Layer 3 measurement reporting

Abstract

Example embodiments of the present disclosure relate to transmission of Layer 3 (L3) measurement reports. In one aspect, a terminal device receives a cell activation command for activating a first cell from a network device. The terminal device determines whether at least one condition for reporting the L3 measurement report is satisfied. Based on determining that the at least one condition is satisfied, the terminal device transmits, to the network device, an L3 measurement report including at least one valid measurement result for a second cell, where the second cell is different from the first cell. In this way, the activation time delay of cell activation is reduced.

Description

[0001] field

[0002] The exemplary embodiments of this disclosure generally relate to the field of communications, and in particular to devices, methods, apparatuses, and computer-readable storage media for transmitting Layer 3 (L3) measurement reports. Background Technology

[0003] In communications technology, there is continuous evolution in order to provide efficient and reliable solutions utilizing wireless communication networks. Each generation presents its own technological challenges, addressing the different situations and processes required to connect and serve devices connected to wireless networks. To meet the ever-increasing demand for wireless data traffic since the deployment of 4G communication systems, efforts have been made to develop improved 5G, pre-5G, 6G, or higher communication systems.

[0004] In New Radio (NR)—as in Long Term Evolution (LTE)—cells can be activated or deactivated. The transition between activated and deactivated states is primarily based on Media Access Control (MAC) control element (CE) commands from the network, such as cell activation / deactivation commands. When a User Equipment (UE) activates a deactivated cell, there is a time delay required to transition from the deactivated state to the activated state. Radio Access Network Working Group 4 (RAN4) in the 3GPP (3rd Generation Partnership Project) defines a delay requirement within which the UE should be able to activate a deactivated cell no later than one time period after receiving a cell activation command in time slot n. Summary of the Invention

[0005] In general, the exemplary embodiments of this disclosure provide solutions for transmitting Layer 3 (L3) measurement reports, for example, to reduce activation latency of cell activation.

[0006] In a first aspect, a terminal device is provided. The terminal device includes at least one processor and at least one memory storing instructions, which, when executed by the at least one processor, cause the terminal device to at least: receive from a network device a cell activation command for activating a first cell; determine whether at least one condition for reporting a Layer 3 (L3) measurement report is met; and based on the determination that the at least one condition is met, transmit to the network device an L3 measurement report including at least one valid measurement result of a second cell, wherein the second cell is different from the first cell.

[0007] In a second aspect, a network device is provided. The network device includes at least one processor and at least one memory storing instructions, which, when executed by the at least one processor, cause the network device to at least: transmit a cell activation command to a terminal device for activating a first cell; receive a Layer 3 (L3) measurement report from the terminal device including at least one valid measurement result of a second cell; and transmit a Transmission Configuration Indicator (TCI) activation command to the terminal device indicating a TCI state associated with the first cell determined based on the L3 measurement report.

[0008] In a third aspect, a method is provided. The method includes: receiving from a network device a cell activation command for activating a first cell; determining whether at least one condition for reporting a Layer 3 (L3) measurement report is met; and based on the determination that the at least one condition is met, transmitting to the network device an L3 measurement report including at least one valid measurement result of a second cell.

[0009] In a fourth aspect, a method is provided. The method includes: transmitting to a terminal device a cell activation command for activating a first cell; receiving from the terminal device a Layer 3 (L3) measurement report including at least one valid measurement result of a second cell, wherein the second cell is different from the first cell; and transmitting to the terminal device a Transmission Configuration Indicator (TCI) activation command indicating a TCI state associated with the first cell determined based on the L3 measurement report.

[0010] In a fifth aspect, an apparatus is provided. The apparatus includes: means for receiving from a network device a cell activation command for activating a first cell; means for determining whether at least one condition for reporting a Layer 3 (L3) measurement report is met; and means for transmitting, based on the determination that the at least one condition is met, an L3 measurement report including at least one valid measurement result of a second cell to the network device, wherein the second cell is different from the first cell.

[0011] In a sixth aspect, an apparatus is provided. The apparatus includes: means for transmitting to a terminal device a cell activation command for activating a first cell; means for receiving from the terminal device a Layer 3 (L3) measurement report including at least one valid measurement result of a second cell; and means for transmitting to the terminal device a Transmission Configuration Indicator (TCI) activation command indicating a TCI state associated with the first cell determined based on the L3 measurement report.

[0012] In a seventh aspect, a non-transitory computer-readable medium is provided, including program instructions for causing a device to perform a method according to at least any one of the third to fourth aspects.

[0013] In an eighth aspect, a computer program is provided, including instructions that, when executed by a device, cause the device to perform at least the method according to any one of the third to fourth aspects.

[0014] In a ninth aspect, a terminal device is provided. The terminal device includes: determining circuitry configured to receive from a network device a cell activation command for activating at least a first cell; determining circuitry configured to determine whether at least one condition for reporting a Layer 3 (L3) measurement report is met; and transmission circuitry configured to transmit, based on the determination that the at least one condition is met, an L3 measurement report including at least one valid measurement result of a second cell, wherein the second cell is different from the first cell.

[0015] In a tenth aspect, a network device is provided. The network device includes: a transmission circuit configured to transmit to a terminal device a cell activation command for activating a first cell; a receiving circuit configured to receive from the terminal device a Layer 3 (L3) measurement report including at least one valid measurement result of a second cell; and a transmission circuit configured to transmit to the terminal device a Transmission Configuration Indicator (TCI) activation command indicating a TCI state associated with the first cell determined based on the L3 measurement report.

[0016] It should be understood that the summary section is not intended to identify key or essential features of the embodiments of this disclosure, nor is it intended to limit the scope of this disclosure. Other features of this disclosure will become apparent from the following description. Attached Figure Description

[0017] Some exemplary embodiments will now be described with reference to the accompanying drawings, in which: Figure 1A Examples of network environments in which exemplary embodiments of this disclosure may be implemented are shown; Figure 1B The measurement reporting process is illustrated in connection with some embodiments of this disclosure; Figure 2 A flowchart of a method according to some embodiments of the present disclosure is shown; Figure 3 Several examples of L3 report transmissions according to some embodiments of this disclosure are shown; Figure 4 A flowchart is shown illustrating a method implemented at a terminal device according to some example embodiments of the present disclosure; Figure 5 A flowchart is shown of a method 500 implemented at a network device according to some example embodiments of the present disclosure; Figure 6A simplified block diagram of a device 600 suitable for implementing some example embodiments of the present disclosure is shown; and Figure 7 A block diagram illustrating an example of a computer-readable medium 700 according to some exemplary embodiments of the present disclosure is shown.

[0018] In all the accompanying drawings, the same or similar reference numerals denote the same or similar elements. Detailed Implementation

[0019] The principles of this disclosure will now be described with reference to some exemplary embodiments. It should be understood that these embodiments are described for illustrative purposes only and to assist those skilled in the art in understanding and implementing this disclosure, and do not imply any limitation on the scope of this disclosure. The disclosure described herein can be implemented in various ways other than those described below.

[0020] In the following description and claims, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0021] References to "an embodiment," "an embodiment," "an exemplary embodiment," etc., in this disclosure indicate that the described embodiment may include a particular feature, structure, or characteristic, but not every embodiment must include that particular feature, structure, or characteristic. Furthermore, these phrases do not necessarily refer to the same embodiment. Additionally, when a particular feature, structure, or characteristic is described in connection with an embodiment, it should be noted that those skilled in the art will recognize how such a feature, structure, or characteristic can be implemented in other embodiments, whether explicitly described or not.

[0022] It should be understood that although the terms "first" and "second," etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element, without departing from the scope of the exemplary embodiments. As used herein, the term "and / or" includes any and all combinations of one or more of the listed terms.

[0023] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that when the terms "comprising," "including," "having," "owning," "comprise," and / or "including" are used herein, they specify the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. As used herein, "at least one of the following: " and "at least one of " and similar wording, wherein the list of two or more elements is connected by "and" or "or," means at least any one element, or at least any two or more elements, or at least all elements.

[0024] As used in this application, the term "circuit" may refer to one or more or all of the following: (a) Hardware circuits only (such as in analog and / or digital circuits); and (b) A combination of hardware circuitry and software, such as (if applicable): (i) A combination of analog and / or digital hardware circuitry and software (e.g., firmware); and (ii) Any part of the hardware processor and software (including digital signal processors), software and memory, that works together to enable a device (such as a mobile phone or server) to perform various functions; and (c) Hardware circuitry and / or processors that require software (e.g., firmware) to function, such as a microprocessor or a portion thereof, but which may not exist when the software is not required to function.

[0025] This definition of "circuit" applies to all uses of the term in this application, including its use in any claim. As a further example, as used in this application, the term "circuit" also covers implementations of hardware circuitry or processors (or processors in general) or a portion thereof and their accompanying software and / or firmware. For example, if applicable to a particular claim element, the term "circuit" also covers baseband integrated circuits or processor integrated circuits in mobile devices, or similar integrated circuits in servers, cellular network devices, or other computing or networking devices.

[0026] As used herein, the term "cellular network" refers to a network operating according to any suitable radio access technology as defined by standards, such as Long Term Evolution (LTE), LTE-A Advanced (LTE-A), New Wideband Code Division Multiple Access (WCDMA), High-Speed ​​Packet Access (HSPA), Narrowband Internet of Things (NB-IoT), etc. Furthermore, communication between terminal devices and network devices in a cellular network can be performed according to any suitable communication protocol, including but not limited to fourth-generation (4G), 4.5G, future fifth-generation (5G) communication protocols, and / or any other currently known or future-developed protocols. Embodiments of this disclosure can be applied to various cellular networks. Given the rapid development of communications, there will naturally be future types of communication technologies and systems in which this disclosure can be embodied. It should not be construed as limiting the scope of this disclosure to the systems described above.

[0027] As used herein, the term "network device" refers to any device in a cellular network through which terminal devices access data networks and receive services exposed by other network devices in the cellular network. In some examples, a network device may include or implement the network functions of a 5G communication system (5GS) (e.g., the core network) of the cellular network. In some examples, a network device may be located in the RAN of the 5GS. A network device may be part of a satellite, base station (BS), or access point (AP), and may be, for example, a Node B (NodeB or NB), an evolved Node B (eNodeB or eNB), an NR NB (also known as a gNB), a Remote Radio Unit (RRU), a Radio Head (RH), a Remote Radio Head (RRH), a relay, a low-power node such as a femtonode, a piconode, etc., depending on the terminology and technology applied. A gNB may include a centralized unit (CU) and one or more distributed units (DUs). Femtonodes and piconodes are small base stations with small coverage areas.

[0028] The term "terminal equipment" refers to equipment in a cellular network communication system (such as a 5th generation communication system (5GS)) that may be capable of wireless (e.g., radio) communication with the 5GS's NR-RAN. As an example and not a limitation, terminal equipment may also be referred to as wireless communication equipment, user equipment (UE), user station (SS), portable user station, mobile station (MS), or access terminal (AT). Examples of terminal devices include, but are not limited to, mobile phones, cellular phones, smartphones, Voice over IP (VoIP) phones, wireless local loop phones, tablets, wearable terminal devices, personal digital assistants (PDAs), portable computers, desktop computers, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback devices, in-vehicle wireless terminal devices, wireless endpoints, mobile stations, laptop embedded devices (LEEs), laptop installed devices (LMEs), USB dongles, smart devices, wireless client devices (CPEs), Internet of Things (IoT) devices, watches or other wearable devices, head-mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in industrial and / or automated processing chain environments), consumer electronics devices, devices operating on commercial and / or industrial wireless networks, etc. In the following description, the terms "terminal device," "communication device," "terminal," "user equipment," and "UE" are used interchangeably.

[0029] In NR, when configuring a secondary cell (SCell) to be activated via the SCell activation command and triggering an L3 report, the UE may not have valid results for that SCell, while valid measurement results for other SCells may be available. Since the UE evaluates the validity of available measurement results when receiving the SCell activation command, the L3 report (if triggered) will be ready when the SCell activation command is received.

[0030] In view of the above, exemplary embodiments of this disclosure provide a solution for transmitting Layer 3 (L3) measurement reports, for example, to reduce activation latency for cell activation. In exemplary embodiments of this disclosure, a terminal device can receive a cell activation command from a network device for activating a first cell. The terminal device can then determine whether at least one condition for reporting a Layer 3 (L3) measurement report is met. Based on the determination that at least one condition is met, the terminal device can transmit an L3 measurement report to the network device including at least one valid measurement result of a second cell, wherein the second cell is different from the first cell. In this way, activation latency for cell activation is reduced.

[0031] Figure 1AAn example of a network environment 100a is shown, in which exemplary embodiments of this disclosure can be implemented. Environment 100a may be part of a communication network and includes multiple terminal devices and network devices, such as terminal device 110 and network device 120. As an example, terminal device 110 may be implemented as a user equipment (UE) or an access terminal (AT), and network device 120 may be implemented as an eNB or a base station (BS). Network device 120 can transmit various data to terminal device 110 through network environment 100.

[0032] To transmit data and / or control information, terminal device 110 can communicate with network device 120. The link from network device 120 to terminal device 110 is called a downlink (DL), while the link from terminal device 110 to network device 120 is called an uplink (UL).

[0033] Despite Figure 1A The communication environment 100 describes terminal device 110 and network device 120, but the embodiments of this disclosure can be equally applied to any other suitable communication devices communicating with each other. That is, the embodiments of this disclosure are not limited to... Figure 1A Example scenarios. In this regard, it should be noted that although the terminal device is schematically depicted as a mobile phone in FIG. 1 and the network device 120 is schematically depicted as a satellite in FIG. 1, it should be understood that these depictions are exemplary in nature and are not limiting in any way. In other embodiments, the terminal device 110 and the network device 120 may be any other communication device, such as any other wireless communication device.

[0034] It should be understood that Figure 1A The specific numbers of various communication devices and communication links shown are for illustrative purposes only and do not imply any limitation. Communication environment 100a may include any suitable number of communication devices and any suitable number of communication links for implementing embodiments of this disclosure. Furthermore, it should be understood that various wireless and wired communications may exist between all communication devices (if desired).

[0035] Figure 1B A measurement reporting process 100b related to some embodiments of this disclosure is illustrated. This process can be initiated after successful AS security activation. The terminal device 110 can then transmit the measurement report to the network device 120.

[0036] Terminal device 110 can set measId as the measurement identifier that triggers the measurement report. For each serving cell configured with servingCellMO, if the reportConfig associated with the measId that triggers the measurement report includes rsType, and if the serving cell measurement is available based on the rsType contained in the reportConfig that triggers the measurement report, then terminal device 110 can set measResultServingCell in measResultServingMOList to include RSRP, RSRO, and the available SINR of the serving cell, which are derived based on the rsType contained in the reportConfig that triggers the measurement report.

[0037] Figure 2 A flowchart of a method according to some embodiments of the present disclosure is shown. For purposes of discussion, method 200 will be referred to Figure 1A A description is provided. It should be understood that although process flow 200 has been referenced... Figure 1A While described, this process flow 200 can also be applied to other similar communication scenarios.

[0038] In process flow 200, network device 120 may transmit (205) a cell activation command 202 for activating a first cell to terminal device 110. Then, terminal device 110 may receive (210) the cell activation command 202 from network device 120.

[0039] Then, terminal device 110 can determine (220) whether at least one condition (i.e., one or more conditions) for reporting a Layer 3 (L3) measurement report is met. In some embodiments, when a valid measurement result of the first cell is unavailable, terminal device 110 can determine whether at least one condition for reporting a Layer 3 (L3) measurement report is met.

[0040] One or more conditions may include the availability of valid measurement results for at least one serving cell of terminal device 110. Alternatively, one or more conditions may include the availability of valid measurement results for at least one inactive cell (i.e., deactivated cell) of terminal device 110, and the at least one inactive cell includes a second cell. Alternatively, one or more conditions may include a first cell on frequency range 2 (FR2) band, and the availability of valid measurement results for a serving cell of terminal device 110 on the same FR2 band. Alternatively, one or more conditions may include a first cell on FR1 band, the availability of valid measurement results for a serving cell of terminal device 110, and the serving cell being on the (same) FR1 band and contiguous with the first cell. Alternatively, one or more conditions may include a first cell on frequency range 2 (FR2) band, and the availability of valid measurement results for an inactive cell of terminal device 110 on the same FR2 band. Additionally or alternatively, one or more conditions may include the first cell being on the FR1 band, valid measurement results of the inactive cell of the terminal device 110 being available, and the inactive cell being on the (same) FR1 band and contiguous with the first cell. In some embodiments, one or more conditions may include any combination of two or more of the items above.

[0041] Based on the determination that at least one condition is met, terminal device 110 may transmit (225) an L3 measurement report 204 including at least one valid measurement result of the second cell to network device 120. Network device 120 may then receive (230) the L3 measurement report 204 including at least one valid measurement result of the second cell from terminal device 110. Network device 120 may change the unknown state of the first cell to a known state based on receiving the L3 measurement report 204, or determine the TCI state of the first cell based on receiving the L3 measurement report 204 and continue activating the first cell as if it were known. In some embodiments, network device 120 may skip at least one of the automatic gain control portion or the cell search portion during the activation of the first cell. In some embodiments, the first cell and the second cell may be on the same frequency range 2 (FR2) band. Alternatively or additionally, the first cell and the second cell may be on the same FR1 band and be consecutive.

[0042] Based on L3 measurement report 204, network device 120 can transmit (235) a Transmission Configuration Indication (TCI) activation command 206 indicating the TCI state associated with the determined first cell to terminal device 110. Terminal device 110 can then receive (240) the TCI activation command 206 from network device 120. Alternatively or additionally, terminal device 110 can receive information from network device 120 indicating at least one condition for reporting L3 measurement report 204. Alternatively, at least one condition for reporting L3 measurement report can be predefined as a default condition, requiring no information from network device 120.

[0043] In some embodiments, the cell activation command 202 can be used to activate multiple cells, including the first cell, and the terminal device 110 can determine whether at least one condition is met for each of the multiple cells. In some embodiments, the same condition can be applied to multiple cells. Based on the determination that at least one cell among the multiple cells meets at least one condition, the terminal device 110 can transmit an L3 measurement report 204 to the network device 120.

[0044] Alternatively or additionally, based on the determination that multiple cells are on the same frequency band, terminal device 110 can determine whether valid measurement results for at least one of the multiple cells are available. Based on the determination that valid measurement results for at least one of the multiple cells are available, terminal device 110 can transmit an L3 measurement report to network device 120.

[0045] In some embodiments, cell activation command 202 can be used to activate multiple cells including a first cell, and terminal device 110 can determine a group of cells on the same frequency band among the multiple cells based on the determination that the multiple cells are on multiple frequency bands. Then, terminal device 110 can determine whether valid measurement results of at least one cell in the group of cells are available. Based on the determination that valid measurement results of at least one cell in the group of cells are available, terminal device 120 can transmit an L3 measurement report to network device 130.

[0046] In some further embodiments, based on the determination that at least one condition is not met, terminal device 110 may avoid transmitting the L3 measurement report to network device 120. Alternatively or additionally, the L3 measurement report 204 may include valid measurement results for all serving cells of the terminal device. The first cell may be a primary / secondary cell (PSCell) or a secondary cell (SCell).

[0047] Figure 3Several examples of sending an L3 report are illustrated according to some embodiments of this disclosure. It should be noted that process flow 300 can be considered as a further example of process flow 200. For example, UE 305 can be one of the example devices of terminal device 110. It should be understood that these devices are described for illustrative purposes only and do not imply any limitation on the scope of this disclosure. The process will be described in detail below.

[0048] The following example involves FR2 and FR1 scenarios, where an L3 report is triggered for a cell to be activated, but valid L3 measurements for that cell are unavailable. Figure 3 As shown, in a single SCell activation embodiment, UE 305 can be configured with a primary cell (PCell) 310, Cell1 (i.e., SCell1) 315, and Cell2 (i.e., SCell2) 320. Cell2 320 can be on the same FR2 band as Cell1 315, and only PCell 310 is activated.

[0049] At point 302, an RRC connection mode can be established between UE 305 and primary cell (PCell) 310. At point 304, PCell 310 can send SCell configuration or additional information to UE 305. At point 306, PCell 310 can also send a measurement configuration ('report on SCell Activation') to UE 305, instructing the UE to send an L3 report upon receiving the SCell activation command.

[0050] All SCells 315 and 320 may be unknown. In other words, UE 305 did not report any valid L3 measurements for SCells 315 and 320 for some period of time before the SCell activation command. Therefore, the network has no beam information about SCells 315 and 320. At 308, UE 305 may not be able to acquire valid L3 measurements for SCell1 315, but it may acquire valid L3 measurements for SCell2 320.

[0051] At 312, PCell 310 can send an SCell activation command for SCell1 315 to UE 305. At 314, UE 305 can evaluate L3 reporting conditions. According to this disclosure, for FR2, UE 305 can send a report if at least one valid measurement result exists in any serving cell on the same frequency band. Even if a valid L3 measurement result for the SCell to be activated is unavailable, but a valid L3 report is available for any other SCell on the same frequency band, all SCells on that frequency band can benefit from the L3 result and transition to a known state or undergo a cell activation process as if in a known state (by eliminating the AGC and cell search portions in subsequent steps of SCell activation). Here, serving cells on the same frequency band can include active serving cells and cells in a deactivated state.

[0052] For FR1, UE 305 can send a report if a valid measurement exists for any consecutive in-band SCells. This is because if the reported measurement is for any non-consecutive in-band or inter-band cell, the currently activating SCell may not benefit from the reduced SCell activation delay from the reported value, and therefore the UE may not trigger an L3 report. Otherwise, if UE 305 has valid L3 measurements for consecutive in-band SCells, UE 305 can share information such as AGC and time / frequency information between the activating SCell and its consecutive in-band SCells, thus enabling it to transition to a known state or perform the cell activation process as if it were a known state.

[0053] Alternatively, or in some embodiments, for the FR1 and FR2 bands, the UE 305 may send a report if there are valid measurements for any serving cell or any inactive serving cell (including deactivated SCells and active SCells).

[0054] In this embodiment, although UE 305 has no valid measurement results for the SCell1 to be activated, it can assess that SCell2 320 and SCell1 315 are on the same FR2 frequency band. At 316, UE 305 can determine to send an L3 report for all serving cells (such as PCell 310). UE 305 can determine whether valid measurement results are for SCells on the same frequency band. In the measurement report, UE 305 may include the L3 measurement results for SCell2 320 because it is on the same frequency band.

[0055] At 318, Cell1 315 becomes known or can be considered known to the network, and the AGC portion can be removed. At 322, the network can determine the Transport Configuration Indicator (TCI) based on L3 reports from other in-band SCells and send a TCI activation command to UE 305. At 324, PCell 310 can send an SP-CSI-RS activation command to UE 305. At 326 and 328, SCell1 315 can also send an SP-CSI-RS activation command for channel measurement to UE 305. At 330, when SCell activation is complete, the UE can send a valid CSI report to PCell 310.

[0056] In another example embodiment, assuming the same conditions as the example above, except that Cell2 320 is not on the same frequency band as Cell1 315, UE 305 may not report any L3 measurements because the reported information may not be helpful for SCell1 315 activation delay. UE 305 can use conventional SCell activation.

[0057] In a further example embodiment, it is assumed that multiple SCells are active. If Cell1 315 and Cell2 320 are on the same frequency band, the same process described in the single SCell activation embodiment can be applied to this embodiment. Therefore, after UE305 determines that cell1 315 and cell2 320 are both on the same frequency band, all cells on that frequency band become known, and the AGC portion can be removed from SCell activation by reporting the L3 measurement results of at least one of the cells. Therefore, L3 reporting enhancement can be applied to SCell activation.

[0058] In another example embodiment, if all SCells are not on the same frequency band, UE 305 may only report if it has a valid result for any SCell on a certain frequency band, i.e., it evaluates by frequency band. UE 305 may identify different frequency bands and assign cells to each of these frequency bands. Then, for each frequency band, UE 305 may determine if there is at least one valid L3 measurement, and UE 305 may include it in the measurement report and trigger an L3 report.

[0059] In the FR1 single SCell activation embodiment, if a valid measurement result exists for any consecutive in-band SCells, UE 305 may report the L3 measurement result. Otherwise, UE 305 may, by convention, not send any report. It should be noted that, in the context of this disclosure, these conditions can be used to at least determine whether an L3 report should be triggered. If triggered, the L3 report may include measurement results for the relevant SCell, inactive SCells, deactivated SCells, or valid measurement results for all serving cells.

[0060] In some embodiments, the network can instruct UE 305 whether to send an L3 report considering only the validity of the SCell to be activated or considering the validity of other relevant SCells. The above conditions can also be applied to multiple SCell activations. The difference lies in the evaluation conditions for each SCell to be activated.

[0061] If any serving cell has a valid result, UE 305 can report it. This is because including any valid result from the SCell can benefit the network by updating the known / unknown state of the SCell. By doing so, the most useful information is incorporated into the available measurement reports, which helps the network keep the cell state up-to-date from the UE's measurement perspective.

[0062] In this way, the drawbacks or ambiguities regarding the necessity of not sending measurement results are resolved. The aforementioned L3 reporting conditions can further clarify the current protocol if valid L3 measurement results for the cell to be activated are unavailable. If any of the above conditions are met, UE 305 can send L3 reports for all serving cells.

[0063] Figure 4 A flowchart of a method 400 implemented at a terminal device according to some example embodiments of the present disclosure is shown. For discussion purposes, method 400 will be referred to Figure 1A This is described from the perspective of terminal device 110.

[0064] At block 402, terminal device 110 can receive a cell activation command from network device for activating the first cell. At block 404, terminal device 110 can determine whether at least one condition of a Layer 3 (L3) measurement report is met. At block 406, based on the determination that at least one condition is met, terminal device 110 can send an L3 measurement report to network device including at least one valid measurement result of a second cell, wherein the second cell is different from the first cell.

[0065] In response to determining that a valid measurement result for the first cell is unavailable, terminal device 110 may determine whether at least one condition for reporting an L3 measurement report is met. In some example embodiments, at least one condition may include: a valid measurement result is available for at least one serving cell of the terminal device, and the at least one serving cell includes a second cell; a valid measurement result is available for at least one inactive cell of the terminal device, and the at least one inactive cell includes a second cell; the first cell is in frequency range 2 (FR2) band, and a valid measurement result is available for the terminal device's serving cell in the same FR2 band; the first cell is in FR1 band, a valid measurement result is available for the terminal device's serving cell, and the serving cell is in FR1 band and is contiguous with the first cell; the first cell is in frequency range 2 (FR2) band, and a valid measurement result is available for the terminal device's inactive cell in the same FR2 band; or the first cell is in FR1 band, a valid measurement result is available for the terminal device's inactive cell, and the inactive cell is in FR1 band and is contiguous with the first cell.

[0066] In some example embodiments, terminal device 110 may receive information from network device indicating at least one condition for reporting an L3 measurement report. In some further example embodiments, a cell activation command is used to activate a plurality of cells, including a first cell, and terminal device 110 may determine whether each of the plurality of cells meets at least one condition. Based on the determination that at least one cell among the plurality of cells meets at least one condition, terminal device 110 sends an L3 measurement report to network device.

[0067] In some example embodiments, the cell activation command is used to activate multiple cells, including a first cell, and based on determining that the multiple cells are on the same frequency band, the terminal device can determine whether at least one of the multiple cells has available valid measurement results. Based on determining that at least one of the multiple cells has available valid measurement results, the terminal device can send an L3 measurement report to the network device.

[0068] In some example embodiments, the cell activation command is used to activate multiple cells, including a first cell, and based on determining that the multiple cells are on multiple frequency bands, the terminal device 110 can identify a group of cells on the same frequency band among the multiple cells. The terminal device 110 can determine whether at least one cell in the group has available valid measurement results. Based on determining that at least one cell in the group has available valid measurement results, the terminal device 110 can send an L3 measurement report to the network device.

[0069] In some other embodiments, based on the determination that at least one of the conditions is not met, terminal device 110 may avoid sending an L3 measurement report to the network device. In some examples, the L3 measurement report includes valid measurement results for all serving cells of the terminal device. In some other embodiments, the first cell is a primary / secondary cell (PSCell) or a secondary cell (SCell).

[0070] Figure 5 A flowchart of a method 500 implemented at a network device according to some example embodiments of the present disclosure is shown. For discussion purposes, method 500 will be referred to Figure 1A This is described from the perspective of network device 120.

[0071] At block 502, network device 120 may send a cell activation command to terminal device for activating the first cell. At block 504, network device 120 may receive a Layer 3 (L3) measurement report from terminal device including at least one valid measurement result of the second cell. At block 506, network device 120 may send a Transmission Configuration Indicator (TCI) activation command to terminal device, indicating the TCI status associated with the first cell determined based on the L3 measurement report.

[0072] In some other embodiments, based on receiving L3 measurement reports, network device 120 can change the unknown state of the first cell to a known state. In some other embodiments, network device 120 can skip at least one of an automatic gain control portion or a cell search portion during first cell activation. In some other embodiments, the first cell and the second cell are on the same frequency range 2 (FR2) band. In some other embodiments, the first cell and the second cell are on the same FR1 band and are consecutive.

[0073] In some other embodiments, network device 120 may send information to terminal device indicating at least one condition of the L3 measurement report.

[0074] In some other embodiments, at least one condition includes at least one of the following: there are available valid measurements for at least one serving cell of the terminal device, and the at least one serving cell includes a second cell; there are available valid measurements for at least one inactive cell of the terminal device, and the at least one inactive cell includes a second cell; the first cell is in frequency range 2 (FR2) band and has available valid measurements for the serving cell of the terminal device in the same FR2 band; the first cell is in FR1 band, has available valid measurements for the serving cell of the terminal device, and the serving cell is in FR1 band and is contiguous with the first cell; the first cell is in frequency range 2 (FR2) band and has available valid measurements for the inactive cell of the terminal device in the same FR2 band; or the first cell is in FR1 band, has available valid measurements for the inactive cell of the terminal device, and the inactive cell is in FR1 band and is contiguous with the first cell.

[0075] In some other embodiments, the L3 measurement report includes valid measurement results for all serving cells of the terminal device. In some other embodiments, the first cell is a primary / secondary cell (PSCell) or a secondary cell (SCell).

[0076] In some embodiments, an apparatus capable of performing any of the methods in method 400 (e.g., terminal device 110) may include components for performing the various steps of method 400. These components may be implemented in any suitable form. For example, the components may be implemented in a circuit or software module.

[0077] In some embodiments, the apparatus includes components for receiving a cell activation command from a network device for activating a first cell. The apparatus includes components for determining whether at least one condition for reporting a Layer 3 (L3) measurement report is met. The apparatus includes components for sending an L3 measurement report to the network device, including at least one valid measurement result of a second cell, which is different from the first cell, based on the determination that at least one condition is met.

[0078] In some example embodiments, the apparatus includes components for determining whether at least one condition for reporting an L3 measurement report is met in response to determining that a valid measurement result for a first cell is unavailable. In some example embodiments, the apparatus includes components for at least one condition including: a valid measurement result is available for at least one serving cell of the terminal device, and the at least one serving cell includes a second cell; or a valid measurement result is available for at least one inactive cell of the terminal device, and the at least one inactive cell includes a second cell; the first cell is in the frequency range 2 (FR2) band and a valid measurement result is available for the serving cell of the terminal device in the same FR2 band; the first cell is in the FR1 band, a valid measurement result is available for the serving cell of the terminal device, and the serving cell is in the FR1 band and is contiguous with the first cell; the first cell is in the frequency range 2 (FR2) band and a valid measurement result is available for the inactive cell of the terminal device in the same FR2 band; or the first cell is in the FR1 band, a valid measurement result is available for the inactive cell of the terminal device, and the inactive cell is in the FR1 band and is contiguous with the first cell.

[0079] In some example embodiments, the apparatus includes components for receiving information from a network device indicating at least one condition for reporting an L3 measurement report. In some other example embodiments, a cell activation command is used to activate a plurality of cells, including a first cell, and the apparatus includes components for determining whether the at least one condition is met for each of the plurality of cells. The apparatus includes components for sending an L3 measurement report to the network device based on the determination that at least one of the plurality of cells meets the at least one condition.

[0080] In some example embodiments, the cell activation command is used to activate a plurality of cells, including a first cell, and the apparatus includes components for determining whether at least one of the plurality of cells has a valid measurement result based on the determination that the plurality of cells are in the same frequency band. The apparatus also includes components for sending an L3 measurement report to a network device based on the determination that at least one of the plurality of cells has a valid measurement result.

[0081] In some example embodiments, the cell activation command is used to activate a plurality of cells, including a first cell, and the apparatus includes components for determining a group of cells in the same frequency band among the plurality of cells based on determining that the plurality of cells are in multiple frequency bands. The apparatus includes components for determining whether at least one cell in the group of cells has a valid measurement result. The apparatus includes components for sending an L3 measurement report to a network device based on determining that at least one cell in the group of cells has a valid measurement result.

[0082] In some other embodiments, the apparatus includes components for preventing the transmission of L3 measurement reports to the network device based on the determination that at least one condition is not met. In some examples, the apparatus includes components for the L3 measurement report to include valid measurement results of all serving cells of the terminal device. In some other embodiments, the apparatus includes components for determining whether the first cell is a primary secondary cell (PSCell) or a secondary cell (SCell).

[0083] In some embodiments, the apparatus further includes components for performing additional steps in some embodiments of method 400. In some embodiments, the components include at least one processor and at least one memory including computer program code configured to enable the apparatus to operate together with the at least one processor.

[0084] In some embodiments, an apparatus capable of performing any of the methods 500 (e.g., network device 120) may include components for performing the corresponding steps of method 500. These components may be implemented in any suitable form. For example, the components may be implemented in a circuit or software module.

[0085] In some embodiments, the apparatus includes components for sending a cell activation command to a terminal device for activating a first cell. In some embodiments, the apparatus includes components for receiving a Layer 3 (L3) measurement report from the terminal device that includes at least one valid measurement result of a second cell. In some embodiments, the apparatus includes components for sending a Transmission Configuration Indicator (TCI) activation command to the terminal device that indicates the TCI state associated with the first cell determined based on the L3 measurement report.

[0086] In some embodiments, the apparatus includes components for changing an unknown state of a first cell to a known state based on received L3 measurement reports. In some other embodiments, the apparatus includes components for skipping at least one of an automatic gain control section or a cell search section during the activation of the first cell. In some other embodiments, the apparatus includes components for ensuring that the first cell and the second cell are in the same frequency range 2 (FR2) band. In some other embodiments, the apparatus includes components for ensuring that the first cell and the second cell are in the same FR1 band and are consecutive.

[0087] In some other embodiments, the apparatus includes components for sending information to a terminal device indicating at least one condition for reporting an L3 measurement report.

[0088] In some other embodiments, the apparatus includes components for at least one condition including at least one of the following: at least one serving cell of the terminal device has a valid measurement result, and the at least one serving cell includes a second cell; or at least one inactive cell of the terminal device has a valid measurement result, and the at least one inactive cell includes a second cell; a first cell is in the frequency range 2 (FR2) band, and the terminal device has a valid measurement result for a serving cell in the same FR2 band; a first cell is in the FR1 band, the terminal device has a valid measurement result for a serving cell, and the serving cell is in the FR1 band and is continuous with the first cell; a first cell is in the frequency range 2 (FR2) band, and the terminal device has a valid measurement result for an inactive cell in the same FR2 band; or a first cell is in the FR1 band, the terminal device has a valid measurement result for an inactive cell, and the inactive cell is in the FR1 band and is continuous with the first cell.

[0089] In some other embodiments, the apparatus includes components for L3 measurement reporting of valid measurement results for all serving cells of the terminal device. In some other embodiments, the apparatus includes components for determining whether the first cell is a primary secondary cell (PSCell) or a secondary cell (SCell).

[0090] In some embodiments, the apparatus further includes components for performing other steps in some embodiments of method 500. In some embodiments, the components include at least one processor and at least one memory including computer program code configured to, together with the at least one processor, cause the apparatus to operate.

[0091] Figure 6 A simplified block diagram of a device 600 suitable for implementing some example embodiments of the present disclosure is shown. Device 600 may be provided to implement communication devices, such as terminal device 110 and network device 120 as shown in FIG1. ​​As shown, device 600 includes one or more processors 610, one or more memories 620 coupled to processor 610, and one or more communication modules 640 coupled to processor 610.

[0092] Communication module 640 is used for bidirectional communication. Communication module 640 has at least one antenna to facilitate communication. The communication interface can represent any interface necessary for communicating with other network elements.

[0093] Processor 610 can be any type suitable for a local technology network and can include one or more of the following: general-purpose computer, special-purpose computer, microprocessor, digital signal processor (DSP), and processor based on a multi-core processor architecture, as non-limiting examples. Device 600 can have multiple processors, such as application-specific integrated circuit chips that are time-dependent on a clock of a synchronous main processor.

[0094] Memory 620 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memories include, but are not limited to, read-only memory (ROM) 624, electrically programmable read-only memory (EPROM), flash memory, hard disk, optical disc (CD), digital video disc (DVD), and other magnetic and / or optical storage. Examples of volatile memories include, but are not limited to, random access memory (RAM) 622 and other volatile memories that do not persist during power outages.

[0095] Computer program 630 includes computer-executable instructions that are executed by the associated processor 610. Program 630 may be stored in ROM 624. Processor 610 may perform any suitable actions and processes by loading program 630 into RAM 622.

[0096] The embodiments of this disclosure can be implemented via program 630, enabling device 600 to execute the reference. Figure 2 Any process discussed in this disclosure. Embodiments of this disclosure may also be implemented by hardware or by a combination of software and hardware.

[0097] In some example embodiments, program 630 may be tangibly contained in a computer-readable medium, which may be included in device 600 (e.g., in memory 620) or in other storage devices accessible to device 600. Device 600 may load program 630 from the computer-readable medium into RAM 622 for execution. The computer-readable medium may include any type of tangible non-volatile storage, such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc.

[0098] Figure 7 A block diagram of an example of a computer-readable medium 700 according to some exemplary embodiments of the present disclosure is shown. A program 630 is stored on the computer-readable medium 700. It should be noted that although the computer-readable medium 700... Figure 7 The program is depicted in the form of a CD or DVD, but the computer-readable medium 700 may be any other form suitable for carrying or storing the program 630.

[0099] Generally, the various embodiments of this disclosure can be implemented in hardware or dedicated circuitry, software, logic, or any combination thereof. Some aspects can be implemented in hardware, while others can be implemented in firmware or software executable by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of this disclosure are shown and described as block diagrams, flowcharts, or using some other graphical representation, it should be understood that the blocks, apparatuses, systems, techniques, or methods described herein can be implemented in hardware, software, firmware, dedicated circuitry or logic, general-purpose hardware or controllers or other computing devices, or some combination thereof, as non-limiting examples.

[0100] This disclosure also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as those contained in program modules, which execute in a device on a real or virtual target processor to perform the functions described above. Figure 5 Alternatively, the method described in 6, 500 or 600. Typically, a program module includes routines, programs, libraries, objects, classes, components, data structures, etc., that perform specific tasks or implement specific abstract data types. The functionality of a program module can be combined or split among program modules as needed in various embodiments. The machine-executable instructions of a program module can be executed locally or on a distributed device. In a distributed device, the program module can reside on both local and remote storage media.

[0101] Program code used to perform the methods of this disclosure may be written in any combination of one or more programming languages. This program code may be provided to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus, such that, when executed by the processor or controller, the program code enables the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a machine, partially on a machine, as a stand-alone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0102] In the context of this disclosure, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, etc.

[0103] Computer-readable media can be computer-readable signal media or computer-readable storage media. Computer-readable media can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any suitable combination thereof. More specific examples of computer-readable storage media will include electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable optical disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. As used herein, the term "non-transient" is a limitation on the medium itself (i.e., tangible, not signaling), not on the persistence of data storage (e.g., RAM versus ROM).

[0104] Furthermore, although the operations are depicted in a specific order, this should not be construed as requiring that such operations be performed in the specific order shown or sequentially, or that all the operations shown be performed to achieve the desired result. In some cases, multitasking and parallel processing may be advantageous. Similarly, while several specific implementation details are included in the foregoing discussion, these should not be construed as limiting the scope of this disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features described in the context of a single embodiment may also be implemented in combination in a single embodiment. Conversely, the various features described in the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments.

[0105] Although this disclosure has been described in language specific to structural features and / or methodological actions, it should be understood that this disclosure as defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are disclosed as examples of implementing the claims.

Claims

1. A terminal device, comprising: At least one processor; as well as At least one memory stores instructions that, when executed by the at least one processor, cause the terminal device to at least: Receive a cell activation command from the network device to activate the first cell; Determine whether at least one condition for reporting layer 3 (L3) measurement reports is met; as well as Based on the determination that at least one condition is met, the L3 measurement report is sent to the network device, the L3 measurement report including at least one valid measurement result for a second cell, wherein the second cell is different from the first cell.

2. The terminal device as claimed in claim 1, wherein the terminal device is further configured to: In response to determining that a valid measurement result for the first cell is unavailable, determine whether at least one condition for reporting the L3 measurement report is met.

3. The terminal device as claimed in claim 1 or 2, wherein the at least one condition includes at least one of the following: Valid measurement results for at least one serving cell of the terminal device are available, and the at least one serving cell includes the second cell; Valid measurement results are available for at least one inactive cell of the terminal device, and the at least one inactive cell includes the second cell; The first cell is in the frequency range 2 (FR2) band, and valid measurement results for the serving cell of the terminal device in the same FR2 band are available; The first cell is in the FR1 band, and valid measurement results for the serving cell of the terminal device are available, and the serving cell is in the FR1 band and is continuous with the first cell; The first cell is in the frequency range 2 (FR2) band, and valid measurement results for the terminal device in an inactive cell in the same FR2 band are available; or The first cell is in the FR1 band, and valid measurement results for the inactive cell of the terminal device are available, and the inactive cell is in the FR1 band and is continuous with the first cell.

4. The terminal device as claimed in any one of claims 1 to 3, wherein the terminal device is further configured to: Receive information from the network device indicating at least one condition for reporting the L3 measurement report.

5. The terminal device as claimed in any one of claims 1 to 4, wherein the cell activation command is used to activate a plurality of cells including the first cell, and the terminal device is further configured to: For each of the multiple cells, determine whether at least one condition is met; and Based on the determination that at least one of the plurality of cells meets the at least one condition, the L3 measurement report is sent to the network device.

6. The terminal device as claimed in any one of claims 1 to 4, wherein the cell activation command is used to activate a plurality of cells including the first cell, and the terminal device is further configured to: Based on determining that the plurality of cells are on the same frequency band, it is determined whether valid measurement results for at least one of the plurality of cells are available; and Based on the determination that a valid measurement result for at least one of the plurality of cells is available, the L3 measurement report is sent to the network device.

7. The terminal device as claimed in any one of claims 1 to 4, wherein the cell activation command is used to activate a plurality of cells including the first cell, and the terminal device is further configured to: Based on determining that the multiple cells are on multiple frequency bands, a set of cells on the same frequency band among the multiple cells is determined. Determine whether valid measurement results are available for at least one cell in the cell set; as well as Based on the determination that valid measurement results for at least one cell in the cell set are available, the L3 measurement report is sent to the network device.

8. The terminal device as claimed in any one of claims 1 to 7, wherein the terminal device is further configured to: Based on the determination that none of the at least one of the conditions is met, the transmission of the L3 measurement report to the network device is prevented.

9. The terminal device as claimed in any one of claims 1 to 8, wherein the L3 measurement report includes valid measurement results for all serving cells of the terminal device.

10. The terminal device according to any one of claims 1 to 9, wherein the first cell is a primary secondary cell (PSCell) or a secondary cell (SCell).

11. A network device, comprising: At least one processor; as well as At least one memory stores instructions that, when executed by the at least one processor, cause the network device to at least: Send a cell activation command to the terminal device to activate the first cell; The terminal device receives a Layer 3 (L3) measurement report, which includes at least one valid measurement result for the second cell; as well as A Transmission Configuration Indicator (TCI) activation command is sent to the terminal device, the TCI activation command indicating the TCI status associated with the first cell as determined based on the L3 measurement report.

12. The network device of claim 11, wherein the network device is further configured to: Based on the received L3 measurement report, the unknown state of the first cell is changed to a known state.

13. The network device according to claim 11 or 12, wherein the network device is further configured to: During the activation of the first cell, skip at least one of the automatic gain control section or the cell search section.

14. The network device according to any one of claims 11 to 13, wherein at least one of the following: The first cell and the second cell are on the same frequency range 2 (FR2) band; or The first cell and the second cell are on the same FR1 frequency band and are consecutive.

15. The network device according to any one of claims 11 to 14, wherein the network device is further configured to: Send information to the terminal device indicating at least one condition for reporting the L3 measurement report.

16. The network device of claim 15, wherein the at least one condition includes at least one of the following: Valid measurement results for at least one serving cell of the terminal device are available, and the at least one serving cell includes the second cell; Valid measurement results are available for at least one inactive cell of the terminal device, and the at least one inactive cell includes the second cell; The first cell is in the frequency range 2 (FR2) band, and valid measurement results for the serving cell of the terminal device in the same FR2 band are available; The first cell is in the FR1 band, and valid measurement results for the serving cell of the terminal device are available, and the serving cell is in the FR1 band and is continuous with the first cell; The first cell is in the frequency range 2 (FR2) band, and valid measurement results for the terminal device in an inactive cell in the same FR2 band are available; or The first cell is in the FR1 band, and valid measurement results for the inactive cell of the terminal device are available, and the inactive cell is in the FR1 band and is continuous with the first cell.

17. The network device according to any one of claims 11 to 16, wherein the L3 measurement report includes valid measurement results for all serving cells of the terminal device.

18. The network device according to any one of claims 11 to 17, wherein the first cell is a primary secondary cell (PSCell) or a secondary cell (SCell).

19. A method comprising: Receive a cell activation command from the network device to activate the first cell; Determine whether at least one condition for reporting layer 3 (L3) measurement reports is met; as well as Based on the determination that at least one condition is met, the L3 measurement report is sent to the network device, the L3 measurement report including at least one valid measurement result for a second cell, wherein the second cell is different from the first cell.

20. A method comprising: Send a cell activation command to the terminal device to activate the first cell; The terminal device receives a Layer 3 (L3) measurement report, which includes at least one valid measurement result for the second cell; as well as A Transmission Configuration Indicator (TCI) activation command is sent to the terminal device, the TCI activation command indicating the TCI status associated with the first cell as determined based on the L3 measurement report.

21. An apparatus comprising: A component for receiving a cell activation command from a network device to activate a first cell; A component for determining whether at least one condition for reporting layer 3 (L3) measurement reports is met; as well as A component for sending the L3 measurement report to the network device based on determining that at least one condition is met, the L3 measurement report including at least one valid measurement result for a second cell, wherein the second cell is different from the first cell.

22. An apparatus comprising: A component used to send a cell activation command to a terminal device to activate the first cell; A component for receiving from the terminal device a Layer 3 (L3) measurement report including at least one valid measurement result for the second cell; as well as A component for sending a Transmission Configuration Indication (TCI) activation command to the terminal device, the TCI activation command indicating the TCI status associated with the first cell based on the L3 measurement report.

23. A non-transitory computer-readable medium comprising program instructions that, when executed by a device, cause the device to perform at least the method of any one of claims 19 to 20.

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