Correlation-based control channel quality reporting

Abstract

A communication device (10) receives one or more wireless transmissions from a further communication device (100). The one or more wireless transmissions carry a data channel (310) and a control channel (320). Further, the communication device (10) determines correlation of quality of the data channel (310) and quality of the control channel (320). Based on the determined correlation, the communication device (10) sends a report to the further communication device (100). The report indicates whether there is a lack of correlation of quality of the control channel (320) and quality of the data channel (310).

Description

[0001] P110507W001

[0002] - 1 -

[0003] Correlation-based control channel quality reporting

[0004] Technical Field

[0005] The present invention relates to methods for communication in a wireless communication network and to corresponding devices, systems, and computer programs.

[0006] Background

[0007] In wireless communication networks, e.g., based on the 4G (4th Generation) LTE (Long Term Evolution) or 5G (5th Generation) NR technology as specified by 3GPP (3rd Generation Partnership Project), control channels may be provided for purposes of controlling the transmission of data on a data channel. For example, the LTE technology and the NR technology provide a control channel referred to as Physical Downlink Control Channel (PDCCH) and data channels referred to as PDSCH (Physical Downlink Shared Channel) and PUSCH (Physical Uplink Shared Channel). On the PDCCH, a radio access node, in the LTE technology denoted as “eNB” and in the NR technology denoted as “gNB” sends Downlink Control Information (DCI) to a User Equipment (UE). The DCI may for example include scheduling information in the form of downlink, DL, assignments and uplink, UL, grants, which informs the UE about a data transmission on one of the data channels. For example, the DCI may include a DL assignment which informs the UE about resources of an upcoming DL data transmission on the PDSCH, or the DCI may include a UL grant which informs the UE about resources to be used by the UE for a UL data transmission on the PUSCH. In each case, the DCI may indicate transmission parameters of the upcoming data transmission, such as bandwidth, time / frequency resources, and Modulation and Coding Scheme (MCS).

[0008] The size of DCI which needs to be conveyed on the PDCCH may vary, e.g., depending on the scheduling decisions made for a given time slot. Each scheduling decision requires PDCCH resources to convey the corresponding DCI. Further, the amount of required PDCCH resources depends on quality of the PDCCH. If the UE experiences good quality of the PDCCH, a smaller amount of resources may allow for transmitting the DCI than in a situation where the UE experiences poor quality of the PDCCH. This may be addressed by using PDCCH link adaptation (PDCCH LA). By PDCCH LA, the number of resources assigned to the PDCCH, typically in terms of CCEs (Control Channel Elements) is adapted depending on the quality of the PDCCH, with the aim of achieving a certain block error rate (BLER) target for the UE’s PDCCH. By increasing the amount of resources assigned to the PDCCH, robustness of DCI transmissions may be increased (so that the BLER target can be met). A further aspect P110507WQ01

[0009] - 2 - is capacity of the PDCCH: By increasing the resource region for PDCCH, it is also possible to increase the amount of DCI information that can be transmitted on the PDCCH. PDCCH LA may also balance a tradeoff between PDCCH capacity, e.g., in terms how many scheduling commands can be sent in a slot, and achievable BLER performance.

[0010] In the existing PDCCH LA mechanisms of the NR technology, there is no way for explicitly informing the gNB about quality of the PDCCH, and the gNB relies on other metrics, such as CSI (Channel State Information) or CQI (Channel Quality Indicator) reports for the PDSCH, to indirectly infer quality of the PDCCH.

[0011] Although both PDCCH and PDSCH are on the same frequency of the same direction, quality of the PDCCH and quality of the PDSCH can however deviate significantly, e.g., due to interference or different levels of resource utilization. For example, in some situations, utilization of resources of the PDCCH can be much higher than utilization of resources of the PDSCH, which may result in the quality of the PDCCH being degraded relative to the PDSCH. In other situations, utilization of resources of the PDSCH could be much higher than utilization of resources of the PDCCH, which may result in the quality of the PDSCH being degraded relative to the PDCCH. Further, in a neighbor cell there might be a UL heavy transmission activity or many UEs with very little data to send. In this case the neighbor cell PDCCH activity could create strong interference on the PDCCH of the considered cell, but not on the PDSCH of the considered cell. As result, the UE may report good quality on PDSCH to the gNB. Such report may mislead the gNB to assume also good quality on the PDCCH, which may in turn compromise the BLER performance resulting from PDCCH LA.

[0012] In some cases, usage of PDSCH CQI reports or PDSCH CSI reports as input for PDCCH LA may have the effect that PDCCH LA operates in an excessively aggressive manner. In other cases, PDCCH LA could in turn operate in an overly conservative manner. Aggressive strategies may result in bad BLER performance. Conservative strategies may in turn create capacity issues, while providing only marginal improvements in terms of BLER performance.

[0013] Accordingly, there is a need for techniques which allow for implementing link adaptation for a control channel in an efficient and accurate manner.

[0014] According to an embodiment, a method of controlling wireless communication is provided.

[0015] According to the method, a communication device receives one or more wireless P110507W001

[0016] - 3 - transmissions from a further communication device. The one or more wireless transmissions carry a data channel and a control channel. Further, the communication device determines correlation of quality of the data channel and quality of the control channel. Based on the determined correlation, the communication device sends a report to the further communication device. The report indicates whether there is a lack of correlation of quality of the control channel and quality of the data channel.

[0017] According to a further embodiment, a method of controlling wireless communication is provided. According to the method, a communication device sends one or more wireless transmissions to a further communication device. The one or more wireless transmissions carry a data channel and a control channel. Further, the communication device receives a report from the further communication device. The report indicates whether there is a lack of correlation of quality of the control channel and quality of the data channel. Based on the report, the communication device adapts transmission of the control channel.

[0018] According to a further embodiment, a communication device for operation in a wireless communication network is provided. The communication device is configured to receive one or more wireless transmissions from a further communication device. The one or more wireless transmissions carry a data channel and a control channel. Further, the communication device is configured to determine correlation of quality of the data channel and quality of the control channel. Further, the communication device is configured to, based on the determined correlation, send a report to the further communication device. The report indicates whether there is a lack of correlation of quality of the control channel and quality of the data channel.

[0019] According to a further embodiment, a communication device for operation in a wireless communication network is provided. The communication device comprises at least one processor and a memory. The memory contains instructions executable by said at least one processor, whereby the communication device is operative to receive one or more wireless transmissions from a further communication device. The one or more wireless transmissions carry a data channel and a control channel. Further, the memory contains instructions executable by said at least one processor, whereby the communication device is operative to determine correlation of quality of the data channel and quality of the control channel. Further, the memory contains instructions executable by said at least one processor, whereby the communication device is operative to, based on the determined correlation, send a report to the further communication device. The report indicates whether there is a lack of correlation of quality of the control channel and quality of the data channel. P110507W001

[0020] - 4 -

[0021] According to a further embodiment, a communication device for operation in a wireless communication network is provided. The communication device is configured to send one or more wireless transmissions to a further communication device. The one or more wireless transmissions carry a data channel and a control channel. Further, the communication device is configured to receive a report from the further communication device. The report indicates whether there is a lack of correlation of quality of the control channel and quality of the data channel. Further, the communication device is configured to, based on the report, adapt transmission of the control channel.

[0022] According to a further embodiment, a communication device for operation in a wireless communication network is provided. The communication device comprises at least one processor and a memory. The memory contains instructions executable by said at least one processor, whereby the communication device is operative to send one or more wireless transmissions to a further communication device. The one or more wireless transmissions carry a data channel and a control channel Further, the memory contains instructions executable by said at least one processor, whereby the communication device is operative to receive a report from the further communication device. The report indicates whether there is a lack of correlation of quality of the control channel and quality of the data channel. Further, the memory contains instructions executable by said at least one processor, whereby the communication device is operative to, based on the report, adapt transmission of the control channel.

[0023] According to a further embodiment of the invention, a computer program or computer program product is provided, e.g., in the form of a non-transitory storage medium, which comprises program code to be executed by at least one processor of a communication device. Execution of the program code causes the communication device to receive one or more wireless transmissions from a further communication device. The one or more wireless transmissions carry a data channel and a control channel. Further, execution of the program code causes the communication device to determine correlation of quality of the data channel and quality of the control channel. Further, execution of the program code causes the communication device to, based on the determined correlation, send a report to the further communication device. The report indicates whether there is a lack of correlation of quality of the control channel and quality of the data channel.

[0024] According to a further embodiment of the invention, a computer program or computer program product is provided, e.g., in the form of a non-transitory storage medium, which comprises program code to be executed by at least one processor of a communication device. Execution P110507W001

[0025] - 5 - of the program code causes the communication device to send one or more wireless transmissions to a further communication device. The one or more wireless transmissions carry a data channel and a control channel. Further, execution of the program code causes the communication device to receive a report from the further communication device. The report indicates whether there is a lack of correlation of quality of the control channel and quality of the data channel. Further, execution of the program code causes the communication device to, based on the report, adapt transmission of the control channel.

[0026] Details of such embodiments and further embodiments will be apparent from the following detailed description of embodiments.

[0027] Brief Description of the Drawings

[0028] Fig. 1 schematically illustrates a wireless communication network according to an embodiment.

[0029] Fig. 2 schematically illustrates an example of sample distribution of data channel quality and control channel quality.

[0030] Fig. 3 schematically illustrates an example of a link-adaptation architecture according to an embodiment.

[0031] Fig. 4 schematically illustrates an example of a link-adaptation processes according to an embodiment.

[0032] Fig. 5 schematically illustrates a further example of a link-adaptation architecture according to an embodiment.

[0033] Fig. 6 schematically illustrates a further example of a link-adaptation processes according to an embodiment.

[0034] Fig. 7 shows a flowchart for schematically illustrating a method according to an embodiment.

[0035] Fig. 8 shows a flowchart for schematically illustrating a further method according to an embodiment.

[0036] Fig. 9 schematically illustrates structures of a wireless device according to an embodiment. P110507W001

[0037] - 6 -

[0038] Fig. 10 schematically illustrates structures of a network node according to an embodiment.

[0039] Detailed Description

[0040] In the following, concepts in accordance with exemplary embodiments of the invention will be explained in more detail and with reference to the accompanying drawings. The illustrated embodiments relate to wireless communication in a wireless communication network, utilizing at least one control channel and at least one data channel. The wireless communication network may be based on the 5G NR technology. However, other technologies could be used as well, e.g., the 4G LTE technology or a future 6G (6th Generation) technology. The control channel(s) and the data channel(s) are carried by wireless transmissions between communication devices. Such communication devices may include an access node of the wireless communication network, e.g., a gNB of the NR technology, and a UE which is wirelessly connected to the access node. However, other constellations of communication devices could be considered as well, such as two UEs engaged in direct device-to-device communication, e.g., using a sidelink communication mode as for example provided in the NR technology or the LTE technology.

[0041] In the illustrated concepts, reporting of quality of a control channel is based on correlation of quality of the control channel and quality of a data channel. In this way, it for example becomes possible to base link adaptation of the control channel on reported quality of the data channel, if there is sufficient correlation of the quality of the control channel and the quality of the data channel. For this purpose, a communication device which receives one or more wireless transmissions carrying a data channel and a control channel from another communication device, may determine correlation of quality of the control channel and quality of the data channel and then send a report to the other communication device which indicates whether there is a lack of correlation of the quality of the control channel and the quality of the data channel. For this purpose, the report could for example include an explicit indicator of the lack of correlation, e.g., in the form of a binary value or a ternary value. The indicator can for example indicate whether or not quality of the data channel may be regarded as being representative of quality of the control channel. Further, such indicator could indicate that quality of the data channel is higher than quality of the control channel or that quality of the data channel may is lower than quality of the control channel. In some case, the report could also implicitly indicate whether there is a lack of correlation of the quality of the control channel and the quality of the data channel. For example, if there is a lack of correlation of the quality of the control channel and the quality of the data channel, the report could indicate the quality of the control channel. In other words, the quality of the control channel could be reported in a P110507W001

[0042] - 7 - conditional manner, if the quality of the control channel is found to lack correlation to quality of the data channel. In some cases, the report could also include a metric which represents the relation of quality of the control channel to quality of the data channel.

[0043] The communication devices could for example be a UE and an access node, e.g., a gNB, and the control channel could be a PDCCH, and the data channel could be a PDSCH. In accordance with the illustrated concepts, the UE could assess the quality of the PDSCH and the quality of the PDCCH and determine a metric that statistically or deterministically defines a relationship between the quality of the PDSCH and the quality of the PDCCH. The quantitative metric may then be processed and be used as a basis for triggering one or more configured actions, such as reporting one or more quantities to the access node. The access node may receive such report(s) and adjusts its PDCCH LA accordingly. More specifically, the UE could detect a quality mismatch between the PDCCH and the PDSCH, and provide a report to the access node to inform about the quality mismatch. The access node may use the reported information as input for adjusting the PDCCH LA strategy.

[0044] Fig. 1 illustrates exemplary structures of the wireless communication network. In particular, Fig. 1 shows UEs 10 within and in vicinity of a cell 110 which is served by an access node 100 of the wireless communication network. Here, it is noted that the wireless communication network may actually include a plurality of access nodes 100 that may serve a number of cells within the coverage area of the wireless communication network. The access node 100 may for example correspond to a radio access node of a future 6G technology, an eNB of the LTE technology, or to a gNB of the NR technology.

[0045] The access nodes 100 may be regarded as being part of an RAN of the wireless communication network. Further, Fig. 1 schematically illustrates a CN (Core Network) 210 of the wireless communication network. In Fig. 2, the CN 210 is illustrated as including a GW (gateway) 220 and one or more control node(s) 240. The GW 220 may be responsible for handling user plane data traffic of the UEs 10, e.g., by forwarding user plane data traffic from a UE 10 to a network destination or by forwarding user plane data traffic from a network source to a UE 10. Here, the network destination may correspond to another UE 10, to an internal node of the wireless communication network, or to an external node which is connected to the wireless communication network. Similarly, the network source may correspond to another UE 10, to an internal node of the wireless communication network, or to an external node which is connected to the wireless communication network. The GW 220 may for example correspond to a UPF (User Plane Function) of the 5G Core (EGC) or to an SGW (Serving Gateway) or PGW (Packet Data Gateway) of the 4G EPC (Evolved Packet Core), or to corresponding P110507W001

[0046] - 8 - nodes of a 6G ON. The control node(s) 240 may for example be used for controlling the user data traffic, e.g., by providing control data to the access node 100, the GW 220, and / or to the UE 10.

[0047] As illustrated by double-headed arrows, the access node 100 may send DL wireless transmissions to at least some of the UEs 10, and some of the UEs 10 may send UL wireless transmissions to the access node 100. Further, SL wireless transmissions could be performed directly between two or more of the UEs, e.g., for setting up a relay-based connection to the access node 100. Accordingly, the DL wireless transmissions, UL wireless transmissions, and / or SL wireless transmissions may be used on various kinds of wireless links, including wireless links between UE 10 and access node 100, direct wireless links between UEs, and relay wireless links between a remote UE 10, via a relay UE 10, and the access node 100. The DL wireless transmissions, UL wireless transmissions, and / or SL wireless transmissions may be used to provide various kinds of services to the UEs 10, e.g., a voice service, a multimedia service, or some other data service. Such services may be hosted in the CN 210, e.g., by a corresponding network node. By way of example, Fig. 1 illustrates an application service platform 250 provided in the CN 210. Further, such services may be hosted externally, e.g., by an AF (application function) connected to the CN 210. By way of example, Fig. 1 illustrates one or more application servers 300 connected to the CN 210. The application server(s) 300 could for example connect through the Internet or some other wide area communication network to the CN 210. The application service platform 250 may be based on a server or a cloud computing system and be hosted by one or more host computers. Similarly, the application server(s) 300 may be based on a server or a cloud computing system and be hosted by one or more host computers. The application server(s) 300 may include or be associated with one or more AFs that enable interaction with the CN 210 to provide one or more services to the UEs 10, corresponding to one or more applications. These services or applications may generate the user data traffic conveyed by the DL transmissions and / or the UL transmissions. Accordingly, the application server(s) 300 may include or correspond to the above-mentioned network destination and / or network source for the user data traffic. In the respective UE 10, such service may be based on an application (or shortly “app”) which is executed on the UE 10. Such application may be pre-installed or installed by the user. Such application may generate at least a part of the user plane data traffic between the UEs 10 and the access node 100.

[0048] In accordance with the illustrated concepts, the DL wireless transmissions may carry a PDCCH and a PDSCH from the access node 100 to the respective UE 10. The UL wireless transmissions may in turn carry an PUSCH and a PUCCH (Physical Uplink Control Channel) P110507W001

[0049] - 9 - from the UE 10 to the access node. Further, the SL wireless transmissions may carry a PSSCH (Physical Sidelink Shared Channel) and a PSCCH (Physical Sidelink Control Channel) between two UEs 10.

[0050] The UE 10 may monitor and estimate the quality of the PDSCH. For this purpose, the UE 10 may apply existing mechanisms as for example specified in the NR technology. The monitoring and estimation of the quality of the PDSCH may be based on a monitoring and reporting configuration provided by the access node 100, e.g., using RRC (Radio Resource Control) configuration. Further, the UE 10 may monitor and estimate the quality of PDCCH. The monitoring and estimation of the quality of the PDCCH may be based on a monitoring and reporting configuration provided by the access node 100, e.g., using RRC configuration.

[0051] The UE 10 may then correlate the quality of the PDCCH and the quality of the PDSCH, e.g., with the aim of calculating a metric that captures how closely related the quality of the PDSCH and the quality of the PDCCH are. The metric may then be stored by the UE 10. Correlation of the qualities and calculation of the metric may be based on a configuration provided by the access node 100, e.g., using RRC configuration.

[0052] Based on the calculated and stored metric, the UE 10 may then control reporting of information to the access node 100. For this purpose, the UE 10 may apply a reporting rule, which may be configured by the access node 100, e.g., using RRC configuration. If the metric satisfies one or more conditions defined by the reporting rule, the UE 10 may report the metric or some other information which is based on the metric to the access node 100. Based on the reported information, the access node 100 may then perform one or more follow up actions, such as adjusting its PDCCH LA strategy.

[0053] In a similar manner, a UE 10 engaged in SL communication with another UE 10 may monitor and estimate the quality of the PSSCH. For this purpose, the UE 10 may apply existing mechanisms as for example specified in the NR technology. The monitoring and estimation of the quality of the PSSCH may be based on a monitoring and reporting configuration provided by the access node 100 or the other UE 10, e.g., using RRC configuration. Further, the UE 10 may monitor and estimate the quality of PSCCH. The monitoring and estimation of the quality of the PSCCH may be based on a monitoring and reporting configuration provided by the access node 100 or the other UE 10, e.g., using RRC configuration.

[0054] The UE 10 may then correlate the quality of the PSCCH and the quality of the PSSCH, e.g., with the aim of calculating a metric that captures how closely related the quality of the PSSCH P110507WQ01

[0055] - 10 - and the quality of the PSCCH are. The metric may then be stored by the UE 10. Correlation of the qualities and calculation of the metric may be based on a configuration provided by the access node 100 or the other UE 10, e.g., using RRC configuration.

[0056] Based on the calculated and stored metric, the UE 10 may then control reporting of information to the other UE 10. For this purpose, the UE 10 may apply a reporting rule, which may be configured by the access node 100 or the other UE 10, e.g., using RRC configuration. If the metric satisfies one or more conditions defined by the reporting rule, the UE 10 may report the metric or some other information which is based on the metric to the other UE 10. Based on the reported information, the other UE 10 may then perform one or more follow up actions, such as adjusting its PSCCH LA strategy.

[0057] Estimation of quality of the PDSCH may be performed on measurements on CSI-RS (Channel State Information Reference Signal) resources and / or on CSI-IM (Channel State Information Interference Measurement) resources. The CSI-RS resources and / or CSI-IM resources may be configured by the access node 100, e.g., using RRC configuration. In a given measurement slot, the UE 10 may perform measurements on the configured resources and derive a quality metric, such as a CQI (Channel Quality Indicator) or a SINR (Signal-to-lnterference-and Noise Ratio), for the PDSCH.

[0058] For estimating the quality of the PDCCH, the UE 10 can perform measurements on DMRS (Demodulation Reference Signals) within DCI to capture. Based on the measurements, the UE 10 can derive a quality metric, such as a CQI or a SINR, for the PDCCH. In addition or as an alternative, would also be possible to base the estimation of the quality of the PDCCH on reference signals which are dedicated for the purpose of the PDCCH quality estimation. According to an example, the UE 10 may be configured with a CSI-IM resource in the timefrequency region for PDCCH reception, and quality of the PDCCH may be estimated from measurements on this CSI-IM resource. In some such examples, the UE 10 may be configured with a CSI-RS resource to be used for estimating the quality of both PDSCH and PDCCH. In addition or as an alternative, the UE 10 may be configured with two CSI-IM resources, one being located in the time-frequency region for PDSCH reception and used for PDSCH interference estimation of the PDSCH and the other being located in the time-frequency region for PDCCH reception and used for interference estimation of the PDCCH. In such scenarios, the CSI-IM for PDCCH quality estimation may configured to overlap one or more CCEs and the search space may be designed to never include these CCEs in the search space set. In another example, the CSI-IM for PDCCH quality estimation may use resource elements from P110507WQ01

[0059] - 11 - multiple CCEs and both the access node 100 and the UE 10 may exclude these resource elements the rate matching of the PDCCH.

[0060] In any of the examples illustrated herein, the quality of the PDCCH and / or of the PDSCH may be represented as SINR or as mutual / symbol information indicating useful information bits per symbol. Since the beamforming on PDCCH and PDSCH can be different, the quality of the PDSCH can be rank adjusted. For example, if the PDCCH is rank limited to 1 and PDSCH has rank r and the quality metric is SINR in dB domain, the quality of the PDSCH, denoted as PDSCH_quality, can be rank-adjusted to PDSCH_quality + 10*logio(r). In another example, the quality of the PDSCH may be rank adjusted to PDSCH_quality + 10*logio(r) + offset, where offset could be a configuration parameter with purpose to compensate for inter-layer interference. In some examples, offset is a parameter depending on the rank r. In further examples, where the quality metric is represented in terms of useful information bits per symbol, the adjustment may be based on rank and modulation. For example, the PDCCH could be limited to rank 1 and QPSK (Quadrature Phase Shift Keying) modulation while the PDSCH may have a higher rank and higher order modulation. In such cases, adjustment can be done in various ways. For example, the value of useful information bits per symbol for the PDSCH could first be converted to a rank-specific SINR measure using modulation-specific SINR-to- symbol information relations, and then the rank-specific SINR could be adjusted as in the previous examples. Then, the adjusted SINR could be converted to a value of useful information bits per symbol using a SINR-to-symbol information relation for QPSK.

[0061] For correlating the quality of the PDCCH and the quality of the PDSCH, the UE 10 may compare the quality of PDCCH and the quality of the PDSCH and calculates a correlation metric corresponding to a quantitative measure that represents a relation between quality of the PDCCH and quality of the PDSCH. As mentioned above, the qualities could be represented in terms of SINRs or values of useful information bits per symbol.

[0062] In some scenarios, the correlation metric can be calculated based on statistical or deterministic approaches. For example, when denoting and Ynthe measured quality of the PDCCH at sample n by Xn, and denoting the measured quality of the PDSCH at sample n by Yn, the UE 10 could calculate the difference between quality of the PDCCH and quality of the PDSCH in terms of Xn- Yn. In another option, the UE 10 could calculate the difference between a mean value of the quality of the PDCCH, given by ji^ = £n=1Xn,and amean value of the quality The correlation metric could in this case be calculated P110507W001

[0063] - 12 -

[0064] In a further option, the UE 10 may calculate the difference between a sample-processed quality metric of the PDCCH and a sample-processed quality metric of the PDSCH. Such sample processed quality metrics may be obtained by various kinds of processing of the samples Xnand Yn, e.g., by filtering. For example, a filtered value can be generated according to: new filtered value = (1- a) * old filtered value + a * new sample value, where a is a filter parameter.

[0065] In a further option, the UE 10 may determine an estimated quality measure at a time t2= t + T to correspond to a last quality measure observed at time tl twhere T is a configuration parameter or a parameter set by standardization.

[0066] In a further option, UE 10 could calculate the correlation metric based on a difference between a given percentile of the quality of the PDCCU and the corresponding percentile of the quality of the PDSCH, as schematically illustrated by Fig. 2: The UE 10 may estimate a percentile of the PDCCH quality, Qc, and a percentile of the PDSCH quality, Qs, and measure the difference between these percentiles: Qc-QsThe percentile can be estimated by storing and sorting historical values or by using an attack / decay-filter, i.e., an exponential moving average that applies different weight depending on the current value is above or below the filter value.

[0067] In a further option, the UE 10 may calculate the correlation metric as the sample covariance of the quality of the PDCCH and the quality of the PDSCH quality. When denoting the sample mean of the quality of the PDCCH by and the sample mean of the quality of the PDSCH by the covariance, Q, of the qualities can be calculated as:

[0068] In some scenarios, the quality of the PDCCH and the quality of the PDSCH can be represented in more than one dimension, e.g., in two dimensions by using both a mean value of the quality and a variance of the quality. In such case, the comparison of the quality of the PDSCH and the quality of the PDCCH may be performed over two dimensions. For example, the UE 10 may construct a two dimensional difference vector where ff2= Z^=i(^n - fc)2. and P110507W001

[0069] - 13 -

[0070] It is noted that any other statistical or analytical method could be used as well to find a distance between the quality distributions of PDSCH and PDCCH.

[0071] As mentioned above. The reporting from the UE 10 to the access node 100 may be based on a reporting rule. Such reporting rule may be configurable, e.g., by RRC configuration. The reporting rule may include a triggering condition or multiple triggering conditions. Further, the reporting rule may define the quantity to be reported. In some cases, the quantity to be reported may be defined per triggering condition.

[0072] According to an option, the triggering condition may be event based: Occurrence of some event based on the correlation metric, e.g., difference in quality of the PDSCH and the PDCCH, may trigger a report. Some examples are as follows:

[0073] In one example, the difference between PDSCH quality and PDCCH quality triggers a report, e.g., the report is triggered if

[0074] PDCCH_quality - PDSCH_quality < threshold.

[0075] The parameter threshold corresponds to a threshold value and may be configurable, e.g., using RRC.

[0076] In a further example, a rank-adjusted PDSCH quality may be used in the comparison, e.g., by triggering the report if

[0077] PDCCH_quality - PDSCH_quality < threshold + rankAdjustedMIMOOffset, where rankAdjustedMIMOOffset is a parameter used to adjust the PDSCH quality of rank 1 MIMO.

[0078] In a further example, the report may be triggered if the covariance of quality of the PDSCH and quality of the PDCCH becomes negative. The negative correlation may indicate that PDSCH quality reports have become unreliable to be used for purposes of PDCCH LA. In a further example, the report may be triggered if the covariance of quality of the PDSCH and quality of the PDCCH changes sign, i.e., transitions from negative to positive or vice versa. In this way, it can be indicated if the PDSCH quality reports have become reliable (covariance goes from negative to positive) or become unreliable (covariance goes from negative to positive). In a further example, the report may be triggered if the covariance of quality of the PDSCH and quality of the PDCCH is less than a threshold. In a further example, the report may be triggered if it is otherwise found out that the quality samples of PDCCH and the PDSCH have become decorrelated. P110507W001

[0079] - 14 -

[0080] In some scenarios, to manage overhead and reduce risk of false alarms, triggering condition may require multiple occurrences of the event(s) before the report is triggered. For example, if the condition

[0081] PDCCH_quality - PDSCH_quality < threshold is met consecutively for M measurement instances, the report is triggered.

[0082] In any of the above examples, SINR values representing the quality of the PDCCH and PDSCH may be mapped to a quantized CQI values and then be compared as explained above. Periodic based. Every T ms or N number of slots the UE triggers a report.

[0083] According to a further option, the report may be sent upon explicit request from network. For example, the access node 100 could explicitly request a report of correlation of quality of the PDCCH and quality of the PDSCH from the UE 10. Such request could for example included in a field in DCI sent to the UE 10. Alternatively, such request could be included in a MAC (Medium Access Control) CE (Control Element) sent to the UE 10.

[0084] In any of the above options, the triggering condition may further require that quality of the PDCCH is below a threshold. Such threshold may be configurable, e.g., using RRC. In this way, overhead may be reduced.

[0085] If the quality is considered in multiple dimensions, e.g., by considering both mean value and variance of the quality, the triggering condition may be based on one of the considered dimensions or a combination of multiple or all of the dimensions. For example, if both conditions < threshold^ and \a - a \ > th.reshold2hold, the report may be triggered. With such multi-dimension triggering condition, statistical differences in the qualities may be detected in an efficient manner. Even though the mean quality of the PDCCH and the PDSCH might be close to each other, the respective variances could differ significantly.

[0086] The report sent by the UE 10 may include various information. In some scenarios, the report may include a binary value which can take two different states: a first state indicating that the quality of the PDSCH quality accurately reflects the quality of the PDCCH or a second state indicating that quality of the PDSCH inaccurately reflects quality of the PDCCH. In some scenarios, the report may include a ternary value which can take three different states: A first state indicating that the quality of the PDSCH quality accurately reflects the quality of the PDCCH quality accurately (or that PDSCH quality reports are reliable for purposes of PDCCH LA), a second state indicating that quality of the PDSCH is significantly better than quality of P110507WQ01

[0087] - 15 - the PDCCH, and a third state indicating that quality of the PDCCH is significantly better than quality of the PDSCH.

[0088] The way of assessing the above criteria by the UE 10 may be made aware to the access node 100. Assessing the criteria may for example be based on the following:

[0089] The quality of the PDSCH accurately reflecting the quality of the PDCCH can be assessed checking if the condition

[0090] | PDSCH_quality - PDCCH_quality | < threshold is met.

[0091] The quality of the PDSCH inaccurately reflecting the quality of the PDCCH can be assessed checking if the condition

[0092] | PDSCH_quality - PDCCH_quality | > threshold is met.

[0093] The quality of the PDSCH being significantly better than the quality of the PDCCH can be assessed checking if the condition

[0094] PDSCH quality - PDCCH quality > threshold? is met.

[0095] The quality of the PDCCH being significantly better than the quality of the PDSCH can be assessed checking if the condition

[0096] PDCCH_quality - PDSCH_quality > thresholds is met.

[0097] In some scenarios, the report could also explicitly include the measured quality of the PDCCH, e.g., in terms of SINR or a value of useful information bits per symbol, per resource element group, or per CCE.

[0098] In some scenarios, the report could also include the correlation metric, e.g., the covariance of the quality of the PDCCH and the quality of the PDSCH.

[0099] In some scenarios, the report could also include a CQI or delta-CQI measure: The report may include CQI values from a certain range of a configured CQI table for PDSCH CQI reporting, which for example indicates the correlation of the quality of the PDCCH and the quality of the P110507W001

[0100] - 16 -

[0101] PDSCH. The report may also include a delta-CQI measure corresponding to the difference between the CQI of the PDSCH and the CQI of the PDCCH.

[0102] In some scenarios, the report could include an explicit or relative interference report. A typical cause of quality difference between the PDCCH and the PDSCH is interference. Accordingly, instead of for example reporting the difference in total quality of PDCCH and PDSCH, it would also be possible to report the difference in interference or an explicit interference estimate for the PDCCH.

[0103] Different options exist for transmitting the report from the UE 10 to the access node 100. The preferred option may also depend on the size of the report. In one option, the report may be transmitted as a dedicated stand-alone message. Such message could be requested by the access node 100 using either a periodic semi-static grant or a dynamic grant. In a further option, the report could be transmitted as part of a dedicated PDSCH CSI report. In a further option, the report could be transmitted together with HARQ (Hybrid Automatic Repeat Request) feedback for a PDSCH transmission.

[0104] Based on the received report, the access node 100 may adjust its PDCCH LA strategy. If the report includes an explicit indication of the quality of the PDCCH, this information can be used as direct input to PDCCH LA. If the report includes the difference in quality of the PDCCH and the PDSCH, the access node 100 may use the reported value of the quality of the PDSCH for PDCCH LA, however with a backoff which is based on the reported difference. If the report indicates that the quality of the PDSCH accurately reflects the quality of the PDCCH, the access node 100 may use reported quality of the PDSCH as input for PDCCH LA. If the report indicates that the quality of the PDSCH inaccurately reflects the quality of the PDCCH, the access node 100 may set PDDCH LA to maximum conservative state, in which there is minimal risk of compromising PDCCH BLER. If the report indicates that quality of the PDSCH is significantly better than quality of the PDCCH, the access node 100 may use the reported value of the quality of the PDSCH for PDCCH LA, however with an increased backoff from the reported quality of the PDSCH to account for the quality difference. If the report indicates that quality of the PDCCH is significantly better than quality of the PDSCH, the access node 100 may use the reported value of the quality of the PDSCH for PDCCH LA, however with a reduced backoff from the reported quality of the PDSCH.

[0105] In addition or as an alternative to adjusting the PDCCH LA strategy, the access node 100 could use the reported information to adjust PDCCH beamforming, e.g., with the aim of increasing P110507W001

[0106] - 17 - the PDCCH SINR. Further, the access node 100 could also use the reported information to decide whether to request explicit PDCCH quality feedback from the UE 10.

[0107] Fig. 3 schematically illustrates an architecture which may be used for implementing the above concepts. In the architecture of Fig. 3, an access node 100 sends DL data via a PDSCH 310 to a UE 10 and sends DCI via a PDCCH 320 to the UE 10. The access node 100 may for example correspond to the access node 100 of Fig. 1 , and the UE 10 may correspond to any of the UEs 10 of Fig. 1.

[0108] The UE 10 includes a first quality estimator 11 which estimates the quality of the PDSCH 310 and a second quality estimator 12 which estimates the quality of the PDCCH 320. Further, the UE 10 includes a correlator 15 which correlates the estimated quality of the PDSCH 310 and the estimated quality of the PDCCH 320. Further, the UE 10 is provided with a reporting engine 16 which receives the results of the correlation of the estimated quality of the PDSCH 310 and the estimated quality of the PDCCH 320. The reporting engine 16 generates reports which are sent to the access node 100. Such reports may for example be generated on the basis of a reporting rule, e.g., as explained above. The access node 100 utilizes the reports as input for PDCCH LA 101. The PDCCH LA may for example operate by adapting the number of CCEs assigned to the PDCCH depending on the reported information.

[0109] Fig. 4 illustrates an example of adaptation processes which are based in the illustrated concepts. In the example of Fig. 4, the processes involve an access node (AN) 100 and a UE 10 wirelessly connected to the access node 100. The access node 100 may for example correspond to the access node 100 of Fig. 1 , and the UE 10 may correspond to any of the UEs 10 of Fig. 1.

[0110] In the processes of Fig. 4, the access node 100 may send configuration information 401 to the UE 10. The configuration information 401 can for example be sent by RRC signaling. The configuration information 401 may be used to configure operation of the UE 10 concerning measurement and reporting of quality of the PDSCH, concerning measurement and reporting of quality of the PDCCH, and / or concerning correlation of the quality of the PDCCH and the quality of the PDSCH and reporting of information related to the correlation, e.g., in terms of a reporting rule.

[0111] As further illustrated, the access node 100 may send DCI 402 to the UE 10. The DCI 402 is sent via the PDCCH. Further, the access node 100 may send DL data 403 to the UE 10. The DL data 403 is sent via the PDSCH. Further, the UE 10 may send UL data 404 to the access P110507W001

[0112] - 18 - node 100. The UL data 404 may for example be sent via a PUSCH. The transmission of the DL data 403 and / or the transmission of the UL data 404 can be scheduled by the DCI 402.

[0113] In accordance with the illustrated concepts, the UE 10 measures quality of the PDSCH and quality of the PDCCH, and correlates the measured qualities. Based on the correlation, the UE 10 sends a report 406 to the access node 100. The report 406 may indicate the correlation of the quality of the PDCCH and the quality of the PDSCH (or a lack of correlation). Further, the report 406 could also indicate the quality of the PDSCH and / or the quality of the PDCCH.

[0114] As indicated by block 407, the access node 100 uses the reported information as input for an adaptation process, e.g., PDCCH link adaptation. Based on the adaptation process, the access node may then again send DCI 408 to the UE 10, e.g., for scheduling a further transmission of DL data 409 or for scheduling a further transmission of UL data 410.

[0115] Fig. 5 schematically illustrates an architecture which may be used for implementing the above concepts. In the architecture of Fig. 5, a first UE 10 (UE1) sends SL data via a PSSCH 510 to a second UE 10 (UE2) and also sends SCI (Sidelink Control Information) via a PSCCH 520 to the second UE 10. The UEs 10 may for example correspond to any of the UEs 10 of Fig. 1 .

[0116] The second UE 10 includes a first quality estimator 13 which estimates the quality of the PSSCH 510 and a second quality estimator 14 which estimates the quality of the PSCCH 520. Further, the second UE 10 includes a correlator 17 which correlates the estimated quality of the PSSCH 510 and the estimated quality of the PSCCH 520. Further, the second UE 10 is provided with a reporting engine 18 which receives the results of the correlation of the estimated quality of the PSSCH 510 and the estimated quality of the PSCCH 520. The reporting engine 18 generates reports which are sent to the first UE 10. Such reports may for example be generated on the basis of a reporting rule, e.g., as explained above. The first UE 10 utilizes the reports as input for PSCCH LA 19.

[0117] Fig. 6 illustrates an example of adaptation processes which are based in the illustrated concepts. In the example of Fig. 6, the processes involve first UE 10 and a second UE 10 engaged in SL communication with the first UE 10. The UEs 10 may for example correspond to any of the UEs 10 of Fig. 1 .

[0118] In the processes of Fig. 6, the first UE 10 may send configuration information 601 to the secpnd UE 10. The configuration information 601 can for example be sent by PC5-RRC signaling. The configuration information 601 may be used to configure operation of the second UE 10 P110507W001

[0119] - 19 - concerning measurement and reporting of quality of the PSSCH, concerning measurement and reporting of quality of the PSCCH, and / or concerning correlation of the quality of the PSCCH and the quality of the PSSCH and reporting of information related to the correlation, e.g., in terms of a reporting rule.

[0120] As further illustrated, the first UE 10 may send SCI 602 to the second UE 10. The SCI 602 is sent via the PSCCH. Further, the first UE 10 may send SL data 603 to the second UE 10. The SL data 603 is sent via the PSSCH. Further, the second UE 10 may send SL data 604 to the first UE 10. The SL data 604 may for example be sent via a PSSCH. The transmission of the SL data 603 and / or the transmission of the SL data 604 can be scheduled by the SCI 602.

[0121] In accordance with the illustrated concepts, the second UE 10 measures quality of the PSSCH and quality of the PSCCH, and correlates the measured qualities. Based on the correlation, the second UE 10 sends a report 606 to the first UE 10. The report 606 may indicate the correlation of the quality of the PSCCH and the quality of the PSSCH (or a lack of correlation). Further, the report 606 could also indicate the quality of the PSSCH and / or the quality of the PSCCH.

[0122] As indicated by block 607, the first UE 10 uses the reported information as input for an adaptation process, e.g., PSCCH link adaptation. Based on the adaptation process, the first UE 10 may then again send SCI 608 to the second UE 10, e.g., for scheduling a further transmission of SL data 609 from the first UE 10 or for scheduling a further transmission of SL data 610 from the second UE 10.

[0123] Fig. 7 shows a flowchart for illustrating a method, which may be utilized for implementing the illustrated concepts. The method of Fig. 7 may be used for implementing the illustrated concepts in a communication device which wirelessly communicates with a further communication device. The communication device may for example correspond to a UE, e.g., to any of the above-mentioned UEs 10, and the further communication device may correspond to a network node, such as the above-mentioned access node 100, or to another UE, such as any of the above-mentioned UEs 10.

[0124] If a processor-based implementation of the communication device is used, at least some of the steps of the method of Fig. 7 may be performed and / or controlled by one or more processors of the communication device. Such communication device may also include a memory storing program code for implementing at least some of the below described functionalities or steps of the method of Fig. 7. P110507W001

[0125] - 20 -

[0126] At step 710, the communication device receives one or more wireless transmissions. The one or more wireless transmissions carry a data channel and a control channel from the further communication device. If the communication device is a UE and the further communication device is a network node, the control channel can be a PDCCH and the data channel a PDSCH, e.g., as in the example of Fig. 3. If the communication device and the further communication device are UEs, the control channel can be a PSCCH and the data channel a PSSCH, e.g., as in the example of Fig. 5.

[0127] At step 720, the communication device determines correlation of quality of the data channel and quality of the control channel.

[0128] At step 730, the communication device sends a report to the further communication device. This is accomplished based on the correlation determined at step 730. The report indicates whether there is a lack of correlation of quality of the control channel and quality of the data channel.

[0129] In some scenarios, the report may include either a first indicator indicating that quality of the data channel may be regarded as being representative of quality of the control channel or a second indicator indicating that quality of the data channel may not be regarded as being representative of quality of the control channel. For example, the report may include a binary value, and the first indicator and the second indicator correspond to two different states of the binary value.

[0130] In some scenarios, the report includes either a third indicator indicating that quality of the data channel may be regarded as being representative of quality of the control channel, a fourth indicator indicating that quality of the data channel is higher than quality of the control channel, or a fifth indicator indicating that quality of the data channel is lower than quality of the control channel. For example, the report may include a ternary value, and the third indicator, the fourth indicator and the fifth indicator correspond to different states of the ternary value.

[0131] In some scenarios, the report may include a metric representing a relation of the quality of the control channel to the quality of the data channel. The metric may represent the relation in terms of difference between the quality of the control channel and the quality of the data channel. Alternatively, the metric could represent the relation in terms of a covariance of the quality of the control channel and the quality of the data channel. P110507W001

[0132] - 21 -

[0133] In some scenarios, the report may include a CQI value indicating whether there is a lack of correlation of the quality of the control channel and the quality of the data channel. In some scenarios, the QQI value may indicates a difference between the quality of the control channel and the quality of the data channel.

[0134] In some scenarios, the report may indicate a difference between interference on the control channel and interference on the data channel.

[0135] In some scenarios, the report may further indicate the quality of the control channel and / or the quality of the data channel.

[0136] In some scenarios, sending of the report may be triggered in response to comparing the quality of the control channel and the quality of the data channel. In some scenarios, sending of the report may be triggered in response to comparing difference between the quality of the control channel and the quality of the data channel to at least one threshold. In some scenarios, sending of the report may be triggered in response to comparing covariance of the quality of the control channel and the quality of the data channel to at least one threshold. In some scenarios, sending of the report may be triggered in response to comparing difference between a mean value of the quality of the control channel and a mean value of the quality of the data channel to at least one first threshold and comparing difference between variance of the quality of the control channel and variance of the quality of the data channel to at least one second threshold.

[0137] In some scenarios, sending of the report may be based on a periodic schedule. In some scenarios, sending of the report is based on a request received by the communication device. In some scenarios, a rule for sending of the report is configured by a node of the wireless communication network. The above-mentioned reporting rule is an example of such network- configurable rule.

[0138] Fig. 8 shows a flowchart for illustrating a method, which may be utilized for implementing the illustrated concepts. The method of Fig. 8 may be used for implementing the illustrated concepts in a communication device which wirelessly communicates with a further communication device. The communication device may for example correspond to a network node, e.g., to the above-mentioned access node 100, or to a UE, e.g., to any of the above- mentioned UEs 10. If the communication device is a network node, such as the above- mentioned access node 100, the further communication device may correspond to a UE, such as the any of the above-mentioned UEs 10. If the communication device is a UE, such as the P110507W001

[0139] - 22 - any of the above-mentioned UEs 10, the further communication device may be another UE, such as any of the above-mentioned UEs 10.

[0140] If a processor-based implementation of the communication device is used, at least some of the steps of the method of Fig. 8 may be performed and / or controlled by one or more processors of the communication device. Such communication device may also include a memory storing program code for implementing at least some of the below described functionalities or steps of the method of Fig. 8.

[0141] At step 810, the communication device sends one or more wireless transmissions. The one or more wireless transmissions carry a data channel and a control channel to the further communication device. If the communication device is a network node and the further communication device is a UE, the control channel can be a PDCCH and the data channel a PDSCH, e.g., as in the example of Fig. 3. If the communication device and the further communication device are UEs, the control channel can be a PSCCH and the data channel a PSSCH, e.g., as in the example of Fig. 5.

[0142] At step 820, the communication device receives a report from the further communication device. The report indicates whether there is a lack of correlation of quality of the control channel and quality of the data channel.

[0143] In some scenarios, the report may include either a first indicator indicating that quality of the data channel may be regarded as being representative of quality of the control channel or a second indicator indicating that quality of the data channel may not be regarded as being representative of quality of the control channel. For example, the report may include a binary value, and the first indicator and the second indicator correspond to two different states of the binary value.

[0144] In some scenarios, the report includes either a third indicator indicating that quality of the data channel may be regarded as being representative of quality of the control channel, a fourth indicator indicating that quality of the data channel is higher than quality of the control channel, or a fifth indicator indicating that quality of the data channel is lower than quality of the control channel. For example, the report may include a ternary value, and the third indicator, the fourth indicator and the fifth indicator correspond to different states of the ternary value.

[0145] In some scenarios, the report may include a metric representing a relation of the quality of the control channel to the quality of the data channel. The metric may represent the relation in P110507W001

[0146] - 23 - terms of difference between the quality of the control channel and the quality of the data channel. Alternatively, the metric could represent the relation in terms of a covariance of the quality of the control channel and the quality of the data channel.

[0147] In some scenarios, the report may include a CQI value indicating whether there is a lack of correlation of the quality of the control channel and the quality of the data channel. In some scenarios, the QQI value may indicates a difference between the quality of the control channel and the quality of the data channel.

[0148] In some scenarios, the report may indicate a difference between interference on the control channel and interference on the data channel.

[0149] In some scenarios, the report may further indicate the quality of the control channel and / or the quality of the data channel.

[0150] In some scenarios, the communication device may configure sending of the report by the further communication device. For example, the communication device may configure the further communication device to send the report in response to comparing the quality of the control channel and the quality of the data channel. Further, the communication device may configure the further communication device to send the report in response to comparing difference between the quality of the control channel and the quality of the data channel to at least one threshold. Further, the communication device may configure the further communication device to send the report in response to comparing covariance of the quality of the control channel and the quality of the data channel to at least one threshold. Further, the communication device may configure the further communication device to send the report in response to comparing difference between a mean value of the quality of the control channel and a mean value of the quality of the data channel to at least one first threshold and comparing difference between variance of the quality of the control channel and variance of the quality of the data channel to at least one second threshold.

[0151] In some scenarios, the communication device may configure the further communication device to send the report based on a periodic schedule. In some scenarios, the communication device may send a request to the further communication device, and sending of the report is based on the request. P110507W001

[0152] - 24 -

[0153] It is noted that at least some the methods of Figs. 7 and 8 could also be combined, e.g., in a system including at least one communication device operating according to the method of Fig. 7 and at least one further communication device operating according to the method of Fig. 8.

[0154] At step 830, the communication device adapts transmission of the control channel. This adaptation is accomplished based on the report received at step 820. The adaptation may for example involve controlling assignment of resource elements, e.g., CCEs, to the control channel. Alternatively or in addition, the adaptation may involve controlling beamforming of the wireless transmissions carrying the control. Further, the adaptation may involve deciding whether to request explicit quality reporting for the control channel.

[0155] Fig. 9 illustrates a processor-based implementation of a wireless device 900 for operation in a wireless communication network, which may be used for implementing the above-described concepts. More specifically, the structures of the wireless device 900 may be used to implement the above-described functionalities in a UE, such as any of the above-mentioned UEs 10.

[0156] As illustrated, the wireless device 900 may include wireless interface 910, which may be used for wireless communication with one or more nodes of the wireless communication network.

[0157] Further, the wireless device 900 may include one or more processors 950 coupled to the interface 910 and a memory 960 coupled to the processor(s) 950. By way of example, the interface 910, the processor(s) 950, and the memory 960 could be coupled by one or more internal bus systems of the wireless device 900. The memory 960 may include a read-only memory (ROM), e.g., a flash ROM, a random-access memory (RAM), e.g., a dynamic RAM (DRAM) or static RAM (SRAM), a mass storage, e.g., a hard disk or solid state disk, or the like. As illustrated, the memory 960 may include software 970 and / or firmware 980. The memory 960 may include suitably configured program code to be executed by the processor(s) 950 so as to implement or configure the above-described functionalities for wireless communication, such as explained in connection with Fig. 7 or 8.

[0158] It is to be understood that the structures as illustrated in Fig. 9 are merely schematic and that the wireless device 900 may actually include further components which, for the sake of clarity, have not been illustrated, e.g., further interfaces or further processors. Also, it is to be understood that the memory 960 may include further program code for implementing known functionalities of a UE in a 3GPP system. According to some embodiments, also a computer program may be provided for implementing functionalities of the wireless device 900, e.g., in P110507W001

[0159] - 25 - the form of a physical medium storing the program code and / or other data to be stored in the memory 960 or by making the program code available for download or by streaming.

[0160] Fig. 10 illustrates a processor-based implementation of a network node 1000 for operation in a wireless communication network, which may be used for implementing the above-described concepts. More specifically, the structures of the network node 1000 may be used to implement the above-described functionalities in a radio access node, such as the above-mentioned access node 100.

[0161] As illustrated, the network node 1000 may include wireless interface 1010, which may be used for wireless communication with one or more wireless devices, such as the above-mentioned UEs 10. Further, the network node 1000 may include a network interface 1020, which may be used for communication with other network nodes.

[0162] Further, the network node 1000 may include one or more processors 1050 coupled to the interfaces 1010, 1020 and a memory 1060 coupled to the processor(s) 1050. By way of example, the interfaces 1010, 1020, the processor(s) 1050, and the memory 1060 could be coupled by one or more internal bus systems of the network node 1000. The memory 1060 may include a ROM, e.g., a flash ROM, a RAM, e.g., a DRAM or SRAM, a mass storage, e.g., a hard disk or solid state disk, or the like. As illustrated, the memory 1060 may include software 1070 and / or firmware 1080. The memory 1060 may include suitably configured program code to be executed by the processor(s) 1050 so as to implement or configure the above-described functionalities for wireless communication, such as explained in connection with Fig. 7 or 8.

[0163] It is to be understood that the structures as illustrated in Fig. 10 are merely schematic and that the network node 1000 may actually include further components which, for the sake of clarity, have not been illustrated, e.g., further interfaces or further processors. Also, it is to be understood that the memory 1060 may include further program code for implementing known functionalities of a radio access node in a 3GPP system. According to some embodiments, also a computer program may be provided for implementing functionalities of the network node 1000, e.g., in the form of a physical medium storing the program code and / or other data to be stored in the memory 1060 or by making the program code available for download or by streaming.

[0164] As can be seen, the concepts as described above may be used for efficiently considering possible mismatch of quality of a data channel and quality of a related control channel, such as quality of the PDSCH and quality of the PDCCH or quality of the PSSCH and quality of the P110507W001

[0165] - 26 -

[0166] PSCCH. By providing reports based on correlation of the qualities, for example link adaptation of the control channel may be performed in an efficient manner. As a result, efficiency of resource utilization and / or performance of the control channel can be improved. It is to be understood that the examples and embodiments as explained above are merely illustrative and susceptible to various modifications. For example, the illustrated concepts may be applied to various types of wireless transmissions, conveying data of various services. Further, the illustrated concepts may be applied in connection with various kinds of wireless communication technologies, also including modifications or enhancements of the 4G LTE technology or of the 5G NR technology. Moreover, it is to be understood that the above concepts may be implemented by using correspondingly designed software to be executed by one or more processors of an existing device or apparatus, or by using dedicated device hardware. Further, it should be noted that the illustrated apparatuses or devices may each be implemented as a single device or as a system of multiple interacting devices or modules.

Claims

P110507W001- 27 -Claims1. A method of controlling wireless communication in a wireless communication network, the method comprising: a communication device (10; 100; 900; 1000) receiving one or more wireless transmissions carrying a data channel (310; 510) and a control channel (320; 520) from a further communication device (10; 100; 900; 1000); the communication device (10; 100; 900; 1000) determining correlation of quality of the data channel (310; 510) and quality of the control channel (320; 520); and based on the determined correlation, the communication device (10; 100; 900; 1000) sending a report (406; 606) to the further communication device (10; 100; 900; 1000), the report (406; 606) indicating whether there is a lack of correlation of quality of the control channel (320; 520) and quality of the data channel (310; 510).

2. The method according to claim 1 , wherein the report (406; 606) comprises either a first indicator indicating that quality of the data channel (310; 510) may be regarded as being representative of quality of the control channel (320; 520) or a second indicator indicating that quality of the data channel (310; 510) may not be regarded as being representative of quality of the control channel (320; 520).

3. The method according to claim 2, wherein the report (406; 606) comprises a binary value and the first indicator and the second indicator correspond to two different states of the binary value.

4. The method according to any of the preceding claims, wherein the report (406; 606) comprises either a third indicator indicating that quality of the data channel (310; 510) may be regarded as being representative of quality of the control channel (320; 520), a fourth indicator indicating that quality of the data channel (310; 510) is higher than quality of the control channel (320; 520), or a fifth indicator indicating that quality of the data channel (310; 510) is lower than quality of the control channel (320; 520).

5. The method according to claim 4, wherein the report (406; 606) comprises a ternary value and the third indicator, the fourth indicator and the fifth indicator correspond to different states of the ternary value.

6. The method according to any of the preceding claims,P110507W001- 28 - wherein the report (406; 606) comprises a metric representing a relation of the quality of the control channel (320; 520) to the quality of the data channel (310; 510).

7. The method according to claim 6, wherein the metric represents the relation in terms of difference between the quality of the control channel (320; 520) and the quality of the data channel (310; 510).

8. The method according to claim 6, wherein the metric represents the relation in terms of a covariance of the quality of the control channel (320; 520) and the quality of the data channel (310; 510).

9. The method according to any of the preceding claims, wherein the report (406; 606) comprises a Channel Quality Indicator, CQI, value indicating whether there is a lack of correlation of the quality of the control channel (320; 520) and the quality of the data channel (310; 510).

10. The method according to claim 9, wherein the QQI value indicates a difference between the quality of the control channel (320; 520) and the quality of the data channel (310; 510).11 . The method according to any of the preceding claims, wherein the report (406; 606) indicates a difference between interference on the control channel (320; 520) and interference on the data channel (310; 510).

12. The method according to any of the preceding claims, wherein the report (406; 606) further indicates the quality of the control channel (320; 520).

13. The method according to any of the preceding claims, wherein the report (406; 606) further indicates the quality of the data channel (310; 510).

14. The method according to any of the preceding claims, wherein sending of the report (406; 606) is triggered in response to comparing the quality of the control channel (320; 520) and the quality of the data channel (310; 510).

15. The method according to claim 14,P110507W001- 29 - wherein sending of the report (406; 606) is triggered in response to comparing difference between the quality of the control channel (320; 520) and the quality of the data channel (310; 510) to at least one threshold.

16. The method according to any of the preceding claims, wherein sending of the report (406; 606) is triggered in response to comparing covariance of the quality of the control channel (320; 520) and the quality of the data channel (310; 510) to at least one threshold.

17. The method according to any of the preceding claims, wherein sending of the report (406; 606) is triggered in response to comparing difference between a mean value of the quality of the control channel (320; 520) and a mean value of the quality of the data channel (310; 510) to at least one first threshold and comparing difference between variance of the quality of the control channel (320; 520) and variance of the quality of the data channel (310; 510) to at least one second threshold.

18. The method according to any of the preceding claims, wherein sending of the report (406; 606) is based on a periodic schedule.

19. The method according to any of the preceding claims, wherein sending of the report (406; 606) is based on a request received by the communication device.

20. The method according to any of the preceding claims, wherein a rule for sending of the report (406; 606) is configured by a node (100; 1000) of the wireless communication network.

21. The method according to any of the preceding claims, wherein the communication device (10; 900) is a user equipment, UE; and the further communication device (100; 1000) is a radio access node of the wireless communication network, and wherein the control channel (320) is a Physical Downlink Control Channel, PDCCH, and the data channel (310) is a Physical Downlink Shared Channel, PDSCH.

22. A method of controlling wireless communication in a wireless communication network, the method comprising:P110507W001- 30 - a communication device (10; 100; 900; 1000) sending one or more wireless transmissions carrying a data channel (310; 510) and a control channel (320; 520) to a further communication device (10; 900); the communication device (10; 100; 900; 1000) receiving a report (406; 606) from the further communication device (10; 900), the report (406; 606) indicating whether there is a lack of correlation of quality of the control channel (320; 520) and quality of the data channel (310; 510); and based on the report (406; 606), the communication device (10; 100; 900; 1000) adapting transmission of the control channel (320; 520).

23. The method according to claim 22, wherein the report (406; 606) comprises either a first indicator indicating that quality of the data channel (310; 510) may be regarded as being representative of quality of the control channel (320; 520) or a second indicator indicating that quality of the data channel (310; 510) may not be regarded as being representative of quality of the control channel (320; 520).

24. The method according to claim 23, wherein the report (406; 606) comprises a binary value and the first indicator and the second indicator correspond to two different states of the binary value.

25. The method according to any of claims 22 to 24, wherein the report (406; 606) comprises either a third indicator indicating that quality of the data channel (310; 510) may be regarded as being representative of quality of the control channel (320; 520), a fourth indicator indicating that quality of the data channel (310; 510) is higher than quality of the control channel (320; 520), or a fifth indicator indicating that quality of the data channel (310; 510) is lower than quality of the control channel (320; 520).

26. The method according to claim 25, wherein the report (406; 606) comprises a ternary value and the third indicator, the fourth indicator and the fifth indicator correspond to different states of the ternary value.

27. The method according to any of claims 22 to 26, wherein the report (406; 606) comprises a metric representing a relation of the quality of the control channel (320; 520) to the quality of the data channel (310; 510).

28. The method according to claim 27,P110507W001- 31 - wherein the metric represents the relation in terms of difference between the quality of the control channel (320; 520) and the quality of the data channel (310; 510).

29. The method according to claim 27, wherein the metric represents the relation in terms of a covariance of the quality of the control channel (320; 520) and the quality of the data channel (310; 510).

30. The method according to any of claims 22 to 29, wherein the report (406; 606) comprises a Channel Quality Indicator, QQI, value indicating whether there is a lack of correlation of the quality of the control channel (320; 520) and the quality of the data channel (310; 510).

31. The method according to claim 30, wherein the QQI value indicates a difference between the quality of the control channel (320; 520) and the quality of the data channel (310; 510).

32. The method according to any of claims 22 to 31 , wherein the report (406; 606) indicates a difference between interference on the control channel (320; 520) and interference on the data channel (310; 510).

33. The method according to any of claims 22 to 32, wherein the report (406; 606) further indicates the quality of the control channel (320; 520).

34. The method according to any of claims 22 to 33, wherein the report (406; 606) further indicates the quality of the data channel (310; 510).

35. The method according to any of claims 22 to 34, comprising: the communication device (10; 100; 900; 1000) configuring sending of the report (406; 606) by the further communication device (10; 900).

36. The method according to claim 34, comprising: the communication device (10; 100; 900; 1000) configuring the further communication device (10; 900) to send the report (406; 606) in response to comparing the quality of the control channel (320; 520) and the quality of the data channel (310; 510).

37. The method according to claim 35 or 36, comprising:P110507W001- 32 - the communication device (10; 100; 900; 1000) configuring the further communication device (10; 900) to send the report (406; 606) in response to comparing difference between the quality of the control channel (320; 520) and the quality of the data channel (310; 510) to at least one threshold.

38. The method according to any of claims 35 to 37, comprising: the communication device (10; 100; 900; 1000) configuring the further communication device (10; 900) to send the report (406; 606) in response to comparing covariance of the quality of the control channel (320; 520) and the quality of the data channel (310; 510) to at least one threshold.

39. The method according to any of claims 35 to 38, comprising: the communication device (10; 100; 900; 1000) configuring the further communication device (10; 900) to send the report (406; 606) in response to comparing difference between a mean value of the quality of the control channel (320; 520) and a mean value of the quality of the data channel (310; 510) to at least one first threshold and comparing difference between variance of the quality of the control channel (320; 520) and variance of the quality of the data channel (310; 510) to at least one second threshold.

40. The method according to any of claims 35 to 39, comprising: the communication device (10; 100; 900; 1000) configuring the further communication device (10; 900) to send the report (406; 606) based on a periodic schedule.41 . The method according to aby of claims 35 to 40, comprising: the communication device (10; 100; 900; 1000) sending a request to the further communication device (10; 900), wherein sending of the report (406; 606) is based on the request.

42. The method according to any of claims 22 to 41 , wherein the communication device (10; 900) is a user equipment, UE; and the further communication device (100; 1000) is a radio access node of the wireless communication network, and wherein the control channel (320) is a Physical Downlink Control Channel, PDCCH, and the data channel (310) is a Physical Downlink Shared Channel, PDSCH.

43. A communication device (10; 100; 900; 1000), the communication device (10; 100; 900; 1000) being configured to:P110507W001- 33 - receive one or more wireless transmissions carrying a data channel (310; 510) and a control channel (320; 520) from a further communication device (10; 100; 900; 1000); determine correlation of quality of the data channel (310; 510) and quality of the control channel (320; 520); and based on the determined correlation, send a report (406; 606) to the further communication device (10; 100; 900; 1000), the report (406; 606) indicating whether there is a lack of correlation of quality of the control channel (320; 520) and quality of the data channel (310; 510).

44. The communication device according to claim 43, wherein the communication device (10; 100; 900; 1000) is configured to perform a method according to any of claims 2 to 21 .

45. The communication device (10; 100; 900; 1000) according to claim 43 or 44, comprising: at least one processor (950; 1050), and a memory (960; 1060) containing program code executable by the at least one processor (950; 1050), whereby execution of the program code by the at least one processor (950; 1050) causes the communication device (10; 100; 900; 1000) to perform a method according to any of claims 1 to 21.

46. A communication device (10; 100; 900; 1000), the communication device (10; 100; 900; 1000) being configured to: send one or more wireless transmissions carrying a data channel (310; 510) and a control channel (320; 520) to a further communication device (10; 900); receive a report (406; 606) from the further communication device (10; 900), the report (406; 606) indicating whether there is a lack of correlation of quality of the control channel (320; 520)and quality of the data channel (310; 510); and based on the report (406; 606), adapt transmission of the control channel (320; 520).

47. The communication device (10; 100; 900; 1000) according to claim 46, wherein the communication device (10; 100; 900; 1000) is configured to perform a method according to any of claims 23 to 42.

48. The communication device (10; 100; 900; 1000) according to claim 46 or 47, comprising: at least one processor (950; 1050), andP110507W001- 34 - a memory (960; 1060) containing program code executable by the at least one processor (950;1050), whereby execution of the program code by the at least one processor (950; 1050) causes the communication device (10; 100; 900; 1000) to perform a method according to any of claims 22 to 42.

49. A computer program or computer program product comprising program code to be executed by at least one processor (950; 1050) of a communication device (10; 100; 900; 1000), whereby execution of the program code causes the communication device (10; 100; 900; 1000) to perform a method according to any one of claims 1 to 42.

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