A user equipment and a base station acting as a source cell for the user equipment

Abstract

A user equipment (UE) can be configured with information for performing a conditional handover or an addition / change of a primary secondary cell (PSCell). The UE receives, from a source cell, a first radio resource control (RRC) configuration message for a conditional handover to at least one target cell, the first RRC configuration message including a conditional handover execution condition, an RRC configuration, and a target cell ID for each of a list of target cells; performs measurements on the target cells to determine whether any of the target cells satisfies its corresponding conditional handover execution condition; and initiates a handover to a first target cell from the list of target cells when the first target cell satisfies its corresponding conditional handover execution condition.

Description

TECHNICAL FIELD

[0001] The present application relates generally to wireless communications, and in particular to target cell IDs for conditional handover and conditional PSCell addition or change. BACKGROUND

[0002] Conditional handover (CHO) involves an operation in which a network provides a user equipment (UE) with a list of target cells for CHO with corresponding radio resource control (RRC) configurations that are prepared for handover to the UE prior to actual handover. For each target cell, the source gNB provides at least one condition for the UE to perform CHO. The condition can involve a radio quality of the target cell as determined by the UE. The UE performs measurements on the target cells, and when the condition is met for a target cell, the UE initiates CHO and immediately applies the pre-configured target cell configuration. With CHO, the UE is able to perform handover without involving the source cell, e.g., even when the radio quality of the connection with the source cell has degraded such that a handover initiated by the source cell is not possible. Conditional primary secondary cell (PSCell) addition / change (CPAC) involves a similar operation in which a UE is provided with a list of target PSCells and corresponding conditions for handover, and when the condition is met for one of the target PSCells, the UE initiates handover.

[0003] For each target cell provided to the UE in either of the example operations (CHO or CPAC), the UE parses the RRC configuration to obtain the physical cell ID of the target cell. Given that the number of target cells provided can be high and that most of the target cells will not be used for handover, the processing burden associated with RRC configuration parsing can be high. SUMMARY

[0004] Some example embodiments relate to a user equipment (UE) having a transceiver configured to communicate with a source cell and at least one target cell, and a processor communicatively coupled to the transceiver and configured to perform operations. The operations include receiving, from the source cell, a first radio resource control (RRC) configuration message for conditional handover to the at least one target cell, the first RRC configuration message including a conditional handover execution condition, an RRC configuration, and a target cell ID for each of a list of target cells, performing measurements on the target cells to determine whether any of the target cells meets its corresponding conditional handover execution condition, and initiating handover to a first target cell from the list of target cells when the first target cell meets its corresponding conditional handover execution condition.

[0005] Other example embodiments relate to a processor of a user equipment (UE) configured to perform operations. The operations include receiving, from a source cell, a first radio resource control (RRC) configuration message for a conditional handover to at least one target cell, the first RRC configuration message including a conditional handover execution condition, an RRC configuration, and a target cell ID for each of a list of target cells; performing measurements on the target cells to determine whether any of the target cells satisfies its corresponding conditional handover execution condition; and initiating a handover to a first target cell from the list of target cells when the first target cell satisfies its corresponding conditional handover execution condition.

[0006] Still other example embodiments relate to a base station acting as a source cell of a user equipment (UE). The base station includes a transceiver configured to communicate with the UE and at least one target cell, and a processor communicatively coupled to the transceiver and configured to perform operations. The operations include sending a conditional handover request to the at least one target cell and receiving a conditional handover response including a radio resource control (RRC) configuration for the at least one target cell; transmitting, to the UE, a first RRC configuration message for a conditional handover, the first RRC configuration message including a conditional handover execution condition, the RRC configuration, and a target cell ID for each of a list of target cells, wherein the UE performs measurements on the target cells to determine whether any of the target cells satisfies its corresponding conditional handover execution condition; and the UE initiating a handover to a first target cell from the list of target cells when the first target cell satisfies its corresponding conditional handover execution condition. BRIEF DESCRIPTION OF DRAWINGS

[0007] Figure 1 An example network arrangement is shown in accordance with various example embodiments.

[0008] Figure 2 An example UE is shown in accordance with various example embodiments.

[0009] Figure 3 An example network cell is shown in accordance with various example embodiments.

[0010] Figure 4 A signaling diagram for conditional handover (CHO) is shown in accordance with various example embodiments.

[0011] Figure 5 A signaling diagram for conditional PSCell addition / change (CPAC) is shown in accordance with various example embodiments.

[0012] Figure 6Methods for CHO or CPAC are shown in accordance with various example embodiments.

[0013] Figure 7 CHO configuration information elements (IEs) are shown in accordance with various example embodiments.

[0014] Figure 8 CHO configuration information elements (IEs) are shown in accordance with various example embodiments. DETAILED DESCRIPTION

[0015] Example embodiments can be further understood with reference to the following description and related drawings in which like elements are referred to with the same reference numerals. The example embodiments relate to operations for performing conditional handover (CHO) or conditional primary secondary cell (PSCell) addition / change (CPAC) for a user equipment (UE). In example operations, the UE is provided with a target cell ID for each of the target cells in a source configuration received from a source cell for handover. The UE does not need to parse radio resource control (RRC) configuration data for the target cells, thereby reducing the UE processing burden. In some embodiments, a downlink (DL) frequency is also provided to the UE for each of the target cells.

[0016] Figure 1 An example network arrangement 100 is shown in accordance with various example embodiments. The example network arrangement 100 includes a plurality of UEs 110, 112. Those skilled in the art will appreciate that a UE can be any type of electronic component configured to communicate via a network, such as a component of a connected car, a mobile phone, a tablet computer, a smart phone, a phablet, an embedded device, a wearable device, an Internet of Things (IoT) device, etc. It will also be appreciated that a practical network arrangement can include any number of UEs used by any number of users. Thus, the example having two UEs 110, 112 is provided for illustrative purposes only. In some example embodiments described below, a group of UEs can be employed for corresponding channel measurements.

[0017] The UEs 110, 112 can communicate directly with one or more networks. In the example of network arrangement 100, the networks with which the UEs 110, 112 can wirelessly communicate are a 5G NR radio access network (5G NR-RAN) 120, a LTE radio access network (LTE-RAN) 122, and a wireless local area network (WLAN) 124. Thus, the UEs 110, 112 can include a 5G NR chipset to communicate with the 5G NR-RAN 120, an LTE chipset to communicate with the LTE-RAN 122, and an ISM chipset to communicate with the WLAN 124. However, the UEs 110, 112 can also communicate with other types of networks (e.g., a legacy cellular network), and the UE 110 can also communicate with a network through a wired connection. With reference to the example embodiment, the UEs 110, 112 can establish a connection with the 5G NR-RAN 120 and / or the LTE-RAN 122.

[0018] The 5G NR-RAN 120 and the LTE-RAN 122 can be part of a cellular network that can be deployed by a cellular provider (e.g., Verizon, AT&T, T-Mobile, etc.). These networks 120, 122 can include, for example, cells or base stations (NodeBs, eNodeBs, HeNBs, eNBS, gNBs, gNodeBs, macrocell base stations, microcell base stations, small cell base stations, femtocell base stations, etc.) configured to send and receive traffic from UEs equipped with the appropriate cellular chipset. The WLAN 124 can include any type of wireless local area network (WiFi, hotspots, IEEE 802.1 lx networks, etc.).

[0019] The UEs 110, 112 can connect to the 5G NR-RAN 120 via at least one of a next generation NodeB (gNB) 120A and / or a gNB 120B. The reference to two gNBs 120A, 120B is for illustrative purposes only. Example embodiments can apply to any appropriate number of gNBs. For example, the UEs 110, 112 can simultaneously connect and exchange data with multiple gNBs in a multi-cell CA configuration. The UEs 110, 112 can also connect to the LTE-RAN 122 via either or both of eNBs 122A, 122B, or to any other type of RAN, as described above. In the network arrangement 100, the UE 110 is shown as having a connection to the gNB 120A, while the UE 112 is shown as having a connection to the gNB 120B.

[0020] The example embodiments described herein relate to handover, in which a UE transitions from a connection on a first cell to a connection on a second cell. In some embodiments, the handover is performed between gNBs, such as a handover from gNB 120A to gNB 120B (inter-node handover), while in other embodiments, the handover is performed between co-located cells at a single gNB, such as gNB 120A (intra-node handover).

[0021] In addition to networks 120, 122, and 124, network arrangement 100 includes cellular core network 130, Internet 140, IP Multimedia Subsystem (IMS) 150, and network services backbone 160. Cellular core network 130 (e.g., 5GC of NR) can be viewed as an interconnected set of components that manage the operation and traffic of a cellular network. Cellular core network 130 also manages traffic that flows between the cellular network and Internet 140.

[0022] IMS 150 can generally be described as an architecture for delivering multimedia services to UEs 110 using IP protocols. IMS 150 can communicate with cellular core network 130 and Internet 140 to provide multimedia services to UEs 110. Network services backbone 160 communicates with Internet 140 and cellular core network 130, either directly or indirectly. Network services backbone 160 can generally be described as a set of components (e.g., servers, network storage arrangements, etc.) that implement a suite of services that can be used to extend the functionality of UEs 110 in communicating with various networks.

[0023] Figure 2 An example UE 110 according to various example embodiments is shown. UE 110 will be described with reference to network arrangement 100 of Figure 1 UE 110 can represent any electronic device and can include processor 205, memory arrangement 210, display device 215, input / output (I / O) device 220, transceiver 225, and other components 230. Other components 230 can include, for example, an audio input device, an audio output device, a battery providing a limited power source, a data acquisition device, a port for electrically connecting UE 110 to other electronic devices, a sensor for detecting a condition of UE 110, etc. Figure 2 The UE 110 shown can also represent UE 112.

[0024] The processor 205 can be configured to execute a number of engines of the UE 110. For example, the engines can include a conditional handover (CHO) engine 235 for performing operations including receiving a CHO command from a network cell and initiating a handover when a radio quality condition for a target cell is met. The operations can also include determining a physical cell ID for one or more target cells based on a radio resource control (RRC) configuration message received from a network cell, as described in detail below.

[0025] The engines described above are exemplary only as applications (e.g., programs) executed by the processor 205. The functionality associated with the engines can also be represented as separate integrated components of the UE 110 or can be modular components coupled to the UE 110, e.g., integrated circuits with or without firmware. For example, the integrated circuits can include input circuitry for receiving signals and processing circuitry for processing the signals and other information. The engines can also be embodied as one application or as multiple applications separate from one another. Moreover, in some UEs, the functionality described for the processor 205 is split between two or more processors, such as a baseband processor and an application processor. The exemplary embodiments can be implemented in any of these or other configurations of the UE.

[0026] The memory 210 can be a hardware component configured to store data related to operations performed by the UE 110. The display device 215 can be a hardware component configured to display data to a user, while the I / O device 220 can be a hardware component that enables input by a user. The display device 215 and the I / O device 220 can be separate components or can be integrated together, such as a touch screen. The transceiver 225 can be a hardware component configured to establish a connection with the 5G-NR RAN 120, the LTE RAN 122, etc. Accordingly, the transceiver 225 can operate on various different frequencies or channels (e.g., contiguous sets of frequencies).

[0027] Figure 3 An exemplary network cell, in this case a gNB 120A, is shown in accordance with various exemplary embodiments. As described above with reference to the UE 110, the gNB 120A can represent a cell that provides service as a PCell or SCell or is configured independently with the UE 110. The gNB 120A can represent any access node of a 5G NR network through which the UEs 110, 112 can establish a connection and manage network operations. Figure 3 The gNB 120A shown can also represent the gNB 120B.

[0028] The gNB 120A can include a processor 305, memory arrangement 310, input / output (I / O) devices 320, transceiver 325, and other components 330. The other components 330 can include, for example, an audio input device, an audio output device, a battery, a data acquisition device, a port for electrically connecting the gNB 120A to other electronic devices, etc.

[0029] The processor 305 can be configured to execute a number of engines of the gNB 120A. For example, the engines can include a conditional handover (CHO) engine 335 for performing operations including transmitting a CHO command to a UE so that the UE initiates a handover when a radio quality condition of a target cell, as determined by the UE, is satisfied. The operations can also include indicating a physical cell ID for one or more target cells in a radio resource control (RRC) configuration message transmitted to the UE, as described in detail below.

[0030] The engines described above are each exemplary of an application (e.g., a program) executed by the processor 305. The functionality associated with the engines can also be represented as integral components of the gNB 120A, or can be modular components coupled to the gNB 120A, e.g., integrated circuits with or without firmware. For example, the integrated circuits can include input circuitry for receiving signals and processing circuitry for processing signals and other information. Further, in some gNBs, the functionality described with respect to the processor 305 is split among multiple processors (e.g., a baseband processor, an application processor, etc.). The exemplary embodiments can be implemented in accordance with any of these or other configurations of the gNB.

[0031] The memory 310 can be a hardware component configured to store data related to operations performed by the UE 110, 112. The I / O devices 320 can be hardware components or ports that enable a user to interact with the gNB 120A. The transceiver 325 can be a hardware component configured to exchange data with the UE 110, 112 and any other UE in the system 100. The transceiver 325 can operate on various different frequencies or channels (e.g., a set of contiguous frequencies). Thus, the transceiver 325 can include one or more components (e.g., radio components) to enable data exchange with various networks and UEs.

[0032] Conditional handover (CHO) was introduced in Rel-16 to improve handover (HO) reliability. CHO operation includes the network providing a list of target cells for CHO with corresponding RRC configuration, which is prepared for handover to the UE before actual handover. For each target cell, the source gNB provides a condition for the UE to execute CHO. The condition can involve a radio quality of the target cell as determined by the UE. The UE performs measurements on the target cells and when the condition is met for a target cell, the UE starts CHO and immediately applies the pre-configured target cell configuration. With CHO, the UE is able to perform handover without involving the source cell, e.g., even when the radio quality of the connection to the source cell has degraded such that a handover initiated by the source cell is not possible.

[0033] Figure 4 A signaling diagram 400 is shown for conditional handover (CHO). The signaling diagram 400 relates to existing specifications for CHO. In the example signaling diagram 400, two target cells (a first target cell (T-gNB 1) and a second target cell (T-gNB 2) are shown as potential HO candidates for the UE. However, any number of target cells can be configured as potential HO candidates. The signaling diagram 400 also includes a source cell (S-gNB) that initiates the CHO operation.

[0034] In 405, the source gNB prepares one or more target gNBs for conditional handover (CHO). The target gNB preparation can include the source gNB sending a CHO request to the one or more target gNBs and receiving a CHO response (e.g., HO request acknowledgement) that includes configuration for a CHO candidate cell. A CHO response can be sent for each candidate cell, including configuration data for that candidate cell.

[0035] In 410, the source gNB sends an RRCReconfiguration message to the UE that includes CHO configuration for each of the target cells prepared by the source gNB. The CHO configuration can include CHO execution conditions, which can include one or more trigger conditions for a CHO event, such as a reference signal received power (RSRP), a reference signal received quality (RSRQ), or a signal to interference plus noise ratio (SINR) quantity for evaluating the quality of a radio link.

[0036] In 415, upon receiving the RRCReconfiguration message, the UE decodes the source configuration and CHO conditions and stores the CHO RRC configuration for each target cell. When the UE has successfully processed the CHO RRC configuration, the UE sends an RRCReconfigurationComplete message to the source gNB. The UE processing can include parsing each of these CHO RRC configurations to extract the physical cell ID for each of the target cells.

[0037] In 420, the UE performs measurements on the target cells for determining whether the target cells satisfy the CHO conditions for the cells. In the example signaling diagram 400, the UE determines that the CHO condition is satisfied for the second target gNB.

[0038] In 425, the UE performs a handover for the target cell that has satisfied the CHO condition (i.e., the second target cell). The handover operation includes a random access (RACH) procedure with the second target cell, and when the CHO is complete, the UE sends an RRCReconfigurationComplete message to the second target cell.

[0039] 430 illustrates an alternative procedure when the RACH procedure with the handover target cell fails (e.g., handover failure (HOF) or radio link failure (RLF) handling). In this scenario, the UE performs cell selection and determines a suitable cell for CHO. If no suitable cell is found for CHO, the UE selects to another cell and performs a traditional RRC re-establishment.

[0040] In conditional PSCell addition / change (CPAC), the UE performs similar operations as described above for CHO. In CPAC, a secondary node (SN) can provide a list of target cells for conditional PSCell change, which is prepared for PSCell change for the UE. For each target cell, the SN provides a condition for the UE to perform PSCell change. The UE performs measurements on the target cells and when the condition is satisfied, the UE initiates PSCell change and immediately applies the target cell configuration.

[0041] Figure 5A signaling diagram 500 is shown for conditional PSCell addition / change (CPAC). The signaling diagram 500 relates to existing specifications for CPAC and includes two options to be discussed below. The first option relates to a master node (MN) that implements PSCell change, while the second option relates to intra-SN CPAC and does not include a MN. In the example signaling diagram 500, one target cell (target PSCell (T-PSCell)) is shown as a potential CPAC candidate on a secondary node (SN) of the UE. However, any number of target cells can be configured as potential CPAC candidates.

[0042] For the first option, in 505, a secondary node (SN) of the UE sends an RRCReconfiguration message for a secondary cell group (SCG) to a master node (MN) of the UE. The RRCReconfiguration message can include a list with configurations of CPAC candidate cells for CHO.

[0043] In 510, the MN sends an RRCReconfiguration message to the UE including CHO configurations for each of the target PSCells. Similar to the method 400, the CHO configuration for each target PSCell includes a CHO configuration ID, a CHO execution condition (measurement ID), and a CHO RRC configuration (target cell configuration). The CHO execution condition can include one or more trigger conditions for a CHO event, such as RSRP, RSRQ, or SINR quantities for evaluating the quality of a radio link.

[0044] In 515, upon receiving the RRCReconfiguration message, the UE decodes the source configuration and CHO conditions and stores the CHO RRC configuration for each target PSCell. When the UE has successfully processed the CHO RRC configuration, the UE sends an RRCReconfigurationComplete message to the MN. In 520, the MN informs the SN of the successful RRCReconfiguration of the UE.

[0045] In 525, the UE performs measurements on the target PSCells for determining whether the target PSCells satisfy the CHO conditions for the cells. In the example signaling diagram 500, the UE determines that the CHO condition is satisfied for the T-PSCell.

[0046] In 530, the UE performs handover for the PSCell (e.g., T-PSCell) for which the CHO condition has been met. When the CHO is completed, the UE sends an RRCReconfigurationComplete message to the MN. In 535, the MN informs the PSCell of the successful CPAC operation.

[0047] For the second option, in 540, the SN sends the UE an RRCReconfiguration message including CHO configuration for each of the target PSCells. Similar to method 400, the CHO configuration for each target PSCell includes a CHO configuration ID, a CHO execution condition (measurement ID), and a CHO RRC configuration (target cell configuration). The CHO execution condition can include one or more trigger conditions for a CHO event, such as RSRP, RSRP, or SINR quantities for evaluating the quality of a radio link.

[0048] In 545, upon receiving the RRCReconfiguration message, the UE decodes the source configuration and the CHO condition, and stores the CHO RRC configuration for each target PSCell. In 550, the UE performs measurements on the target PSCells for determining whether the target PSCell meets the CHO condition for that cell. In the example signaling diagram 500, the UE determines that the CHO condition is met for the T-PSCell.

[0049] In 555, the UE performs handover for the PSCell (i.e., T-PSCell) for which the CHO condition has been met. When the CHO is completed, the UE sends an RRCReconfigurationComplete message to the T-PSCell.

[0050] Figure 6 A method 600 for CHO or CPAC is shown in accordance with various example embodiments. The method 600 can be applied to any of the conditional handover scenarios described above (CHO or CPAC).

[0051] In 605, the UE receives a CHO configuration for a list of target cells from a source cell. According to various example embodiments, the CHO configuration received by the UE from the source cell in 605 includes an identification of the target cells. As noted above, the current procedure requires the UE to parse the RRCReconfiguration message to extract the physical cell ID for each of the target cells. In example embodiments, the physical cell ID of the target cells is included in the CHO configuration, thereby eliminating the need for the UE to parse the RRCReconfiguration message. Various examples of including the physical cell ID of the target cells in the CHO configuration are described below.

[0052] According to some example embodiments, the CHO configuration for the target cells (provided by the source cell to the UE) includes a target cell ID for each of the target cells. Figure 7 A CHO configuration information element (IE) 700 according to various example embodiments described herein is shown. In this example, there are two cells on the list. Thus, Figure 7 The CHO configuration IE 700 includes a CHO configuration ID, a CHO condition (measurement ID), a CHO RRC configuration, and a target cell ID for each of the two cells on the list. Figure 7

[0053] In these embodiments, the UE can determine the target physical cell ID (PhysCellID) directly from reading the source configuration without the need to parse the target cell RRCreconfiguration. When the UE performs the target cell check, the UE uses the PhysCellId along with the frequency indicated by the measurement object (e.g., MeasID) to identify whether the cell being checked is the one indicated by the target RRCReconfiguration. Thus, the UE does not need to parse the target cell RRCReconfiguration.

[0054] According to other example embodiments, the CHO configuration for the target cells can include a target cell ID and a downlink (DL) frequency (ssbFrequency) for each of the target cells. Figure 8 A CHO configuration information element (IE) 800 according to various example embodiments described herein is shown. In this example, there are two cells on the list. Thus, Figure 8 The CHO configuration IE 800 includes a CHO configuration ID, a CHO condition (measurement ID), a CHO RRC configuration, and a target cell ID for each of the two cells on the list. Figure 8 ​The CHO configuration IE 800 includes the CHO configuration ID, CHO condition, CHO RRC configuration, target cell ID, and DL frequency for two cells in the list.

[0055] In these embodiments, the UE can determine the target physical cell ID and DL frequency directly from the read source configuration without the need to parse the target cell RRCreconfiguration (similar to the embodiments discussed above) or the CHO condition (measurement ID). When the UE performs the target cell check, the UE can use the PhysCellId along with the frequency (indicated by ssbFrequency) to identify whether the cell being checked is the one indicated by the target RRCReconfiguration.

[0056] In some example embodiments, the CHO configuration for the target cells (provided by the source cell to the UE) can include the target cell ID and DL frequency for each of the target cells in the CHO configuration IE. The CHO configuration IE corresponds to the CHO condition discussed above.

[0057] In this embodiment, the UE can determine the target physical cell ID (PhysCellID) and DL frequency from the MeasObject IE without the need to parse the target cell RRCreconfiguration. If multiple CHO cells are configured in the measurement object, the rule of mapping the cell ID in this configuration to the cell index in the CondReconfigToAddModList can be implemented.

[0058] In 610, the UE performs radio resource management (RRM) measurements on the received list of cells. After performing the measurements for the target cell IDs of the target cell list, the UE evaluates the channel quality of the target cells. In 615, when a target cell satisfies its CHO condition, the UE applies the RRCReconfig for that cell.

[0059] Those skilled in the art will appreciate that the exemplary embodiments described above can be implemented in any suitable software configuration or hardware configuration, or a combination thereof. Exemplary hardware platforms for implementing the exemplary embodiments can include, for example, Intel x86-based platforms with compatible operating systems, Windows OS, Mac platforms and MAC OS, mobile devices with operating systems such as iOS, Android, and the like. In other examples, exemplary embodiments of the above-described methods can be embodied as programs including code lines stored on a non-transitory computer-readable storage medium, which, when compiled, can be executed on a processor or microprocessor.

[0060] While this patent application describes various combinations of various embodiments each having different features, those skilled in the art will appreciate that any feature of one embodiment can be combined with features of other embodiments or features that are not inconsistent with the operation or functioning of the devices of the disclosed embodiments or that do not render said functionality inconsistent, in any manner not expressly disclosed, without departing from the spirit or scope of the disclosure.

[0061] It is well understood that the use of personally identifiable information should follow privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled in a way that minimizes risks to the privacy of the users, and that is consistent with the principles underlying applicable laws and regulations.

[0062] Various modifications to the disclosure will be apparent to those skilled in the art, and the disclosure is intended to cover any and all such modifications, provided they come within the scope of the claims or equivalents thereof. Accordingly, although specific embodiments have been described, these are examples only and are not limiting upon the scope of the present disclosure.

Claims

1. A user equipment (UE) comprising: a transceiver configured to communicate with a source cell and at least one target cell; and a processor communicatively coupled to the transceiver and configured to perform operations comprising: receiving, from the source cell, a first radio resource control (RRC) configuration message for a conditional handover, the first RRC configuration message including a conditional handover information element (IE), the conditional handover IE including, for each of a list of target cells, a conditional handover execution condition, a conditional handover RRC configuration, and a target cell ID, wherein the conditional handover is an intra-node handover performed between co-located cells of a single next generation Node B (gNB), wherein the UE receives the target cell ID for each of the target cells directly from the conditional handover IE and does not parse an RRCReconfiguration message for each of the target cells to determine the corresponding target cell ID; performing measurements on the target cells to determine whether any of the target cells satisfy its corresponding conditional handover execution condition; and initiating a handover to a first target cell from the list of target cells when the first target cell satisfies its corresponding conditional handover execution condition.

2. The UE of claim 1, wherein the conditional handover IE further includes a downlink frequency in a measurement object for each of the target cells.

3. The UE of claim 1, wherein the UE receives the downlink frequency for each of the target cells directly from the conditional handover IE and does not parse a measurement object for each of the target cells to determine the corresponding downlink frequency.

4. The UE of claim 1, wherein the conditional handover IE further includes a downlink frequency in a measurement object and the target cell ID for each of the target cells, and the UE does not parse the RRCReconfiguration message for each of the target cells to determine the corresponding target cell ID.

5. The UE of claim 4, wherein the operations further comprise: when multiple target cells are configured in a single measurement object, mapping cell IDs from the single measurement object to a list of cell indices to determine the corresponding target cell ID.

6. A processor of a user equipment (UE) configured to perform operations comprising: receiving, from a source cell, a first radio resource control (RRC) configuration message for a conditional handover, the first RRC configuration message including a conditional handover information element (IE), the conditional handover IE including a conditional handover execution condition, a conditional handover RRC configuration, and a target cell ID for each of a list of target cells, wherein the conditional handover is an intra-node handover performed between co-located cells of a single next generation Node B (gNB), wherein the target cell ID for each of the target cells is received directly from the conditional handover IE, and the processor does not parse an RRCReconfiguration message for each of the target cells to determine the corresponding target cell ID; performing measurements on the target cells to determine whether any of the target cells satisfy its corresponding conditional handover execution condition; and initiating a handover to a first target cell from the list of target cells when the first target cell satisfies its corresponding conditional handover execution condition.

7. The processor of claim 6, wherein the conditional handover IE further includes a downlink frequency in a measurement object for each of the target cells.

8. The processor of claim 6, wherein the downlink frequency for each of the target cells is received directly from the conditional handover IE, and the processor does not parse a measurement object for each of the target cells to determine the corresponding downlink frequency.

9. The processor of claim 6, wherein the conditional handover IE further includes a downlink frequency in a measurement object and the target cell ID for each of the target cells, and the processor does not parse the RRCReconfiguration message for each of the target cells to determine the corresponding target cell ID.

10. The processor of claim 9, wherein the operations further comprise: when multiple target cells are configured in a single measurement object, mapping cell IDs from the single measurement object to a list of cell indices to determine the corresponding target cell ID.

11. A base station serving as a source cell for a user equipment (UE), the base station comprising: a transceiver configured to communicate with the UE and at least one target cell; and a processor communicatively coupled to the transceiver and configured to perform operations comprising: sending a conditional handover request to the at least one target cell, and receiving a conditional handover response including a radio resource control (RRC) configuration for the at least one target cell, wherein conditional handover is an intra-node handover performed between co-located cells of a single next generation Node B (gNB); transmitting, to the UE, a first RRC configuration message for conditional handover, the first RRC configuration message including a conditional handover IE, the conditional handover IE including, for each of a list of target cells, a conditional handover execution condition, the RRC configuration, and a target cell ID, wherein the target cell ID for each of the target cells is included directly in the conditional handover IE such that the UE does not parse an RRCReconfiguration message for each of the target cells to determine a corresponding target cell ID, wherein the UE performs measurements on the target cells to determine whether any of the target cells satisfy their corresponding conditional handover execution condition, and the UE initiates a handover to a first target cell from the list of target cells when the first target cell satisfies its corresponding conditional handover execution condition.

12. The base station of claim 11, wherein the conditional handover IE further includes a downlink frequency in a measurement object for each of the target cells.

13. The base station of claim 11, wherein the downlink frequency for each of the target cells is included directly in the conditional handover IE such that the UE does not parse a measurement object for each of the target cells to determine a corresponding downlink frequency.

14. The base station of claim 11, wherein the conditional handover IE further includes the downlink frequency and the target cell ID in a measurement object for each of the target cells such that the UE does not parse the RRCReconfiguration message for each of the target cells to determine a corresponding target cell ID.

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