Handling csi-rs measurement

Abstract

To handle channel state information reference signal measurement.SOLUTION: An embodiment according to the present disclosure relates to a method, a device, and a computer-readable storage medium of communication. The method implemented in a first device includes determining, at the first device, first timing of a channel state information reference signal from a target cell. The first device is configured by a second device for measuring the channel state information reference signal. The method includes determining second timing used by the first device to measure the channel state information reference signal. The method further includes determining the timing difference between the second timing and the first timing. The method further includes transmitting, to the second device, information regarding the measurement of the channel state information reference signal on the basis of the timing difference.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE

[0002] Embodiments of the present disclosure relate generally to the field of telecommunications, and more particularly to devices, methods, and computer-readable storage media for processing channel state information reference signal (CSI-RS) measurements. [Background technology]

[0002] CSI-RS is designed for tracking and beam management, as well as for Layer 3 (L3) mobility management, and therefore for handover (HO). Compared with synchronization signal block (SSB)-based measurements, CSI-RS-based L3 measurements can provide finer beam information. Thus, CSI-RS-based L3 measurements enable a network device to handover a user equipment (UE) directly to a more refined beam in a target cell during a handover procedure. CSI-RS-based L3 measurements are affected by network synchronization as well as the alignment of received signals from different cells at the UE. These aspects together raise the problem of how to handle when there is a synchronization problem with CSI-RS-based L3 measurements. Summary of the Invention

[0003] Generally, the example embodiments of the present disclosure provide a solution for processing of CSI-RS measurements.

[0004] In a first aspect, a first device is provided, the first device comprising at least one processor and at least one memory including computer program code, the at least one memory and the computer program code including the steps of: determining, with the at least one processor, in the first device a first timing of a channel state information reference signal from a target cell, the first device being configured to measure the channel state information reference signal by a second device; and determining, by the first device, a second timing used to measure the channel state information reference signal; The device is configured to perform the steps of: determining a timing difference between the first timing and the second timing; and transmitting information regarding the measurement of the channel state information reference signal to the second device based on the timing difference.

[0005] In a second aspect, a second device is provided, the second device comprising at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured, with the at least one processor, to cause the second device to configure the first device to measure a channel state information reference signal from a target cell and to receive from the first device information related to the measurement of the channel state information reference signal based on a timing difference between a first timing of the channel state information reference signal and a second timing used by the first device to measure the channel state information reference signal.

[0006] In a third aspect, a method is provided, comprising the steps of: determining, at a first device, a first timing of a channel state information reference signal from a target cell, the first device being configured to measure the channel state information reference signal by the second device, determining a second timing used by the first device to measure the channel state information reference signal, determining a timing difference between the first timing and the second timing, and transmitting information regarding the measurement of the channel state information reference signal to the second device based on the timing difference.

[0007] In a fourth aspect, a method is provided, comprising: configuring a first device in a second device to measure a channel state information reference signal from a target cell, and receiving from the first device information related to measuring the channel state information reference signal based on a timing difference between a first timing of the channel state information reference signal and a second timing used by the first device to measure the channel state information reference signal.

[0008] In a fifth aspect, a first device is provided, comprising: means for determining a first timing of a channel state information reference signal from a target cell, where the first device is configured by a second device to measure the channel state information reference signal, means for determining a second timing used by the first device to measure the channel state information reference signal, means for determining a timing difference between the first timing and the second timing, and means for transmitting information regarding the measurement of the channel state information reference signal to the second device based on the timing difference.

[0009] In a sixth aspect, a second apparatus is provided, comprising: means for configuring the first apparatus to measure a channel state information reference signal from a target cell; and means for receiving from the first apparatus information related to the measurement of the channel state information reference signal based on a timing difference between a first timing of the channel state information reference signal and a second timing used by the first device to measure the channel state information reference signal.

[0010] In a seventh aspect, there is provided a computer readable medium comprising program instructions for causing an apparatus to perform at least a method according to the third aspect.

[0011] In an eighth aspect, there is provided a computer readable medium comprising program instructions for causing an apparatus to perform at least a method according to the fourth aspect.

[0012] It should be understood that the Summary of the Invention section is not intended to identify key or essential features of the embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will be readily understood by the following description. [Brief description of the drawings]

[0013] Several example embodiments will now be described with reference to the accompanying drawings. [Figure 1] FIG. 1 illustrates an example communication network in which example embodiments of the present disclosure may be implemented. [Diagram 2] FIG. 2 shows a schematic diagram of the timing difference between different cells. [Diagram 3] FIG. 3 illustrates a flow chart illustrating an example process for processing CSI-RS measurements according to some embodiments of the present disclosure. [Figure 4] FIG. 4 illustrates a flowchart illustrating an example process for processing CSI-RS measurements in accordance with certain embodiments of the present disclosure. [Diagram 5] FIG. 5 illustrates a flow chart illustrating an example process for processing CSI-RS measurements according to some embodiments of the present disclosure. [Figure 6] FIG. 6 illustrates a flowchart illustrating an example process for processing CSI-RS measurements in accordance with certain embodiments of the present disclosure. [Figure 7] FIG. 7 illustrates a flowchart of an exemplary method according to some embodiments of the present disclosure. [Figure 8] FIG. 8 illustrates a flowchart of an exemplary method according to some embodiments of the present disclosure. [Figure 9] FIG. 9 illustrates a simplified block diagram of a device suitable for practicing exemplary embodiments of the present disclosure. [Figure 10] FIG. 10 illustrates a block diagram of an exemplary computer-readable medium according to an exemplary embodiment of the present disclosure.

[0014] Throughout the drawings, the same or similar reference numbers represent the same or similar elements. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Next, the principles of the present disclosure will be described with reference to some exemplary embodiments. It should be understood that these embodiments are described for illustrative purposes only, to assist those skilled in the art in understanding and implementing the present disclosure, and are not intended to imply any limitations on the scope of the present disclosure. It should be noted that the present invention can be implemented in various forms other than those described below.

[0016] Unless otherwise defined in the following description and claims, 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 belongs.

[0017] References in this disclosure to "an embodiment," "one embodiment," "an exemplary embodiment," and the like indicate that the described embodiment may include a particular feature, structure, or characteristic, but not all embodiments need to include the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. Furthermore, it is submitted that when a particular feature, structure, or characteristic is described in connection with an embodiment, it is within the knowledge of one of ordinary skill in the art to affect such feature, structure, or characteristic in connection with other embodiments, whether or not explicitly described.

[0018] Although terms such as "first" and "second" may be used herein to describe various elements, it should be understood that 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 can be referred to as a second element, and similarly, a second element can 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.

[0019] The terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the exemplary embodiments. As used herein, the singular forms "a," "an," and "the" are intended to include the plural unless the context clearly indicates otherwise. The terms "comprises," "comprising," "has," "having," "includes," and / or "including," as used herein, specify the presence of stated features, elements, and / or components, etc., but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof.

[0020] As used in this application, the term "circuitry" may refer to one or more or all of the following: (a) Hardware-only circuit implementations (e.g., analog and / or digital-only implementations); and (b) (where applicable) any combination of hardware circuitry and software; (i) A combination of analog and / or digital hardware circuitry and software / firmware; and (ii) any portion of software (including digital signal processors), software, and hardware processors having memory that work together to cause a device, such as a mobile phone or server, to perform various functions; (c) Hardware circuits and / or processors, such as microprocessors or portions of microprocessors, that require software (e.g., firmware) to operate, may not require the software to be present when it is not needed for operation.

[0021] This definition of circuitry applies to all uses of the term in this application, including any claims. As a further example, as used in this application, the term circuitry also encompasses merely a hardware circuitry or processor (or processors), or a portion of a hardware circuitry or processor, and its (or their) associated software and / or firmware implementation. The term circuitry also encompasses, for example, baseband or processor integrated circuits for mobile devices or similar integrated circuits in servers, cellular network devices, or other computing or network devices, where applicable to certain claim elements.

[0022] As used herein, the term "communication network" refers to a network conforming to any suitable communication standard, such as Long Term Evolution (LTE), LTE Advanced (LTE-A), 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 the communication network may be performed according to any suitable generation communication protocol, including, but not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, future fifth generation (5G) communication protocols, and / or any other protocols currently known or to be developed in the future. The embodiments of the present disclosure may be applied to various communication systems. Considering the rapid development in communication, there are of course future types of communication technologies and systems in which the present disclosure can be implemented. The technical scope of the present disclosure should not be considered as being limited only to the above-mentioned systems.

[0023] As used herein, the term "network device" refers to a node in a communication network through which a terminal device accesses the network and receives services therefrom. Depending on the terminology and technology applied, a network device may refer to a base station (BS) or an access point (AP), e.g., a Node B (Node B or NB), an evolved Node B (eNode B or eNB), an NR NB (also called gNB), a remote radio unit (RRU), a radio header (RH), a remote radio head (RRH), a repeater, a low power node such as femto, pico, etc.

[0024] The term "terminal device" refers to any end device that may be capable of wireless communication. By way of example and not limitation, a terminal device may be referred to as a communication device, user equipment (UE), subscriber station (SS), portable subscriber station, mobile station (MS), or access terminal (AT). Terminal devices may include, but are not limited to, mobile phones, cell 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 recording and playback equipment, vehicle wireless terminal devices, wireless endpoints, mobile stations, laptop embedded equipment (LEE), laptop mounted equipment (LME), USB dongles, smart devices, wireless customer premises equipment (CPE), Internet of Things (loT) devices, watches or other wearables, head mounted displays (HMD), 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 contexts), consumer electronic 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" may be used interchangeably.

[0025] As used herein, a measurement is defined as a "CSI-RS-based intra-frequency measurement" or "intra-frequency measurement" if one or more of the following are met: the subcarrier spacing (SCS) of the CSI-RS resource on the neighboring cell configured for measurement is the same as the subcarrier spacing of the CSI-RS resource on the serving cell indicated for measurement, the cyclic prefix (CP) type of the CSI-RS resource on the neighboring cell configured for measurement is the same as the CP type of the CSI-RS resource on the serving cell indicated for measurement, and the center frequency of the CSI-RS resource on the neighboring cell configured for measurement is the same as the center frequency of the CSI-RS resource on the serving cell indicated for measurement. Otherwise, the measurement is defined as a "CSI-RS-based inter-frequency measurement" or "inter-frequency measurement" for short.

[0026] 1 illustrates an exemplary communication environment 100 in which embodiments of the present disclosure may be implemented. As illustrated in FIG. 1, the environment 100 includes a first device 110, a second device 120, and a third device 130. In some exemplary embodiments, the first device 110 may be a terminal device, the second device 120 may be a network device serving the first device 110, and the third device 130 may be a network device neighboring the second device 120. The second device 120 provides a cell 121 for the first device 110, which may be referred to as a serving cell 121. The third device 130 provides a cell 131 for the first device 110, which may be referred to as a target cell 131. In some exemplary embodiments, the target cell 130 is a neighboring cell.

[0027] It should be understood that the number and types of first, second, and third devices as shown in FIG. 1 are for illustrative purposes only, without implying any limitation. The environment 100 may include any suitable number and type of first, second, and third devices adapted to implement embodiments of the present disclosure. For example, in some other exemplary embodiments, the third device may not be present, and both the target cell 131 and the serving cell 121 are provided by the second device 120.

[0028] 1, the first, second, and third devices 110, 120, and 130 may communicate with each other. For example, the second device 120 and the third device 130 may transmit a reference signal (e.g., CSI-RS) on a given resource, and the first device 110 may receive the reference signal based on configuration information for the given resource. Furthermore, the first device 110 may measure the reference signal and transmit the measurement result to the second device 120.

[0029] Communications in the communication environment 100 may be implemented according to any suitable communications protocol, including, but not limited to, cellular communications protocols such as first generation (1G), second generation (2G), third generation (3G), fourth generation (4G) and fifth generation (5G), wireless local network communications protocols such as Institute of Electrical and Electronics Engineers (IEEE) 802.11, and / or any other protocols now known or to be developed in the future. Furthermore, communications may utilize any suitable wireless communications technology, including, but not limited to, code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), frequency division duplex (FDD), time division duplex (TDD), multiple-input multiple-output (MIMO), orthogonal frequency division multiplexing (OFDM), discrete Fourier transform spread OFDM (DFT-s-OFDM), and / or any other technology now known or to be developed in the future.

[0030] The second device 120 may configure the first device 110 to measure at least CSI-RS from the target cell 131. In some example embodiments, the second device 120 may configure the first device 110 to measure CSI-RS from a set of cells that includes the target cell 131. In the following, such cells may be referred to collectively as "measurement target cells" or individually as "measurement target cells."

[0031] Measurement requirements for CSI-RS based L3 measurements include, for example, aspects of CSI-RS measurement bandwidth for minimum requirements, CSI-RS based intra-frequency and inter-frequency definitions, intra-frequency and inter-frequency measurement requirements, accuracy assessment and specification, additional UE measurement capabilities including number of frequency layers and number of cells, and performance requirements. Additionally, in aspects of synchronization assumptions, a single Fast Fourier Transform (FFT) may be assumed for multiple cell measurements per frequency layer for both intra-frequency and inter-frequency measurements in some scenarios.

[0032] Currently, the information element (IE) CSI-RS-ResourceConfigMobility is used to configure CSI-RS based L3 measurements. The network can configure the UE to perform L3 CSI-RS for mobility by configuring the UE with the IE CSI-RS-ResourceConfigMobility. This IE can be included in the MeasObjectNR, which is carrier specific. Thus, the network can configure CSI-RS for L3 mobility for one or more carriers. The IE CSI-RS-ResourceConfigMobility indicates the CSI-RS resources to be measured in each cell on a given carrier, where each CSI-RS resource is identified by an index.

[0033] If an associated SSB is configured, the UE determines the timing of the CSI-RS resources indicated in CSI-RS-Resource-Mobility based on the timing of the cell indicated by cellId in CSI-RS-CellMobility. In this case, the UE needs to detect this associated SSB and the cell indicated by cellId (SS / PBCH block) before measuring the associated CSI-RS.

[0034] Since the configuration options are very flexible, it was agreed to define requirements for CSI-RS based measurements in Rel16 with a limited scope. The requirements are defined in Rel16 only if an associated SSB is configured and discovered. The motivation is to not limit the overall use of CSI-RS based measurements for L3 mobility to synchronized scenarios only.

[0035] When an associated SSB is configured, the UE does not need to measure the associated CSI-RS resource for L3 mobility before the SS / PBCH block indicated by this associated SSB and cellId is detected. Therefore, the UE needs to detect the associated SSB to obtain timing information of the target cell before it can perform measurements on the corresponding CSI-RS resource (for L3 measurements). The target cell to be measured may or may not be synchronized with the serving cell.

[0036] However, as mentioned above, there is a single FFT synchronization assumption, i.e., a single FFT is used by the UE to enable simultaneous processing of CSI-RS (for L3 measurements) from multiple neighboring cells on one carrier.

[0037] If no synchronization is assumed between cells, there may be a timing difference between the CSI-RS resources measured at the UE and the timing of the single FFT. This complicates the use of a single FFT at the UE side to perform the required measurements. For example, FIG. 2 shows a schematic diagram 200 of timing differences between different cells. In the example shown in FIG. 2, the UE may apply a single FFT within a window 201. Under the above assumptions regarding synchronization, the UE may apply a single FFT to decode CSI-RS 211 and CSI-RS 212 from a first neighboring cell and CSI-RS 221 and CSI-RS 222 from a second neighboring cell.

[0038] For intra-frequency CSI-RS based measurements, the UE may assume that it uses the timing of the serving cell for a single FFT. As shown in Figure 2, there may be a timing difference T1 between the serving cell and the first neighboring cell. There may be a different timing difference T2 between the serving cell and the second neighboring cell. If the timing difference exceeds a certain threshold, such as the length of several CPs, the CSI-RS measurement performance may degrade.

[0039] The degradation of CSI-RS measurement performance due to timing differences can be related to several aspects. One aspect is the cell phase synchronization accuracy at the network side, i.e., how well the cells are synchronized at the network side. Currently, the Third Generation Partnership Project (3GPP) defines a maximum 3us cell phase synchronization accuracy in TS 38.133. Another aspect is the impact from downlink (DL) transmission delays from the network to the UE from different cells. Such DL transmission delays also affect the cell synchronization as observed at the UE side and whether the cell to be measured is considered well synchronized. Such DL transmission delays are not known at the UE side as well as the network side and cannot be set as a fixed value since they depend on the air interface and channel conditions.

[0040] Therefore, the impact of timing differences needs to be considered under the single FFT assumption. However, none of the existing solutions addressed the synchronization issue from the UE measurement perspective. A solution is needed on how to address CSI-RS measurements and related UE behavior regarding CSI-RS measurements and reporting of CSI-RS measurements.

[0041] According to some example embodiments of the present disclosure, a solution for processing CSI-RS based L3 measurements is provided. In this solution, a first device determines a first timing of CSI-RS from a target cell. The first device is configured by a second device to measure CSI-RS from the target cell. The first device then determines a second timing used by the first device to measure CSI-RS. The first device then determines a timing difference between the first timing and the second timing. Based on the timing difference, the first device transmits information regarding the measurement of CSI-RS to the second device, which may be referred to hereinafter as CSI-RS measurement. As used herein, the expression "measure CSI-RS" and variants thereof mean to perform a measurement on a CSI-RS resource.

[0042] In this solution, the behavior of the terminal device (e.g., UE) with respect to CSI-RS measurements is determined based on the timing difference, e.g., the timing difference observed at the UE. This solution can reduce the impact of large timing differences, especially under the assumption of a single FFT on the UE side. In this way, degradation of the reported CSI-RS measurements can be known or avoided on the network side when / if a CSI-RS measurement synchronization problem occurs.

[0043] In some example embodiments, if the timing difference is below a threshold, the first device may perform a CSI-RS measurement and report the result of the CSI-RS measurement to the second device. If the timing difference exceeds the threshold, the first device may not perform a CSI-RS measurement and may indicate to the second device that CSI-RS cannot or was not measured because the timing difference exceeds the threshold. Alternatively, if the timing difference exceeds the threshold, the first device may continue to monitor the timing difference. If the timing difference is below the threshold, the first device may perform a CSI-RS measurement.

[0044] In such an exemplary embodiment, it is ensured that the reported result of the CSI-RS measurement by the first device has a qualified accuracy. If the timing difference is large, unnecessary CSI-RS measurement effort can be reduced or even avoided at the first device (e.g., UE side). Furthermore, an indication to the second device (e.g., network device) can help the second device understand the issue and not configure measurements on the target cell. Furthermore, it can help the second device know the quality or accuracy of the measurement reported from the first device.

[0045] In some example embodiments, the first device may perform a CSI-RS measurement and report a result of the CSI-RS measurement regardless of whether the timing difference exceeds a threshold. In this case, the first device may further indicate to the second device whether the timing difference exceeds a threshold, e.g., in the measurement result, in the measurement report, or using some other separate message.

[0046] In such an example embodiment, the results of the CSI-RS measurements are reported to the second device along with an indication of whether the timing difference exceeds a threshold. In this way, the second device (e.g., a network device) can know whether the reported results are accurate. For example, the reported results can carry a particular value or indicator that indicates whether the reported results are accurate.

[0047] Some example embodiments will now be described in detail below. Figure 3 shows a flow chart illustrating an example process 300 for processing CSI-RS measurements according to some embodiments of the present disclosure. For illustrative purposes, the process 300 will be described with reference to Figure 1. The process 300 includes at least a first device 110 and a second device 120 as shown in Figure 1.

[0048] As shown, the second device 120 configures the first device 110 to measure CSI-RS from a target cell 131, which may be referred to as a “target CSI-RS,” at 305. The second device 120 may transmit a configuration for CSI-RS measurements to the first device 110. The configuration for CSI-RS measurements may comprise an indication of an SSB associated with the configured CSI-RS, which may be referred to as an “associated SSB.” For example, the second device 120 may transmit an IE CSI-RS-ResourceConfigMobility or other appropriate IE to the first device 110, which may include an index of the associated SSB. In addition to the target cell 131, in some demonstrative embodiments, the second device 120 may configure the first device 110 to measure CSI-RS from one or more other cells.

[0049] The first device 110 determines 310 a timing of the CSI-RS from the target cell 131 (also referred to as a "first timing"). The first timing may be a DL timing of the target cell 131 and may be determined by any suitable method. In one example, the first timing may be determined based on an associated SSB of the target cell 131. The associated SSB of the target cell 131 may be configured. For example, an index of the associated SSB may be included in the configuration for CSI-RS measurement. The first device 110 may detect an associated SSB of the CSI-RS resources in the target cell 131 and determine the first timing based on the associated SSB. In this manner, the timing of the associated SSB and therefore the timing of the CSI-RS from the target cell 131 is determined.

[0050] The first device 110 determines a second timing used by the first device 110 to measure the CSI-RS, at 312. The second timing may be considered as a reference timing used by the first device 110 in measuring the CSI-RS. For example, under the assumption of a single FFT, the second timing may be the timing of a single FFT to be applied to decode the CSI-RS.

[0051] In some demonstrative embodiments, the first device 110 may determine the second timing based on timing information of the serving cell 121. For example, the second timing may be determined based on an SSB of the serving cell 121. If the measurement of the target CSI-RS is an intra-frequency measurement, the second timing may be determined based on an SSB of the serving cell 121.

[0052] In some example embodiments, the first device 110 may determine a reference cell from a set of cells to be measured, including the target cell 131. The second device 120 may configure the first device 110 to measure CSI-RS from a set of cells on the carrier. The first device 110 may then determine a second timing based on timing information of the reference cell. As an example, if the measurement of the target CSI-RS is an inter-frequency measurement, the second timing, i.e., the timing used to measure the CSI-RS resources on the carrier, may be determined based on the timing of the reference cell to be measured, rather than the serving cell 121. For example, the second timing may be determined based on an associated SSB of the reference cell.

[0053] In the case of inter-frequency measurements, any suitable technique may be used to determine the second timing, e.g., the timing of a single FFT under the assumption of a single FFT. As an example, the first device 110 may determine the second timing based on the timing of a cell with the highest signal strength in the set of cells. As another example, the first device 110 may determine the second timing based on the timing of a first cell detected by the first device 110 in the set of cells. As a further example, the first device 110 may determine the second timing based on the timing of a cell with the highest or lowest index in the set of cells. As a further example, the first device 110 may determine the second timing based on the timing of a cell that is aligned with as many other cells as possible. Alternatively, the first device 110 may determine the second timing by applying a timing offset to the timing of the cell such that as many CSI-RS resources as possible are measured with a timing difference within a threshold.

[0054] Continuing with FIG. 3, the first device 110 determines 315 a timing difference between the first timing and the second timing. In some exemplary embodiments, for example, in the case of intra-frequency measurements, the timing difference between the first timing and the second timing may represent a timing difference between the serving cell 121 and the target cell 131. In these exemplary embodiments, the first device 110 determines the timing difference based on an SSB of the serving cell 121 and an associated SSB of the CSI-RS resources in the target cell 131 cell.

[0055] In some other exemplary embodiments, for example, in the case of inter-frequency measurements, the timing difference between the first timing and the second timing may represent a timing difference between the target cell 131 and a reference cell determined from the set of cells to be measured. In these exemplary embodiments, the first device 110 may determine the timing difference based on the associated SSB of the target cell 131 and the SSB of the reference cell.

[0056] The first device 110 transmits 320 information regarding the measurement of the target CSI-RS to the second device 120 based on the timing difference. The particular content of the transmitted information may depend on whether the timing difference requirement is met. For example, the timing difference requirement is met if the timing difference is below a threshold. The threshold may be, for example, a CP, half a CP, or a number of CPs.

[0057] In some exemplary embodiments, the first device 110 may determine, or the second device 120 may instruct the first device 110, whether to perform and report measurements of the target CSI-RS based on whether the timing difference is below a threshold. For example, the first device 110 may perform measurements of the target CSI-RS and report the measurement results only if the timing difference is below a threshold. If the timing difference exceeds the threshold, the first device 110 may not perform measurements of the target CSI-RS and indicate to the second device 120 that the measurement of the target CSI-RS has failed. In other words, the first device 110 shall not measure or report measurements of CSI-RS from cells for which the timing difference requirement is not met. Such exemplary embodiments are described in detail with reference to FIG. 4 and FIG. 5.

[0058] In some exemplary embodiments, the first device 110 may perform, or be instructed by the second device 120 to perform, a measurement of the target CSI-RS and report the measurement result regardless of whether the timing difference exceeds a threshold. In such exemplary embodiments, the first device 110 may further indicate to the second device 120 whether the timing difference exceeds a threshold. Such exemplary embodiments are described in detail with reference to FIG. 6.

[0059] 4 illustrates a flowchart illustrating an example process 400 for processing CSI-RS measurements according to some example embodiments of the present disclosure. The example process 400 may be considered a specific implementation of the process 300. The process 400 includes at least the first device 110, the second device 120, and the third device 130 as shown in FIG. 1. As shown in FIG. 4, in the process 400, the third device 130 may transmit an SSB (e.g., including an associated SSB) and a CSI-RS (e.g., a target CSI-RS) from the target cell 131 to the first device 110.

[0060] As shown, the second device 120 configures 305 the first device 110 to measure a target CSI-RS from a target cell 131 provided by the third device 130. The first device 110 detects 410 an associated SSB 405 for the target CSI-RS to obtain the timing of the target cell 131. In this manner, the first timing of the target CSI-RS is determined to be the timing of the associated SSB, i.e., the timing of the target cell 131.

[0061] The first device 110 determines 412 a second timing to be used by the first device 110 to measure the CSI-RS. The second timing may be determined as described above with respect to operation 312 of FIG. 3. For example, in the case of intra-frequency measurement, the second timing may be determined to be the timing of the serving cell 121, e.g., based on the SSB of the serving cell 121. In the case of inter-frequency measurement, the second timing may be determined to be the timing of a reference cell from the set of cells to be measured. For example, the second timing may be determined based on the SSB of the reference cell.

[0062] The first device 110 determines 415 a timing difference between the first timing and the second timing. The timing difference may be determined as described above with reference to FIG. For example, in the case of intra-frequency measurements, the first device 110 may determine a timing difference based on an associated SSB of the target cell 131 and an SSB of the serving cell 121. In the case of inter-frequency measurements, the first device 110 may determine a timing difference based on an associated SSB of the target cell 131 and an SSB of the reference cell.

[0063] In block 420, the first device 110 determines whether the timing difference is less than a threshold. If the timing difference is less than the threshold, the process 400 proceeds to block 401. As shown, the first device 110 may measure CSI-RS 422 from a target cell 131 provided by the third device 130 (425). In other words, the first device 110 may perform a CSI-RS 422 measurement. The first device 110 then transmits a result of the CSI-RS 422 measurement to the second device 120 in 430. For example, the first device 110 may transmit a measurement report to the second device 120. Thus, the result of the CSI-RS measurement received at the second device may have a qualified accuracy. This may ensure the performance of the CSI-RS measurement.

[0064] If, at block 420, the first device 110 determines that the timing difference exceeds a threshold, the process 400 proceeds to block 402. As shown, the first device 110 may transmit an indication to the second device 120 that it is unable to measure, or unable to measure with adequate accuracy, CSI-RS from the target cell 131 due to the timing difference exceeding a threshold (435). For illustrative purposes only and without limiting the scope of this discussion, such an indication may be referred to hereinafter as a "failure indication." The failure indication may indicate the second device 120 of failure in measuring CSI-RS from the target cell 131. After receiving the failure indication, the second device 1120 may deconfigure CSI-RS measurements on the target cell 131. For example, the second device 120 may transmit an indication to the first device 110 to disable measurement of CSI-RS from the target cell 131 (also referred to as a "configuration indication") at 440.

[0065] FIG. 5 shows a flowchart illustrating an example process 500 for processing CSI-RS measurements according to some embodiments of the present disclosure. The example process 500 may be considered as a specific implementation of the process 300. The process 500 includes at least the first device 110, the second device 120, and the third device 130 as shown in FIG. 1. As shown in FIG. 5, in the process 500, the third device 130 may transmit an SSB (e.g., including an associated SSB) and a CSI-RS (e.g., a target CSI-RS) from the target cell 131 to the first device 110. Only the differences between the process 400 and the process 500 will be described.

[0066] If, at block 420, the first device 110 determines that the timing difference exceeds a threshold, the process 500 proceeds to block 502. The first device 110 may continue tracking the timing difference instead of immediately indicating a failure of the CSI-RS measurement to the second device 120. As shown in FIG. 5, at block 502, the first device 110 may continue tracking the timing of the target cell 131 for a period of time. For example, a timer may be started upon determining that the timing difference exceeds a threshold. If the timing difference falls below the threshold within the time period or before the timer expires, the first device 110 may perform a measurement of the CSI-RS from the target cell 131 and report the measurement results to the second device 120. If the timing difference still exceeds the threshold by the end of the time period, the first device 110 may indicate to the second device 120 that the target CSI-RS and / or the target cell 131 cannot be measured or cannot be measured with adequate accuracy.

[0067] As shown, the first device 110 may detect an associated SSB 530 from the target cell 131 to obtain an updated first timing (535). In other words, an updated timing of the target cell 131 may be obtained. Thus, the first device 110 may update a timing difference based on the updated first timing and the second timing. In block 540, the first device 110 may determine whether the updated timing difference is below a threshold. If the updated timing difference is below the threshold within the time period or before the timer expires, the process 500 proceeds to block 503. The first device 110 may measure the CSI-RS from the target cell 131 in 545. In other words, the first device 110 may perform a measurement of the CSI-RS. The first device 110 may then transmit the result of the CSI-RS measurement to the second device 120 (550). For example, the first device 110 may transmit a measurement report to the second device 120. Thus, the result of the CSI-RS measurement received at the second device 120 may have a qualified accuracy. This may ensure the performance of the CSI-RS measurement.

[0068] If, at block 540, the first device 110 determines that the timing difference still exceeds the threshold by the end of the time period, the first device 110 may transmit (555) a failure indication to the second device 120 that it is unable to measure CSI-RS from the target cell 131 or is unable to measure with adequate accuracy because the timing difference exceeds the threshold. The failure indication may indicate the second device 120 of failure in measuring CSI-RS from the target cell 131. Although not shown, the second device 120 may deconfigure CSI-RS measurements on the target cell 131 after receiving the failure indication. For example, the second device 120 may transmit a configuration indication to the first device 110 to disable measurement of CSI-RS from the target cell 131.

[0069] In the above exemplary embodiment described with reference to Figures 4 and 5, the principle is to measure the configured CSI-RS from the target cell based on the timing difference. For example, in case of intra-frequency measurement, based on the timing difference between the serving cell and the target cell, the first device (e.g., UE) is only required to measure the configured CSI-RS for L3 if the timing difference is below a defined threshold. Otherwise, the first device does not need to measure the CSI-RS for L3 from the target cell. The first device shall not report measurements of the L3 CSI-RS from cells for which the timing difference requirement is not met.

[0070] In such an exemplary embodiment, the accuracy of the reported result of the CSI-RS measurement can be guaranteed. When the timing difference is large, unnecessary efforts for CSI-RS measurement can be avoided at the first device (e.g., UE side). Furthermore, an indication to the second device (e.g., network device) can help the second device understand the issue and not configure measurements on the target cell.

[0071] FIG. 6 shows a flowchart illustrating an example process 600 for processing CSI-RS measurements according to some embodiments of the present disclosure. The example process 600 may be considered as a specific implementation of the process 300. The process 600 includes at least the first device 110, the second device 120, and the third device 130 as shown in FIG. 1. As shown in FIG. 6, in the process 600, the third device 130 may transmit an SSB (e.g., including an associated SSB) and a CSI-RS (e.g., a target CSI-RS) from the target cell 131 to the first device 110. Only the differences between the process 400 and the process 600 will be described.

[0072] In block 420, the first device 110 determines whether the timing difference is less than a threshold. The process 600 then proceeds to block 601. As shown, the first device 110 may measure the CSI-RS 620 from the target cell 131 provided by the third device 130 (625). In other words, the first device 110 may perform a CSI-RS 620 measurement. The first device 110 then transmits, in 630, a result of the CSI-RS 620 measurement and an indication of whether the timing difference is below a threshold (also referred to as a "timing indication") to the second device 120. For example, the first device 110 may transmit a measurement report to the second device 120. The first device 110 may add a specific value to the measurement report. The specific value may implicitly indicate that the CSI-RS is measured without meeting the timing difference threshold or with a problematic timing difference. Alternatively, the first device 110 may transmit the measurement result and further transmit an indication that the CSI-RS is measured without meeting the timing difference threshold or with a problematic timing difference. In this way, the second device (e.g., a network device) can know whether the reported result is accurate or not. In some example embodiments, if the timing indication indicates that the timing difference exceeds the threshold, the second device 120 may deconfigure the CSI-RS measurement on the target cell 131. For example, the second device 120 may transmit a configuration indication to the first device 110 to disable the measurement of CSI-RS from the target cell 131.

[0073] In the example processes 400, 500, and 600, the second device 120 and the third device 130 are shown separately. In some example embodiments, the second device 120 and the third device 130 may be the same, and the operations described with respect to the second device 120 may be performed in a serving cell, and the operations described with respect to the third device 130 may be performed in another cell.

[0074] FIG. 7 shows a flowchart of an example method 700 implemented in a first device 110 according to some example embodiments of the present disclosure. For illustrative purposes, the method 700 is described from the perspective of the first device 110 with respect to FIG. 1. In block 710, the first device 110 determines a first timing of a channel state information reference signal from a target cell. The first device 110 is configured by the second device 120 to measure the channel state information reference signal. In some example embodiments, the first device 110 may detect a synchronization signal block of the target cell associated with the channel state information reference signal and determine the first timing based on the synchronization signal block.

[0075] In block 720, the first device 110 determines a second timing used by the first device 110 to measure the channel state information reference signal. In some exemplary embodiments, the first device 110 may determine the second timing based on timing information of the serving cell 121 provided by the second device 120.

[0076] In some exemplary embodiments, the first device 110 may determine a cell from a set of cells that comprises the target cell. The first device 100 is configured to measure channel state information reference signals from the set of cells. The first device 110 may determine a second timing based on timing information of the determined cell.

[0077] In block 730, the first device 110 determines a timing difference between the first timing and the second timing. In block 740, based on the timing difference, the first device 110 transmits information regarding the measurement of the channel state information reference signal to the second device 120.

[0078] In some demonstrative embodiments, if the timing difference is below a threshold, the first device 110 may perform a measurement of the channel state information reference signal and transmit the result of the measurement to the second device 120.

[0079] In some demonstrative embodiments, if the timing difference exceeds a threshold, the first device 110 may transmit an indication that the timing difference exceeds a threshold to the second device 120. In some demonstrative embodiments, the first device 110 may receive a configuration indication from the second device 120 to disable measurement of the channel state information reference signal.

[0080] In some exemplary embodiments, if the timing difference exceeds a threshold, the first device 110 may obtain an updated first timing from the target cell and may update the timing difference based on the updated first timing and the second timing. If the updated timing difference falls below the threshold within the time period, the first device 110 may perform a measurement of the channel state information reference signal and transmit a result of the measurement to the second device 120. In some exemplary embodiments, if the updated timing difference exceeds a threshold for the time period, the first device 110 may transmit an indication to the second device 120 that the time difference exceeds the threshold. In some exemplary embodiments, the first device 110 may further receive a configuration indication from the second device 120 for disabling measurement of the channel state information reference signal.

[0081] In some exemplary embodiments, the first device 110 may perform a measurement of the channel state information reference signal and may transmit a result of the measurement and a timing indication of whether the timing difference exceeds a threshold to the second device 120. In some exemplary embodiments, the timing indication may indicate a timing difference that exceeds a threshold. The first device 110 may receive a configuration indication from the second device 120 to disable measurement of the channel state information reference signal.

[0082] 8 shows a flowchart of an example method 800 implemented in a second device according to some example embodiments of the present disclosure. For purposes of explanation, the method 800 is described from the perspective of the second device 120 with respect to FIG.

[0083] In block 810, the second device 120 configures the first device 110 to measure a channel state information reference signal from a target cell. In block 820, the second device 120 receives information from the first device 110 regarding the measurement of the channel state information reference signal based on a timing difference between a first timing of the channel state information reference signal and a second timing used by the first device 110 to measure the channel state information reference signal.

[0084] In some demonstrative embodiments, the second device 120 may receive the results of the measurement from the first device 110 .

[0085] In some demonstrative embodiments, the second device 120 may receive an indication from the first device 110 that the timing difference exceeds a threshold. In some demonstrative embodiments, the second device 120 may send a configuration indication to the first device 110 to disable measurement of the channel state information reference signal.

[0086] In some demonstrative embodiments, the second device 120 may receive from the first device 110 the results of the measurement and a timing indication of whether the timing difference exceeds a threshold.

[0087] In some demonstrative embodiments, if the timing indication indicates a timing difference exceeding a threshold, the second device 120 may send a configuration indication to the first device 110 to disable measurement of the channel state information reference signal.

[0088] In some demonstrative embodiments, a first apparatus (e.g., first device 110) capable of performing any of methods 700 may comprise means for performing each operation of method 700. The means may be embodied in any suitable form. For example, the means may be embodied in a circuit or a software module. The first apparatus may be implemented as or included within first device 110.

[0089] In some demonstrative embodiments, a first apparatus comprises means for determining a first timing of a channel state information reference signal from a target cell, the first apparatus is configured by a second apparatus to measure the channel state information reference signal, and the first device comprises means for determining a second timing used by the first apparatus to measure the channel state information reference signal, means for determining a timing difference between the first timing and the second timing, and means for transmitting information regarding the measurement of the channel state information reference signal to the second apparatus based on the timing difference.

[0090] In some demonstrative embodiments, the means for determining the first timing comprises means for detecting a synchronization signal block of a target cell associated with the channel state information reference signal and means for determining the first timing based on the synchronization signal block.

[0091] In some exemplary embodiments, the means for determining the second timing comprises means for determining the second timing based on a timing of a serving cell provided by the second device.

[0092] In some demonstrative embodiments, the means for determining the second timing comprises means for determining a cell from a set of cells comprising the target cell, where the first device is configured to measure channel state information reference signals from the set of cells, and means for determining the second timing based on timing information of the determined cell.

[0093] In some exemplary embodiments, the means for transmitting information comprises: means for performing a measurement of the channel state information reference signal in response to determining that the timing difference is less than or equal to a threshold; and transmitting means for transmitting the measurement result to the second device.

[0094] In some exemplary embodiments, the means for transmitting comprises means for transmitting an indication that the timing difference exceeds the threshold to the second device according to a determination that the timing difference exceeds the threshold. In some exemplary embodiments, the first device further comprises means for receiving from the second device a configuration indication to disable measurement of the channel state information reference signal.

[0095] In some exemplary embodiments, the means for transmitting information comprises means for obtaining an updated first timing from the target cell in accordance with a determination that the timing difference exceeds a threshold, means for updating the timing difference based on the updated first timing and the second timing, means for performing a measurement of a channel state information reference signal in accordance with a determination that the updated timing difference is below a threshold for a time period, and means for transmitting a result of the measurement to the second device. In some exemplary embodiments, the first device further comprises means for transmitting an indication that the time difference exceeds a threshold to the second device in accordance with a determination that the updated timing difference exceeds a threshold for the time period. In some exemplary embodiments, the first device further comprises means for receiving a configuration indication from the second device to disable measurement of the channel state information reference signal.

[0096] In some exemplary embodiments, the means for transmitting information comprises means for performing a measurement of the channel state information reference signal and means for transmitting a result of the measurement and a timing indication of whether the timing difference exceeds a threshold to the second device. In some exemplary embodiments, the timing indication may indicate a timing difference that exceeds the threshold. The first device further comprises means for receiving a configuration indication from the second device to disable the measurement of the channel state information reference signal.

[0097] In some exemplary embodiments, the second device comprises means for configuring the first device to measure a channel state information reference signal from the target cell, and means for receiving from the first device information regarding the measurement of the channel state information reference signal based on a timing difference between a first timing of the channel state information reference signal and a second timing used by the first device to measure the channel state information reference signal.

[0098] In some exemplary embodiments, the first means comprises means for receiving the measurement from the first device.

[0099] In some embodiments, the means for receiving the information comprises means for receiving an indication from the first device that the timing difference exceeds a threshold. In some exemplary embodiments, the second device further comprises means for transmitting to the first device a configuration indication to disable measurement of a channel state information reference signal.

[0100] In some exemplary embodiments, the means for receiving information comprises means for receiving from the first device a result of the measurement and a timing indication of whether the timing difference exceeds a threshold. In some exemplary embodiments, the second device further comprises means for transmitting a configuration indication to the first device to disable measurement of the channel state information reference signal according to a determination that the timing indication indicates a timing difference that exceeds the threshold.

[0101] 9 is a simplified block diagram of a device 900 suitable for implementing embodiments of the present disclosure. The device 900 may be provided to implement a communication device, e.g., the first device 110, the second device 120, and the third device 130, as shown in FIG. 1. As shown, the device 900 includes one or more processors 910, one or more memories 920 coupled to the processor 910, and one or more communication modules 940 (e.g., a transmitter and / or a receiver) coupled to the processor 910.

[0102] The communication module 940 is for bidirectional communication. The communication module 940 has at least one antenna to facilitate communication. The communication interface may represent any interface necessary for communication with other network elements.

[0103] The processor 910 may be of any type suitable for a local technology network and may include, by way of non-limiting examples, one or more of a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor architecture. The device 1200 may have multiple processors, such as application specific integrated circuit chips time-slaved to a clock that synchronizes the main processor.

[0104] The memory 920 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) 924, electrically programmable read only Memory (EPROM), flash memory, hard disks, compact discs (CDs), digital video disks (DVDs), and other magnetic and / or optical storage devices. Examples of volatile memories include, but are not limited to, Random Access Memory (RAM) 922 and other volatile memories that do not last during a power down period.

[0105] The computer program 930 includes computer executable instructions that are executed by the associated processor 910. The program 930 may be stored in the ROM 920. The processor 910 can load the program 930 into the RAM 920 to perform any suitable operations and processes.

[0106] The embodiment of the present disclosure may be implemented by means of a program 930 such that the device 900 can execute any process of the present disclosure described in relation to Figures 7 to 8. The embodiment of the present disclosure may also be implemented by hardware or a combination of software and hardware.

[0107] In some embodiments, the program 930 may be tangibly included in a computer-readable medium that may be included in the device 900 (such as memory 920) or other storage device accessible by the device 900. The device 900 may load the program 930 from the computer-readable medium into RAM 922 for execution. The computer-readable medium may include any type of tangible non-volatile memory, such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc. Figure 10 shows an example of a computer-readable medium 1000 in the form of a CD or DVD. The computer-readable medium has the program 930 stored thereon.

[0108] Generally, various embodiments of the present disclosure may be implemented in hardware or dedicated circuits, software, logic, or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software that may be executed by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of the present disclosure are illustrated and described as block diagrams, flow charts, or using some other pictorial representations, it should be understood that the blocks, apparatus, systems, techniques, or methods described herein may be implemented in, by way of non-limiting examples, hardware, software, firmware, dedicated circuits or logic, general-purpose hardware or controller, or other computing device, or any combination thereof.

[0109] The present 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 included in program modules, that execute on a device on a target real or virtual processor to perform the method 700 or 800 described above with reference to Figures 7-8. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split among program modules as desired in various aspects. Machine-executable instructions for program modules may be executed in local or distributed devices. In a distributed device, program modules may be located in both local and remote storage media.

[0110] The program codes for carrying out the methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, a special purpose computer, or other programmable data processing apparatus, such that when executed by the processor or controller, the program codes cause the processor or controller to implement the functions / operations specified in the flowcharts and / or block diagrams. The program codes may be executed entirely on the machine, partially on the machine, as a stand-alone software package, partially on the machine, partially on a remote machine, or entirely on a remote machine or server.

[0111] In the context of the present disclosure, computer program code or associated 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.

[0112] The computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. The computer-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the above. More specific examples of the computer-readable storage medium include an electrical connection with one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0113] Furthermore, although operations are depicted in a particular order, this should not be understood as requiring such operations to be performed in the particular order depicted, or in sequential order, or that all depicted operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Similarly, while some specific implementation details are included in the above description, these should not be construed as limitations on the scope of the disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may be implemented in multiple embodiments separately or in any suitable combination.

[0114] Although the present disclosure has been described in language specific to structural features and / or methodological acts, it is to be understood that the present disclosure, as defined in the appended claims, is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A first device comprising at least one processor and at least one memory containing computer program code, the at least one memory and the computer program code comprising: and, using the at least one processor, causing the first device to at least: determining a first timing of a channel state information reference signal from a target cell, where the first device is configured by a second device to measure the channel state information reference signal; determining a second timing used by the first device to measure the channel state information reference signal; determining a timing difference between the first timing and the second timing; and causing the second device to transmit information regarding the measurement of the channel state information reference signal based on the timing difference. First device.

2. The at least one memory and the computer program code are configured to cause the first device, using the at least one processor, to: detecting a synchronization signal block of the target cell associated with the channel state information reference signal; determining the first timing based on the synchronization signal block; By configured to determine the first timing; The first device of claim 1 .

3. The at least one memory and the computer program code are configured to cause the first device, using the at least one processor, to: and determining the second timing based on timing information of a serving cell provided by the second device. A first device according to claim 1 or 2.

4. The at least one memory and the computer program code are configured to cause the first device, using the at least one processor, to: determining a cell from a set of cells that comprises the target cell, the first device is configured to measure channel state information reference signals from the set of cells; determining the second timing based on the determined cell timing information. A first device according to claim 1 or 2.

5. The at least one memory and the computer program code are configured to cause the first device, using the at least one processor, to: performing the measurement of the channel state information reference signal in response to determining that the timing difference is below a threshold; transmitting results of said measurements to said second device; configured to cause the information to be transmitted by The first device of claim 1 .

6. The at least one memory and the computer program code are configured to cause the first device, using the at least one processor, to: and configured, in response to a determination that the timing difference exceeds a threshold, to cause the information to be transmitted by transmitting an indication to the second device that the timing difference exceeds the threshold. The first device of claim 1 .

7. The at least one memory and the computer program code are configured to cause the first device, using the at least one processor, to: obtaining an updated first timing from the target cell in response to a determination that the timing difference exceeds a threshold; updating the timing difference based on the updated first timing and the second timing; performing the measurement of the channel state information reference signal in accordance with a determination that the updated timing difference falls below the threshold within a time period; transmitting results of said measurements to said second device; configured to cause the information to be transmitted by The first device of claim 1 .

8. The at least one memory and the computer program code are transmitted to the first device using the at least one processor, configured to, in response to a determination that the updated timing difference exceeds the threshold for the time period, cause a second device to transmit an indication that the time difference exceeds the threshold. The first device according to claim 7.

9. The at least one memory and the computer program code, using the at least one processor, further cause the first device to: and configured to receive, from the second device, a configuration indication to disable the measurement of the channel state information reference signal. A first device according to claim 6 or 8.

10. The at least one memory and the computer program code are configured to cause the first device, using the at least one processor, to: performing said measurement of said channel state information reference signal; transmitting to the second device a result of the measurement and a timing indication of whether the timing difference exceeds a threshold. configured to cause the information to be transmitted; The first device of claim 1 .

11. the timing indication being indicative of the timing difference exceeding the threshold; 11. The first device of claim 10, wherein the at least one memory and the computer program code, using the at least one processor, are further configured to cause the first device to receive from the second device a configuration indication to disable the measurement of the channel state information reference signal.

12. a second device comprising at least one processor and at least one memory containing computer program code, The at least one memory and the computer program code, using the at least one processor, configure the first device to cause the second device to measure a channel state information reference signal from a target cell; and configured to receive, from a first device, information regarding a measurement of the channel state information reference signal based on a timing difference between a first timing of the channel state information reference signal and a second timing used by the first device to measure the channel state information reference signal. Second device.

13. The second device of claim 12, wherein the at least one memory and the computer program code are configured, using the at least one processor, to cause the second device to receive the information by receiving results of the measurement from the first device.

14. 13. The second device of claim 12, wherein the at least one memory and the computer program code are configured, using the at least one processor, to cause the second device to receive the information by receiving an indication from the first device that the timing difference exceeds a threshold.

15. 15. The second device of claim 14, wherein the at least one memory and the computer program code are further configured, with the at least one processor, to cause the second device to send to the first device a configuration indication to disable the measurement of the channel state information reference signal.

16. 13. The second device of claim 12, wherein the at least one memory and the computer program code are configured, using the at least one processor, to cause the second device to receive from the first device a result of the measurement and a timing indication of whether the timing difference exceeds a threshold.

17. 17. The second device of claim 16, wherein the at least one memory and the computer program code are configured, using the at least one processor, to cause the second device to transmit a configuration indication to the first device to disable the measurement of the channel state information reference signal pursuant to a determination that the timing indication indicates the timing difference exceeding the threshold.

18. In the first device, determining a first timing of a channel state information reference signal from a target cell, the first device being configured by a second device to measure the channel state information reference signal; determining a second timing used by the first device to measure the channel state information reference signal; determining a timing difference between the first timing and the second timing; transmitting, to the second device, information regarding the measurement of the channel state information reference signal based on a timing difference; A method comprising:

19. 20. The device of claim 18, wherein determining the first timing comprises: detecting a synchronization signal block of the target cell associated with the channel state information reference signal; and determining the first timing based on the synchronization signal block.

20. The method of claim 18 or 19, wherein determining the second timing comprises determining the second timing based on timing information of a serving cell provided by the second device.

21. The step of determining the second timing includes: determining a cell from a set of cells comprising the target cell, the first device being configured to measure channel state information reference signals from the set of cells; determining the second timing based on the determined cell timing information; 20. The method of claim 18 or 19, comprising:

22. The step of transmitting the information includes: performing the measurement of the channel state information reference signal in response to determining that the timing difference is below a threshold; transmitting results of the measurements to the second device; 20. The method of claim 18, comprising:

23. The step of transmitting the information includes: In response to determining that the timing difference exceeds a threshold, transmitting an indication to the second device that the timing difference exceeds the threshold.

20. The method of claim 18, comprising:

24. The step of transmitting the information includes: obtaining an updated first timing from the target cell in response to determining that the timing difference exceeds a threshold; updating the timing difference based on the updated first timing and the second timing; performing the measurement of the channel state information reference signal in accordance with a determination that the updated timing difference falls below the threshold within a time period; transmitting results of the measurements to the second device; 20. The method of claim 18, comprising:

25. 25. The method of claim 24, further comprising: pursuant to a determination that the updated timing difference exceeds the threshold for the time period, transmitting an indication to the second device that the time difference exceeds the threshold.

26. The method of claim 23 or 25, further comprising receiving from the second device a configuration indication to disable the measuring of the channel state information reference signal.

27. The step of transmitting the information includes: performing said measurement of said channel state information reference signal; transmitting to the second device a result of the measurement and a timing indication of whether the timing difference exceeds a threshold; 20. The method of claim 18, comprising:

28. the timing indication being indicative of the timing difference exceeding the threshold; The method further comprises receiving, from the second device, a configuration indication to disable the measurement of the channel state information reference signal.

28. The method of claim 27.

29. configuring, at the second device, the first device to measure a channel state information reference signal from the target cell; receiving from the first device information regarding a measurement of the channel state information reference signal based on a timing difference between a first timing of the channel state information reference signal and a second timing used by the first device to measure the channel state information reference signal; The method includes:

30. 30. The method of claim 29, wherein the step of receiving information comprises the step of receiving a result of the measurement from the first device.

31. 30. The method of claim 29, wherein receiving the information comprises receiving an indication from the first device that the timing difference exceeds a threshold.

32. 32. The method of claim 31, further comprising the step of transmitting to the first device a configuration indication to disable the measuring of the channel state information reference signal.

33. The step of receiving information includes receiving, from the first device, a result of the measurement, and 30. The method of claim 29, comprising receiving a timing indication of whether the timing difference exceeds a threshold.

34. 34. The method of claim 33, further comprising: transmitting a configuration indication to the first device to disable the measuring of the channel state information reference signal in response to a determination that the timing indication indicates a timing difference that exceeds the threshold.

35. means for determining a first timing of a channel state information reference signal from a target cell, the first device being configured by a second device to measure said channel state information reference signal; means for determining a second timing used by the first device to measure the channel state information reference signal; means for determining a timing difference between the first timing and the second timing; means for transmitting information regarding the measurement of the channel state information reference signal to the second device based on the timing difference; A first device comprising:

36. means for configuring the first device to measure a channel state information reference signal from a target cell; means for receiving from the first device information regarding a measurement of the channel state information reference signal based on a timing difference between a first timing of the channel state information reference signal and a second timing used by the first device to measure the channel state information reference signal; A second device comprising:

37. A computer readable medium comprising program instructions for causing an apparatus to carry out at least the method of any one of claims 18 to 28 or claims 29 to 34.

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