Channel state information reporting for downlink control channel transmission

Abstract

Example embodiments of the present disclosure are related to channel state information (CSI) reporting for downlink control channel transmission A method includes determining channel state information associated with a downlink control channel based at least in part on measurement information about a channel state information reference signal from a network device; and transmitting, by a first apparatus and to a network device the network device, a channel state information report at least including the channel state information associated with the downlink control channel. By this way, the demodulation and reception performance of the downlink control channel is improved.

Description

CHANNEL STATE INFORMATION REPORTING FOR DOWNLINK CONTROL CHANNEL TRANSMISSIONCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority from, and the benefit of, US Provisional Application No. 63 / 716402, filed November 5, 2024, which is hereby incorporated by reference in its entirety.FIELD

[0002] Various example embodiments of the present disclosure generally relate to the field of telecommunication and in particular, to methods, devices, apparatuses and computer readable storage medium for channel state information (CSI) reporting for downlink control channel transmission.BACKGROUND

[0003] In telecommunication systems, CSI is estimated and reported for the purpose of downlink transmission, for example, transmission by a network device (e.g., gNB) and reception by a terminal device(s) (e.g., user equipment, UE). Currently, the CSI is reported for a downlink data channel, e.g., the physical downlink shared channel (PDSCH) for multiple input multiple output (MIMO).SUMMARY

[0004] In a first aspect of the present disclosure, there is provided a first apparatus. The first apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus at least to: determine channel state information associated with a downlink control channel based at least in part on measurement information about a channel state information reference signal from a network device; and transmit, to the network device, a channel state information report at least comprising the channel state information associated with the downlink control channel.

[0005] In a second aspect of the present disclosure, there is provided a second apparatus. The second apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the second apparatus at least to: receive, from a terminal device, a channel state information report at least comprising channel state information associated with a downlink control channel; and determine a transmission scheme for a transmission of the downlink control channel to theterminal device based on the channel state information associated with the downlink control channel.

[0006] In a third aspect of the present disclosure, there is provided a method. The method comprises: determining channel state information associated with a downlink control channel based at least in part on measurement information about a channel state information reference signal from a network device; and transmitting, to the network device, a channel state information report at least comprising the channel state information associated with the downlink control channel.

[0007] In a fourth aspect of the present disclosure, there is provided a method. The method comprises: receiving, from a terminal device, a channel state information report at least comprising channel state information associated with a downlink control channel; and determining a transmission scheme for a transmission of the downlink control channel to the terminal device based on the channel state information associated with the downlink control channel.

[0008] In a fifth aspect of the present disclosure, there is provided a first apparatus. The first apparatus comprises means for determining channel state information associated with a downlink control channel based at least in part on measurement information about a channel state information reference signal from a network device; and means for transmitting, to the network device, a channel state information report at least comprising the channel state information associated with the downlink control channel.

[0009] In a sixth aspect of the present disclosure, there is provided a second apparatus. The second apparatus comprises means for receiving, from a terminal device, a channel state information report at least comprising channel state information associated with a downlink control channel; and means for determining a transmission scheme for a transmission of the downlink control channel to the terminal device based on the channel state information associated with the downlink control channel.

[0010] In a seventh aspect of the present disclosure, there is provided a computer readable medium. The computer readable medium comprises instructions stored thereon for causing an apparatus to perform at least the method according to the third aspect.

[0011] In an eighth aspect of the present disclosure, there is provided a computer readable medium. The computer readable medium comprises instructions stored thereon for causing an apparatus to perform at least the method according to the fourth aspect.

[0012] It is to be understood that the Summary section is not intended to identify key or essential features of 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 becomeeasily comprehensible through the following description.BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Some example embodiments will now be described with reference to the accompanying drawings, where:

[0014] FIG. 1 illustrates an example communication environment in which example embodiments of the present disclosure can be implemented;

[0015] FIG. 2 illustrates a signaling flow for CSI reporting in accordance with some example embodiments of the present disclosure;

[0016] FIG. 3 illustrates a specific signaling flow for CSI reporting in accordance with some example embodiments of the present disclosure;

[0017] FIG. 4 illustrates a flowchart of a method implemented at a terminal device in accordance with some example embodiments of the present disclosure;

[0018] FIG. 5 illustrates a flowchart of a method implemented at a network device in accordance with some other example embodiments of the present disclosure;

[0019] FIG. 6 illustrates a simplified block diagram of a device that is suitable for implementing example embodiments of the present disclosure; and

[0020] FIG. 7 illustrates a block diagram of an example computer readable medium in accordance with some example embodiments of the present disclosure.

[0021] Throughout the drawings, the same or similar reference numerals represent the same or similar element.DETAILED DESCRIPTION

[0022] Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. Embodiments described herein can be implemented in various manners other than the ones described below.

[0023] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

[0024] References in the present disclosure to “one embodiment,” “an embodiment,” “an example embodiment,” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are notnecessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

[0025] It shall be understood that although the terms “first,” “second,”... , etc. in front of noun(s) and the like may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another and they do not limit the order of the noun(s). For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and / or” includes any and all combinations of one or more of the listed terms.

[0026] As used herein, “at least one of the following: ” and “at least one of ” and similar wording, where the list of two or more elements are joined by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

[0027] As used herein, unless stated explicitly, performing a step “in response to A” does not indicate that the step is performed immediately after “A” occurs and one or more intervening steps may be included.

[0028] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example 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 will be further understood that the terms “comprises”, “comprising”, “has”, “having”, “includes” and / or “including”, when used herein, specify the presence of stated features, elements, and / or components etc., but do not preclude the presence or addition of one or more other features, elements, components and / or combinations thereof.

[0029] As used in this application, the term “circuitry” may refer to one or more or all of the following:(a) hardware-only circuit implementations (such as implementations in only analog and / or digital circuitry) and(b) combinations of hardware circuits and software, such as (as applicable):(i) a combination of analog and / or digital hardware circuit(s) with software / firmware and(ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to causean apparatus, such as a mobile phone or server, to perform various functions) and(c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

[0030] This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

[0031] As used herein, the term “communication network” refers to a network following any suitable communication standards, such as New Radio (NR), Long Term Evolution (LTE), LTE- Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), High-Speed Packet Access (HSPA), Narrow Band Internet of Things (NB-IoT) and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G), the second generation (2G), 2.5G, 2.75G, the third generation (3G), the fourth generation (4G), 4.5G, the fifth generation (5G), the sixth generation (6G) communication protocols, and / or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

[0032] As used herein, the term “network device” refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. The network device may refer to a base station (BS) or an access point (AP), for example, a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), an NR NB (also referred to as a gNB), a Remote Radio Unit (RRU), a radio header (RH), a remote radio head (RRH), a relay, an Integrated Access and Backhaul (IAB) node, a low power node such as a femto, a pico, a non-terrestrial network (NTN) or non-ground network device such as a satellitenetwork device, a low earth orbit (LEO) satellite and a geosynchronous earth orbit (GEO) satellite, an aircraft network device, and so forth, depending on the applied terminology and technology. In some example embodiments, radio access network (RAN) split architecture comprises a Centralized Unit (CU) and a Distributed Unit (DU) at an IAB donor node. An IAB node comprises a Mobile Terminal (IAB-MT) part that behaves like a UE toward the parent node, and a DU part of an IAB node behaves like a base station toward the next-hop IAB node.

[0033] The term “terminal device” refers to any end device that may be capable of wireless communication. By way of example rather than limitation, a terminal device may also be referred to as a communication device, user equipment (UE), a Subscriber Station (SS), a Portable Subscriber Station, a Mobile Station (MS), or an Access Terminal (AT). The terminal device may include, but not limited to, a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones, a tablet, a wearable terminal device, a personal digital assistant (PDA), portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), USB dongles, smart devices, wireless customer-premises equipment (CPE), an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and / or other wireless devices operating in an industrial and / or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and / or industrial wireless networks, and the like. The terminal device may also correspond to a Mobile Termination (MT) part of an IAB node (e.g., a relay node). In the following description, the terms “terminal device”, “communication device”, “terminal”, “user equipment” and “UE” may be used interchangeably.

[0034] As used herein, the term “resource,” “transmission resource,” “resource block,” “physical resource block” (PRB), “uplink resource,” or “downlink resource” may refer to any resource for performing a communication, for example, a communication between a terminal device and a network device, such as a resource in time domain, a resource in frequency domain, a resource in space domain, a resource in code domain, or any other combination of the time, frequency, space and / or code domain resource enabling a communication, and the like. In the following, unless explicitly stated, a resource in both frequency domain and time domain will be used as an example of a transmission resource for describing some example embodiments of the present disclosure. It is noted that exampleembodiments of the present disclosure are equally applicable to other resources in other domains.

[0035] FIG. 1 illustrates a schematic diagram of an example communication environment 100 in which example embodiments of the present disclosure can be implemented. In the communication environment 100, a plurality of communication devices, including a terminal device 110 and a network device 120, communicate with each other.

[0036] In the example of FIG. 1, the terminal device 110 may be a UE and the network device 120 may be a base station serving the UE. The serving area of the network device 120 may be called a cell 102. The network device 120 is operating in a radio access network (RAN) and thus is also referred to as a RAN network device.

[0037] In some example embodiments, the RAN architecture will include a centralized part, or central unit (CU), and a distributed part, or distributed unit (DU). The CU and the DU will be connected to one another by a so-called Fl interface. In some example embodiments, the CU may be split into a CU-UP (central unit-user plane) and a CU-CP (central unit-control plane). The CU-UP and the CU-CP will be connected to one another by a so-called El interface, and the Fl interface will be split between Fl-c and Fl-u interfaces for the control and user planes, respectively.

[0038] It is to be understood that the number of devices and their connections shown in FIG. 1 are only for the purpose of illustration without suggesting any limitation. The communication environment 100 may include any suitable number of devices configured to implementing example embodiments of the present disclosure. Although not shown, it would be appreciated that one or more additional devices may be located in the cell 102, and one or more additional cells may be deployed in the communication environment 100. It is noted that although illustrated as a network device, the network device 120 may be another device than a network device. Although illustrated as a terminal device, the terminal device 110 may be another device than a terminal device.

[0039] In the following, for the purpose of illustration, some example embodiments are described with the terminal device 110 operating as a UE and the network device 120 operating as a base station, e.g., gNB. However, in some example embodiments, operations described in connection with a terminal device may be implemented at a network device or other device, and operations described in connection with a network device may be implemented at a terminal device or other device.

[0040] In some example embodiments, a communication direction from the network device 120 to the terminal device 110 is referred to as a downlink (DL), while a communication direction from the terminal device 110 to the network device 120 is referredto as an uplink (UL). In DL, the network device 120 is a transmitting (TX) device (or a transmitter) and the terminal device 110 is a receiving (RX) device (or a receiver). In UL, the terminal device 110 is a TX device (or a transmitter) and the network device 120 is a RX device (or a receiver).

[0041] Communications in the communication environment 100 may be implemented according to any proper communication protocol(s), comprising, but not limited to, cellular communication protocols of the first generation (1G), the second generation (2G), the third generation (3G), the fourth generation (4G), the fifth generation (5G), the sixth generation (6G), and the like, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and / or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising 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 Multiple (OFDM), Discrete Fourier Transform spread OFDM (DFT-s-OFDM) and / or any other technologies currently known or to be developed in the future.

[0042] Currently, CSI is estimated and reported for the purpose of physical downlink shared channel (PDSCH) transmission, which is, for example, a transmission from the network device and reception by the terminal device. PDSCH is scheduled by the network device using downlink control information (DCI) transmitted on a downlink control channel (e.g., the physical downlink control channel, PDCCH). When applying CSLRS (CSL reference signal)-based precoding for the PDSCH transmission, e.g. using Type I or Type II CSI codebook, the network device may apply a precoder that is determined according to a precoding matrix indicator (PMI) in the CSI feedback provided by the terminal device to the network device.

[0043] A CSI report may contain Part 1 and Part 2, which may be defined as including various components of channel state information. In some examples, the CSI report may be classified as Type I and Type II. Depending on the types of the CSI report, the report formats and the components included in the different parts of the CSI report may be varied.

[0044] In some examples, for a Type I CSI report, Part 1 may contain Rank Indicator (RI) (if reported), Channel Resource Indicator (CRI) (if reported), and Channel Quality Indicator (CQI) for the first codeword; and Part 2 may contain PMI and may contain the Channel Quality Indicator (CQI) for the second codeword when RI>4.

[0045] In some examples, for a Type II CSI report, Part 1 may have a fixed payload sizeand contain RI, CQI, and an indication of the number of non-zero wideband amplitude coefficients per layer for the Type II CSI. Part 2 may contain the PMI of the Type II CSI. In reporting, the fields of Part 1 may be separately encoded, and Part 1 and Part 2 may be separately encoded. Further, the Type II CSI report may be computed independently from any Type II CSI report that is carried on PUCCH formats 1, 3, or 4.

[0046] Different from the PDSCH transmission which may be relied on the CSI report, currently the downlink control channel, especially PDCCH, is transmitted by the network device using transparent precoding or beamforming for the terminal device. Robustness for PDCCH is provided via different aggregation levels (link adaptation). For example, a terminal device in the cell center may be transmitted with a low number of aggregation levels while a terminal device in cell edge may be transmitted with high number of aggregation levels. The downlink control channel reception performance is of importance since the downlink control channel is used to schedule downlink and uplink data transmissions, to trigger aperiodic CSI-RS and SRS transmissions, to provide uplink power control commands, to just name few. It may be desired to further improve downlink control channel demodulation performance and reception performance.

[0047] According to example embodiments of the present disclosure, it is proposed a solution to enable a CSI report-based PDCCH transmission scheme, to improve downlink control channel demodulation and reception performance, a scheme for CSI reporting-based downlink control channel transmission is provided. In the example embodiments of the present disclosure, channel state information associated with a downlink control channel is determined based at least in part on measurement information about a CSI-RS from a network device. A CSI report at least comprising the CSI associated with the downlink control channel is transmitted to the network device. In some example embodiments, the downlink control channel may include a physical downlink control channel (PDCCH).

[0048] With the received CSI associated with the downlink control channel, the network device determines a transmission scheme for a transmission of the downlink control channel to the terminal device based on the received channel state information. As the transmission of the downlink control channel transmission is performed on the basis of the channel state information reported by the terminal device, a more appropriate transmission scheme (e.g., precoding information for the downlink control information) may be selected so that the terminal device may be able to successfully decode and demodulate the downlink control channel.

[0049] FIG. 2 illustrates a signaling flow 200 for CSI report in accordance with some example embodiments of the present disclosure. For discussion purpose, the signaling flow200 is described with reference to FIG. 2. As illustrated, the signaling flow 200 involves the terminal device 110 and the network device 120 in FIG. 1.

[0050] At the terminal side, the terminal device 110 determines (225) CSI associated with a downlink control channel based at least in part on measurement information about a CSI- RS received from the network device 120.

[0051] The CSI may be determined to evaluate the channel status between the network device 120 and the terminal device 110. To perform the evaluation, the network device 120 may transmit (215) a reference signal (referred to as CSI-RS) to the terminal device 110. The terminal device 110 may measure (220) the CSI-RS from the network 120, to obtain the measurement information for determining the CSI.

[0052] In example embodiments of the present disclosure, the terminal device 110 may determine CSI for a downlink control channel. The downlink control channel may be configured for carrying information related to downlink control. An example of the downlink control channel may include PDCCH. In some example embodiments, the terminal device 110 may also determine CSI associated with a downlink data channel based on the measurement information of the CSI-RS received from the network device 120. In some example embodiments, the downlink data channel may be configured for carrying downlink data for the terminal device. An example of the downlink data channel may include a PDSCH. The CSI to be reported for the PDSCH may be the same or similar to those as discussed above.

[0053] The terminal device 110 transmits (230) to the network device 120, the CSI report. The CSI report at least comprises the CSI associated with the downlink control channel. The network device 120 receives (235) the CSI report from the terminal device 110. The transmission of the CSI report may be in any suitable uplink channel. In some examples, the CSI report may be transmitted within a physical uplink shared channel (PUSCH), e.g., using PUSCH resources.

[0054] In some example embodiments, in addition to the CSI associated with the downlink control channel (e.g., PDCCH), a CSI report may further include CSI associated with the downlink data channel (e.g., PDSCH). In an example, the CSI report may include separate parts of CSI associated with the downlink control channel and CSI associated with the downlink data channel. The CSI report may include a first part containing CSI associated with a downlink data channel and a second part containing the CSI associated with the downlink control channel. That is, the CSI report may include PDSCH specific CSI and PDCCH specific CSI. In another example, the terminal device 110 may indicate in the CSI report that one or more components of the CSI associated with the downlink data channelmay also be applied to the downlink control channel.

[0055] In some example embodiments, the CSI report specific to the downlink control channel may be defined to include the CSI associated with the downlink control channel. That is, the terminal device 110 may transmit a CSI report to include the CSI associated with the downlink control channel, and another CSI report to include the CSI associated with the downlink data channel.

[0056] In the signaling flow 200, the network device 120 may transmit (205) to the terminal device 110, a CSI configuration for a downlink control channel. The terminal device 110 may receive (210) from the network device 120, the CSI configuration for the downlink control channel. Through the CSI configuration, the terminal device 110 may determine that it is configured to report CSI for the downlink control channel. Otherwise, it may still report CSI for the downlink data channel only.

[0057] In some example embodiments, the CSI configuration for the downlink control channel may comprise configuration information related to precoding of the downlink control channel. In such a case, The CSI associated with the downlink control channel may be determined further based on the received CSI configuration. In some example embodiments, the terminal device 110 may provide a separate CSI report based on the CSI configuration for the downlink control channel which indicates that a CSI report specific to the downlink control channel is to be reported. In some examples, the CSI configuration may indicate the specific channel state information to be reported for the downlink control channel.

[0058] In some example embodiments, the configuration information related to precoding of the downlink control channel may indicate whether wideband precoding information is to be reported for the downlink control channel, e.g., whether wideband or sub-band precoder or PMI is to be reported for the downlink control channel. In some example embodiments, the wideband precoding information may include a wideband precoder or wideband PMI. If the wideband precoding information is configured to be reported for the downlink control channel, the terminal device 110 may calculate a single precoder or PMI for the entire resources of a control resource set (CORESET) used for transmission of the downlink control channel. The single precoder or PMI may be reported in the CSI associated with the downlink control channel.

[0059] In some example embodiments, the configuration information related to precoding of the downlink control channel may indicate whether sub-band precoding information is to be reported for the downlink control channel. In some example embodiments, the sub-band precoding information may include a sub-band based precoder or a sub-band based PMI. Ifthe sub-band precoding information is to be reported for the downlink control channel, the terminal device 110 may divide the CORESET for the downlink control channel into subbands according to a sub-band size configured for the CORESET and estimate a precoder or PMI per sub-band. The precoder or PMI per sub-ban may be reported in the CSI associated with the downlink control channel.

[0060] In some example embodiments, the terminal device 110 may provide CSI information in the CSI report targeted to the downlink control channel transmission that indicates precoding preference for the downlink control channel transmission from the point of view of the terminal device 110. The CSI associated with the downlink control channel may indicate such precoding preference for the downlink control channel.

[0061] The CSI associated with the downlink control channel may comprise precoding information for the downlink control channel. In some example embodiments, the precoding information may include an indicator of a first layer of PMI, and / or a layer index of the PMI, and / or a rank 1 PMI index.

[0062] In some example embodiments, the CSI associated with the downlink control channel may indicate whether the precoding vector of a first layer of the PMI associated with a downlink data channel is also applied (or preferred) for the downlink control channel, and / or whether a rank 1 PMI index associated with a downlink data channel is also applied (or preferred) for the downlink control channel.

[0063] The terminal device 110 may determine the precoding information associated with a downlink data channel (e.g., the PDSCH) based on the measurement information. The terminal device 110 may further estimate whether the precoding information for the downlink data channel is also preferred for the downlink control channel. In some examples, the terminal device 110 may determine whether the precoding vector of the first layer of the PMI associated with the downlink data channel (based on the assumption that first layer is the strongest layer)) is also preferred for the precoding of the downlink control channel, or whether some other rank 1 PMI would be preferred for the precoding of the downlink control channel.

[0064] If the terminal device 110 determines that the precoding information for the downlink data channel is applied for the downlink control channel, the terminal device 110 determines the CSI associated with the downlink control channel to include an indication that the precoding information for the downlink data channel is applied for the downlink control channel. The CSI associated with the downlink control channel may indicate whether a layer index of a PMI associated with a downlink data channel is applied for the control channel precoding. For example the CSI report may include the precoding information, e.g.,the PMI determined for the downlink data channel. The terminal device 110 may further include in the CSI report an indication to indicate that a precoder vector of a first layer of the PMI is applied for the downlink control channel.

[0065] In some cases, if the terminal device 110 determines that the precoding information for the downlink data channel is not applied for the downlink control channel, for example, the precoder vector of a first layer of the PMI is applied for the downlink control channel, the terminal device 110 may prepare the CSI report to include information about a rank 1 PMI index for the downlink control channel. The CSI associated with the downlink control channel may include information about a rank 1 PMI index for the downlink control channel. In this case, the terminal device 110 may indicate the corresponding rank 1 PMI index corresponding to the certain precoding vector. Here the PMI index may refer to Type I CSI codebook in case Type II codebook is used for PDSCH PMI calculation.

[0066] In some example embodiments, the CSI report may comprise at least one of the following: the PMI, the RI, the CQI, CSI feedback associated with a Type I or Type II CSI codebook associated with the data control channel. In some example embodiments, the CSI report may further include the CSI associated with the downlink control channel.

[0067] In some example embodiments, the CSI associated with the downlink control channel may be indicated in such a manner depending on the type of the CSI report (e.g., Type I or Type II). In some examples, for Type I CSI feedback, CSI Part 1 may contain RI (if reported), CRI (if reported), CQI for the first codeword, and CSI Part 2 may contain PMI, and a layer index of the PMI or rank 1 PMI index when RI <=4. The layer index of the PMI or rank 1 PMI index when RI <=4 may be associated with the downlink control channel.

[0068] In some examples, for Type II CSI feedback, CSI Part 1 may have a fixed payload size and contain RI, CQI, and an indication of the number of non-zero wideband amplitude coefficients per layer for the Type II CSI. The fields of CSI Part 1 may be separately encoded. CSI Part 2 may contain the PMI of the Type II CSI, and a layer index of the PMI or rank 1 PMI index. The layer index of the PMI or rank 1 PMI index may be associated with the downlink control channel.

[0069] In some example embodiments, the CSI report may include an additional field to carry the CSI associated with the downlink control channel, among the fields for the CSI associated with the downlink data channel. The field for the CSI associated with the downlink control channel may include one value to indicate that the precoding vector of the first layer of the indicated PMI is preferred for the precoding of the downlink control channel (e.g., for PDCCH precoding), and one or more other values to indicate that certain rank 1 PMI would be preferred for the precoding of the downlink control channel.

[0070] In some example embodiments, the CSI report may include a first additional field to include one value to indicate that the precoding vector of the first layer of the indicated PMI is preferred for the precoding of the downlink control channel (e.g., for PDCCH precoding), and one or more other values to indicate that certain rank 1 PMI would be preferred for the precoding of the downlink control channel. The CSI report may include a second additional field to indicate other channel state information associated with the downlink control channel.

[0071] In some example embodiments, in addition to the precoding information or as an alternative, CSI associated with the downlink control channel may alternatively or additionally include a channel quality value or a channel quality indicator (CQI) defined for the transmission of the downlink control channel , e.g., for the PDCCH transmission. The second field in the CSI report may indicate the determined channel quality value or CQI.

[0072] In some example embodiments, the channel quality value or CQI may be defined based on the aggregation levels applicable to the transmission of the downlink control channel. For example, a channel quality value of “00” may indicate Aggregation level 1 for the transmission of the downlink control channel; a channel quality value of “01” may indicate Aggregation level 2 for the transmission of the downlink control channe2; a channel quality value of “10” may indicate Aggregation level 4 for the transmission of the downlink control channel; and a channel quality value of “11” may indicate Aggregation level 8 for the transmission of the downlink control channel. Aggregation level 1 and Aggregation level 2 may be selected by a terminal device in or near to a cell center, and Aggregation level 4 and Aggregation level 8 may be selected by a terminal device at or near to a cell edge.

[0073] In some example embodiments, for the separate CSI reporting for the downlink control channel and the downlink data channel (either in the same CSI report or in different CSI report), the CSI associated with a downlink control channel may be defined as CSI Part 3. The CSI associated with a downlink data channel may be defined as CSI Part 1 and CSI Part 2.

[0074] For example, there may be different options for how to map CSI Part 1, Part 2 and Part 3 within an uplink transmission (e.g., a PUSCH transmission) using PUSCH resources in time domain. There may be various options for the transmission of CSI Part 1, Part 2 and Part 3 in time domain.

[0075] In some example embodiments, CSI Part 3 may be transmitted first in time, then CSI Part 1 and Part 2 may be transmitted last in time. In some example embodiments, CSI Part 1 may be transmitted first in time, then CSI Part 3 and Part 2 may be transmitted last in time. In some example embodiments, CSI Part 1 may be transmitted first in time, then CSIPart 2 and Part 3 may be transmitted last in time.

[0076] With the CSI report received from the terminal device, the network device 120 determines (240) a transmission scheme for a transmission of the downlink control channel to the terminal device (110) based on the CSI associated with the downlink control channel. In some example embodiments, the network device 120 may determine a precoder for precoding of the downlink control channel based on the CSI associated with the downlink control channel (e.g., the precoding information of the downlink control channel). The network device 120 may perform the precoding of the transmission of the downlink control channel based on the determined precoder, and transmit the downlink control channel to the terminal device 110. It should be noted that the network device 120 may or may not select the same precoder as indicated by the terminal device 110. The selection of the precoder depends on the implementations of the network device.

[0077] In some example embodiments, the network device 120 may also receive CSI associated with the downlink data channel (e.g., the PDSCH) in the same CSI report or in a separate CSI report. Similarly, the network device 120 may determine a precoder for precoding of the downlink data channel based on the CSI associated with the downlink data channel, and preform the transmission of the downlink data channel to the terminal device 110 based on the determined precoder.

[0078] FIG. 3 illustrates a specific signaling flow 300 for CSI reporting in accordance with some example embodiments of the present disclosure. The signaling flow 300 may be considered as an example of the signaling flow 200.

[0079] In the signaling flow 300, the network device 120 may transmit (305) a CSI configuration to the terminal device 110. The CSI configuration may indicate CSI measurement and reporting. The terminal device 110 may receive (310) the CSI configuration and perform the CSI measurement and reporting accordingly.

[0080] The network device 120 may perform (315) a CSI-RS transmission to the terminal device 110, and the terminal device 110 may measure (320) the CSI-RS received from the network device 120.

[0081] The terminal device 110 may estimate (325) CSI for PDSCH transmission, which may include PMI, RI, and CQI information. The terminal device 110 may determine (330) CSI for PDCCH transmission. In some example embodiments, the terminal device 110 may estimate whether the precoder vector of the first layer of PMI for PDSCH is also applied or preferred for PDCCH. If the precoder vector of the first layer is also applied for PDCCH, the terminal device 110 may prepare a CSI report to include an indication that the precoder vector of the first layer of PDSCH is also preferred for PDCCH precoding. If the precodervector of the first layer of PMI for PDSCH is also applied or preferred for PDCCH, the terminal device 110 may prepare the CSI report to include information about certain rank 1 PMI for PDCCH. The prepared CSI report may also include the PMI, RI, and CQI information estimated for PDSCH transmission.

[0082] The terminal device 110 transmits (332) the prepared CSI report to the network device 120. The network device 120 receives (335) the CSI report and may determine (340) a precoder for the PDCCH and a precoder for the PDSCH based on the channel state information included in the CSI report. Then the network device 120 may perform (345) the PDSCH transmission and the PDCCH transmission to the terminal device 110 using the respective precoders. The terminal device 110 may receive (350) the PDSCH transmission and the PDCCH transmission, and attempt to decode information from the PDSCH and PDCCH.

[0083] According to the example embodiments of the present disclosure, the downlink control channel transmission and reception performance may be improved as the transmission at the network side is performed according to the channel state information reported from the terminal device for the downlink control channel.

[0084] FIG. 4 shows a flowchart of an example method 400 implemented at a terminal device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 400 will be described from the perspective of the terminal device 110 in FIG. 1.

[0085] At block 410, the terminal device 110 determines channel state information associated with a downlink control channel based at least in part on measurement information about a channel state information reference signal from a network device.

[0086] At block 420, the terminal device 110 transmits, to the network device, a channel state information report at least comprising the channel state information associated with the downlink control channel.

[0087] In some example embodiments, the method 400 further comprises: receiving, from the network device, a channel state information configuration for the downlink control channel; and wherein the channel state information associated with the downlink control channel is determined further based on the channel state information configuration.

[0088] In some example embodiments, the channel state information configuration for the downlink control channel comprises configuration information related to precoding of the downlink control channel.

[0089] In some example embodiments, the configuration information related to precoding of the downlink control channel indicates at least one of the following: whether widebandprecoding information is to be reported for the downlink control channel, or whether subband precoding information is to be reported for the downlink control channel.

[0090] In some example embodiments, the channel state information associated with the downlink control channel comprises: an indicator of a first layer of a precoding matrix indicator, PMI, a layer index of the PMI, a rank 1 PMI index, or a channel quality value.

[0091] In some example embodiments, the channel state information associated with the downlink control channel indicates whether a precoding vector of a first layer of a precoding matrix indicator, PMI associated with a downlink data channel is applied for the downlink control channel.

[0092] In some example embodiments, the channel state information associated with the downlink control channel indicates whether a layer index of a PMI or a rank 1 PMI index associated with a downlink data channel is applied for the control channel precoding.

[0093] In some example embodiments, determining the channel state information associated with the downlink control channel comprises: determining precoding information associated with a downlink data channel based on the measurement information; and in accordance with a determination that the precoding information for the downlink data channel is applied for the downlink control channel, determining the channel state information associated with the downlink control channel to comprise an indication that the precoding information for the downlink data channel is applied for the downlink control channel; and wherein the channel state information report further comprises the precoding information associated with the downlink data channel.

[0094] In some example embodiments, the precoding information associated with the downlink data channel comprises a precoding matrix indicator, PMI; and wherein the indication indicates that a precoder vector of a first layer of the PMI is applied for the downlink control channel.

[0095] In some example embodiments, determining the channel state information associated with the downlink control channel comprises: in accordance with a determination that the precoding information for the downlink data channel is not applied for the downlink control channel, determining the channel state information associated with the downlink control channel to comprise information about a rank 1 PMI index for the downlink control channel.

[0096] In some example embodiments, the channel state information report comprises at least one of the following: a PMI, a rank indication, a channel quality indicator, channel state information feedback associated with a Type I or Type II channel state information codebook, or the channel state information associated with the downlink control channel.

[0097] In some example embodiments, the channel state information report comprises a first part containing channel state information associated with a downlink data channel and a second part containing the channel state information associated with the downlink control channel.

[0098] In some example embodiments, the channel state information report is specific to the downlink control channel.

[0099] FIG. 5 shows a flowchart of an example method 500 implemented at a network device in accordance with some example embodiments of the present disclosure. For the purpose of discussion, the method 500 will be described from the perspective of the network device 120 in FIG. 1.

[0100] At block 510, the network device 120 receives, from a terminal device, a channel state information report at least comprising channel state information associated with a downlink control channel.

[0101] At block 520, the network device 120 determines a transmission scheme for a transmission of the downlink control channel to the terminal device based on the channel state information associated with the downlink control channel.

[0102] In some example embodiments, the method 500 further comprises: transmitting, to the terminal device, a channel state information configuration for the downlink control channel, wherein the channel state information configuration for the downlink control channel comprises configuration information related to precoding of the downlink control channel.

[0103] In some example embodiments, the configuration information related to precoding of the downlink control channel indicates at least one of the following: whether wideband precoding information is to be reported for the downlink control channel, or whether subband precoding information is to be reported for the downlink control channel.

[0104] In some example embodiments, the channel state information associated with the downlink control channel comprises: an indicator of a first layer of a precoding matrix indicator, PMI, a layer index of the PMI, a rank 1 PMI index, or a channel quality value, and wherein the second apparatus is caused to determine the transmission scheme by: determining a precoder for precoding of the downlink control channel based on the channel state information associated with the downlink control channel.

[0105] In some example embodiments, the channel state information associated with the downlink control channel indicates whether a precoding vector of a first layer of a precoding matrix indicator, PMI associated with a downlink data channel is applied for the downlink control channel.

[0106] In some example embodiments, the channel state information associated with the downlink control channel indicates whether a layer index of a PMI or a rank 1 PMI index associated with a downlink data channel is applied for the control channel precoding.

[0107] In some example embodiments, the channel state information report further comprises a precoding matrix indicator, PMI, associated with a downlink data channel; and wherein the channel state information associated with the downlink control channel comprises an indication indicates that a precoder vector of a first layer of the PMI is applied for the downlink control channel.

[0108] In some example embodiments, the channel state information associated with the downlink control channel comprises information about a rank 1 PMI index for the downlink control channel.

[0109] In some example embodiments, the channel state information report comprises at least one of the following: a PMI, a rank indication, a channel quality indicator, channel state information feedback associated with a Type I or Type II channel state information codebook, or the channel state information associated with the downlink control channel.

[0110] In some example embodiments, the channel state information report comprises at least one first part containing channel state information associated with a downlink data channel and a second part containing the channel state information associated with the downlink control channel.[OHl] In some example embodiments, determining a transmission scheme comprises: determining, based on the first part, a transmission scheme for a transmission of the downlink data channel to the terminal device; and determining, based on the second part, a transmission scheme for a transmission of the downlink control channel to the terminal device.

[0112] In some example embodiments, the channel state information report is specific to the downlink control channel.

[0113] In some example embodiments, a first apparatus capable of performing any of the method 400 (for example, the terminal device 110 in FIG. 1) may comprise means for performing the respective operations of the method 400. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The first apparatus may be implemented as or included in the terminal device 110 in FIG. 1.

[0114] In some example embodiments, the first apparatus comprises means for determining channel state information associated with a downlink control channel based at least in part on measurement information about a channel state information reference signal from anetwork device; and means for transmitting, to the network device, a channel state information report at least comprising the channel state information associated with the downlink control channel.

[0115] In some example embodiments, the first apparatus further comprises: means for receiving, from the network device, a channel state information configuration for the downlink control channel; and wherein the channel state information associated with the downlink control channel is determined further based on the channel state information configuration.

[0116] In some example embodiments, the channel state information configuration for the downlink control channel comprises configuration information related to precoding of the downlink control channel.

[0117] In some example embodiments, the configuration information related to precoding of the downlink control channel indicates at least one of the following: whether wideband precoding information is to be reported for the downlink control channel, or whether subband precoding information is to be reported for the downlink control channel.

[0118] In some example embodiments, the channel state information associated with the downlink control channel comprises: an indicator of a first layer of a precoding matrix indicator, PMI, a layer index of the PMI, a rank 1 PMI index, or a channel quality value.

[0119] In some example embodiments, the channel state information associated with the downlink control channel indicates whether a precoding vector of a first layer of a precoding matrix indicator, PMI associated with a downlink data channel is applied for the downlink control channel.

[0120] In some example embodiments, the channel state information associated with the downlink control channel indicates whether a layer index of a PMI or a rank 1 PMI index associated with a downlink data channel is applied for the control channel precoding.

[0121] In some example embodiments, the means for means for determining precoding information associated with a downlink data channel comprises: means for determining precoding information associated with a downlink data channel based on the measurement information; and means for in accordance with a determination that the precoding information for the downlink data channel is applied for the downlink control channel, determining the channel state information associated with the downlink control channel to comprise an indication that the precoding information for the downlink data channel is applied for the downlink control channel; and wherein the channel state information report further comprises the precoding information associated with the downlink data channel.

[0122] In some example embodiments, the precoding information associated with thedownlink data channel comprises a precoding matrix indicator, PMI; and wherein the indication indicates that a precoder vector of a first layer of the PMI is applied for the downlink control channel.

[0123] In some example embodiments, the means for means for determining precoding information associated with a downlink data channel comprises: means for in accordance with a determination that the precoding information for the downlink data channel is not applied for the downlink control channel, determining the channel state information associated with the downlink control channel to comprise information about a rank 1 PMI index for the downlink control channel.

[0124] In some example embodiments, the channel state information report comprises at least one of the following: a PMI, a rank indication, a channel quality indicator, channel state information feedback associated with a Type I or Type II channel state information codebook, or the channel state information associated with the downlink control channel.

[0125] In some example embodiments, the channel state information report comprises a first part containing channel state information associated with a downlink data channel and a second part containing the channel state information associated with the downlink control channel.

[0126] In some example embodiments, the channel state information report is specific to the downlink control channel.

[0127] In some example embodiments, a second apparatus capable of performing any of the method 500 (for example, the network device 120 in FIG. 1) may comprise means for performing the respective operations of the method 500. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The second apparatus may be implemented as or included in the network device 120 in FIG. 1.

[0128] In some example embodiments, the second apparatus comprises means for receiving, from a terminal device, a channel state information report at least comprising channel state information associated with a downlink control channel; and means for determining a transmission scheme for a transmission of the downlink control channel to the terminal device based on the channel state information associated with the downlink control channel.

[0129] In some example embodiments, the second apparatus further comprises: means for transmitting, to the terminal device, a channel state information configuration for the downlink control channel, wherein the channel state information configuration for the downlink control channel comprises configuration information related to precoding of the downlink control channel.

[0130] In some example embodiments, the configuration information related to precoding of the downlink control channel indicates at least one of the following: whether wideband precoding information is to be reported for the downlink control channel, or whether subband precoding information is to be reported for the downlink control channel.

[0131] In some example embodiments, the channel state information associated with the downlink control channel comprises: an indicator of a first layer of a precoding matrix indicator, PMI, a layer index of the PMI, a rank 1 PMI index, or a channel quality value, and wherein the second apparatus is caused to determine the transmission scheme by: determining a precoder for precoding of the downlink control channel based on the channel state information associated with the downlink control channel.

[0132] In some example embodiments, the channel state information associated with the downlink control channel indicates whether a precoding vector of a first layer of a precoding matrix indicator, PMI associated with a downlink data channel is applied for the downlink control channel.

[0133] In some example embodiments, the channel state information associated with the downlink control channel indicates whether a layer index of a PMI or a rank 1 PMI index associated with a downlink data channel is applied for the control channel precoding.

[0134] In some example embodiments, the channel state information report further comprises a precoding matrix indicator, PMI, associated with a downlink data channel; and wherein the channel state information associated with the downlink control channel comprises an indication indicates that a precoder vector of a first layer of the PMI is applied for the downlink control channel.

[0135] In some example embodiments, the channel state information associated with the downlink control channel comprises information about a rank 1 PMI index for the downlink control channel.

[0136] In some example embodiments, the channel state information report comprises at least one of the following: a PMI, a rank indication, a channel quality indicator, channel state information feedback associated with a Type I or Type II channel state information codebook, or the channel state information associated with the downlink control channel.

[0137] In some example embodiments, the channel state information report comprises at least one first part containing channel state information associated with a downlink data channel and a second part containing the channel state information associated with the downlink control channel.

[0138] In some example embodiments, the means for determining a transmission scheme comprises: means for determining, based on the first part, a transmission scheme for atransmission of the downlink data channel to the terminal device; and means for determining, based on the second part, a transmission scheme for a transmission of the downlink control channel to the terminal device.

[0139] In some example embodiments, the channel state information report is specific to the downlink control channel.

[0140] FIG. 6 is a simplified block diagram of a device 600 that is suitable for implementing example embodiments of the present disclosure. The device 600 may be provided to implement a communication device, for example, the terminal device 16 or the network device 120 as shown in FIG. 1. As shown, the device 600 includes one or more processors 66, one or more memories 620 coupled to the processor 66, and one or more communication modules 640 coupled to the processor 66.

[0141] The communication module 640 is for bidirectional communications. The communication module 640 has one or more communication interfaces to facilitate communication with one or more other modules or devices. The communication interfaces may represent any interface that is necessary for communication with other network elements. In some example embodiments, the communication module 640 may include at least one antenna.

[0142] The processor 66 may be of any type suitable to the local technical network and may include one or more of the following: general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 600 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

[0143] The memory 620 may include one or more non-volatile memories and one or more volatile memories. Examples of the non-volatile memories include, but are not limited to, a Read Only Memory (ROM) 624, an electrically programmable read only memory (EPROM), a flash memory, a hard disk, a compact disc (CD), a digital video disk (DVD), an optical disk, a laser disk, and other magnetic storage and / or optical storage. Examples of the volatile memories include, but are not limited to, a random-access memory (RAM) 622 and other volatile memories that will not last in the power-down duration.

[0144] A computer program 630 includes computer executable instructions that are executed by the associated processor 66. The instructions of the program 630 may include instructions for performing operations / acts of some example embodiments of the present disclosure. The program 630 may be stored in the memory, e.g., the ROM 624. The processor 66 may perform any suitable actions and processing by loading the program 630 into theRAM 622.

[0145] The example embodiments of the present disclosure may be implemented by means of the program 630 so that the device 600 may perform any process of the disclosure as discussed with reference to FIG. 3A to FIG. 9. The example embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

[0146] In some example embodiments, the program 630 may be tangibly contained in a computer readable medium which may be included in the device 600 (such as in the memory 620) or other storage devices that are accessible by the device 600. The device 600 may load the program 630 from the computer readable medium to the RAM 622 for execution. In some example embodiments, the computer readable medium may include any types of non- transitory storage medium, such as ROM, EPROM, a flash memory, a hard disk, CD, DVD, and the like. The term “non-transitory,” as used herein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM).

[0147] FIG. 7 shows an example of the computer readable medium 160 which may be in form of CD, DVD or other optical storage disk. The computer readable medium 160 has the program 630 stored thereon.

[0148] Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, and other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. Although various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

[0149] Some example embodiments of the present disclosure also provide at least one computer program product tangibly stored on a computer readable medium, such as a non- transitory computer readable medium. The computer program product includes computerexecutable instructions, such as those included in program modules, being executed in a device on a target physical or virtual processor, to carry out any of the methods as described above. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particularabstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

[0150] Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. The 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 the program code, when executed by the processor or controller, cause the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

[0151] In the context of the present disclosure, the computer program code or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable medium, and the like.

[0152] The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include an electrical connection having 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 disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0153] Further, although operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, although several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Unless explicitly stated, certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment.Conversely, unless explicitly stated, various features that are described in the context of a single embodiment may also be implemented in a plurality of embodiments separately or in any suitable sub-combination.

[0154] Although the present disclosure has been described in languages specific to structural features and / or methodological acts, it is to be understood that the present disclosure 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

WHAT IS CLAIMED IS:

1. A first apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus at least to: determine channel state information associated with a downlink control channel based at least in part on measurement information about a channel state information reference signal from a network device; and transmit, to the network device, a channel state information report at least comprising the channel state information associated with the downlink control channel; wherein the channel state information associated with the downlink control channel indicates one of: whether a precoding vector of a first layer of a precoding matrix indicator, PMI associated with a downlink data channel is applied for the downlink control channel; or whether a layer index of a PMI or a rank 1 PMI index associated with a downlink data channel is applied for the downlink control channel precoding.

2. The first apparatus of claim 1, wherein the first apparatus is further caused to: receive, from the network device, a channel state information configuration for the downlink control channel; and wherein the channel state information associated with the downlink control channel is determined further based on the channel state information configuration.

3. The first apparatus of claim 2, wherein the channel state information configuration for the downlink control channel comprises configuration information related to precoding of the downlink control channel.

4. The first apparatus of claim 3, wherein the configuration information related to precoding of the downlink control channel indicates at least one of the following: whether wideband precoding information is to be reported for the downlink control channel, or whether sub-band precoding information is to be reported for the downlink control channel.

5. The first apparatus of any of claims 1 to 4, wherein the channel state information associated with the downlink control channel comprises: an indicator of a first layer of a precoding matrix indicator, PMI, a layer index of the PMI, a rank 1 PMI index, or a channel quality value.

6. The first apparatus of any of claims 1 to 7, wherein the first apparatus is caused to: determine precoding information associated with a downlink data channel based on the measurement information; and in accordance with a determination that the precoding information for the downlink data channel is applied for the downlink control channel, determine the channel state information associated with the downlink control channel to comprise an indication that the precoding information for the downlink data channel is applied for the downlink control channel; and wherein the channel state information report further comprises the precoding information associated with the downlink data channel.

7. The first apparatus of claim 6, wherein the precoding information associated with the downlink data channel comprises a precoding matrix indicator, PMI; and wherein the indication indicates that a precoder vector of a first layer of the PMI is applied for the downlink control channel.

8. The first apparatus of claim 6 or 7, wherein the first apparatus is caused to: in accordance with a determination that the precoding information for the downlink data channel is not applied for the downlink control channel, determine the channel state information associated with the downlink control channel to comprise information about a rank 1 PMI index for the downlink control channel.

9. The first apparatus of any of claims 1 to 8, wherein the channel state information report comprises at least one of the following: a PMI, a rank indication, a channel quality indicator, channel state information feedback associated with a Type I or Type II channel state information codebook, orthe channel state information associated with the downlink control channel.

10. The first apparatus of any of claims 1 to 9, wherein the channel state information report comprises a first part containing channel state information associated with a downlink data channel and a second part containing the channel state information associated with the downlink control channel.

11. The first apparatus of any of claims 1 to 10, wherein the channel state information report is specific to the downlink control channel.

12. A second apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the second apparatus at least to: receive, from a terminal device, a channel state information report at least comprising channel state information associated with a downlink control channel; and determine a transmission scheme for a transmission of the downlink control channel to the terminal device based on the channel state information associated with the downlink control channel; wherein the channel state information associated with the downlink control channel indicates one of: whether a precoding vector of a first layer of a precoding matrix indicator, PMI associated with a downlink data channel is applied for the downlink control channel; or whether a layer index of a PMI or a rank 1 PMI index associated with a downlink data channel is applied for the downlink control channel precoding.

13. The second apparatus of claim 12, wherein the second apparatus is further caused to: transmit, to the terminal device, a channel state information configuration for the downlink control channel, wherein the channel state information configuration for the downlink control channel comprises configuration information related to precoding of the downlink control channel.

14. The second apparatus of claim 13, wherein the configuration information related to precoding of the downlink control channel indicates at least one of the following: whether wideband precoding information is to be reported for the downlink control channel,or whether sub-band precoding information is to be reported for the downlink control channel.

15. The second apparatus of any of claims 12 to 14, wherein the channel state information associated with the downlink control channel comprises: an indicator of a first layer of a precoding matrix indicator, PMI, a layer index of the PMI, a rank 1 PMI index, or a channel quality value, and wherein the second apparatus is caused to determine the transmission scheme by: determining a precoder for precoding of the downlink control channel based on the channel state information associated with the downlink control channel.

16. The second apparatus of any of claims 12 to 15, wherein the channel state information report further comprises a precoding matrix indicator, PMI, associated with a downlink data channel; and wherein the channel state information associated with the downlink control channel comprises an indication indicates that a precoder vector of a first layer of the PMI is applied for the downlink control channel.

17. The second apparatus of any of claims 12 to 16, wherein the channel state information associated with the downlink control channel comprises information about a rank 1 PMI index for the downlink control channel.

18. The second apparatus of any of claims 12 to 17, wherein the channel state information report comprises at least one of the following: a PMI, a rank indication, a channel quality indicator, channel state information feedback associated with a Type I or Type II channel state information codebook, or the channel state information associated with the downlink control channel.

19. The second apparatus of any of claims 12 to 18, wherein the channel state information report comprises at least one first part containing channel state information associated with adownlink data channel and a second part containing the channel state information associated with the downlink control channel.

20. The second apparatus of claim 19, wherein the second apparatus is caused to: determine, based on the first part, a transmission scheme for a transmission of the downlink data channel to the terminal device; and determine, based on the second part, a transmission scheme for a transmission of the downlink control channel to the terminal device.

21. The second apparatus of any of claims 12 to 20, wherein the channel state information report is specific to the downlink control channel.

22. A method comprising: determining channel state information associated with a downlink control channel based at least in part on measurement information about a channel state information reference signal from a network device; and transmitting, by a first apparatus and to a network device the network device, a channel state information report at least comprising the channel state information associated with the downlink control channel; wherein the channel state information associated with the downlink control channel indicates one of: whether a precoding vector of a first layer of a precoding matrix indicator, PMI associated with a downlink data channel is applied for the downlink control channel; or whether a layer index of a PMI or a rank 1 PMI index associated with a downlink data channel is applied for the downlink control channel precoding.

23. A method comprising: receiving, by a second apparatus from a terminal device, a channel state information report at least comprising channel state information associated with a downlink control channel; and determining a transmission scheme for a transmission of the downlink control channel to the terminal device based on the channel state information associated with the downlink control channel; wherein the channel state information associated with the downlink control channel indicates one of: whether a precoding vector of a first layer of a precoding matrix indicator, PMI associatedwith a downlink data channel is applied for the downlink control channel; or whether a layer index of a PMI or a rank 1 PMI index associated with a downlink data channel is applied for the downlink control channel precoding.

24. A first apparatus comprising: means for determining channel state information associated with a downlink control channel based at least in part on measurement information about a channel state information reference signal from a network device; and means for transmitting, by a first apparatus and to a network device the network device, a channel state information report at least comprising the channel state information associated with the downlink control channel; wherein the channel state information associated with the downlink control channel indicates one of: whether a precoding vector of a first layer of a precoding matrix indicator, PMI associated with a downlink data channel is applied for the downlink control channel; or whether a layer index of a PMI or a rank 1 PMI index associated with a downlink data channel is applied for the downlink control channel precoding.

25. A second apparatus comprising: means for receiving, from a terminal device, a channel state information report at least comprising channel state information associated with a downlink control channel; and means for determining a transmission scheme for a transmission of the downlink control channel to the terminal device based on the channel state information associated with the downlink control channel; wherein the channel state information associated with the downlink control channel indicates one of: whether a precoding vector of a first layer of a precoding matrix indicator, PMI associated with a downlink data channel is applied for the downlink control channel; or whether a layer index of a PMI or a rank 1 PMI index associated with a downlink data channel is applied for the downlink control channel precoding.

26. A computer readable medium comprising instructions stored thereon for causing an apparatus at least to perform the method of claim 22 or the method of claim 23.

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