bus (USB ) connection or an optical network connection, or the like ; or a wired Internet connection . The communication interface 208 may comprise , or be configured to be coupled to , at least one antenna to transmit and / or receive radio frequency signals . One or more of the various types of connections may be also implemented as separate communication interfaces , which may be coupled or configured to be coupled to a plurality of antennas .

[0100] The apparatus 200 may further comprise a user interface comprising an input device and / or an output device . The input device may take various forms such a keyboard, a touch screen, or one or more embedded control buttons . The output device may for example comprise a display, a speaker, a vibration motor, or the like .

[0101] When the apparatus 200 is configured to implement some functionality, some component and / or components of the apparatus 200 , such as for example the at least one processor202 and / or the memory 204, may be configured to implement this functionality. Furthermore, when the at least one processor 202 is configured to implement some functionality, this functionality may be implemented using instructions of program code 206 comprised, for example, in the memory 204.

[0102] The functionality described herein may be performed, at least in part, by one or more computer program product components such as software components. According to an embodiment, the apparatus 200 comprises a processor or processor circuitry, such as for example a microcontroller, configured by the program code when executed to execute the embodiments of the operations and functionality described. Alternatively, or in addition, the functionality described herein can be performed, at least in part, by one or more hardware logic components. For example, and without limitation, illustrative types of hardware logic components that can be used include Field-programmable Gate Arrays (FPGAs) , application-specific Integrated Circuits (ASICs) , application-specific Standard Products (ASSPs) , System-on- a-chip systems (SOCs) , Complex Programmable Logic Devices (CPLDs) , Graphics Processing Units (GPUs) .

[0103] The apparatus 200 may comprise means for performing at least one method described herein. In one example, the means comprises the at least one processor 202, the at least one memory 204 including instructions (e.g., the program code 206) configured to, when executed by the at least one processor 202, cause the apparatus 200 to perform the method.

[0104] The apparatus 200 may comprise for example a computing device such as for example a base station, a network node, a server device, a client node, a mobile phone, a tablet computer, a laptop, or the like. Although the apparatus 200 is illustrated as a single device it isappreciated that , wherever applicable , functions of apparatus 200 may be distributed to a plurality of devices .

[0105] The apparatus 200 may be configured to manage SCPAC condition ( s ) upon a SCG release . The apparatus 200 may be configured to at least send or receive instructions for applying one or more execution conditions by a user node for a subsequent CPA after the SCG release . The instructions may comprise at least one of updating the execution conditions to a common A4 condition and measurement configuration for all candidate SCPAC configuration evaluations , to a list of A4 conditions and measurement configurations speci fic for each candidate SCPAC configuration evaluation or to continue evaluations with current CPC conditions with released PScell measurements as a serving PScell after the SCG release .

[0106] FIG . 3 illustrates an example of a message sequence chart for managing SCPAC condition upon SCG release according to an example embodiment . The UE 102 may be preconfigured with the at least one execution condition for CPA for subsequent CPAC condition evaluation . The preconfiguration may be performed, for example , during CPC preparation . The UE 102 may be also preconfigured with measurement configurations for the CPA. The UE 102 may evaluate i f the at least one execution condition is met before , during and / or after the SCG release . However, even i f the evaluation is performed before the SCG release , the UE 102 may be configured to perform execution of the CPA upon or after the SCG release . The execution of the CPA based on the evaluation may be triggered based on an indication for activation received from the master node . Alternatively, the execution of the CPA based on the evaluation may be triggered when the UE 102 is in single connectivity .

[0107] At 300 , a user node , such as the UE 102 , may be configured to send a measurement to a S-SN 106A ( servingsecondary node) . The S-SN 106A may be configured to initiate inter-SN SCPAC based on the received measurement report.

[0108] At 302, the S-SN 106A may be configured to send a message indicative of a required SN change to a MN 104. The message may comprise initial CPC conditions (e.g., a A3 / A5 event condition) .

[0109] At 304, the MN 104 may be configured to send a request for SN addition to a T-SN-1 106B (a first target secondary node) . At 306, the MN 104 may be configured to send a request for SN addition to a T-SN-2 106C (a second target secondary node) . At 308, the MN 104 may be configured to send the request for SN addition to other potential target secondary nodes, such as to one or more T-SN-Ns 106D. The S- SN 106A, T-SN-1 106B, T-SN-2 106C, T-SN-N may be SNs 106 of a SCG.

[0110] At 310, the MN 104 may be configured to receive a response from the T-SN-1 106B. The T-SN-1 106B may be configured to respond with a SN addition request acknowledgement message. The response may comprise subsequent CPC conditions (e.g., A3 / A5 even conditions) .

[0111] At 312, the MN 104 may be configured to receive a response from the T-SN-2 106C. The T-SN-2 106C may be configured to respond with a SN addition request acknowledgement message. The response may comprise subsequent CPC conditions (e.g., A3 / A5 even conditions) .

[0112] At 314, the MN 104 may be configured to receive a response from the other potential T-SN(s) . For example, the one or more T-SN-Ns 106D may be configured to respond with a SN addition request acknowledgement message. The response may comprise subsequent CPC conditions (e.g., A3 / A5 even conditions) .

[0113] At 316, the MN 104 may be configured to send a RRC reconfiguration message to the UE 102. The RRC configuration message may comprise at least one of the initial conditions(A3 / A5 ) , a list of the subsequent CPC conditions of T-SN- 1 , T-SN-2 and / or the one or more T-SN-Ns , one or more execution conditions for CPA to be applied for SCPAC evaluation, or an indication to deactivate the one or more execution conditions for CPA.[001 14] The one or more execution conditions may comprise a common A4 CPA condition and measurement configuration for all candidate SCPAC configurations . Alternatively, the one or more execution conditions may comprise a list of A4 CPA conditions and measurement configurations per candidate SCPAC configuration . Hence , the UE 102 may be configured to perform evaluation for a subsequent CPA based on a A4 event condition and measurement conditions which is common for all candidate SCPAC configurations or based on a A4 event condition and measurement configurations speci fic for each candidate SCPAC configuration . The measurement configurations may be mapped to an MSG configuration .[001 1 5] At 318 , the UE 102 may be configured to register the one or more execution conditions ( the common A4 CPA condition or the list of A4 CPA conditions ) for SCPAC execution in a deactivated state . The UE 102 may be further configured to evaluate the initial CPC conditions ( e . g . , the A3 / A5 event ) .[001 16] At 320 , the UE 102 may be configured to send a response to the RRC configuration message received at 316 from the MN 104 . The UE 102 may be configured to respond to the MN 104 with a message indicating that the RRC configuration is completed .[001 1 7] At 322 , the MN 104 may be configured to send a confirmation message to the S-SN 106A of the SN change .[001 18] At 324 , the MN 104 may be configured to send a request for SN release to the S-SN 106A. The request may be sent due to a throughput requirement or load being low (below a predetermined threshold) , and hence , the SN / DC may not berequired anymore. Alternatively, the request may be sent due to a link between the UE 102 and the source SN not being strong anymore (e.g., a parameter value indicative of the strength of the link being below a certain threshold) , and therefore, the link may be released before any failure.

[0119] At 326, the S-SN 106A may be configured to reply to the MN 104 with a SN release request acknowledgement.

[0120] At 328, the MN 104 may be configured to send a RRC reconfiguration message to the UE 102 for SCG release. The RRC reconfiguration message may comprise an indication to activate the one or more execution conditions, i.e., the common A4 CPA condition or the list of A4 CPA conditions.

[0121] At 330, the UE 102 may be configured to execute the SCG release procedure. For example, in case the SCG release is performed before an initial CPC execution, the UE 102 may be configured to at least one of release SCG configuration, release measurement configurations of the initial CPC conditions, release the initial CPC conditions or activate the common A4 CPA condition / list of A4 CPA conditions for SCPAC evaluation.

[0122] At 332, the UE 102 may be configured to reply to the RRC reconfiguration message received from the MN 104 at 328, the response indicating that the RRC reconfiguration has been completed.

[0123] The SCG may also be released after the initial CPC execution. For example, the UE 102 may be configured to execute SCPAC configuration of T-SN-1 106B when T-SN-1 CPC condition is met, at 334. At 336, a RACH (random access channel) procedure is performed by the UE 102 with the T-SN- 1 106B.

[0124] At 338, the UE 102 may be configured to start evaluating the subsequent CPC conditions (A3 / A5) of the T- SN-1 106B.

[0125] At 340 , the UE 102 may be configured to send a message to the MN 104 indicating that RRC reconfiguration has been completed . The message comprises an indication that SN reconfiguration has been completed .

[0126] At 342 , the MN 104 may be configured to send a SN release request to the T-SN- 1 106B . The SN release request may be configured to be sent due to the throughput requirement or throughput load being low . Hence , the SN / DC may not be required . Alternatively, the SN release request may be configured to be sent due to the link between the UE 102 and the source SN not being strong anymore .

[0127] At 344 , the T-SN- 1 106B may be configured to send a response to the MN 104 , acknowledging the SN release request received at 342 .

[0128] At 346 , the MN 104 may be configured to send a RRC reconfiguration message to the UE 102 for SCG release . The RRC reconfiguration message may comprise an indication to activate the common A4 CPA condition or the list of A4 CPA conditions indicated at 316 .

[0129] At 348 , the UE 102 may be configured to execute the SCG release procedure . In the case of SCG release after execution of the initial CPC execution, the UE 102 may be configured to at least one of release SCG configuration, release measurement configurations of the subsequent CPC conditions , release the subsequent CPC conditions or activate the common A4 CPA condition / the list of A4 CPA conditions for SCPAC evaluation .[001 30] At 350 , the UE 102 may be configured to send a response to the RRC reconfiguration message received at 346 from the MN 104 to inform the MN 104 that the RRC reconfiguration has been completed .[001 31 ] At 352 , the UE 102 may be configured to use MCG measurement configurations and evaluate the common A4 CPAcondition for all candidate SCPAC configurations. Alternatively, the UE 102 may be configured to use the MCG measurement configurations and evaluate the list of A4 CPA conditions for each candidate SCPAC configurations.

[0132] At 354, the UE 102 may be configured to execute T- SN-2 SCPAC configuration upon detecting that T-SN-2 CPA condition is met.

[0133] At 356, the UE 102 may be configured to perform a RACH procedure with the T-SN-2 106C.

[0134] FIG. 4 illustrates another example of a message sequence chart for managing SCPAC condition upon SCG release according to an example embodiment. Here, instead of preconfiguring the UE 102 with the one or more execution conditions for subsequent CPA before the SCG release, the master node 104 may be configured to indicate the one or more execution conditions for CPC to CPA conversion for SCPAC evaluations during the SCG release. Corresponding operations in FIG. 3 and FIG. 4 are indicated with corresponding reference numbers.

[0135] At 300, the UE 102 may be configured to send a measurement report to a S-SN 106A. The S-SN 106A may be configured to initiate inter-SN SCPAC based on the received measurement report.

[0136] At 302, the S-SN 106A may be configured to send a message indicative of a required SN change to the MN 104. The message may comprise initial CPC conditions (e.g., a A3 / A5 event condition) .

[0137] At 304, the MN 104 may be configured to send a request for SN addition to a T-SN-1 106B. At 306, the MN 104 may be configured to send a request for SN addition to a T- SN-2 106C. At 308, the MN 104 may be configured to send the request for SN addition to other potential target secondary nodes, such as to one or more T-SN-Ns 106D.

[0138] At 310, the MN 104 may be configured to receive a response from the T-SN-1 106B. The T-SN-1 106B may be configured to respond with a SN addition request acknowledgement message. The response may comprise subsequent CPC conditions (e.g., A3 / A5 even conditions) .

[0139] At 312, the MN 104 may be configured to receive a response from the T-SN-2 106C. The T-SN-2 106C may be configured to respond with a SN addition request acknowledgement message. The response may comprise subsequent CPC conditions (e.g., A3 / A5 even conditions) .

[0140] At 314, the MN 104 may be configured to receive a response from the other potential T-SN(s) . For example, the one or more T-SN-Ns 106D may be configured to respond with a SN addition request acknowledgement message. The response may comprise subsequent CPC conditions (e.g., A3 / A5 even conditions) .

[0141] At 400, the MN 104 may be configured to send a RRC reconfiguration message to the UE 102. The RRC configuration message may comprise at least one of the initial conditions (A3 / A5) (of S-SN 106A) or a list of the subsequent CPC conditions of T-SN-1 106B, T-SN-2 106C and / or the one or more T-SN-Ns 106D.

[0142] At 402, the UE 102 may be configured to evaluate the initial CPC conditions (e.g., the A3 / A5 event) .

[0143] At 404, the UE 102 may be configured to send a response to the RRC configuration message received at 400 from the MN 104. The UE 102 may be configured to respond to the MN 104 with a message indicating that the RRC configuration is completed.

[0144] At 322, the MN 104 may be configured to send a confirmation message to the S-SN 106A of the SN change.

[0145] At 324, the MN 104 may be configured to send a request for SN release to the S-SN 106A. The request may besent due to a throughput requirement or load being low (below a predetermined threshold) , and hence , the SN / DC may not be required anymore . Alternatively, the request may be sent due to a link between the UE 102 and the source SN not being strong anymore ( e . g . , a parameter value indicative of the strength of the link being below a certain threshold) , and therefore , the link may be released before any failure .

[0146] At 326 , the S-SN 106A may be configured to reply to the MN 104 with a SN release request acknowledgement .

[0147] At 406 , the MN 104 may be configured to send a RRC reconfiguration message to the UE 102 for SCG release . The RRC reconfiguration message may comprise one or more execution conditions for a subsequent CPA. The one or more execution conditions may comprise a common A4 CPA condition and measurement configuration for all candidate SCPAC configurations . Alternatively, the one or more execution conditions may comprise a list of A4 CPA conditions and measurement configurations per candidate SCPAC configuration . Hence , the UE 102 may be configured to perform evaluation for a subsequent CPA based on a A4 event condition and measurement conditions which is common for al l candidate SCPAC configurations or based on a A4 event condition and measurement configurations speci fic for each candidate SCPAC configuration . The measurement configurations may be mapped to an MSG configuration .

[0148] At 408 , the UE 102 may be configured to execute the SCG release procedure . For example , in case the SCG release is performed before an initial CPC execution, the UE 102 may be configured to at least one of release SCG configuration, release measurement configurations of the initial CPC conditions , release the initial CPC conditions or apply the common A4 CPA condition / list of A4 CPA conditions for SCPAC evaluation .

[0149] At 410, the UE 102 may be configured to reply to the RRC reconfiguration message received from the MN 104 at 406, the response indicating that the RRC reconfiguration has been completed.

[0150] The SCG may also be released after the initial CPC execution. For example, the UE 102 may be configured to execute SCPAC configuration of T-SN-1 106B when T-SN-1 CPC condition is met, at 334. At 336, a RACH (random access channel) procedure is performed by the UE 102 with the T-SN- 1 106B.

[0151] At 338, the UE 102 may be configured to start evaluating the subsequent CPC conditions (A3 / A5) of the T- SN-1 106B.

[0152] At 340, the UE 102 may be configured to send a message to the MN 104 indicating that RRC reconfiguration has been completed. The message comprises an indication that SN reconfiguration has been completed.

[0153] At 342, the MN 104 may be configured to send a SN release request to the T-SN-1 106B. The SN release request may be configured to be sent due to the throughput requirement or throughput load being low. Hence, the SN / DC may not be required. Alternatively, the SN release request may be configured to be sent due to the link between the UE 102 and the source SN not being strong anymore.

[0154] At 344, the T-SN-1 106B may be configured to send a response to the MN 104, acknowledging the SN release request received at 342.

[0155] At 412, the MN 104 may be configured to send a RRC reconfiguration message to the UE 102 for SCG release. The RRC reconfiguration message may comprise the one or more execution conditions to be applied by the UE 102 for subsequent CPA, such as the common A4 CPA condition or the list of A4 CPA conditions.[001 56] At 414 , the UE 102 may be configured to execute the SCG release procedure . In the case of SCG release after execution of the initial CPC execution, the UE 102 may be configured to at least one of release SCG configuration, release measurement configurations of the subsequent CPC conditions , release the subsequent CPC conditions or apply the common A4 CPA condition / the list of A4 CPA conditions for SCPAC evaluation .[001 57] At 416 , the UE 102 may be configured to send a response to the RRC reconfiguration message received at 412 from the MN 104 to inform the MN 104 that the RRC reconfiguration has been completed .[001 58] At 352 , the UE 102 may be configured to use MCG measurement configurations and evaluate the common A4 CPA condition for all candidate SCPAC configurations . Alternatively, the UE 102 may be configured to use the MCG measurement configurations and evaluate the list of A4 CPA conditions for each candidate SCPAC configurations .[001 59] At 354 , the UE 102 may be configured to execute T- SN-2 SCPAC configuration upon detecting that T-SN-2 106C CPA condition is met .

[0160] At 356 , the UE 102 may be configured to perform a RACH procedure with the T-SN-2 106C .

[0161] FIG . 5 illustrates an example of a message sequence chart for managing SCPAC condition with a partial release of a previous condition upon SCG release according to an example embodiment . Here , instead of indicating the A4 CPA condition ( s ) to be used for the subsequent CPA evaluation / execution, the master node 104 may be configured to instruct the UE 102 to perform a partial release of the initial or subsequent CPC conditions for evaluating candidate SCPAC configurations . Operations corresponding to operations in previous figures are illustrated with the same reference numbers .

[0162] At 300, the UE 102, may be configured to send a measurement report to a S-SN 106A. The S-SN 106A may be configured to initiate inter-SN SCRAG based on the received measurement report.

[0163] At 302, the S-SN 106A may be configured to send a message indicative of a required SN change to the MN 104. The message may comprise initial CPC conditions (e.g., a A3 / A5 event condition) .

[0164] At 304, the MN 104 may be configured to send a request for SN addition to a T-SN-1 106B. At 306, the MN 104 may be configured to send a request for SN addition to a T- SN-2 106C. At 308, the MN 104 may be configured to send the request for SN addition to other potential target secondary nodes, such as to one or more T-SN-Ns 106D.

[0165] At 310, the MN 104 may be configured to receive a response from the T-SN-1 106B. The T-SN-1 106B may be configured to respond with a SN addition request acknowledgement message. The response may comprise subsequent CPC conditions (e.g., A3 / A5 even conditions) .

[0166] At 312, the MN 104 may be configured to receive a response from the T-SN-2 106C. The T-SN-2 106C may be configured to respond with a SN addition request acknowledgement message. The response may comprise subsequent CPC conditions (e.g., A3 / A5 even conditions) .

[0167] At 314, the MN 104 may be configured to receive a response from the other potential T-SN(s) . For example, the one or more T-SN-Ns 106D may be configured to respond with a SN addition request acknowledgement message. The response may comprise subsequent CPC conditions (e.g., A3 / A5 even conditions) .

[0168] At 500, the MN 104 may be configured to send a RRC reconfiguration message to the UE 102. The RRC configuration message may comprise at least one of the initial conditions(A3 / A5) (of the S-SN 106A) or a list of the subsequent CPC conditions of T-SN-1 106B, T-SN-2 106C and / or the one or more T-SN-Ns 106D. Optionally, the reconfiguration message may further comprise an indication to perform a partial release of relevant CPC conditions (A3 / A5) in case of a SCG release. The indication may comprise instructions to continue with the CPC conditions after the SCG release with released PScell measurements as serving PScell measurements for SCPAC evaluation. The released PScell measurements may be treated as serving PScell measurements.

[0169] At 502, the UE 102 may be configured to evaluate the initial CPC conditions (e.g., the A3 / A5 event) . The UE 102 may be further configured to store the instructions to be applied upon the SCG release.

[0170] At 504, the UE 102 may be configured to send a response to the RRC configuration message received at 500 from the MN 104. The UE 102 may be configured to respond to the MN 104 with a message indicating that the RRC configuration is completed.

[0171] At 322, the MN 104 may be configured to send a confirmation message to the S-SN 106A of the SN change.

[0172] At 324, the MN 104 may be configured to send a request for SN release to the S-SN 106A. The request may be sent due to a throughput requirement or load being low (below a predetermined threshold) , and hence, the SN / DC may not be required anymore. Alternatively, the request may be sent due to a link between the UE 102 and the source / serving SN not being strong anymore (e.g., a parameter value indicative of the strength of the link being below a certain threshold) , and therefore, the link may be released before any failure.

[0173] At 326, the S-SN 106A may be configured to reply to the MN 104 with a SN release request acknowledgement.

[0174] At 506, the MN 104 may be configured to send a RRC reconfiguration message to the UE 102 for SCG release. TheRRC reconfiguration message may comprise the indication to perform the one or more execution conditions, i.e., the partial release of relevant CPC (A3 / A5) conditions (if not already indicated at 500) . For example, the reconfiguration message may comprise instructions for the UE 102 to continue evaluation of the A3 / A5 events and to use released PScell measurements as serving PScell measurements for the A3 / A5 evaluation. The released PScell measurements may be treated as serving PScell measurements.

[0175] At 508, the UE 102 may be configured to execute the SCG release procedure. For example, in case the SCG release is performed before an initial CPC execution, the UE may be configured to at least one of release SCG configuration, retain measurement configurations of the initial CPC conditions, retain the initial CPC conditions, or continue evaluation of the initial CPC conditions for retained (candidate) SCPAC configurations using the released PScell measurements as serving PScell measurements, based on the instructions received from the master node in at least one of operation 500 or 506.

[0176] At 510, the UE 102 may be configured to reply to the RRC reconfiguration message received from the MN 104 at 506, the response indicating that the RRC reconfiguration has been completed.

[0177] The SCG may also be released after the initial CPC execution. For example, the UE 102 may be configured to execute SCPAC configuration of T-SN-1 106B when T-SN-1 CPC condition is met, at 334. At 336, a RACH (random access channel) procedure is performed by the UE 102 with the T-SN- 1 106B.

[0178] At 338, the UE 102 may be configured to start evaluating the subsequent CPC conditions (A3 / A5) of the T- SN-1 106B.[001 79] At 340 , the UE 102 may be configured to send a message to the MN 104 indicating that RRC reconfiguration has been completed . The message comprises an indication that SN reconfiguration has been completed .

[0180] At 342 , the MN 104 may be configured to send a SN release request to the T-SN- 1 106B . The SN release request may be configured to be sent due to the throughput requirement or throughput load being low . Hence , the SN / DC may not be required . Alternatively, the SN release request may be configured to be sent due to the link between the UE and the source SN not being strong anymore .

[0181] At 344 , the T-SN- 1 106B may be configured to send a response to the MN 104 , acknowledging the SN release request received at 342 .

[0182] At 512 , the MN 104 may be configured to send a RRC reconfiguration message to the UE 102 for SCG release . The RRC reconfiguration message may comprise the indication to perform the one or more execution conditions , i . e . , the partial release of relevant CPC (A3 / A5 ) conditions ( i f not already indicated at 500 ) . For example , the reconfiguration message may comprise instructions for the UE 102 to continue evaluation of the A3 / A5 events and to use released PScell measurements as serving PScell measurements for the A3 / A5 evaluation .

[0183] At 514 , the UE 102 may be configured to execute the SCG release procedure . In the case of SCG release after execution of the initial CPC execution, the UE 102 may be configured to at least one of retain SCG configuration, retain measurement configurations of the subsequent CPC conditions , retain the subsequent CPC conditions or continue evaluation of the initial CPC conditions for retained SCPAC configurations using the released PScell measurements as serving PScell measurements , based on the instructionsreceived from the master node in at least one of operation 500 or 512 .

[0184] At 516 , the UE 102 may be configured to send a response to the RRC reconfiguration message received at 512 from the MN 104 to inform the MN that the RRC reconfiguration has been completed .

[0185] At 518 , the UE 102 may be configured to use SCG measurement configurations of released SCG to evaluate the one or more A3 / A5 conditions for each candidate SCRAG configurations for CPA, wherein the released PScell measurements are used as the serving PScell for the A3 / A5 evaluation .

[0186] At 354 , the UE 102 may be configured to execute T- SN-2 SCRAG configuration upon detecting that T-SN-2 CPA condition is met .

[0187] At 356 , the UE 102 may be configured to perform a RACH procedure with the T-SN-2 106C .

[0188] FIG . 6 illustrates an example of a method 600 for managing SCRAG condition for CPA execution upon or after SCG release by a network node according to an example embodiment . The network node may comprise , for example , the master node 104 .

[0189] At 602 , the method may comprise sending, to a user node , at least one execution condition for a CPA to be applied by the user node for evaluation of a SCRAG condition for execution of CPA upon or after a secondary cell group, SCG, release . The at least one execution condition for CPA may be configured to replace at least one execution condition configured to the user node for evaluation of the SCRAG condition for a CPC .

[0190] FIG . 7 illustrates an example of a method 700 for managing SCRAG condition for CPA execution upon or after SCGrelease by a user node according to an example embodiment. The user node may comprise, for example, the UE 102.

[0191] At 702, the method may comprise receiving, from a master node, at least one execution condition for a conditional primary secondary cell, PScell, addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change, SCPAC, condition evaluation for execution of CPA upon or after a secondary cell group, SCG, release. The at least one execution condition for CPA may be configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change, CPC.

[0192] Further features of the methods, such as the method 600 or the method 700, directly result from the functionalities and parameters of the apparatuses, as described in the appended claims and throughout the specification and are therefore not repeated here. It is noted that one or more operations of the method may be performed in different order.

[0193] An apparatus, for example a network node, such as the master node 104, a user node or a client node, such as the UE 102, may be configured to perform or cause performance of any aspect of the method (s) described herein. Further, a computer program may comprise instructions for causing, when executed, an apparatus to perform any aspect of the method (s) described herein. Further, an apparatus may comprise means for performing any aspect of the method (s) described herein. According to an example embodiment, the means comprises at least one processor, and memory including program code, the at one memory and the program code configured to, when executed by the at least one processor, cause performance of any aspect of the method (s) .[001 94] Any range or device value given herein may be extended or altered without losing the ef fect sought . Also , any embodiment may be combined with another embodiment unless explicitly disallowed .[001 95] Although the subj ect matter has been described in language speci fic to structural features and / or acts , it is to be understood that the subj ect matter defined in the appended claims is not necessarily limited to the speci fic features or acts described above . Rather, the specific features and acts described above are disclosed as examples of implementing the claims and other equivalent features and acts are intended to be within the scope of the claims .[001 96] It will be understood that the benefits and advantages described above may relate to one embodiment or may relate to several embodiments . The embodiments are not limited to those that solve any or all of the stated problems or those that have any or all of the stated benefits and advantages . It will further be understood that reference to ' an ' item may refer to one or more of those items .[001 97] The operations of the methods described herein may be carried out in any suitable order, or simultaneously where appropriate . Additionally, individual blocks may be deleted from any of the methods without departing from the scope of the subj ect matter described herein . Aspects of any of the embodiments described above may be combined with aspects of any of the other embodiments described to form further embodiments without losing the ef fect sought .[001 98] The term ' comprising ' is used herein to mean including the method, blocks , or elements identi fied, but that such blocks or elements do not comprise an exclusive list and a method or apparatus may contain additional blocks or elements .[001 99] As used in this application, the term ' circuitry' may refer to one or more or all of the following : ( a)hardware-only circuit implementations (such as implementations in only analog and / or digital circuitry) and (b) combinations of hardware circuits and software, such as (as applicable) : (i) a combination of analog and / or digital hardware circuit (s) with software / firmware and (ii) any portions of hardware processor (s) with software (including digital signal processor ( s ) ) , software, and memory ( ies ) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and (c) hardware circuit (s) and or processor ( s ) , such as a microprocessor ( s ) or a portion of a microprocessor ( s ) , that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation. This definition of circuitry applies to all uses of this term in this application, including in any claims.

[0200] As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

[0201] It will be understood that the above description is given by way of example only and that various modifications may be made by those skilled in the art. The above specification, examples and data provide a complete description of the structure and use of exemplary embodiments. Although various embodiments have been described above with a certain degree of particularity, or with reference to one or more individual embodiments, those skilled in the art could make numerous alterations to thedisclosed embodiments without departing from scope of this specification.

Claims

CLAIMS1 . A master node , comprising : at least one processor ; and at least one memory including instructions which, when executed by the at least one proces sor, cause the master node at least to : send, to a user node , at least one execution condition for a conditional primary secondary cell , PScell , addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change , SCPAC, condition for execution of CPA to be performed after a secondary cell group, SCG, release , and wherein the at least one execution condition for CPA is configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change , CPC .2 . The master node of claim 1 , wherein the at least one execution condition for CPA comprises at least one A4 event condition mapped to a master cell group, MCG, configuration, wherein the at least one A4 event condition is defined for candidate SCPAC configurations .3 . The master node of claim 2 , wherein the at least one execution condition comprises one A4 event condition common for all candidate SCPAC configurations .4 . The master node of claim 2 , wherein the at least one execution condition comprises A4 event conditions speci fic for each candidate SCPAC configuration .5 . The master node of claim 1 , wherein the at leastone execution condition comprises instructions to maintain measurement configurations associated with the released SCG and SCPAC condition evaluation wherein the instructions instruct the user node to continue , after the SCG release , SCPAC condition evaluation based on at least one of A3 event condition or A5 event condition of the CPC with measurement configurations associated with the released SCG .6 . The master node of any of claims 1 to 4 , wherein the at least one memory comprises instructions which, when executed by the at least one proces sor, cause the master node to : send an indication to deactivate the at least one execution condition; detect a need for a SCG release ; and send a reconfiguration message for the SCG release comprising an indication to the user node to activate the at least one execution condition .7 . The master node of any of claims 1 to 5 , wherein the at least one execution condition is sent in a radio resource control , RRC, reconfiguration message for the SCG release .8 . The master node of any of claims 1 to 6 , wherein the at least one execution condition is sent in a radio resource control , RRC, reconfiguration message including at least one of an initial conditional PScell change , CPC , condition configuration or a subsequent CPC condition configuration .9 . The master node of any preceding claim, whereinthe at least one memory further comprises instructions which, when executed by the at least one proces sor, cause the master node to : send instructions to the user node to suspend evaluation of the at least one execution condition for the released SCG .10 . The master node of claim 9 , wherein the instructions sent to the user node comprise instructions to suspend the evaluation of the at least one execution condition for the released SCG for a certain period of time from the SCG release .11 . The master node of claim 9 , wherein the instructions sent to the user node comprise instructions to suspend the evaluation of the at least one execution condition for the released SCG until the user node executes at least one conditional PCell addition .12 . A user node , comprising : at least one processor ; and at least one memory including instructions which, when executed by the at least one processor , cause the user node at least to : receive , from a master node , at least one execution condition for a conditional primary secondary cell , PScell , addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change , SCPAC, condition for execution of CPA to be performed after a secondary cell group, SCG, release, wherein the at least one execution condition for CPA is configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change , CPC .13 . The user node of claim 12 , wherein the at least one execution condition for CPA comprises at least one A4 event condition mapped to a master cell group, MCG, configuration, wherein the at least one A4 event condition is defined for candidate SCPAC configurations .14 . The user of claim 13 , wherein the at least one execution condition for CPA comprises one A4 event condition common for all candidate SCPAC configurations .15 . The user node of claim 13 , wherein the at least one execution condition for CPA comprises A4 event conditions speci fic for each candidate SCPAC configuration .16 . The user node of any of claims 12 to 15 , wherein the at least one memory comprises instructions which, when executed by the at least one processor, cause the user node to : receive , from the master node , a reconfiguration message for SCG release ; perform the SCG release , comprising : releasing SCG configuration; releasing measurement configuration of at least one of an initial CPC condition or a subsequent CPC condition; releasing at least one of the CPC condition or the subsequent CPC condition; wherein the user node is caused to : evaluate the SCPAC condition based on the at least one execution condition for CPA; and after the SCG release , execute CPA based on the evaluating .17 . The user node of claim 16 , wherein the at leastone memory comprises instructions which, when executed by the at least one processor, cause the user node to : receive , from the master node , the at least one execution condition for CPA with an indication to deactivate the at least one execution condition for CPA; store the at least one execution condition in a deactivated state ; and receive , from the master node , the reconfiguration message for the SCG release with an indication to activate the at least one execution condition for CPA.18 . The user node of claim 12 , wherein the at least one execution condition for CPA comprises instructions to maintain measurement configurations associated with the released SCG and SCPAC condition evaluation wherein the instructions instruct the user node to continue , after the SCG release , SCPAC condition evaluation based on the at least one of A3 event condition or A5 event condition of the CPC with measurement configurations associated with the released SCG .19 . The user node of any of claims 12 to 18 , wherein the at least one execution condition for CPA is received in a radio resource control , RRC , reconfiguration message including at least one of an initial CPC condition configuration or a subsequent CPC condition configuration .20 . The user node of any of claims 12 to 18 , wherein the at least one execution condition for CPA is received in a RRC reconfiguration message for the SCG release .21 . The user node of any of claims 12 to 20 , whereinthe at least one memory further comprises instructions which, when executed by the at least one processor, cause the user node to : receive instructions from the master node to suspend evaluation of the at least one execution condition for CPA for the released SCG; and suspend the evaluation of the at least one execution condition for CPA for the released SCG according to the instructions .22 . The user node of claim 21 , wherein the instructions received from the master node comprise instructions to suspend the evaluation of the at least one execution condition for CPA for the released SCG for a certain period of time from the SCG release .23 . The user node of claim 21 , wherein the instructions received from the master node comprise instructions to suspend the evaluation of the at least one execution condition for CPA for the released SCG until the user node executes at least one conditional PCell addition .24 . The user node of any of claims 18 to 23 , wherein the at least one memory comprises instruction which, when executed by the at least one processor, cause the user node to : receive , from the master node , a reconfiguration message for SCG release before an initial conditional PScell change has been executed; perform the SCG release , comprising : releasing SCG configuration; maintaining measurement configurations of initial CPC conditions ; and maintaining initial CPC conditions ;wherein the user node is caused to : update the initial CPC conditions for CPA, wherein the initial CPC conditions are evaluated for candidate SCPAC configurations with released PScell measurements as serving PScell measurements ; and upon or after the SCG release , perform evaluation for the conditional PScell addition execution based on the update .25 . The user node of any of claims 18 to 23 , wherein the at least one memory comprises instruction which, when executed by the at least one processor, cause the user node to : receive , from the master node , a reconfiguration message for SCG release after an initial conditional PScell change has been executed; perform the SCG release , comprising : maintaining SCG configuration; maintaining measurement configurations of subsequent conditional PScell change , CPC , conditions ; maintaining subsequent CPC conditions ; and wherein the user node is caused to : update the subsequent CPC conditions for CPA, wherein the subsequent CPC conditions are evaluated for candidate SCPAC configurations with released PScell measurements as serving PScell measurements ; and upon or after the SCG release , perform evaluation for the conditional PScell addition execution based on the update .26 . A method to be carried out by a master node , comprising : sending, to a user node , at least one execution condition for a conditional primary secondary cell , PScell ,addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change , SCPAC, condition for execution of CPA to be performed after a secondary cell group, SCG, release , and wherein the at least one execution condition for CPA is configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change , CPC .27 . The method of claim 26 , wherein the at least one execution condition for CPA comprises at least one A4 event condition mapped to a master cell group, MCG, configuration, wherein the at least one A4 event condition is defined for candidate SCPAC configurations .28 . The method of claim 27 , wherein the at least one execution condition comprises one A4 event condition common for all candidate SCPAC configurations .29 . The method of claim 27 , wherein the at least one execution condition comprises A4 event conditions speci fic for each candidate SCPAC configuration .30 . The method of claim 26 , wherein the at least one execution condition comprises instructions to maintain measurement configurations associated with the released SCG and SCPAC condition evaluation wherein the instructions instruct the user node to continue , after the SCG release , SCPAC condition evaluation based on at least one of A3 event condition or A5 event condition of the CPC with measurement configurations associated with the released SCG .31 . The method of any of claims 26 to 29 , comprising :sending an indication to deactivate the at least one execution condition; detecting a need for a SCG release ; and sending a reconfiguration message for the SCG release comprising an indication to the user node to activate the at least one execution condition .32 . The method of any of claims 26 to 30 , wherein the at least one execution condition is sent in a radio resource control , RRC, reconfiguration message for the SCG release .33 . The method of any of claims 26 to 31 , wherein the at least one execution condition is sent in a radio resource control , RRC, reconfiguration message including at least one of an initial conditional PScell change , CPC, condition configuration or a subsequent CPC condition configuration .34 . The method of any of claims 26 to 33 , comprising : sending instructions to the user node to suspend evaluation of the at least one execution condition for the released SCG .35 . The method of claim 34 , wherein the instructions sent to the user node comprise instructions to suspend the evaluation of the at least one execution condition for the released SCG for a certain period of time from the SCG release .36 . The method of claim 34 , wherein the instructions sent to the user node comprise instructions to suspend the evaluation of the at least one execution condition for the released SCG until the user node executes at least one conditional PCell addition .37 . A method to be carried out by a user node , comprising : receiving, from a master node , at least one execution condition for a conditional primary secondary cell , PScell , addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change , SCPAC, condition for execution of CPA to be performed after a secondary cell group, SCG, release , wherein the at least one execution condition for CPA is configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change , CPC .38 . The method of claim 37 , wherein the at least one execution condition for CPA comprise at least one A4 event condition mapped to a master cell group, MCG, configuration, wherein the at least one A4 event condition is defined for candidate SCPAC configurations .39 . The method of claim 38 , wherein the at least one execution condition for CPA comprises one A4 event condition common for all candidate SCPAC configurations .40 . The method of claim 38 , wherein the at least one execution condition for CPA comprises A4 event conditions speci fic for each candidate SCPAC configuration .41 . The method of any of claims 37 to 40 , comprising : receiving, from the master node , a reconfiguration message for SCG release ; performing the SCG release , comprising : releasing SCG configuration; releasing measurement configuration of at least one of an initial CPC condition or a subsequent CPC condition;releasing at least one of the CPC condition or the subsequent CPC condition; evaluating the SCPAC condition based on the at least one execution condition for CPA; and after the SCG release , executing CPA based on the evaluating .42 . The method of claim 41 , comprising : receiving, from the master node , the at least one execution condition for CPA with an indication to deactivate the at least one execution condition for CPA for execution of CPA; storing the at least one execution condition in a deactivated state ; and receiving, from the master node , the reconfiguration message for the SCG release with an indication to activate the at least one execution condition for CPA for execution of CPA.43 . The method of claim 37 , wherein the at least one execution condition for CPA comprises instructions to maintain measurement configurations associated with the released SCG and SCPAC condition evaluation wherein the instructions instruct the user node to continue , after the SCG release , SCPAC condition evaluation based on the at least one of A3 event condition or A5 event condition of the CPC with measurement configurations associated with the released SCG .44 . The method of any of claims 37 to 43 , wherein the at least one execution condition for CPA is received in a radio resource control , RRC , reconfiguration message including at least one of an initial CPC condition configuration or a subsequent CPC condition configuration .45 . The method of any of claims 37 to 43 , wherein the at least one execution condition for CPA is received in a RRC reconfiguration message for the SCG release .46 . The method of any of claims 37 to 45 , comprising : receiving instructions from the master node to suspend evaluation of the at least one execution condition for CPA for the released SCG; and suspending the evaluation of the at least one execution condition for CPA for the released SCG according to the instructions .47 . The method of claim 46 , wherein the instructions received from the master node comprise instructions to suspend the evaluation of the at least one execution condition for CPA for the released SCG for a certain period of time from the SCG release .48 . The method of claim 46 , wherein the instructions received from the master node comprise instructions to suspend the evaluation of the at least one execution condition for CPA for the released SCG until the user node executes at least one conditional PCell addition .49 . The method of any of claims 43 to 48 , comprising : receiving, from the master node , a reconfiguration message for SCG release before an initial conditional PScell change has been executed; performing the SCG release , comprising : releasing SCG configuration; maintaining measurement configurations of initial CPC conditions and maintaining initial CPC conditions ; updating the initial CPC conditions for CPA, wherein the initial CPC conditions are evaluated for candidate SCPACconfigurations with released PScell measurements as serving PScell measurements ; and upon or after the SCG release , performing evaluation for the conditional PScell addition execution based on the update .50 . The method of any of claims 37 to 48 , comprising : receiving, from the master node , a reconfiguration message for SCG release after an initial conditional PScell change has been executed; performing the SCG release , comprising : maintaining SCG configuration, maintaining measurement configurations of subsequent conditional PScell change , CPC , conditions ; maintaining subsequent CPC conditions ; and updating the subsequent CPC conditions for CPA, wherein the subsequent CPC conditions are evaluated for candidate SCPAC configurations with released PScell measurements as serving PScell measurements ; and upon or after the SCG release , performing evaluation for the conditional PScell addition execution based on the update .51 . An apparatus comprising at least means for sending, to a user node , at least one execution condition for a conditional primary secondary cell , PScell , addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change , SCPAC, condition evaluation for execution of CPA to be performed after a secondary cell group, SCG, release , and wherein the at least one execution condition for CPA is configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change , CPC .52 . An apparatus comprising at least means for receiving, from a master node , at least one execution condition for a conditional primary secondary cell , PScell , addition, CPA, to be applied by the user node for evaluation of a subsequent conditional PScell addition or change , SCPAC, condition evaluation for execution of CPA to be performed after a secondary cell group, SCG, release , and wherein the at least one execution condition for CPA is configured to replace at least one execution condition configured to the user node for evaluation of the SCPAC condition for a conditional PScell change , CPC .53 . A computer readable medium comprising instructions which, when executed by an apparatus , cause the apparatus to perform at least the method of any of claims 26 to 36 .54 . A computer readable medium comprising instructions which, when executed by an apparatus cause the apparatus to perform at least the method of any of claims 37 to 50 .

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