Energy efficient network antenna port adaptation

Abstract

A User Equipment, UE (30), receives, from a network node (20), a plurality of Channel State Information Reference Signal, CSI-RS, resource configurations that overlap on at least one time / frequency resource and use the same Code Division Multiplexing, CDM, type. Each CSI-RS resource configuration corresponds to a respective antenna port. The UE (30) receives, from the network node (20), a request to perform CSI-RS measurements on one or more of the antenna ports. The UE (30) measures each of the one or more antenna ports in accordance with the corresponding CSI-RS resource configuration. The UE (30) transmits, to the network node (20), one or more measurement reports comprising one or more results of the measuring.

Description

[0001] ENERGY EFFICIENT NETWORK ANTENNA PORT ADAPTATION

[0002] TECHNICAL FIELD

[0003] Embodiments of the present disclosure generally relate to wireless communication networks, and particularly relates to adapting network antenna configuration, e.g., in order to balance performance and power consumption concerns.

[0004] BACKGROUND

[0005] NW energy savings in NR is generally considered to be of great importance not only as part of reducing operating expenses for operators but also for environmental sustainability to reduce environmental impact. A major part of the consumed energy in NR is related to the increased number of TX / RX antenna ports especially at higher frequencies. For efficient beam management, this also results in a higher number of reference signal transmissions such as CSI-RSs which in turn, due to excessive number of radio wakeups, is quite energy consuming. The energy cost associated with RF components (e.g., power amplifiers, low noise amplifiers), digital processing (e.g. digital front end, beamforming), and baseband processing associated with such an array is high. In some scenarios (e.g., few users, low load, reduced user throughput or latency requirements), maintaining sufficient user and system performance may not require the full gNB antenna array. The gNB may then deactivate or mute parts of the antenna panel and transmit with a subset of the antenna elements and transmission ports. Which part of the array is muted depends on different deployments, loads, and UE coverage scenarios and therefore the gNB may dynamically adapt the muting pattern. There is also a tradeoff between energy saving gains and UE performance loss.

[0006] SUMMARY

[0007] The present disclosure is generally directed to adapting antenna utilization in a way that balances performance and power consumption concerns. Particular embodiments include a method, implemented by a UE. The method comprises receiving, from a network node, a plurality of CSI-RS resource configurations that overlap on at least one time / frequency resource and use the same CDM type. Each CSI-RS resource configuration corresponds to a respective antenna port. The method further comprises receiving, from the network node, a request to perform CSI-RS measurements on one or more of the antenna ports. The method further comprises measuring each of the one or more antenna ports in accordance with the corresponding CSI-RS resource configuration. The method further comprises transmitting, to the network node, one or more measurement reports comprising one or more results of the measuring.

[0008] In some embodiments, receiving the plurality of CSI-RS resource configurations comprises receiving an Information Element, IE, describing a first CSI-RS resource configuration.

[0009] In some embodiments, receiving the plurality of CSI-RS resource configurations comprises receiving an IE describing a second CSI-RS resource configuration.

[0010] In some embodiments, receiving the plurality of CSI-RS resource configurations comprises receiving a multi-port CSI-RS configuration comprising the plurality of CSI-RS resource configurations. In some such embodiments, the multi-port CSI-RS configuration further comprises port number remapping information. In some such embodiments, the port number remapping information comprises a codebook or codebook index. Additionally or alternatively, the multiport CSI-RS configuration may further comprise one or more CSI-RS to Physical Downlink Shared Channel, PDSCH, offset values.

[0011] In some embodiments, the request to perform the CSI-RS measurements is comprised in Layer 2 signaling. In some such embodiments, the request to perform the CSI-RS measurements is comprised in a Medium Access Control, MAC, Control Element, CE of the Layer 2 signaling.

[0012] In some embodiments, the request to perform the CSI-RS measurements is comprised in Layer 1 signaling. In some such embodiments, the request to perform the CSI-RS measurements is comprised in Downlink Control Information, DCI, of the Layer 1 signaling.

[0013] In some embodiments, the request to perform the CSI-RS measurements comprises a CDM group to measure. In some other embodiments, the request to perform the CSI-RS measurements comprises reference to one or more of the CSI-RS resource configurations.

[0014] In some embodiments, the request to perform the CSI-RS measurements comprises a bitfield indicating the one or more of the antenna ports to measure.

[0015] In some embodiments, the method further comprises receiving, from the network node, a Transmission Configuration Indicator, TCI, state change in response to transmitting the one or more measurement reports.

[0016] Other embodiments include a UE. The UE comprises interface circuitry and processing circuitry communicatively connected to the interface circuitry. The processing circuitry is configured to receive, from a network node and via the interface circuitry, a plurality of CSI-RS resource configurations that overlap on at least one time / frequency resource and use the same CDM type. Each CSI-RS resource configuration corresponds to a respective antenna port. The processing circuitry is further configured to receive, from the network node, a request to perform CSI-RS measurements on one or more of the antenna ports. The processing circuitry is further configured to measure each of the one or more antenna ports in accordance with the corresponding CSI-RS resource configuration. The processing circuitry is further configured to transmit, to the network node and via the interface circuitry, one or more measurement reports comprising one or more results of the measuring.

[0017] In some embodiments, the processing circuitry is further configured to perform any one of the methods described above.

[0018] Other embodiments include a computer program comprising instructions that, when executed on processing circuitry of a UE, cause the UE to carry out any one of the methods described above. Yet other embodiments include a carrier containing said computer program. The carrier is one of an electronic signal, optical signal, radio signal, or computer readable storage medium.

[0019] Other embodiments include a method implemented by a network node. The method comprises providing, to a UE, a plurality of CSI-RS resource configurations that overlap on at least one time / frequency resource and use the same CDM type. Each CSI-RS resource configuration corresponds to a respective antenna port. The method further comprises transmitting, to the UE, a request to perform CSI-RS measurements on one or more of the antenna ports. The method further comprises receiving, from the UE, one or more measurement reports of the one or more antenna ports, each antenna port measured in accordance with the corresponding CSI-RS resource configuration. The method further comprises switching one or more antennas of the network node between muted and unmuted based on the one or more reports.

[0020] In some embodiments, providing the plurality of CSI-RS resource configurations comprises transmitting an IE describing a first CSI-RS resource configuration.

[0021] In some embodiments, providing the plurality of CSI-RS resource configurations comprises transmitting an IE describing a second CSI-RS resource configuration.

[0022] In some embodiments, providing the plurality of CSI-RS resource configurations comprises transmitting a multi-port CSI-RS configuration comprising the plurality of CSI-RS resource configurations.

[0023] In some embodiments, the multi-port CSI-RS configuration further comprises port number remapping information. In some such embodiments, the port number remapping information comprises a codebook or codebook index. Additionally or alternatively, the multi-port CSI-RS configuration may further comprise one or more CSI-RS to PDSCH offset values.

[0024] In some embodiments, the method further comprises adapting transmission power based on the one or more reports. In some embodiments, switching the one or more antennas between muted and unmuted is further based on a service quality requirement. In some such embodiments, the service quality requirement is comprised in an SLA. In some other embodiments, the service quality requirement is comprised in a QoS agreement.

[0025] In some embodiments, the request to perform the CSI-RS measurements is comprised in Layer 2 signaling. In some such embodiments, the request to perform the CSI-RS measurements is comprised in a MAC CE of the Layer 2 signaling.

[0026] In some embodiments, the request to perform the CSI-RS measurements is comprised in Layer 1 signaling. In some such embodiments, the request to perform the CSI-RS measurements is comprised in DCI of the Layer 1 signaling.

[0027] In some embodiments, the request to perform the CSI-RS measurements comprises a CDM group to measure.

[0028] In some embodiments, the request to perform the CSI-RS measurements comprises reference to one or more of the CSI-RS resource configurations.

[0029] In some embodiments, the request to perform the CSI-RS measurements comprises a bitfield indicating the one or more of the antenna ports to measure.

[0030] In some embodiments, switching the one or more antennas of the network node between muted and unmuted is further based on at least one further report from another UE.

[0031] In some embodiments, switching the one or more antennas of the network node between muted and unmuted is further based on a type of transmission to be performed.

[0032] In some embodiments, switching the one or more antennas of the network node between muted and unmuted comprises switching at least one antenna port between muted and unmuted.

[0033] In some embodiments, the method further comprises informing the UE of a TCI state change in response to switching the one or more antennas between muted and unmuted. Other embodiments include a network node. The network node comprises interface circuitry and processing circuitry communicatively connected to the interface circuitry. The processing circuitry is configured to provide, to a UE via the interface circuitry, a plurality of CSI-RS resource configurations that overlap on at least one time / frequency resource and use the same CDM type. Each CSI-RS resource configuration corresponds to a respective antenna port. The processing circuitry is further configured to transmit, to the UE via the interface circuitry, a request to perform CSI-RS measurements on one or more of the antenna ports. The processing circuitry is further configured to receive, from the UE via the interface circuitry, one or more measurement reports of the one or more antenna ports, each antenna port measured in accordance with the corresponding CSI-RS resource configuration. The processing circuitry is further configured to switch one or more antennas of the network node between muted and unmuted based on the one or more reports.

[0034] In some embodiments, the processing circuitry is further configured to perform any one of the network node methods described above.

[0035] Other embodiments include a computer program comprising instructions that, when executed on processing circuitry of a network node, cause the network node to carry out any one of the network node methods described above.

[0036] Yet other embodiments include a carrier containing said computer program. The carrier is one of an electronic signal, optical signal, radio signal, or computer readable storage medium.

[0037] BRIEF DESCRIPTION OF THE FIGURES

[0038] Aspects of the present disclosure are illustrated by way of example and are not limited by the accompanying figures with like references indicating like elements. All abbreviations used in this disclosure, including those used in the figures, can be found defined in the subsection entitled “Abbreviations” toward the end of the detailed description. Figures 1A-1 D are schematic diagrams illustrating different examples of CSI-RS resource allocations within a grid of time-frequency resources, according to various embodiments of the present disclosure.

[0039] Figure 2 is a table describing example triggering / activation characteristics of CSI reporting for different CSI-RS configurations, according to one or more embodiments of the present disclosure.

[0040] Figures 3A-3D are schematic diagrams illustrating different examples of antenna utilization when different antenna ports are active, according to one or more embodiments of the present disclosure.

[0041] Figure 4 is a schematic diagram illustrating an example wireless communication network, according to one or more embodiments of the present disclosure.

[0042] Figure 5 is a flow diagram illustrating an example method implemented by a network node, according to one or more embodiments of the present disclosure.

[0043] Figure 6 is a flow diagram illustrating an example method implemented by a UE, according to one or more embodiments of the present disclosure.

[0044] Figure 7 is a flow diagram illustrating another example method implemented by a network node, according to one or more embodiments of the present disclosure.

[0045] Figure 8 is a schematic diagram illustrating an example of CDM groups of CSI-RS resources, according to one or more embodiments of the present disclosure.

[0046] Figure 9 is a schematic diagram illustrating an example of separating the CSI-RSs of a CDM group, according to one or more embodiments of the present disclosure.

[0047] Figure 10 is a table illustrating example values for separating CSI-RSs using CDM, according to one or more embodiments of the present disclosure.

[0048] Figure 11 is a table illustrating example values for identifying CSI-RS locations within a slot based on numerous factors, according to one or more embodiments of the present disclosure. Figure 12 is a schematic block diagram illustrating an example of different antenna arrangements, according to one or more embodiments of the present disclosure.

[0049] Figure 13 is a flow diagram illustrating another example method implemented by a UE, according to one or more embodiments of the present disclosure.

[0050] Figure 14 is a schematic block diagram illustrating an example UE, according to one or more embodiments of the present disclosure.

[0051] Figure 15 is a schematic block diagram illustrating an example RAN node, according to one or more embodiments of the present disclosure.

[0052] Figure 16 is a schematic block diagram illustrating an example of a communication system in accordance with some embodiments.

[0053] Figure 17 is a schematic block diagram illustrating an example host, according to one or more embodiments of the present disclosure.

[0054] Figure 18 is a schematic block diagram illustrating an example network, according to one or more embodiments of the present disclosure.

[0055] DETAILED DESCRIPTION

[0056] NW power consumption for NR is said to be less compared to LTE because of its relatively lean design. In current implementations, however, NR can in many situations consume more power compared to LTE, e.g., due to the higher bandwidth and even more so due to introduction of additional elements such as 64 TX / RX ports with associated digital RF chains. As the NW is expected to be able to support a UE at its maximum capabilities (e.g., throughput, coverage, etc.), the NW may need to use a full configuration even when the maximum NW support is rarely needed by UEs.

[0057] In addition, an increased number of TX / RX ports also leads to an increase of the number of reference signals (e.g., CSI-RS) traditionally needed to be transmitted by the NW (and to be measured by the UE) for a proper signal detection. Thus, the additional TX / RX ports may result in another way in which additional power is consumed, i.e. , to transmit a larger number of CSI-RS to the UEs. Furthermore, it should also be noted that the larger number of CSI-RS transmissions may also consume valuable NW resources as well as generate increased interference to neighboring cells.

[0058] A CSI-RS resource may span 1 , 2, or 4 OFDM symbols. One symbol is used for 1 , 2, 4, 8, or 12 ports, e.g., as shown in the time-frequency resource grid of Figure 1A. Two symbols are used for 4, 8, 12, or 16 ports, e.g., as shown in the time-frequency resource grid of Figure 1 B. Four symbols for 24 or 32 ports, e.g., as shown in the time-frequency resource grid of Figure 1 C (which illustrates an adjacent allocation) or as shown in the time-frequency resource grid of Figure 1 D (which illustrates a pairwise adjacent allocation).

[0059] In the time-frequency resource grids of Figures 1A-1 D, time (in symbol units) is on the x-axis and frequency is on the y-axis. Resources that are similarly shaded in Figures 1A-1 D indicate resources belonging to the same CDM group. The different CSI-RSs carried within the same CDM group may be separated using CDM. Each CDM group may support a plurality of antenna ports.

[0060] A CSI-RS resource may start at any symbol within a slot (e.g., any of symbols 0-13 for slots that have a normal cyclic prefix, as show in Figures 1A- 1 D) defined by a single start symbol (for 1 symbol CSI-RS, 2 symbol CSI-RS, and 4 symbols with OCC span 4) or defined by two start symbol indices (in the 4 symbol CSI-RS 2+2 with OCC span 2). Components may be mapped to frequency with a granularity of component size, 1 , 2, or 4 subcarriers. The same subcarriers are used across all symbols in a resource.

[0061] In NR, three types of CSI-RS transmissions are traditionally supported, namely aperiodic, periodic, and semi-persistent. Aperiodic CSI-RS transmission is a one-shot CSI-RS transmission that can be triggered by a gNB via DCI in any slot. In this instance, the term “one-shot” means that CSI-RS transmission only happens once per trigger in one slot. The CSI-RS resources (i.e., the resource element locations which consist of subcarrier locations and OFDM symbol locations) for aperiodic CSI-RS are preconfigured to UEs via higher layer signaling. The transmission of aperiodic CSI-RS is triggered via DCI. Figure 2 is a table describing triggering / activation characteristics of CSI reporting for different CSI-RS configurations. As shown in the table of Figure 2, aperiodic CSI-RS can be used for aperiodic CSI reporting.

[0062] Periodic CSI-RS transmission is preconfigured by higher layer signaling and the pre-configuration includes parameters such as periodicity and slot offset. Periodic CSI-RS is traditionally controlled by higher layer signaling only. Traditionally, the periodic CSI-RS transmission starts following RRC configuration following the configured parameters. As shown in Figure 2, periodic CSI-RS can be used for periodic CSI reporting, semi-persistent CSI reporting, and aperiodic CSI reporting.

[0063] Semi-persistent CSI-RS transmission is similar to periodic CSI-RS in certain respects. Resources for semi-persistent CSI-RS transmissions are preconfigured via higher layer signaling with parameters such as periodicity and slot offset. However, unlike periodic CSI-RS, a dynamic allocation activation signaling via a MAC CE is needed to begin transmission of semi-persistent CSI- RS on the preconfigured resources. Furthermore, semi-persistent CSI-RS is transmitted for a limited time duration until the activated semi-persistent CSI-RS is deactivated via a deactivation signaling via a MAC CE. As shown in Figure 2, semi-persistent CSI-RS can be used for semi-persistent CSI reporting and aperiodic CSI reporting.

[0064] Typically, there is a tradeoff between energy saving gains and UE performance loss. In traditional solutions, the gNB has no way to know in advance what the impact of a decision to change the number of active antenna ports will be. When switching down (e.g., to reduce energy consumption) there is a risk that the impact to UE performance will be unacceptable. When switching up (e.g., to increase UE performance and / or cell capacity) there is a risk that the only effect will be increased network energy consumption with a negligible improvement of UE performance. The decision to change antenna configuration from, e.g., 64 active antenna elements down to 32, 16, or 8 active antenna elements is often traditionally done by trial and error. Similarly, when switching the gNB antenna configuration up from a lower configuration (e.g., with 32, 16, or 8 active antennas) to a higher configuration (e.g., with 64 active antennas) there is currently a risk that the result will only be increased network energy consumption without any relevant increase in UE throughput.

[0065] Traditionally, it is only after an antenna configuration switch that the gNB can observe what happened and evaluate whether the decision to switch was good or bad. Unfortunately, if it was a bad decision (e.g., the UE performance impact was not acceptable), then damage has already been done without adequate improvement to the performance versus energy tradeoff. This may result in recurrent reconfigurations (e.g., the antenna adaptation algorithm may try to change configuration too often) or missed opportunities for energy savings (e.g., the antenna adaptation algorithm may be too rigid).

[0066] To avoid recurrent reconfigurations and excessive UE performance loss caused by transceiver muting, it would be advantageous for the gNB to acquire knowledge of what performance would result from the different muting patterns prior to the actual transceiver muting decision. This might be enabled, for example, if the UE reports not only CSI for the current transceiver configuration (e.g., 64 chains), but also CSI for other candidate configuration(s) (e.g., 32, 16, or 8).

[0067] When it comes to CSI-RS transmission, irrespective of the number of physical antenna subarrays, 3GPP has defined up to 32 CSI-RS antenna ports where each port is mapped to a group of physical sub-arrays. According to the current specifications, it is possible to configure the UE with multiple CSI-RS set configurations corresponding to the different transceiver muting layouts and ask the UE to report the CSI for the different configurations. For example, besides configuring a 32-ports CSI-RS resource which is transmitted from a full panel incorporating all transceiver chains, the gNB can also configure the UE with a 16- ports CSI-RS resource which is transmitted from half of the panel. The gNB can then get CSI feedbacks for both 32 ports (full panel) and 16 ports (half panel) and derive the impact on UE performance in case half of the panel is turned off and whether it is suitable to do so.

[0068] The issue with configuring the UE with multiple CSI-RS resources employing different numbers of ports is that it will result in considerable overhead both in terms of gNB energy consumption caused by extra transmissions and resource wastage because of extra time / frequency resource occupation. Furthermore, the UE CSI-RS measurement effort increases for each of these configurations. Note that the examples above only addressed full vs half panel configurations, whereas in reality there could be other port constellations / layouts / subsets (e.g., as shown in the examples of Figures 3A-3D) that are of interest as well and which would contribute to even more CSI-RS configurations and potentially exceed UE capabilities. In each of the Figures 3A- 3D, a darker X represents an antenna port that is included in a configuration and a lighter X represents an antenna port this is excluded from the configuration.

[0069] If limiting the configuration to a single CSI-RS resource set at a time, RRC reconfigurations are currently possible, however they entail a large signaling overhead and are quite slow for both the network and the UE.

[0070] One potential solution includes multiple port subset hypotheses being defined and linked to the currently active CSI-RS resource. Each hypothesis would determine a selection of subsets of configured CSI-RS ports (how many and which) to measure and at which rate. The hypotheses could be configured by RRC or other higher layer signaling, and MAC CE or DCI may be used to select a subset of hypotheses from the complete set. However, such a solution does not consider the overhead due to possibly non-overlapping resources and focuses primarily on finding desirable reduced configurations without facilitating identification of possible extended configurations compared to a current reduced active port subset.

[0071] Another potential solution includes a UE that is configured with a number of CSI-RS ports to measure and reporting is further configured with one or more port muting patterns. During operation, the UE may receive signaling (e.g., DCI or MAC CE) indicating whether and which port muting pattern is in effect. The UE may then omit measuring / processing CSI-RS resources corresponding to the muted ports, which may include omitting sampling CSI-RS symbols that carry only muted ports and omitting related estimation processing in the baseband. However, such a solution does not provide a means for the gNB to receive a report from the UE on various muting pattern in one shot.

[0072] In view of the above, embodiments of the present disclosure include new techniques to ensure that time / frequency resources are used more optimally for various antenna muting pattern configuration transmission by a RAN node and reception by the UE for the purpose of antenna muting / unmuting. Although examples below will be described from the perspective of nodes within an NG- RAN (e.g., a gNB), it should be understood that the examples described below may be applied in substantially the same way to other RAN technologies (e.g., future technologies derived from 3GPP 5G, or legacy technologies such as LTE).

[0073] Various techniques described herein may advantageously be used to prepare for a change to the antenna muting configuration by determining a specific set of ports to either mute or unmute while improving performance in the changed state. Preferred embodiments would do so with a minimal number of resource transmissions from the gNB and receptions by the UE.

[0074] According to many of the embodiments described herein, a network node 20 (e.g., a gNB) serves a cell 80 (or beam) to a UE 30, e.g., as shown in example network 10 of Figure 4. While many of the examples provided herein will specifically make reference to a gNB, it should be understood that this is only an example of a network node that may be used depending on the embodiment. Other network nodes 20 that may be used in substantially similar embodiments may include other kinds of RAN nodes, eNBs, base stations, and other kinds of nodes derived from 3GPP RAN technologies. It should also be understood that the network 10 may include other network nodes and / or UEs, which are not shown in Figure 4 for purposes of clarity.

[0075] One example general approach that enables improved switching of antenna muting states in accordance with at least some of the embodiments disclosed herein includes a gNB that provides, to the UE 30, one or more configurations for measurement and feedback on a plurality of partitions (i.e., antenna port patterns or arrangements). When evaluating switching down from a larger number of active antenna ports to a smaller number of active antenna ports, a configuration may comprise a measurement of all available antenna ports and at least one configuration may comprise a measurement of a subset of the available antenna ports. When evaluating switching up from a smaller number of active antenna ports to a larger number of antenna ports, the gNB may activate additional antenna-related hardware (e.g., power amplifiers) for the purpose of transmitting additional CSI-RS ports, thereby enabling configuring the UE 30 with a measurement comprising a higher number of antenna ports than what the UE 30 is currently using.

[0076] Particular embodiments include a method 300 implemented by a network node 20 (e.g., a gNB serving a cell 80 to a UE 30) as shown in Figure 5. The method 300 comprises providing, to a UE 30, a plurality of CSI-RS resource configurations that overlap on at least one time / frequency resource and use the same CDM type, each CSI-RS resource configuration corresponding to a respective antenna port (block 310). The method 300 further comprises transmitting, to the UE 30, a request to perform CSI-RS measurements on one or more of the antenna ports (block 320). The method 300 further comprises receiving, from the UE 30, one or more measurement reports of the one or more antenna ports, each antenna port measured in accordance with the corresponding CSI-RS resource configuration (block 330). The method 300 further comprises switching one or more antennas of the network node 20 between muted and unmuted based on the one or more reports (step 340).

[0077] The CSI-RS resource configurations may be defined in a variety of ways, depending on the embodiment. For example, in some embodiments, the CSI-RS resource configurations may be described hierarchically, e.g., according to a multi-port CSI-RS resource configuration and an associated configuration that addresses one or more partitions of the multi-port CSI-RS resource configuration. For example, the multi-port CSI-RS resource configuration may be described by a CSI-MeasConfig IE and the associated configuration may be described by a substructure thereof (e.g., CSI-ReportConfig, Triggerstate, etc.).

[0078] Alternatively, the resource configurations may be described non- hierarchically with each CSI-RS resource configuration comprising indicating time / frequency resources used for a CSI-RS, and at least one time / frequency resource is common between the different CSI-RS configurations. In such an embodiment, each CSI-RS resource configuration may be described by an appropriate IE, e.g., CSI-MeasConfig, CSI-ReportConfig, Triggerstate, etc.

[0079] In some embodiments, the measurement request sent to the UE 30 may be comprised in an L2 MAC CE or an L1 DCI. In some embodiments, the request may explicitly specify the one or more antenna ports for which measurements are requested in the L1 or L2 signaling itself. Alternatively, the indication may refer to one or more CSI-RS configurations previously provided to the UE 30 (e.g., in a previous CSI-MeasConfig or a substructure thereof).

[0080] In some embodiments, the one or more antenna ports to measure and report on is signaled using one or more bits. The meaning of each bit may one or more antenna ports or CDM groups of ports. In some embodiments, the meaning of each bit may be configurable.

[0081] In some embodiments, the method 300 further comprises transmitting CSI-RS according to the CSI-RS resource configuration of each antenna port the UE 30 was requested to measure (e.g., including such time / frequency resources that overlap). CDM may be used to separate the reference signals that overlap. Thus, the UE 30 may receive the reference signals transmitted by the gNB and measure according to one or more of the configurations provided. Having performed the measurements, the UE 30 may report the measurements to the gNB.

[0082] Other embodiments include a method 200 implemented by a UE 30, e.g., as shown in Figure 6. The method 200 comprises receiving, from a network node 20, a plurality of CSI-RS resource configurations that overlap on at least one time / frequency resource and use the same CDM type, each CSI-RS resource configuration corresponding to a respective antenna port (block 210). The method 200 further comprises receiving, from the network node 20, a request to perform CSI-RS measurements on one or more of the antenna ports (block 220). The method 200 further comprises measuring each of the one or more antenna ports in accordance with the corresponding CSI-RS resource configuration (block 230). The method 200 further comprises transmitting, to the network node 20, one or more measurement reports comprising one or more results of the measuring (block 240).

[0083] Consistent with one or more aspects of at least some of the embodiments described above, a further method 400, implemented by network node 20, is illustrated in Figure 7. The method 400 comprises configuring a UE 30 with CSI- RS resource configurations that at least partially overlap in time / frequency and share the same CDM type (block 410).

[0084] In at least some such embodiments, the network node 20 configures the UE 30 with a first multi-port CSI-RS resource configuration together with associated configurations (e.g., in the CSI-MeasConfig or a substructure of it such as CSI-ReportConfig, Triggerstate, etc.) that addresses or specifies one or more partitions (antenna port arrangements) of the multi-port CSI-RS configuration for UE measurement and reporting. In one embodiment, the configurations for the partitions may specify port number remapping information such as a codebook or a codebook index to be used for evaluating different precoding options for the given port combination. Optionally, in addition to multiple ports, the UE 30 may be configured with additional hypotheses, e.g., multiple CSI-RS to PDSCH offset values.

[0085] The method 400 further comprises determining a set of antenna / port configurations to be measured by the UE 30 (block 420). In some such embodiments, the gNB decides, based on internal or external input, that the UE 30 could potentially operate with good enough or better quality (e.g., in terms of radio link, data throughput, or alike) with some other antenna arrangement than the current arrangement. For example, for an gNB operating with many antenna ports, it may be possible to serve the UE 30 with adequate user experience (e.g., based on SLA agreements, QoS, etc.) using fewer active gNB antennas. Using fewer gNB antennas for transmission / reception may be very beneficial for the gNB in terms of energy consumption. The gNB may decide this based on, e.g., CSI reports from the UE 30. Or conversely, the gNB may determine in a reduced antenna operation mode, based on similar considerations, that that a larger number of antennas and corresponding ports is appropriate to support sufficiently high data transmission KPIs. Furthermore, the gNB may, in some embodiments, adapt other parameters to achieve energy savings, e.g., to adapt the transmission power.

[0086] The method 400 further comprises transmitting, to the UE 30, an indication of which antenna ports to measure (block 430). For example, the network node 20 may intend to assess or verify that the set of antenna / port configurations, or which of multiple active antenna port options, is preferable and transmit an indication to the UE 30 informing it (either directly or indirectly) which antenna port pattern(s) to measure and report on in the upcoming one or more transmission(s). As noted above, each transmission contains reference signals comprising at least partly overlapping resources. Said indication can be an L2 MAC CE or an L1 DCI where the directly implies that one or more groups of ports (one or more groups of CDM groups) for measurement and reporting are provided in the L1 / L2 indication itself. If instead an indirect indication is used, the L1 / L2 indication points at one or more earlier provided (step 100) first associated configurations (e.g., in the CSI-MeasConfig or a substructure of it such as CSI- ReportConfig, Triggerstate, etc.) which in turn identifies one or more partitions of the multi-port CSI-RS. In case an L1 based mechanism is used a bitfield in an existing DCI, e.g, DCI format 0-1 , 1-1 , 0-2, 2-2, or a group common DCI, or a new UE specific or group common DCI can be used in order to perform the indication. The bitfield can be explicitly or implicitly configured from the higher layers, as well as its location and size. The indication may optionally include additional elements, e.g., measuring on multiple power offset values, e.g., CSI- RS to PDSCH.

[0087] The indication may specify multiple antenna arrangement configurations for the UE 30 to evaluate, where each arrangement can be represented using a bit field or a bit map. In one aspect, the included ports or port combinations in a given antenna arrangement are indicated using one or more bits. The bit position, value, and meaning of each bit may be configurable and may correspond to one or more individual ports, a number of ports, or one or more CDM groups of ports. For example, either through configuration or according to the specifications, a 1 bit (e.g., if MSB of a bitmask is set to 1 ) could mean one CDM group where the CDM group comprises a certain number of ports, e.g., as shown in the example of Figure 8 in which a CDM group comprises 8 ports. In Figure 8, each bit of the bit vector K represents two subcarriers.

[0088] The ports of a CDM group are superimposed on each other and can be CDM separated as shown in Figure 9 using the table in Figure 10. The table of Figure 10 includes Wf and Wt values for the separation. Based on the Wf according to table, in time domain, per next symbol, the sequence is multiplied by what Wt(n) says for that symbol. The first subcarrier is Wf(0). The next subcarrier is Wf(1 ). If Wt(n) says -1 , Wf is inverted in that symbol. Figure 11 illustrates the CSI-RS locations within a slot. In this example, row 18 corresponds to the example shown in Figures 9 and 10.

[0089] In another example, 1 bit could have less granularity and point out multiple CDM groups. For example, in Figure 9, if each bit addressed two CDM groups, then an MSB that is set could mean that the first 16 consecutive ports (3000- 3015) are addressed.

[0090] In some embodiments, the gNB can provide different bit configurations (different granularity) per antenna arrangement configuration. For example, the gNB may request measurement on 4 different antenna arrangements (as illustrated in Figure 12), where for each arrangement the bits have different granularity according to associated configurations.

[0091] With continued reference to Figure 7, the method 400 further comprises transmitting, in one transmission, reference signals using at least one overlapping time / frequency resource (block 440). The method 400 further comprises receiving one or more reports from the UE 30 on the antenna ports indicated to measure (block 450). NZP CSI resources may be configured in a variety of ways depending on the embodiment. In a first example, the UE 30 is configured with a list of NZP CSI-RS sets and each set includes an index (e.g., NZP-CSI-RS-ResourceSetld). Within each set, different NZP CSI-RS resources (indexed with NZP-CSI-RS- Resourceld) are configured with same value for number of ports and possibly same cdm_Type and frequencyDomainAllocation.

[0092] Alternatively, in a second example, the UE 30 is configured with a list of NZP CSI-RS sets and each set include NZP-CSI-RS-ResourceSetld. Within each set, different NZP CSI-RS resources (indexed with NZP-CSI-RS-Resourceld) are configured with different assumptions for number of ports and possibly same cdm_Type and frequencyDomainAllocation.

[0093] Alternatively, in a third example, the existing NZP-RS resource configuration is extended to include configuration on CDM group assumptions. This may be implemented in two different ways. It is possible to give more than one CDM group assumption for one NZP CSI-RS resource and, when UE 30 receives this CSI-RS resource transmission, the UE 30 needs to measure it with one or more CDM group assumptions. Note that a CDM group assumption may be also called a “number of port assumption.” Each of these assumptions may have its own index, or these may be referred from elsewhere by their position in a list (e.g., first CDM group assumption, second CDM group assumption, etc.). In this way, these assumptions may be referred in DL MAC CE or DCI in case there is need for the network to point out a specific CDM group assumption. Further, the assumption may need to be indicated in the CSI report of the UE 30. Or CSI report is ordered based on which CDM group assumption it corresponds to. Another alternative to implement the CDM group assumption is that it becomes one additional parameter or one NZP CSI-RS resource and hence each NZP CSRI-RS resource index uniquely identified the NZP CSI-RS and the CDM group assumption associated to it. In this way, existing reporting and activation mechanisms can be used. A possible disadvantage is that it may be seen as consuming NZP CSI-RS index space when one transmission instant is referred to with one or more NZP CSI-RS indices. For the first example, the UE 30 is configured in the CSI-ReportConfig, a threshold which may be one of but not limited to RSRP, RSRQ, SINR, or MCS(CQI). Based on the threshold, UE reports only based on NZP CSI-RS sets, which exceed the threshold. For these sets, UE reports as configured in CSI- ReportConfig or elsewhere. In an alternative, the UE 30 reports the indexes of the NZP CSI-RS sets (similar to CRI that identifies individual resources) which have exceeded the threshold. These indexes may be ordered such that highest value measured in the metric of the threshold is first. In order to achieve this, another indication may need to be included in the report in case only the index / indication of the NZP CSI-RS set is reported back without a metric describing the RSRP / RSRQ / SINR / CQI of the set. This report may be together with the CRI, which is index of the NZP-CSI-RS resource within the set.

[0094] For the second option, the UE 30 is configured in the CSI-ReportConfig, a threshold which may be one of but not limited to RSRP, RSRQ, SINR, or MCS(CQI). Based on a threshold, the UE 30 reports CRIs for each NZP CSI-RS sets based on a preconfigured threshold. Alternatively, the UE 30 may report only those CRI for which the measurement of the NZP CSI-RS resource exceeded the threshold. In this case, the CRI is reported together with an index of the NZP CSI-RS set.

[0095] For the third option, the UE 30 may report based on all configured assumptions or UE 30 may be asked by MAC CE or DCI to provide input one a specific assumption, one MAC CE has a NZP CSI-RS resource index followed by CDM group assumption. For this, a new MAC CE may be defined. In one example, the MAC CE has serving cell index, BWP index and a NZP CSI-RS resource index followed by CDM group assumption. The MAC CE may be of variable size and include one or more of these pairs NZP CSI-RS resource index followed by CDM group assumption.

[0096] Yet another option is that the UE 30 reports a certain fixed report size where the UE 30 is asked to report e.g., X best CSIs out of Y measured with X configured / indicated by gNB. The method 400 further comprises adapting the number of antenna ports used by the network node to transmit (block 460). For example, the gNB may choose to adapt (i.e., mute or unmute) antenna ports based on the UE report(s). In some embodiments, reports aggregated from multiple UEs may be considered to assess the system impact of the configuration change. The adaptation of the antenna ports may be different for different types of transmissions. For example, in one aspect the gNB may choose to maintain the number of ports for transmission of reference signals (e.g., CSI-RS) and broadcast / multicast and only adapt the number of ports for unicast data transmission (e.g., unicast PDSCH). In another aspect the gNB may adapt the number of ports for all types of transmission and / or reception. In one aspect the gNB may have different number of ports for transmissions (e.g., PDCCH / PDSCH) versus reception (e.g., PUCCH / PUSCH). Optionally, the gNB may choose to adapt other transmit parameters, e.g., transmit power or MCS, and as such multiple hypothesis, e.g., CSI-RS to PDSCH should be considered by the UE for reporting.

[0097] In some embodiments, the method 400 further comprises informing the UE 30 of a TCI state change (block 470). For example, once adapted, the gNB may choose to inform the UE 30 about a TCI state change so that the UE 30 decodes the PDCCH and / or PDSCH according to QCL (e.g., when QCL from a previous active configuration cannot be assumed for PDCCH / PDSCH decoding due to the muting). In one such embodiment, the UE 30 may use an explicit L1 or L2 indication (e.g., in case of semi-persistent resource transmission) to inform the UE 30 that the ports have been reconfigured for certain transmissions. This can be done in various ways. In one such example, the UE 30 is informed that the ports have been reconfigured by extending the Semi-Persistent CSI-RS I CSI-IM Resource Set Activation / Deactivation MAC CE. In another example, the TCI State Indication for UE-specific PDCCH MAC CE may be extended. In yet another example, the TCI States Activation / Deactivation for UE-specific PDSCH MAC CE may be extended.

[0098] In one embodiment, in the PDSCH-Config IE, a second list of TCI states is added in addition to the existing first list tci-StatesToAddModList. In the second list, alternative TCI states are configured for the UE 30. It may be specified that UE 30 applies TCI states of one list only at the time. Here the same TCI-Stateld may be used. In this way, if the UE 30 is asked to consider the second list instead of the first list, the UE 30 may effectively change all TCI state configurations, e.g., in coresetconfig and hence the QCL assumptions used by DCIs or MAC CEs. There may be a guard period, a time after which UE 30 can be assumed to have done the switch. UE 30 may be asked to do the switch e.g. by a MAC CE or DCI.

[0099] In an alternative embodiment, the maxNrotTCI-States value is extended which is used in existing first list tci-StatesToAddModList. Disadvantage of this option is that all existing MAC CEs need to be redefined, or new MAC Ces defined as existing MAC CEs are dimensioned for the maxNrofTCI-States value of 128.

[0100] In one embodiment, which assumes each NZP CSI-RS resource has more than one CDM group assumption, after UE has been indicated which CDM group assumption is applicable, UE applies the CDM group assumption in the TCI state as well.

[0101] Other embodiments include a further method 500, implemented by a UE 30, as illustrated in Figure 13. The method 500 comprises receiving, from a network node 20, a plurality of CSI-RS resource configurations that at least partially overlap in time / frequency and share the same CDM type (block 510). The method 500 further comprises receiving, from the network node 20, an indication of which antenna ports to measure (block 520). Blocks 510 and 520 correspond to blocks 410 and 430 discussed above with respect to the network node, mutatis mutandis.

[0102] The method 500 further comprises receiving, in one transmission, reference signals using at least one overlapping time / frequency resource (block 530). For example, the UE 30 may, for the reference signals, perform measurement on the relevant partition(s) (e.g., CDM group(s)) of the antenna ports or potentially other antenna port candidates according to the configurations provided. The measurement process may comprise hypothesis testing where the codebook and active port subset combinations for the different candidate antenna configurations may be disjoint or may partially overlap. For example, all or part of a hypothesis set of a smaller (e.g. first) port combination may be a subset of a hypothesis set of a larger (e.g. second) port combination. In one embodiment, the UE 30 may store intermediate or final evaluation results during the first port combination evaluation and reuse them during the second evaluation with needing to perform duplicate computations. The UE 30 may apply hypothesis space reduction techniques to avoid explicitly evaluating all codebook entries. In one embodiment, the UE 30 may use evaluation results of one port combination (e.g. the first) as side information for space reduction for another (e.g. the second).

[0103] The method 500 further comprises transmitting one or more reports regarding the antenna ports indicated to measure (block 540). The reporting is performed according to the configuration, e.g., in accordance with one or more of the approaches described above.

[0104] In some embodiments, the method 500 further comprises receiving an indication of a TCI state (e.g., the current state, a state change). In some such embodiments, the indication of the TCI state is regarding the antenna, port, power, and / or MCS configuration of one or more cells.

[0105] For example, the UE 30 may receive TCI state info for a changed active antenna port configuration. The UE 30 then may use CSI-RS reception info from the evaluation process to optimize PDCDCH / PDSCH reception according to QCL assumptions. If no TCI state update info is received, in one embodiment, the UE 30 may continue operating under previous TCI state assumption. In another embodiment, the UE may use the fact that the indication has been received as a trigger to perform proprietary PDCCH / PDSCH reception optimization, considering the possibility the QCL to the previous TCI state no longer holds. The optimization of PDSCH reception may be done e.g. based on PDCCH reception, estimating e.g. preferred spatial combining weights to maximize e.g. SINR.

[0106] It will be appreciated that many of the features of methods 300 and 400, implemented by a network node 20 as discussed above, are compatible. Therefore, one or more of the features of one may be incorporated into the other. Similarly, many of the features of methods 200 and 500, implemented by a UE 30 as discussed above, are compatible such that one or more of the features of one may be incorporated into the other.

[0107] The UE 30 may, for example, be implemented as schematically illustrated in the example of Figure 14. The UE 30 of Figure 14 comprises processing circuitry 610, memory circuitry 620, and interface circuitry 630. The processing circuitry 610 is communicatively coupled to the memory circuitry 620 and the interface circuitry 630, e.g., via a bus 604. The processing circuitry 610 may comprise one or more microprocessors, microcontrollers, hardware circuits, discrete logic circuits, hardware registers, digital signal processors (DSPs), field- programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), or a combination thereof. For example, the processing circuitry 610 may be programmable hardware capable of executing software instructions stored, e.g., as a machine-readable computer program 640 in the memory circuitry 620. The memory circuitry 620 of the various embodiments may comprise any non- transitory machine-readable media known in the art or that may be developed, whether volatile or non-volatile, including but not limited to solid state media (e.g., SRAM, DRAM, DDRAM, ROM, PROM, EPROM, flash memory, solid state drive, etc.), removable storage devices (e.g., Secure Digital (SD) card, miniSD card, microSD card, memory stick, thumb-drive, USB flash drive, ROM cartridge, Universal Media Disc), fixed drive (e.g., magnetic hard disk drive), or the like, wholly or in any combination.

[0108] The interface circuitry 630 may be a controller hub configured to control the input and output (I / O) data paths of the UE 30. Such I / O data paths may include data paths for exchanging signals over a network. The interface circuitry 630 may be implemented as a unitary physical component, or as a plurality of physical components that are contiguously or separately arranged, any of which may be communicatively coupled to any other, or may communicate with any other via the processing circuitry 610. For example, the interface circuitry 630 may comprise a transmitter 632 configured to send wireless communication signals and a receiver 634 configured to receive wireless communication signals.

[0109] The UE 30 may be configured to perform the method 200 and / or the method 400 described above. In one example, the processing circuitry 610 may be configured to receive, from a network node 20, a plurality of CSI-RS resource configurations that overlap on at least one time / frequency resource and use the same CDM type, each CSI-RS resource configuration corresponding to a respective antenna port. The processing circuitry 610 may be further configured to receive, from the network node 20, a request to perform CSI-RS measurements on one or more of the antenna ports. The processing circuitry 610 may be further configured to measure each of the one or more antenna ports in accordance with the corresponding CSI-RS resource configuration. The processing circuitry 610 may be further configured to transmit, to the network node 20, one or more measurement reports comprising one or more results of the measuring.

[0110] Still other embodiments include a control program 640 comprising instructions that, when executed on processing circuitry 610 of a UE 30, cause the UE 30 to carry out the method 200 and / or the method 400 described above.

[0111] Yet other embodiments include a carrier containing the control program 640. The carrier is one of an electronic signal, optical signal, radio signal, or computer readable storage medium.

[0112] Similarly, a network node 20 (e.g., a gNB) may be implemented as schematically illustrated in the example of Figure 15. The network node 20 of Figure 15 comprises processing circuitry 710, memory circuitry 720, and interface circuitry 730. The processing circuitry 710 is communicatively coupled to the memory circuitry 720 and the interface circuitry 730, e.g., via a bus 704. The processing circuitry 710 may comprise one or more microprocessors, microcontrollers, hardware circuits, discrete logic circuits, hardware registers, digital signal processors (DSPs), field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), or a combination thereof. For example, the processing circuitry 710 may be programmable hardware capable of executing software instructions stored, e.g., as a machine-readable computer program 740 in the memory circuitry 720. The memory circuitry 720 of the various embodiments may comprise any non-transitory machine-readable media known in the art or that may be developed, whether volatile or non-volatile, including but not limited to solid state media (e.g., SRAM, DRAM, DDRAM, ROM, PROM, EPROM, flash memory, solid state drive, etc.), removable storage devices (e.g., Secure Digital (SD) card, miniSD card, microSD card, memory stick, thumb-drive, USB flash drive, ROM cartridge, Universal Media Disc), fixed drive (e.g., magnetic hard disk drive), or the like, wholly or in any combination.

[0113] The interface circuitry 730 may be a controller hub configured to control the input and output (I / O) data paths of the network node 20. Such I / O data paths may include data paths for exchanging signals over a network. The interface circuitry 730 may be implemented as a unitary physical component, or as a plurality of physical components that are contiguously or separately arranged, any of which may be communicatively coupled to any other, or may communicate with any other via the processing circuitry 710. For example, the interface circuitry 730 may comprise a transmitter 732 configured to send wireless communication signals and a receiver 734 configured to receive wireless communication signals.

[0114] The network node 20 may be configured to perform the method 300 and / or the method 400 described above. In one example, the processing circuitry 710 may be configured to provide, to a UE 30, a plurality of CSI-RS resource configurations that overlap on at least one time / frequency resource and use the same CDM type, each CSI-RS resource configuration corresponding to a respective antenna port. The processing circuitry 710 may be further configured to transmit, to the UE 30, a request to perform CSI-RS measurements on one or more of the antenna ports. The processing circuitry 710 may be further configured to receive, from the UE 30, one or more measurement reports of the one or more antenna ports, each antenna port measured in accordance with the corresponding CSI-RS resource configuration. The processing circuitry 710 may be further configured to switch one or more antennas of the network node 20 between muted and unmuted based on the one or more reports.

[0115] Still other embodiments include a control program 740 comprising instructions that, when executed on processing circuitry 710 of a network node 20, cause the network node 20 to carry out the method 300 and / or method 400 described above.

[0116] Yet other embodiments include a carrier containing the control program 740. The carrier is one of an electronic signal, optical signal, radio signal, or computer readable storage medium.

[0117] Although the computing devices described herein (e.g., UEs 30, network nodes 20) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and / or software needed to perform the tasks, features, functions, and methods disclosed herein. Determining, calculating, obtaining or similar operations described herein may be performed by processing circuitry that processes information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and / or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, the devices described herein may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components.

[0118] Additional embodiments will now be described. At least some of these embodiments may be described as applicable in certain contexts and / or wireless network types for illustrative purposes, but the embodiments are similarly applicable in other contexts and / or wireless network types not explicitly described. Figure 16 shows an example of a communication system 1100 in accordance with some embodiments.

[0119] In the example, the communication system 1100 includes a telecommunication network 1102 that includes an access network 1104, such as a radio access network (RAN), and a core network 1106, which includes one or more core network nodes 1108. The access network 1104 includes one or more access network nodes, such as network nodes 1110a and 1110b (one or more of which may be generally referred to as network nodes 1110), or any other similar 3rd Generation Partnership Project (3GPP) access node or non-3GPP access point. The network nodes 1110 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 1112a, 1112b, 1112c, and 1112d (one or more of which may be generally referred to as UEs 1112) to the core network 1106 over one or more wireless connections.

[0120] Example wireless communications over a wireless connection include transmitting and / or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and / or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 1100 may include any number of wired or wireless networks, network nodes, UEs, and / or any other components or systems that may facilitate or participate in the communication of data and / or signals whether via wired or wireless connections. The communication system 1100 may include and / or interface with any type of communication, telecommunication, data, cellular, radio network, and / or other similar type of system.

[0121] The UEs 1112 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and / or operable to communicate wirelessly with the network nodes 1110 and other communication devices. Similarly, the network nodes 1110 are arranged, capable, configured, and / or operable to communicate directly or indirectly with the UEs 1112 and / or with other network nodes or equipment in the telecommunication network 1102 to enable and / or provide network access, such as wireless network access, and / or to perform other functions, such as administration in the telecommunication network 1102.

[0122] In the depicted example, the core network 1106 connects the network nodes 1110 to one or more hosts, such as host 1116. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 1106 includes one more core network nodes (e.g., core network node 1108) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and / or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 1108. Example core network nodes include functions of one or more of an MSC, MME, HSS, AMF, SMF, AUSF, SIDF, UDM, SEPP, NEF, and / or UPF.

[0123] The host 1116 may be under the ownership or control of a service provider other than an operator or provider of the access network 1104 and / or the telecommunication network 1102, and may be operated by the service provider or on behalf of the service provider. The host 1116 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio / video content, data collection services such as retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server.

[0124] As a whole, the communication system 1100 of Figure 16 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and / or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and / or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and / or any low-power wide-area network (LPWAN) standards such as LoRa and Sigfox.

[0125] In some examples, the telecommunication network 1102 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 1102 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 1102. For example, the telecommunications network 1102 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing Enhanced Mobile Broadband (eMBB) services to other UEs, and / or mMTC / Massive loT services to yet further UEs.

[0126] In some examples, the UEs 1112 are configured to transmit and / or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 1104 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 1104. Additionally, a UE may be configured for operating in single- or multi-RAT or multi-standard mode. For example, a UE may operate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e. being configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN-DC).

[0127] In the example, the hub 1114 communicates with the access network 1104 to facilitate indirect communication between one or more UEs (e.g., UE 1112c and / or 1112d) and network nodes (e.g., network node 1110b). In some examples, the hub 1114 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 1114 may be a broadband router enabling access to the core network 1106 for the UEs. As another example, the hub 1114 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 1110, or by executable code, script, process, or other instructions in the hub 1114. As another example, the hub 1114 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 1114 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 1114 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 1114 then provides to the UE either directly, after performing local processing, and / or after adding additional local content. In still another example, the hub 1114 acts as a proxy server or orchestrator for the UEs, in particular in if one or more of the UEs are low energy loT devices.

[0128] The hub 1114 may have a constant / persistent or intermittent connection to the network node 1110b. The hub 1114 may also allow for a different communication scheme and / or schedule between the hub 1114 and UEs (e.g., UE 1112c and / or 1112d), and between the hub 1114 and the core network 1106. In other examples, the hub 1114 is connected to the core network 1106 and / or one or more UEs via a wired connection. Moreover, the hub 1114 may be configured to connect to an M2M service provider over the access network 1104 and / or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 1110 while still connected via the hub 1114 via a wired or wireless connection. In some embodiments, the hub 1114 may be a dedicated hub - that is, a hub whose primary function is to route communications to / from the UEs from / to the network node 1110b. In other embodiments, the hub 1114 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 1110b, but which is additionally capable of operating as a communication start and / or end point for certain data channels.

[0129] Figure 17 is a block diagram of a host 1400, which may be an embodiment of the host 1116 of Figure 16, in accordance with various aspects described herein. As used herein, the host 1400 may be or comprise various combinations hardware and / or software, including a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, container, or processing resources in a server farm. The host 1400 may provide one or more services to one or more UEs.

[0130] The host 1400 includes processing circuitry 1402 that is operatively coupled via a bus 1404 to an input / output interface 1406, a network interface 1408, a power source 1410, and a memory 1412. Other components may be included in other embodiments. Features of these components may be substantially similar to those described with respect to the devices of previous figures, such that the descriptions thereof are generally applicable to the corresponding components of host 1400.

[0131] The memory 1412 may include one or more computer programs including one or more host application programs 1414 and data 1416, which may include user data, e.g., data generated by a UE for the host 1400 or data generated by the host 1400 for a UE. Embodiments of the host 1400 may utilize only a subset or all of the components shown. The host application programs 1414 may be implemented in a container-based architecture and may provide support for video codecs (e.g., Versatile Video Coding (WO), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), MPEG, VP9) and audio codecs (e.g., FLAC, Advanced Audio Coding (AAC), MPEG, G.711 ), including transcoding for multiple different classes, types, or implementations of UEs (e.g., handsets, desktop computers, wearable display systems, heads-up display systems). The host application programs 1414 may also provide for user authentication and licensing checks and may periodically report health, routes, and content availability to a central node, such as a device in or on the edge of a core network. Accordingly, the host 1400 may select and / or indicate a different host for over-the-top services for a UE. The host application programs 1414 may support various protocols, such as the HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (MPEG-DASH), etc. Figure 18 shows a communication diagram of a host 1602 communicating via a network node 1604 with a UE 1606 over a partially wireless connection in accordance with some embodiments. Example implementations, in accordance with various embodiments, of the UE (such as a UE 1112a of Figure 16), network node (such as network node 1110a of Figure 16), and host (such as host 1116 of Figure 16) discussed in the preceding paragraphs will now be described with reference to Figure 18.

[0132] Like host 1400, embodiments of host 1602 include hardware, such as a communication interface, processing circuitry, and memory. The host 1602 also includes software, which is stored in or accessible by the host 1602 and executable by the processing circuitry. The software includes a host application that may be operable to provide a service to a remote user, such as the UE 1606 connecting via an over-the-top (OTT) connection 1650 extending between the UE 1606 and host 1602. In providing the service to the remote user, a host application may provide user data which is transmitted using the OTT connection 1650.

[0133] The network node 1604 includes hardware enabling it to communicate with the host 1602 and UE 1606. The connection 1660 may be direct or pass through a core network (like core network 1106 of Figure 16) and / or one or more other intermediate networks, such as one or more public, private, or hosted networks. For example, an intermediate network may be a backbone network or the Internet.

[0134] The UE 1606 includes hardware and software, which is stored in or accessible by UE 1606 and executable by the UE’s processing circuitry. The software includes a client application, such as a web browser or operator-specific “app” that may be operable to provide a service to a human or non-human user via UE 1606 with the support of the host 1602. In the host 1602, an executing host application may communicate with the executing client application via the OTT connection 1650 terminating at the UE 1606 and host 1602. In providing the service to the user, the UE's client application may receive request data from the host's host application and provide user data in response to the request data. The OTT connection 1650 may transfer both the request data and the user data. The UE's client application may interact with the user to generate the user data that it provides to the host application through the OTT connection 1650.

[0135] The OTT connection 1650 may extend via a connection 1660 between the host 1602 and the network node 1604 and via a wireless connection 1670 between the network node 1604 and the UE 1606 to provide the connection between the host 1602 and the UE 1606. The connection 1660 and wireless connection 1670, over which the OTT connection 1650 may be provided, have been drawn abstractly to illustrate the communication between the host 1602 and the UE 1606 via the network node 1604, without explicit reference to any intermediary devices and the precise routing of messages via these devices.

[0136] As an example of transmitting data via the OTT connection 1650, in step 1608, the host 1602 provides user data, which may be performed by executing a host application. In some embodiments, the user data is associated with a particular human user interacting with the UE 1606. In other embodiments, the user data is associated with a UE 1606 that shares data with the host 1602 without explicit human interaction. In step 1610, the host 1602 initiates a transmission carrying the user data towards the UE 1606. The host 1602 may initiate the transmission responsive to a request transmitted by the UE 1606. The request may be caused by human interaction with the UE 1606 or by operation of the client application executing on the UE 1606. The transmission may pass via the network node 1604, in accordance with the teachings of the embodiments described throughout this disclosure. Accordingly, in step 1612, the network node 1604 transmits to the UE 1606 the user data that was carried in the transmission that the host 1602 initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 1614, the UE 1606 receives the user data carried in the transmission, which may be performed by a client application executed on the UE 1606 associated with the host application executed by the host 1602.

[0137] In some examples, the UE 1606 executes a client application which provides user data to the host 1602. The user data may be provided in reaction or response to the data received from the host 1602. Accordingly, in step 1616, the UE 1606 may provide user data, which may be performed by executing the client application. In providing the user data, the client application may further consider user input received from the user via an input / output interface of the UE 1606. Regardless of the specific manner in which the user data was provided, the UE 1606 initiates, in step 1618, transmission of the user data towards the host 1602 via the network node 1604. In step 1620, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 1604 receives user data from the UE 1606 and initiates transmission of the received user data towards the host 1602. In step 1622, the host 1602 receives the user data carried in the transmission initiated by the UE 1606.

[0138] One or more of the various embodiments improve the performance of OTT services provided to the UE 1606 using the OTT connection 1650, in which the wireless connection 1670 forms the last segment. More precisely, the teachings of these embodiments may enable OTT services to be delivered reliably without over consumption of power and with adequate quality of service. In an example scenario, factory status information may be collected and analyzed by the host 1602. As another example, the host 1602 may process audio and video data which may have been retrieved from a UE for use in creating maps. As another example, the host 1602 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controlling traffic lights). As another example, the host 1602 may store surveillance video uploaded by a UE. As another example, the host 1602 may store or control access to media content such as video, audio, VR or AR which it can broadcast, multicast or unicast to UEs. As other examples, the host 1602 may be used for energy pricing, remote control of non-time critical electrical load to balance power generation needs, location services, presentation services (such as compiling diagrams etc. from data collected from remote devices), or any other function of collecting, retrieving, storing, analyzing and / or transmitting data.

[0139] In some examples, a measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 1650 between the host 1602 and UE 1606, in response to variations in the measurement results. The measurement procedure and / or the network functionality for reconfiguring the OTT connection may be implemented in software and hardware of the host 1602 and / or UE 1606. In some embodiments, sensors (not shown) may be deployed in or in association with other devices through which the OTT connection 1650 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 1650 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not directly alter the operation of the network node 1604. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling that facilitates measurements of throughput, propagation times, latency and the like, by the host 1602. The measurements may be implemented in that software causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 1650 while monitoring propagation times, errors, etc.

[0140] Abbreviations

[0141] 3GPP Third Generation Partnership Project

[0142] 2G Second Generation

[0143] 3G Third Generation

[0144] 4G Fourth Generation

[0145] 5G Fifth Generation

[0146] 6G Sixth Generation

[0147] AMF Access and Mobility management Function

[0148] AR Augmented Reality

[0149] AUSF Authentication Server Function

[0150] BWP Bandwidth Part CDM Code Division Multiplexing

[0151] CQI Channel Quality Indicator

[0152] CRI CSI-RS Resource Indicator

[0153] CSI Channel State Information

[0154] CSI-IM Channel State Information Interference Measurement

[0155] CSI-RS Channel State Information Reference Signal

[0156] DC Dual Connectivity

[0157] DCI Downlink Control Information

[0158] DL Downlink eNB (ELITRAN) base station

[0159] E-UTRAN Evolved Universal Terrestrial Radio Access Network gNB gNodeB

[0160] HSS Home Subscriber Server

[0161] IE Information Element loT Internet of Things

[0162] KPI Key Performance Indicator

[0163] L1 Layer 1

[0164] L2 Layer 2

[0165] LTE Long Term Evolution

[0166] M2M Machine-to-Machine

[0167] MAC Medium Access Control

[0168] MAC CE MAC Control Element

[0169] MCS Modulation and Coding Scheme

[0170] MME Mobility Management Entity mMTC Massive Machine Type Communication

[0171] MN Master Node

[0172] MR-DC Multi-Radio Dual Connectivity

[0173] MSB Most Significant Bit

[0174] MSC Mobile Switching Center

[0175] MTC Machine Type Communication

[0176] NEF Network Exposure Function NG-RAN Next Generation Radio Access Network

[0177] NR New Radio

[0178] NW Network

[0179] NZP Non-Zero Power

[0180] OCC Orthogonal Cover Code

[0181] PDCCH Physical Downlink Control Channel

[0182] PDSCH Physical Downlink Shared Channel

[0183] PLICCH Physical Uplink Control Channel

[0184] PUSCH Physical Uplink Shared Channel

[0185] QCL Quasi Co-Location

[0186] QoS Quality of Service

[0187] RAN Radio Access Network

[0188] RAT Radio Access Technology

[0189] RF Radio Frequency

[0190] RRC Radio Resource Control

[0191] RSRP Reference Signal Received Power

[0192] RSRQ Reference Signal Received Quality

[0193] RX Receive

[0194] SEPP Security Edge Protection Proxy

[0195] SIDF Subscriber Identifier De-concealing Function

[0196] SINR Signal to Interference plus Noise Ratio

[0197] SLA Service Level Agreement

[0198] SMF Session Management Function

[0199] TCI Transmission Configuration Indication

[0200] TX Transmit

[0201] UDM Unified Data Management

[0202] UE User Equipment

[0203] UPF User Plane Function

[0204] URLLC Ultra Reliable Low Latency Communication

[0205] USB Universal Serial Bus

[0206] VR Virtual Reality

Claims

CLAIMSWhat is claimed is:

1. A method (200), implemented by a User Equipment, UE (30), the method comprising: receiving (210), from a network node (20), a plurality of Channel State Information Reference Signal, CSI-RS, resource configurations that overlap on at least one time / frequency resource and use the same Code Division Multiplexing, CDM, type, each CSI-RS resource configuration corresponding to a respective antenna port; receiving (220), from the network node (20), a request to perform CSI-RS measurements on one or more of the antenna ports; measuring (230) each of the one or more antenna ports in accordance with the corresponding CSI-RS resource configuration; and transmitting (240), to the network node (20), one or more measurement reports comprising one or more results of the measuring.

2. The method of claim 1 , wherein receiving the plurality of CSI-RS resource configurations comprises receiving an Information Element, IE, describing a first CSI-RS resource configuration.

3. The method of any one of the preceding claims, wherein receiving the plurality of CSI-RS resource configurations comprises receiving an IE describing a second CSI-RS resource configuration.

4. The method of any one of the preceding claims, wherein receiving the plurality of CSI-RS resource configurations comprises receiving a multi-port CSI- RS configuration comprising the plurality of CSI-RS resource configurations.

5. The method of claim 4, wherein the multi-port CSI-RS configuration further comprises port number remapping information.

6. The method of claim 5, wherein the port number remapping information comprises a codebook or codebook index.

7. The method of any one of claims 4-6, wherein the multi-port CSI-RS configuration further comprises one or more CSI-RS to Physical Downlink Shared Channel, PDSCH, offset values.

8. The method of any one of the previous claims, wherein the request to perform the CSI-RS measurements is comprised in Layer 2 signaling.

9. The method of claim 8, wherein the request to perform the CSI-RS measurements is comprised in a Medium Access Control, MAC, Control Element, CE of the Layer 2 signaling.

10. The method of any one of claims 1-7, wherein the request to perform the CSI-RS measurements is comprised in Layer 1 signaling.

11. The method of claim 10, wherein the request to perform the CSI-RS measurements is comprised in Downlink Control Information, DCI, of the Layer 1 signaling.

12. The method of any one of the previous claims, wherein the request to perform the CSI-RS measurements comprises a CDM group to measure.

13. The method of any one of claims 1-11 , wherein the request to perform the CSI-RS measurements comprises reference to one or more of the CSI-RS resource configurations.

14. The method of any one of the previous claims, wherein the request to perform the CSI-RS measurements comprises a bitfield indicating the one or more of the antenna ports to measure.

15. The method of any one of the previous claims, further comprising receiving, from the network node (20), a Transmission Configuration Indicator, TCI, state change in response to transmitting the one or more measurement reports.

16. A User Equipment, UE (30), comprising: interface circuitry (630) and processing circuitry (610) communicatively connected to the interface circuitry (630), wherein the processing circuitry (610) is configured to: receive, from a network node (20) and via the interface circuitry (630), a plurality of Channel State Information Reference Signal, CSI-RS, resource configurations that overlap on at least one time / frequency resource and use the same Code Division Multiplexing, CDM, type, each CSI-RS resource configuration corresponding to a respective antenna port; receive, from the network node (20) and via the interface circuitry (630), a request to perform CSI-RS measurements on one or more of the antenna ports; measure each of the one or more antenna ports in accordance with the corresponding CSI-RS resource configuration; and transmit, to the network node (20) via the interface circuitry (630), one or more measurement reports comprising one or more results of the measuring.

17. The UE of the previous claim, wherein the processing circuitry (610) is further configured to perform the method according to any one of claims 2-15.

18. A computer program (640) comprising instructions that, when executed on processing circuitry of a User Equipment, UE (30), cause the UE (30) to carry out the method according to any one of claims 1-18.

19. A carrier containing the computer program (640) of the preceding claim, wherein the carrier is one of an electronic signal, optical signal, radio signal, or computer readable storage medium.

20. A method (300), implemented by a network node (20), the method comprising: providing (310), to a User Equipment, UE (30), a plurality of Channel State Indicator Reference Signal, CSI-RS, resource configurations that overlap on at least one time / frequency resource and use the same Code Division Multiplexing, CDM, type, each CSI-RS resource configuration corresponding to a respective antenna port; transmitting (320), to the UE (30), a request to perform CSI-RS measurements on one or more of the antenna ports; receiving (330), from the UE (30), one or more measurement reports of the one or more antenna ports, each antenna port measured in accordance with the corresponding CSI-RS resource configuration; and switching (340) one or more antennas of the network node (20) between muted and unmuted based on the one or more reports.

21. The method of claim 20, wherein providing the plurality of CSI-RS resource configurations comprises transmitting an Information Element, IE, describing a first CSI-RS resource configuration.

22. The method of any one of claims 20-21 , wherein providing the plurality of CSI-RS resource configurations comprises transmitting an IE describing a second CSI-RS resource configuration.

23. The method of any one of claims 20-22, wherein providing the plurality of CSI-RS resource configurations comprises transmitting a multi-port CSI-RS configuration comprising the plurality of CSI-RS resource configurations.

24. The method of claim 23, wherein the multi-port CSI-RS configuration further comprises port number remapping information.

25. The method of claim 24, wherein the port number remapping information comprises a codebook or codebook index.

26. The method of any one of claims 23-25, wherein the multi-port CSI-RS configuration further comprises one or more CSI-RS to Physical Downlink Shared Channel, PDSCH, offset values.

27. The method of any one of claims 20-26, further comprising adapting transmission power based on the one or more reports.

28. The method of any one of claims 20-27, wherein switching the one or more antennas between muted and unmuted is further based on a service quality requirement.

29. The method of claim 28, wherein the service quality requirement is comprised in a Service Level Agreement, SLA.

30. The method of claim 28, wherein the service quality requirement is comprised in a Quality of Service, QoS, agreement.31 . The method of any one of claims 20-30, wherein the request to perform the CSI-RS measurements is comprised in Layer 2 signaling.

32. The method of claim 31 , wherein the request to perform the CSI-RS measurements is comprised in a Medium Access Control, MAC, Control Element, CE of the Layer 2 signaling.

33. The method of any one of claims 20-32, wherein the request to perform the CSI-RS measurements is comprised in Layer 1 signaling.

34. The method of claim 33, wherein the request to perform the CSI-RS measurements is comprised in Downlink Control Information, DCI, of the Layer 1 signaling.

35. The method of any one of claims 20-34, wherein the request to perform the CSI-RS measurements comprises a CDM group to measure.

36. The method of any one of claims 20-34, wherein the request to perform the CSI-RS measurements comprises reference to one or more of the CSI-RS resource configurations.

37. The method of any one of claims 20-36, wherein the request to perform the CSI-RS measurements comprises a bitfield indicating the one or more of the antenna ports to measure.

38. The method of any one of claims 20-37, wherein switching the one or more antennas of the network node (20) between muted and unmuted is further based on at least one further report from another UE.

39. The method of any one of claims 20-38, wherein switching the one or more antennas of the network node (20) between muted and unmuted is further based on a type of transmission to be performed.

40. The method of any one of claims 20-39, wherein switching the one or more antennas of the network node (20) between muted and unmuted comprises switching at least one antenna port between muted and unmuted.

41. The method of any one of claims 20-40, further comprising informing the UE (30) of a Transmission Configuration Indicator, TCI, state change in response to switching the one or more antennas between muted and unmuted.

42. A network node (20) comprising: interface circuitry (730) and processing circuitry (710) communicatively connected to the interface circuitry (730), wherein the processing circuitry (710) is configured to: provide, to a User Equipment, UE (30) via the interface circuitry (730), a plurality of Channel State Indicator Reference Signal, CSI-RS, resource configurations that overlap on at least one time / frequency resource and use the same Code Division Multiplexing, CDM, type, each CSI-RS resource configuration corresponding to a respective antenna port; transmit, to the UE (30) via the interface circuitry (730), a request to perform CSI-RS measurements on one or more of the antenna ports; receive, from the UE (30) via the interface circuitry (730), one or more measurement reports of the one or more antenna ports, each antenna port measured in accordance with the corresponding CSI-RS resource configuration; and switch one or more antennas of the network node (20) between muted and unmuted based on the one or more reports.

43. The network node of the previous claim, wherein the processing circuitry (710) is further configured to perform the method according to any one of claims 21-41.

44. A computer program (740) comprising instructions that, when executed on processing circuitry (710) of a network node (20), cause the network node (20) to carry out the method according to any one of claims 20-41 .

45. A carrier containing the computer program (740) of the preceding embodiment, wherein the carrier is one of an electronic signal, optical signal, radio signal, or computer readable storage medium.

Images