WO2023165708A1

WO2023165708A1 - Control of reception beam sweeping for beam connection maintenance

Info

Publication number: WO2023165708A1
Application number: PCT/EP2022/055575
Authority: WO
Inventors: Sina MALEKI; Santhan THANGARASA; Muhammad Kazmi; Andres Reial; Kazuyoshi Uesaka; Ali Nader
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2022-03-04
Filing date: 2022-03-04
Publication date: 2023-09-07

Abstract

A method of controlling reception beam sweeping by a communication device for beam connection maintenance is disclosed. The method comprises repeatedly evaluating values of one or more parameter obtained at the communication device, wherein the one or more parameter is associated with channel conditions for the communication device. The method also comprises determining whether, for at least one of the one or more parameters, a magnitude of a difference between values of two or more different time instants exceeds a parameter threshold. In response to determining that the magnitude of the difference between values exceeds the parameter threshold, the method comprises applying an adapted reception beam sweeping configuration for the communication device, wherein the adapted reception beam sweeping configuration is obtained by varying an amount of reception beam measurements performed per duration of time. In some embodiments, the one or more parameter comprises a timing advance controlled by timing advance commands of a radio access node. In some embodiments, the one or more parameter comprises a received signal power. Corresponding computer program product, apparatus, user equipment, and radio access node are also disclosed.

Description

CONTROL OF RECEPTION BEAM SWEEPING FOR

BEAM CONNECTION MAINTENANCE

TECHNICAL FIELD

The present disclosure relates generally to the field of wireless communication. More particularly, it relates to reception beam sweeping control for beam connection maintenance.

BACKGROUND

In wireless communication scenarios where beamforming is applied, beam sweeping may be used to maintain beam connection. Beam sweeping generally refers to covering a spatial area with a set of beams transmitted or received at different time intervals and directions. One context where beam sweeping it typically performed relates to making beam decisions. Generally, a beam decision may, for example, comprise selection of a transmission beam and/or a reception beam for communication (e.g., selection of a transmission beam and/or a reception beam that is determined, based on the beam sweeping, to be robust enough for communication).

Reception beam sweeping typically comprises performing a plurality of reception beam measurements; wherein a reception beam sweep typically comprises performing at least one reception beam measurement per transmission-reception beam pair under consideration.

One problem is that each reception beam measurement causes power consumption at the receiver. This may be particularly problematic when the number of reception beam measurements that are to be performed is relatively high and/or when the available power of the receiver is relatively low. One problem is that the reception beam measurements causes a delay until a beam decision is made for connection maintenance. This may be particularly problematic when the number of reception beam measurements that are to be performed is relatively high and/or when the channel changes quickly (e.g., due to device mobility).

US11018746B2 describes a receiver beam tuning approach wherein a base station device can transmit a reference signal that instructs the user equipment to not perform receive beam sweeping, or to perform receive beam sweeping.

One problem with this approach is that it may fail to properly regulate the power consumption at the user equipment, while reliably maintaining beam connection. Alternatively or additionally, this approach may entail a beam decision delay (i.e., the time it takes until a beam decision is made; including the time needed to perform beam sweeping and evaluate options for beam selection) that is long enough to compromise the reliability of beam connection maintenance. Therefore, there is a need for alternative approaches to reception beam sweeping control for beam connection maintenance.

SUMMARY

It should be emphasized that the term “comprises/comprising” (replaceable by “includes/including”) when used in this specification is taken to specify the presence of stated features, integers, steps, or components, but does not preclude the presence or addition of one or more other features, integers, steps, components, or groups thereof. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

Generally, when an arrangement is referred to herein, it is to be understood as a physical product; e.g., an apparatus. The physical product may comprise one or more parts, such as controlling circuitry in the form of one or more controllers, one or more processors, or the like.

It is an object of some embodiments to solve or mitigate, alleviate, or eliminate at least some of the above or other disadvantages.

A first aspect is a method of controlling reception beam sweeping by a communication device for beam connection maintenance. The method comprises repeatedly evaluating values of one or more parameter obtained at the communication device, wherein the one or more parameter is associated with channel conditions for the communication device. The method also comprises determining whether, for at least one of the one or more parameters, a magnitude of a difference between values of two or more different time instants exceeds a parameter threshold. Furthermore, the method comprises, in response to determining that the magnitude of the difference between values exceeds the parameter threshold, applying an adapted reception beam sweeping configuration for the communication device, wherein the adapted reception beam sweeping configuration is obtained by varying an amount of reception beam measurements performed per duration of time.

In some embodiments, the amount of reception beam measurements performed per duration of time for the adapted reception beam sweeping configuration is lower than a default amount of reception beam measurements performed per duration of time for a default reception beam sweeping configuration.

In some embodiments, varying the amount of reception beam measurements performed per duration of time comprises one or more of: increasing or decreasing a total number of reception beam measurements performed during a reception beam sweep, increasing or decreasing a number of reception beams considered per transmission beam, increasing or decreasing a number of transmission beams considered per reception beam, increasing or decreasing a reception beam sweeping rate, and increasing or decreasing (for at least one reception beam) a number of reception beam measurements performed for the reception beam.

In some embodiments, the adapted reception beam sweeping configuration is a first adapted reception beam sweeping configuration, and the method further comprises applying a second adapted reception beam sweeping configuration in response to determining that the magnitude of the difference between values does not exceed the parameter threshold.

In some embodiments, the amount of reception beam measurements performed per duration of time for the first and/or second adapted reception beam sweeping configuration is lower than a default amount of reception beam measurements performed per duration of time for a default reception beam sweeping configuration.

In some embodiments, the amount of reception beam measurements performed per duration of time for the first adapted reception beam sweeping configuration is higher than the amount of reception beam measurements performed per duration of time for the second adapted reception beam sweeping configuration.

In some embodiments, the one or more parameter comprises a timing advance controlled by timing advance commands of a radio access node.

In some embodiments, determining that the magnitude of the difference between values exceeds the parameter threshold for the timing advance comprises determining that a magnitude of a difference between a first timing advance value resulting from a first timing advance command of a first time instance and a second timing advance value resulting from a second timing advance command of a second time instance exceeds a timing advance threshold.

In some embodiments, the amount of reception beam measurements performed per duration of time is decreased when the magnitude of the difference between the first timing advance value and the second timing advance value is less than the timing advance threshold, and/or the amount of reception beam measurements performed per duration of time is increased when the magnitude of the difference between the first timing advance value and the second timing advance value exceeds the timing advance threshold.

In some embodiments, applying the adapted reception beam sweeping configuration is performed only when a time alignment timer of the communication device is running.

In some embodiments, the one or more parameter comprises a received signal power.

In some embodiments, determining that the magnitude of the difference between values exceeds the parameter threshold for the received signal power comprises determining that a magnitude of a difference between a first signal power received at a first time instance and a second signal power received at a second, later, time instance exceeds a received signal power threshold. In some embodiments, the method further comprises determining whether the second signal power is higher than the first signal power.

In some embodiments, applying the adapted reception beam sweeping configuration comprises decreasing the amount of reception beam measurements performed per duration of time when the second signal power is higher than the first signal power, and/or increasing the amount of reception beam measurements performed per duration of time when the first signal power is higher than the second signal power.

In some embodiments, the method is selectively performed depending on a physical downlink control channel, PDCCH, monitoring state of the communication device.

In some embodiments, the method is selectively performed, for one or more cell with intrafrequency reception beam measurements, depending on received signal power value.

In some embodiments, the method is selectively performed, for one or more neighbor cell with inter-frequency reception beam measurements, depending on received signal power value.

In some embodiments, the method is selectively performed depending on a mobility status of the communication device.

In some embodiments, the method is selectively performed depending on a user equipment, UE, power class used for operation by the communication device.

A second aspect is a computer program product comprising a non-transitory computer readable medium, having thereon a computer program comprising program instructions. The computer program is loadable into a data processing unit and configured to cause execution of the method according to the first aspect when the computer program is run by the data processing unit.

A third aspect is an apparatus for controlling reception beam sweeping by a communication device for beam connection maintenance. The apparatus comprises controlling circuitry configured to cause repeated evaluation of values of one or more parameter obtained at the communication device, wherein the one or more parameter is associated with channel conditions for the communication device. The controlling circuitry is also configured to cause determination of whether, for at least one of the one or more parameters, a magnitude of a difference between values of two or more different time instants exceeds a parameter threshold. Furthermore, the controlling circuitry is also configured to cause (in response to determination that the magnitude of the difference between values exceeds the parameter threshold) application of an adapted reception beam sweeping configuration for the communication device, wherein the adapted reception beam sweeping configuration is obtained by varying an amount of reception beam measurements performed per duration of time.

A fourth aspect is a user equipment (UE) comprising the apparatus of the third aspect.

A fifth aspect is a radio access node comprising the apparatus of the third aspect. In some embodiments, any of the above aspects may additionally have features identical with or corresponding to any of the various features as explained above for any of the other aspects.

An advantage of some embodiments is that alternative approaches are provided for reception beam sweeping control. Some embodiments provide beam sweeping control that is particularly suitable for beam connection maintenance.

An advantage of some embodiments is that improved approaches are provided for reception beam sweeping control. For example, improvement in relation to other approaches may be achieved in terms of one or more of: reduced power consumption, reduced delay until a beam decision for connection maintenance is made, and increased reliability of beam connection maintenance.

An advantage of some embodiments is that reception beam sweeping is dynamically adjustable. For example, the reception beam sweeping may be dynamically adjusted based on one or more of: channel conditions, mobility status, and power consumption conditions. Thereby, trade-off which is adequate for the situation at hand may be achieved between reliability of beam connection maintenance and power consumption and/or beam decision delay. For example, the amount of reception beam measurements may be reduced as much as possible without severely compromising reliability of beam connection maintenance.

An advantage of some embodiments is that use of the adapted reception beam sweeping configuration(s) is controlled autonomously by the receiver device (e.g., a user equipment, UE). Thereby, conditions perceivable only at the receiver (e.g., power status and/or channel conditions) can be taken into account without reporting to the transmitter, and no specific control protocol (e.g., a differentiated reference signal format) is required for enabling the transmitter to control the reception beam sweeping configuration.

An advantage of some embodiments is that the power consumption of the receiver may be reduced compared to other approaches. For example, a reduction of the amount of reception beam measurements that is performed may offer opportunities for the receiver to enter a low power mode (e.g., a (deep) sleep mode).

An advantage of some embodiments is that a beam decision can be taken sooner compared to other approaches.

BRIEF DESCRIPTION OF THE DRAWINGS

Further objects, features and advantages will appear from the following detailed description of embodiments, with reference being made to the accompanying drawings. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the example embodiments. Figure l is a schematic drawing illustrating example principles of beam sweeping according to some embodiments; Figure 2 is a flowchart illustrating example method steps according to some embodiments;

Figure 3 A is a flowchart illustrating example method steps according to some embodiments;

Figure 3B is a flowchart illustrating example method steps according to some embodiments;

Figure 4 is a flowchart illustrating example method steps according to some embodiments;

Figure 5 is a schematic block diagram illustrating an example apparatus according to some embodiments; and

Figure 6 is a schematic drawing illustrating an example computer readable medium according to some embodiments.

DETAILED DESCRIPTION

As already mentioned above, it should be emphasized that the term “comprises/comprising” (replaceable by “includes/including”) when used in this specification is taken to specify the presence of stated features, integers, steps, or components, but does not preclude the presence or addition of one or more other features, integers, steps, components, or groups thereof. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

Embodiments of the present disclosure will be described and exemplified more fully hereinafter with reference to the accompanying drawings. The solutions disclosed herein can, however, be realized in many different forms and should not be construed as being limited to the embodiments set forth herein.

Generally, references to a radio access node may refer to any suitable communication device that provides radio access (e.g., to a user equipment). For example, a radio access node may be a network node, a gNodeB (gNB), a ng-eNB, a base station (BS), a new radio (NR) base station, a transmission reception point (TRP), a relay, an access point (AP), a node of a distributed antenna system (DAS), etc.

Also generally, references to a user equipment may refer to any suitable communication device that is configured to communicate with a radio access node. For example, a user equipment may be a user equipment (UE) as specified by 3 GPP standardization, a station (STA) as specified by IEEE802. i l standardization, etc.

When a “difference” is referred to herein, it is to be understood as representable in any suitable way. For example, a difference between a first and second value may be represented as the second value subtracted from the first value, or as a ratio between the first and second values.

In the following, embodiments will be presented to exemplify the alternative approaches to reception beam sweeping control for beam connection maintenance. Generally, the amount of reception beam measurements performed per duration of time for any of the adapted reception beam sweeping configurations mentioned herein may, according to some embodiments, be lower than a default amount of reception beam measurements performed per duration of time for a default reception beam sweeping configuration. For example, a default reception beam sweeping configuration may define performance of one measurement per transmission-reception beam pair, or any other “full” beam sweeping approach.

Figure 1 schematically illustrates example principles of beam sweeping for a transmitter (TX, e.g., a radio access node) 110 and a receiver (RX, e.g., a user equipment, UE) 120. The transmitter 110 and the receiver 120 may be involved in wireless communication using beamforming. Typically, this involves the transmitter 110 using one (or more) of its available transmission beams 111, 112, 113 for transmission to the receiver 120, and the receiver 120 using one (or more) of its available reception beams 121, 122, 123 for reception from the transmitter 110. Thereby, a beam connection is formed between the transmitter 110 and the receiver 120.

As long as there is no change of conditions affecting the wireless communication, the wireless communication can typically continue reliably using the selected transmission beam(s) and reception beam(s). However, when there is a change of conditions affecting the wireless communication, the selection of transmission beam(s) and reception beam(s) may need to be reevaluated for reliable maintenance of beam connection. To this end, beam sweeping may be used. Generally, beam sweeping may comprise the transmitter 110 transmitting reference signals on each of its available transmission beams 111, 112, 113 and the receiver 120 performing measurements for each of its available reception beams 121, 122, 123.

Typically, beam sweeping may comprise performing reference signal transmission and measurements for each available transmission-reception beam pair under consideration. Thus, using the schematic example of Figure 1, beam sweeping may comprise performing reference signal transmission and measurements for transmission beam 111 combined with reception beam 121, for transmission beam 111 combined with reception beam 122, for transmission beam 111 combined with reception beam 123, for transmission beam 112 combined with reception beam 121, for transmission beam 112 combined with reception beam 122, for transmission beam 112 combined with reception beam 123, for transmission beam 113 combined with reception beam 121, for transmission beam 113 combined with reception beam 122, and for transmission beam 113 combined with reception beam 123.

The transmission is typically performed to make the reference signals of the different available transmission beams 111, 112, 113 distinguishable from each other. For example, the reference signals may be transmitted in different time resources for the different available transmission beams 111, 112, 113. Alternatively or additionally, the measurements for different available reception beams 121, 122, 123 may be performed in different time resources.

In a typical example, the transmitter 110 repeatedly activates one available transmission beam 111, 112, 113 at a time during reference signaling occasions, and - for each transmission beam 111, 112, 113 - the receiver 120 performs measurements using one of the available reception beams 121, 122, 123 at a time.

As already mentioned, beam sweeping may be problematic; e.g., because it causes power consumption at the receiver and beam decision delay. Therefore, it may be desirable to reduce the amount of reception beam measurements that are performed in relation to beam sweeping.

However, such a reduction entails a risk of deteriorating the accuracy of beam decisions (since a reduced amount of reception beam measurements inherently offers a reduced amount of information on which the beam decision should be based). Hence, the amount of reception beam measurements should preferably be reduced only to the extent that sufficient information is still provided for the beam decision.

Thus, some embodiments provide approaches in which the amount of reception beam measurements that are performed in relation to beam sweeping is reduced, while keeping beam decisions sufficiently accurate.

To this end, some embodiments apply one or more (e.g., first and second) adapted reception beam sweeping configuration(s), wherein the adapted reception beam sweeping configuration is obtained by varying (e.g., increasing or decreasing - depending on the circumstances) the amount of reception beam measurements performed per duration of time. Thus, the amount of reception beam measurements performed per duration of time is dynamically adapted according to some embodiments.

Figure 2 illustrates an example method 200 according to some embodiments. The method 200 is a method of controlling reception beam sweeping by a communication device for beam connection maintenance.

In some embodiments, the method 200 is performed by the communication device whose reception beam sweeping is controlled. For example, the method 200 may be performed by the receiver 120 of Figure 1.

Generally, the communication device whose reception beam sweeping is controlled may be any suitable communication device (e.g., a UE, or a radio access node), even if mostly exemplified herein as a UE.

Also generally, beam connection maintenance may refer to any process of keeping reception - and possibly also transmission - beam selection updated (e.g., to avoid link deterioration, loss of connection, etc.). In some embodiments, beam connection maintenance may include performing beam measurements and/or transmission of beam measurement reports to a transmitter node (compare with the transmitter 110 of Figure 1). One example of beam connection maintenance is referred to in 3 GPP (Third Generation Partnership Project) terminology as beam management. The method 200 comprises evaluating values of one or more parameter obtained at the communication device, as illustrated by step 240.

The method 200 also comprises determining whether, for at least one of the one or more parameters, a magnitude of a difference between values (DM) of two or more different time instants exceeds a parameter threshold (PT), as illustrated by step 250.

In response to determining that the magnitude of the difference between values exceeds the parameter threshold (Y-path out of step 250), the method 200 comprises applying an adapted reception beam sweeping configuration for the communication device, as illustrated by step 260. Regardless of whether or not the magnitude of the difference between values exceeds the parameter threshold (Y-path out of step 250 or N-path out of step 250), the method 200 comprises returning to step 240 to repeatedly evaluate values of the one or more parameter. Thereby, the applied reception beam sweeping configuration can be dynamically adapted.

Each of the one or more parameter whose values are evaluated in step 240 is associated with channel conditions for the communication device. For example, a parameter associated with channel conditions for the communication device may be defined as a parameter that has a value that varies with varying channel conditions for the communication device.

Examples of parameters associated with channel conditions include the timing advance associated with the communication device, and the received signal power at the communication device (e.g., the received signal power for reference signals).

When the one or more parameter comprises a timing advance controlled by timing advance commands of a radio access node, determining that the magnitude of the difference between values exceeds the parameter threshold for the timing advance may comprise determining that a magnitude of a difference between a first timing advance value resulting from a first timing advance command of a first time instance and a second timing advance value resulting from a second timing advance command of a second time instance exceeds a timing advance threshold. For example, the amount of reception beam measurements performed per duration of time may be decreased when the magnitude of the difference between the first timing advance value and the second timing advance value is less than the timing advance threshold (i.e., the reception beam measurements may be sparsified when the difference between the first and second timing advance values is relatively small, and/or when there is no difference between the first and second timing advance values). Alternatively or additionally, the amount of reception beam measurements performed per duration of time may be increased when the magnitude of the difference between the first timing advance value and the second timing advance value exceeds the timing advance threshold (i.e., the reception beam measurements may be densified when the difference between the first and second timing advance values is relatively large).

When the one or more parameter comprises a received signal power, determining that the magnitude of the difference between values exceeds the parameter threshold for the received signal power may comprise determining that a magnitude of a difference between a first signal power received at a first time instance and a second signal power received at a second time instance exceeds a received signal power threshold.

In some embodiments, the method 200 also comprises obtaining the values of one or more parameter. Obtaining a parameter value may comprise one or more of: receiving the parameter value (or information indicative of the parameter value), performing measurements to determine the parameter value (or information indicative of the parameter value), and calculating the parameter value (e.g., based on information acquired by reception and/or measurement).

For example, obtaining a timing advance value may comprise receiving a timing advance command from a radio access node and calculating the timing advance value based on the timing advance command.

Alternatively or additionally, obtaining a received signal power value may comprise receiving a signal (e.g., a reference signal) and measuring the power of the received signal.

The magnitude of a difference between values of two or more different time instants considered in step 250 may, for example, be determined by comparing a first value of a parameter obtained at a first time instance with a second value of the parameter obtained at a second, later, time instance. When the first and second values are different, there is a change of values, and the magnitude of the difference between values may be determined as the absolute value of the difference between the first and second values.

In addition to this example, there exist numerous variations of how the magnitude of a difference between values of two or more different time instants can be determined. Some variations will be exemplified in the following, and it should be understood that any one of the disclosed examples may be combined with any other disclosed example, as suitable.

In some embodiments, more than two values of the parameter may be obtained as different time instances, and a difference between values may be considered to be present only when a difference criterion involving more than two values is fulfilled.

For example, a difference between values may be considered to be present when all values obtained in a time interval are different and/or when the difference from one value to the subsequent value has the same sign for all values obtained in a time interval (i.e., when there is no fluctuation between value increase and decrease within the time interval).

Alternatively or additionally, the magnitude of the differences between values may be determined as a function of the absolute values of all differences between subsequent values obtained in a time interval. Example functions include: average, sum, maximum, minimum, ratio, X^th percentile, etc. In one example, the magnitude of the difference between values may be determined as an average of the absolute values of all differences between subsequent values obtained in a time interval. In one (other) example, the magnitude of the difference between values may be determined as a maximum value among the absolute values of all differences between subsequent values obtained in a time interval.

The parameter threshold used in step 250 may be static (e.g., pre-configured by the wireless communication network, or predefined by a RAT standard) or dynamically adjustable (e.g., configured by the wireless communication network via a radio access node, or autonomously configured by the UE).

Dynamic adjustment of the parameter threshold may be realized in any suitable way. For example, dynamic adjustment of the parameter threshold may be realized by the radio access node transmitting the threshold value, or an indication thereof (e.g., a pre-defined identifier of selected from pre-defined identifiers of a plurality of threshold values), to the wireless communication device via a signaling message (e.g., a radio resource control - RRC - message, a medium access control - MAC - message, or a downlink control information - DCI - message). The message can be transmitted in a dedicated message to the wireless communication device or it can be transmitted in a broadcast message (e.g., using system information - SI; such as a master information block - MIB, a system information block type 1 - SIB 1, or another system information block - SIB) to the wireless communication device.

In some embodiments, the parameter threshold value may be adjusted based on a power available for consumption by the communication device. For example, when there is relatively little power available for consumption (e.g., below an available power threshold), the threshold may be set such that a relatively large range of magnitude values lead to application of an adapted reception beam configuration with a relatively low amount of reception beam measurements performed per duration of time. Additionally or alternatively, when there is relatively much power available for consumption (e.g., not below the available power threshold), the threshold may be set such that a relatively large range of magnitude values lead to application of an adapted reception beam configuration with a relatively high amount of reception beam measurements performed per duration of time. The adapted reception beam sweeping configuration applied in step 260 is obtained by varying an amount of reception beam measurements performed per duration of time. For example, the adapted reception beam sweeping configuration may specify an adapted amount of reception beam measurements to be performed per duration of time.

Typically, the variation may be considered in comparison to a default reception beam sweeping configuration. For example, a default reception beam sweeping configuration may specify a default amount of reception beam measurements to be performed per duration of time, wherein the adapted amount of reception beam measurements to be performed per duration of time according to an adapted reception beam sweeping configuration is lower than the default amount of reception beam measurements to be performed per duration of time.

A specification of an amount of reception beam measurements to be performed per duration of time may include information regarding one or more of how many and/or which reception beams to use for beam measurements, how many and/or which transmission beams to investigate by beam measurements, and how many and/or which transmission-reception beam pairs to investigate by beam measurements. Thus, varying the amount of reception beam measurements performed per duration of time may comprise increasing or decreasing a number of reception beams considered, and/or increasing or decreasing a number of transmission beams considered, and/or increasing or decreasing a number of reception beams considered per transmission beam, and/or increasing or decreasing a number of transmission beams considered per reception beam.

Alternatively or additionally, a specification of an amount of reception beam measurements to be performed per duration of time may include information regarding how many beam measurements to perform per reception beam, and/or per transmission beam, and/or per transmission-reception beam pair. The amount of measurements per beam may be the same for all beams subjected to measurements, or may be different for different beams. Thus, varying the amount of reception beam measurements performed per duration of time may comprise increasing or decreasing (for at least one reception beam) a number of reception beam measurements performed for the reception beam.

Alternatively or additionally, a specification of an amount of reception beam measurements to be performed per duration of time may include information regarding how often a beam sweep is to be triggered. Thus, varying the amount of reception beam measurements performed per duration of time may comprise increasing or decreasing a reception beam sweeping rate.

Alternatively or additionally, a specification of an amount of reception beam measurements to be performed per duration of time may include information regarding how many and/or which beam measurements are to be performed per beam sweep. Thus, varying the amount of reception beam measurements performed per duration of time may comprise increasing or decreasing a total number of reception beam measurements performed during a reception beam sweep.

Generally, a beam sweep may be defined in any suitable way. For example, a beam sweep of a default reception beam sweeping configuration may comprise performance of one measurement per transmission-reception beam pair. Alternatively or additionally, a beam sweep of an adjusted reception beam sweeping configuration may comprise performance of one measurement for some transmission-reception beam pairs and no measurement for (the) other transmission-reception beam pairs.

In some embodiments, the method 200 also comprises performing reception beam measurements according to the adapted reception beam sweeping configuration.

Alternatively or additionally, the method 200 also comprises transmitting beam measurement reports to a transmitter node, according to some embodiments.

The method 200 may be selectively performed according to some embodiments.

In some embodiments, the method 200 may be selectively performed depending on a physical downlink control channel (PDCCH) monitoring state of the communication device. For example, the method 200 may be performed (only) when the PDCCH monitoring state stipulates relatively infrequent PDCCH monitoring, and a default reception beam sweeping configuration may be applied when the PDCCH monitoring state stipulates relatively frequent PDCCH monitoring.

The PDCCH monitoring state may be defined as a specific PDCCH monitoring configuration which is configured by the network for the UE (e.g., through radio resource control, RRC, signaling). For example, the UE may be configured to monitor PDCCH every slot, or every other slot, or every four slots, etc. Alternatively or additionally, the PDCCH monitoring state may include that the UE is configured with PDCCH monitoring reduction capabilities. Such PDCCH monitoring reduction configuration may be for a wake-up signal (WUS) outside the active time, such as downlink control information (DCI) format 2-6 according to 3 GPP Release 16 technical specifications. Alternatively or additionally, such PDCCH monitoring reduction configuration may result from the UE receiving an (explicit or implicit) indication to skip monitoring PDCCH for a specific duration, or to adapt its PDCCH monitoring periodicity,

Alternatively or additionally, the method 200 may be selectively performed depending on a mobility status of the communication device. For example, the method 200 may be performed (only) when the mobility status (e.g., mobility state) indicates that the communication device is stationary or moves relatively slowly (e.g., low/medium speed mode), and a default reception beam sweeping configuration may be applied when the mobility status indicates that the communication device moves relatively fast (e.g., high speed mode). The mobility status of the communication device may be obtained in any suitable way. For example, the mobility status of the communication device may be determined autonomously by the communication device and/or by another node (e.g., a radio access node) serving or managing the communication device. In the latter case, the radio access node may transmit information related to the speed of the communication device to the communication device via signaling (e.g., via RRC, DCI, or MAC, signaling).

The mobility status determination may be based on one or more rules, according to some embodiments.

According to one rule, the communication device may be considered to be stationary when the received signal level at the communication device from a cell (e.g., serving cell) does not change by more than certain, first, margin over a certain, first, time period. Alternatively or additionally, the communication device may be considered to be moving with low speed when the received signal level at the communication device from a cell (e.g., serving cell) does not change by more than certain, second (other), margin over a certain, second (possibly other), time period. Yet alternatively or additionally, the communication device may be considered to be moving with medium or high speed when not considered stationary or moving with low speed. For example, the communication device may be considered to be moving with medium or high speed when the received signal level at the communication device from a cell (e.g., serving cell) changes by more than a certain (e.g., the first, and/or the second) margin over a certain (e.g., the first, and/or the second) time period.

According to one rule, the communication device may be considered to be stationary when the speed of the communication device is zero, or close to zero (e.g., below a certain, first, threshold). Alternatively or additionally, the communication device may be considered to be moving with low speed when the speed of the communication device is below a certain, second, threshold. Yet alternatively or additionally, the communication device may be considered to be moving with medium or higher speed when not considered stationary or moving with low speed. For example, the communication device may be considered to be moving with medium or high speed when the speed of the communication device is not below a certain (e.g., the first and/or the second) threshold.

The speed of the communication device can be expressed in terms of distance per unit time and/or in terms of Doppler frequency.

The speed of the communication device in terms of distance per unit time can be determined by the communication device and/or by another node (e.g., a serving radio access node) by estimating whether changes in the received signal level (e.g., signal strength, path loss, reference symbol received power - RSRP, signal quality, reference symbol received quality - RSRQ, signal-to- interference-and-noise ratio - SINR, reference signal signal-to-interference-and-noise ratio - RS- SINR, etc.) of signals transmitted between the communication device and the other node exceeds a certain margin over a certain time period.

The speed of the communication device in terms of Doppler frequency can be determined by the communication device and/or by another node (e.g., a serving radio access node) by estimating one or more radio channel characteristics of the signals transmitted between the communication device and the other node. Alternatively or additionally, the method 200 may be selectively performed depending on a user equipment (UE) power class used for operation by the communication device. For example, the method 200 may be performed (only) when the UE power class relates to mobile operations of the communication device, and a default reception beam sweeping configuration may be applied when the UE power class relates to fixed operations of the communication device. Alternatively or additionally, the method 200 may be performed (only) when the UE power class indicates that the communication device has relatively strict requirements on power consumption (e.g., using energy harvesting, or being powered by a non- chargeable battery), and a default reception beam sweeping configuration may be applied otherwise; when the UE power class indicates that the communication device does not have relatively strict requirements on power consumption.

Alternatively or additionally, the method 200 may be selectively performed for one or more (neighbor or serving) cell with intra-frequency reception beam measurements, depending on received signal power value. For example, the method 200 may be performed for such cell(s) (only) when the received signal power is relatively high (e.g., exceeds an intra-frequency power threshold), and a default reception beam sweeping configuration may be applied otherwise; when the received signal power is not relatively high. Generally, intra-frequency measurements may be performed for handover decisions (e.g., to determine whether to change serving cell for a current carrier frequency), for example.

Alternatively or additionally, the method 200 may be selectively performed for one or more neighbor cell with inter-frequency reception beam measurements, depending on received signal power value. For example, the method 200 may be performed for such cell(s) (only) when the received signal power is relatively high (e.g., exceeds an inter-frequency power threshold), and a default reception beam sweeping configuration may be applied otherwise; when the received signal power is not relatively high. Generally, inter-frequency measurements may be performed for handover decisions (e.g., to determine whether to change carrier frequency for a current serving cell and/or change serving cell for another carrier frequency), for example.

Alternatively or additionally, the method 200 may be selectively performed depending on the type of traffic which is ongoing for the UE. For example, the method 200 may be performed (only) when a fifth generation (5G) quality or service (QoS) indicator (5QI) value indicates that the traffic is not delay sensitive (e.g., the UE may choose to not perform the method 200 during a conversational voice session identified by 5QI 1).

The above examples of selective performance of the method 200 may be combined, as suitable. For example, the method 200 may be selectively performed depending on a PDCCH monitoring state and a mobility status of the communication device (e.g., the method 200 being performed (only) when the PDCCH monitoring state stipulates relatively infrequent PDCCH monitoring AND the mobility status indicates that the communication device is stationary or moves relatively slowly).

A single adapted reception beam sweeping configuration may be applicable according to some embodiments. Alternatively, the adapted reception beam sweeping configuration applied in step 260 may be one of a plurality of (e.g., two or more) adapted reception beam sweeping configurations.

For example, the adapted reception beam sweeping configuration applied in step 260 may be a first adapted reception beam sweeping configuration (“Procedure A”), and a second adapted reception beam sweeping configuration (“Procedure B”) may be applied in response to determining that the magnitude of the difference between values of two or more different time instants does not exceed the parameter threshold. Typically, the amount of reception beam measurements performed per duration of time for the first adapted reception beam sweeping configuration may be higher than the amount of reception beam measurements performed per duration of time for the second adapted reception beam sweeping configuration. Put differently, the second adapted reception beam sweeping configuration (Procedure B) is more relaxed, or decreased, in its reception beam sweeping configuration than the first adapted reception beam sweeping configuration (Procedure A).

In some embodiments, a plurality of thresholds are applied in an extension of step 250 to determine which of a plurality of adapted reception beam sweeping configurations to apply. Typically, the amount of reception beam measurements performed per duration of time increases with increasing magnitude of difference between values of two or more different time instants.

Letting the number of thresholds increase towards infinity renders embodiments where the mapping between magnitude of difference between values of two or more different time instants and adapted reception beam sweeping configurations approaches a continuous function transformation.

Figures 3A, 3B, and 4 exemplify some variations on embodiments with first and second adapted reception beam sweeping configurations. Figure 3A illustrates an example method 300a according to some embodiments. The method 300a is a method of controlling reception beam sweeping by a communication device for beam connection maintenance.

In some embodiments, the method 300a is performed by the communication device whose reception beam sweeping is controlled. For example, the method 300a may be performed by the receiver 120 of Figure 1.

Alternatively or additionally, the method 300a may, according to some embodiments, be seen as an exemplification of the method 200.

In optional step 310a, a default reception beam sweeping configuration is applied, and optional step 320a illustrates that the remainder of the method steps may be selectively performed (e.g., as exemplified above for the method 200 of Figure 2).

When the default reception beam sweeping configuration should continue to be applied (i.e., when adaptive beam sweeping should not be applied; N-path out of step 320a), the method 300a returns to step 310a. When the remainder of the method steps should be performed (i.e., when adaptive beam sweeping should be applied; Y-path out of step 330a), the method 300a continues to optional step 330a.

In optional step 330a, values of one or more parameter associated with channel conditions for the communication device are obtained (e.g., as exemplified above for method 200 of Figure 2).

In step 340a, values of the one or more parameter (e.g., timing advance and/or received signal power) are evaluated (compare with step 240 of Figure 2).

In step 350a, it is determined whether, for at least one of the one or more parameters, a magnitude of a difference between values (DM) of two or more different time instants exceeds a parameter threshold (PT) (compare with step 250 of Figure 2).

When the magnitude of the difference between values exceeds the parameter threshold (Y-path out of step 350a), the method 300a comprises applying an adapted reception beam sweeping configuration with relatively high amount of reception beam measurements per duration of time (e.g., the first adapted reception beam sweeping configuration as described above), as illustrated by step 360a (compare with step 260 of Figure 2).

When the magnitude of the difference between values does not exceed the parameter threshold (N- path out of step 350a), the method 300a comprises applying an adapted reception beam sweeping configuration with relatively low amount of reception beam measurements per duration of time (e.g., the second adapted reception beam sweeping configuration as described above), as illustrated by step 370a. Thus, according to the method 300a, any change in values (increase or decrease) trigger application of an adapted beam sweeping configuration with relatively high amount of reception beam measurements per duration of time.

Regardless of whether or not the magnitude of the difference between values exceeds the parameter threshold (Y-path out of step 350a or N-path out of step 350a), the method 300a comprises repetition for dynamic adaption. For example, the method 300a may - after steps 360a and 370a - return to optional step 330a and/or (e.g., more seldom) to optional step 320a.

In some embodiments, the method 300a also comprises performing reception beam measurements according to the applied (adapted or default) reception beam sweeping configuration.

Alternatively or additionally, the method 300a also comprises transmitting beam measurement reports to a transmitter node, according to some embodiments.

Figure 3B illustrates an example method 300b according to some embodiments. The method 300b is a method of controlling reception beam sweeping by a communication device for beam connection maintenance.

In some embodiments, the method 300b is performed by the communication device whose reception beam sweeping is controlled. For example, the method 300b may be performed by the receiver 120 of Figure 1.

Alternatively or additionally, the method 300b may, according to some embodiments, be seen as an exemplification of the method 200.

The method 300b may be particularly suitable when received signal power is one of the one or more evaluated parameters.

In optional step 310b, a default reception beam sweeping configuration is applied, and optional step 320b illustrates that the remainder of the method steps may be selectively performed (e.g., as exemplified above for the method 200 of Figure 2).

When the default reception beam sweeping configuration should continue to be applied (i.e., when adaptive beam sweeping should not be applied; N-path out of step 320b), the method 300b returns to step 310b. When the remainder of the method steps should be performed (i.e., when adaptive beam sweeping should be applied; Y-path out of step 330b), the method 300b continues to step 325b.

In step 325b, it is determined whether the received signal power (P) exceeds an initiation threshold (T). When the received signal power exceeds the initiation threshold (Y-path out of step 325b), the method 300b comprises initially applying an adapted reception beam sweeping configuration with relatively low amount of reception beam measurements per duration of time (e.g., the second adapted reception beam sweeping configuration as described above), as illustrated by step 370b. When the received signal power does not exceed the initiation threshold (N-path out of step 325b), the method 300b comprises initially applying an adapted reception beam sweeping configuration with relatively high amount of reception beam measurements per duration of time (e.g., the first adapted reception beam sweeping configuration as described above), as illustrated by step 360b. Regardless of whether or not the received signal power exceeds the initiation threshold (Y-path out of step 325b to step 370b, or N-path out of step 325b to step 360b), the method 300b then continues to optional step 330b.

In optional step 330b, values of one or more parameter associated with channel conditions for the communication device are obtained (e.g., as exemplified above for method 200 of Figure 2).

In step 340b, values of the one or more parameter (e.g., at least received signal power) are evaluated (compare with step 240 of Figure 2).

In step 350b, it is determined whether, for at least one of the one or more parameters (e.g., for at least the received signal power), a magnitude of a difference between values (DM) of two or more different time instants exceeds a parameter threshold (PT) (compare with step 250 of Figure 2). When the magnitude of the difference between values does not exceed the parameter threshold (N- path out of step 350b), no change to the applied adapted reception beam sweeping is made and the method 300b returns to step 330b.

When the magnitude of the difference between values exceeds the parameter threshold (Y-path out of step 350b), the method 300b proceeds to step 355b, where it is determined whether the difference between values for the parameter (e.g., the received signal power) constituted a decrease or an increase.

When the difference between values for the parameter constituted a decrease (Y-path out of step 355b) the method 300b comprises applying an adapted reception beam sweeping configuration with relatively high amount of reception beam measurements per duration of time (e.g., the first adapted reception beam sweeping configuration as described above), as illustrated by step 360b. This may correspond to increasing the amount of reception beam measurements performed per duration of time when the signal power decreases.

Otherwise, when the difference between values for the parameter constituted an increase (N-path out of step 355b), the method 300b comprises applying an adapted reception beam sweeping configuration with relatively low amount of reception beam measurements per duration of time (e.g., the second adapted reception beam sweeping configuration as described above), as illustrated by step 370b. This may correspond to decreasing the amount of reception beam measurements performed per duration of time when the signal power increases.

Thus, when the one or more parameter comprises a received signal power, determining that the magnitude of the difference between values of two or more different time instants exceeds the parameter threshold for the received signal power (Y-path out of step 350b) may comprise determining that a magnitude of a difference between a first signal power received at a first time instance and a second signal power received at a second, later, time instance exceeds a received signal power threshold.

Furthermore, it may be determined whether the second signal power is higher than the first signal power (i.e., increasing signal power) or the first signal power is higher than the second signal power (i.e., decreasing signal power), as illustrated by 355b.

Applying the adapted reception beam sweeping configuration may comprise decreasing the amount of reception beam measurements performed per duration of time when the second signal power is higher than the first signal power, and increasing the amount of reception beam measurements performed per duration of time when the first signal power is higher than the second signal power.

In some embodiments, a change of amount of reception beam measurements performed per duration of time is dependent of the currently used reception beam sweeping configuration.

For example, when an adapted reception beam sweeping configuration with relatively low amount of reception beam measurements per duration of time is being used and it is determined that the first signal power is higher than the second signal power (Y-path out of step 355b), applying the adapted reception beam sweeping configuration may comprise increasing the amount of reception beam measurements performed per duration of time. When an adapted reception beam sweeping configuration with relatively high amount of reception beam measurements per duration of time is being used and it is determined that the first signal power is not higher than the second signal power (i.e., the second signal power is higher than the first signal power; N-path out of step 355b), applying the adapted reception beam sweeping configuration may comprise decreasing the amount of reception beam measurements performed per duration of time. Otherwise, when an adapted reception beam sweeping configuration with relatively low amount of reception beam measurements per duration of time is being used and it is determined that the first signal power is not higher than the second signal power, and/or when an adapted reception beam sweeping configuration with relatively high amount of reception beam measurements per duration of time is being used and it is determined that the first signal power is higher than the second signal power, the adapted reception beam sweeping configuration may be left unchanged.

Thus, according to the method 300b, a change in values that comprise a decrease in values trigger application of an adapted beam sweeping configuration with relatively high amount of reception beam measurements per duration of time, while a change in values that comprise an increase in values trigger application of an adapted beam sweeping configuration with relatively low amount of reception beam measurements per duration of time. The method 300b comprises repetition for dynamic adaption. For example, the method 300b may - after steps 360b and 370b - return again to optional step 330b and/or (e.g., more seldom) to optional step 320b (not shown in Figure 3B).

In some embodiments, the method 300b also comprises performing reception beam measurements according to the applied (adapted or default) reception beam sweeping configuration.

Alternatively or additionally, the method 300b also comprises transmitting beam measurement reports to a transmitter node, according to some embodiments.

Figure 4 illustrates an example method 400 according to some embodiments. The method 400 is a method of controlling reception beam sweeping by a communication device for beam connection maintenance.

In some embodiments, the method 400 is performed by the communication device whose reception beam sweeping is controlled. For example, the method 400 may be performed by the receiver 120 of Figure 1.

Alternatively or additionally, the method 400 may, according to some embodiments, be seen as an exemplification of the method 200 and/or the method 300a.

In steps 431 and 432, values of one or more parameter associated with channel conditions for the communication device are obtained (e.g., as exemplified above for method 200 of Figure 2; compare with step 330a of Figure 3A). More precisely, first and second timing advance commands (TAI and TA2, respectively) are received at first and second time instants, respectively, and corresponding timing advance values (NTAI and NTA2, respectively) are determined.

In step 440, values of the one or more parameter are evaluated (compare with step 240 of Figure

2 and/or step 340a of Figure 3A). More precisely, timing advance values NTAI and NTA2 are compared.

In step 450, it is determined whether a magnitude of a difference between values of two or more different time instants exceeds a parameter threshold (compare with step 250 of Figure 2 and/or step 350a of Figure 3 A). More precisely, it is determined whether the magnitude of a difference between timing advance values |NTA2 - NTAI| exceeds a timing advance threshold (Hl).

When the magnitude of the difference between values for the timing advance does not exceed the parameter threshold (N-path out of step 450), the method 400 comprises applying an adapted reception beam sweeping configuration with relatively low amount of reception beam measurements per duration of time (e.g., the second adapted reception beam sweeping configuration as described above), as illustrated by step 470 (compare with step 370a of Figure

3 A). This may correspond to decreasing the amount of reception beam measurements performed per duration of time when the magnitude of the difference between the first timing advance value and the second timing advance value is less than the timing advance threshold. When the magnitude of the difference between values for the timing advance exceeds the parameter threshold (Y-path out of step 450), the method 400 may comprise applying an adapted reception beam sweeping configuration with relatively high amount of reception beam measurements per duration of time (e.g., the first adapted reception beam sweeping configuration as described above), as illustrated by step 460 (compare with step 360a of Figure 3 A). This may correspond to increasing the amount of reception beam measurements performed per duration of time when the magnitude of the difference between the first timing advance value and the second timing advance value exceeds the timing advance threshold.

Generally, a change in timing advance (e.g., manifested via different timing advance values NTA at different time instants) indicates that the distance (e.g., geographical distance and/or radio path length) between the communication device and the radio access node has changed. Thus, when there is a large enough change in timing advance (e.g., when a magnitude of difference between timing advance values exceeds a timing advance threshold), it indicates that the communication device is moving and that beam measurements typically need to be performed more often (e.g., to ensure proper beam tracking). Correspondingly, when there is no particularly large change in timing advance (e.g., when a magnitude of difference between timing advance values does not exceed a timing advance threshold), it indicates that it is possible/likely that the communication device is relatively stationary. In relatively stationary conditions, any information needed for proper beam management (e.g., beam tracking) changes relatively slowly - if at all - and beam measurements typically need not be performed particularly often.

In some embodiments, the method first proceeds to optional step 451 when the magnitude of the difference between values for the timing advance exceeds the parameter threshold (Y-path out of step 450).

In step 451 , it is determined - for another parameter - whether a magnitude of a difference between values of two or more different time instants exceeds a parameter threshold (compare with step 250 of Figure 2 and/or step 350a of Figure 3 A). More precisely, it is determined whether the magnitude of a difference between received signal power values |P2 - P 11 exceeds a received signal power threshold (H2), where Pl is the received signal power at the first time instant and P2 is the received signal power at the second time instant.

When the magnitude of the difference between values for the received signal power does not exceed the parameter threshold (N-path out of step 451), the method 400 comprises applying an adapted reception beam sweeping configuration with relatively low amount of reception beam measurements per duration of time (e.g., the second adapted reception beam sweeping configuration as described above), as illustrated by step 470 (compare with step 370a of Figure 3A). When the magnitude of the difference between values for the received signal power exceeds the parameter threshold (Y-path out of step 451), the method 400 comprises applying an adapted reception beam sweeping configuration with relatively high amount of reception beam measurements per duration of time (e.g., the first adapted reception beam sweeping configuration as described above), as illustrated by step 460 (compare with step 360a of Figure 3A).

Thus, in some embodiments, the adapted reception beam sweeping configuration with relatively high amount of reception beam measurements per duration of time is only used when there is a relatively large difference between values of two or more different time instants for both timing advance and received signal power.

In some embodiments, the adapted reception beam sweeping configuration(s) are only considered as long as the communication device is considered to be in time synchronization with a corresponding radio access node. Time synchronization may, for example, be indicated by a time alignment timer (TAT). While the time alignment timer is running, it is assumed that the communication device is in time synchronization. When the time alignment timer has expired, it is not assumed that the communication device is in time synchronization.

This is illustrated in optional step 420, where it is determined whether the communication device is in time synchronization. For example, step 420 may comprise determining whether the time alignment timer is running (i.e., has not expired). When the communication device is in time synchronization (e.g., when the time alignment counter is running; Y-path out of step 420), the method proceeds to step 440 for consideration of the adapted reception beam sweeping configuration(s). When the communication device is (of risk of being) not in time synchronization (e.g., when the time alignment counter has expired; N-path out of step 420), the method proceeds to optional step 410 for application of a default reception beam sweeping configuration (compare with step 310a of Figure 3 A).

The method 400 may be performed repeatedly for dynamic adaption. For example, the method 400 may - after steps 410, 460, and 470 - return steps 431 and 432.

In some embodiments, the method 400 also comprises performing reception beam measurements according to the applied (adapted or default) reception beam sweeping configuration.

Alternatively or additionally, the method 400 also comprises transmitting beam measurement reports to a transmitter node, according to some embodiments.

Typically, one or more (e.g., all) steps described above in connection with Figures 2, 3 A, 3B, and 4 are performed autonomously by the communication device (compare with the receiver 120 of Figure 1).

It should be noted that any feature(s) described in connection to one of the Figures 2, 3 A, 3B, and 4 may be equally applicable (as suitable) - in isolation or in association with other feature(s) described in connection thereto - to the context of any other one(s) of the Figures 2, 3 A, 3B, and 4; even if not explicitly mentioned in connection thereto.

Figure 5 schematically illustrates an example apparatus 500 according to some embodiments. The apparatus 500 is for controlling reception beam sweeping by a communication device for beam connection maintenance.

In some embodiments, the apparatus 500 is comprised, or comprisable, in the communication device (CD; e.g., a user equipment, UE, or a radio access node) 510 whose reception beam sweeping is controlled. For example, the apparatus may be comprised in the receiver 120 of Figure 1.

Alternatively or additionally, the apparatus 500 may, according to some embodiments, be configured to cause execution of (e.g., execute) one or more method steps as described in connection to any of the methods 200, 300a, 300b, and 400 described in connection to Figures 2, 3 A, 3B, and 4, respectively.

The communication device 510 comprises a transceiver (TX/RX; e.g., transceiving circuitry or a transceiver module) 530, a beam former (BF; e.g., beam forming circuitry or a beam form module) 540, and a beam sweep configurer (BSC; e.g., beam sweep configuring circuitry or a beam sweep configuration module) 550.

The transceiver 530 is configured to transmit and receive signals according to any suitable approach. The beam former 540 is configured to control the transceiver 530 to apply selected transmission and/or reception beam(s); as suitable. The beam sweep configurer 550 is configured to control the selection of transmission and/or reception beam(s) by the beam former 540 for beam sweep execution.

The apparatus 500 comprises a controller (CNTR; e.g., controlling circuitry or a control module) 520.

The controller 520 is configured to cause repeated evaluation of values of one or more parameter obtained at the communication device (compare with step 240 of Figure 2, step 340a of Figure 3 A, step 340b of Figure 3B, and step 440 of Figure 4), wherein the one or more parameter is associated with channel conditions for the communication device.

To this end, the controller 520 may comprise, or be otherwise associated with (e.g., connected, or connectable, to) an evaluator (EV; e.g., evaluating circuitry or an evaluation module) 523. The evaluator 523 may be configured to repeatedly evaluate values of one or more parameter obtained at the communication device.

The controller 520 may be further configured to cause obtaining of values of the one or more parameter(s) (compare with step 330a of Figure 3 A, step 330b of Figure 3B, and steps 431 and 432 of Figure 4). As mentioned earlier, obtaining of a parameter value may comprise one or more of: reception of the parameter value (or information indicative of the parameter value), performance of measurements to determine the parameter value (or information indicative of the parameter value), and calculation of the parameter value (e.g., based on information acquired by reception and/or measurement).

To this end, the controller 520 may comprise, or be otherwise associated with (e.g., connected, or connectable, to) an obtainer (OBT; e.g., obtaining circuitry or an obtaining module) 522. The obtainer 522 may be configured to obtain values of the one or more parameter(s). For example, the obtainer may be configured to receive the parameter value (or information indicative of the parameter value) via the transceiver 530, and/or perform measurements to determine the parameter value (or information indicative of the parameter value), and/or calculate the parameter value (e.g., based on information acquired by reception and/or measurement).

The controller 520 is also configured to cause determination of whether, for at least one of the one or more parameters, a magnitude of a difference between values of two or more different time instants exceeds a parameter threshold (compare with step 250 of Figure 2, step 350a of Figure 3 A, step 350b of Figure 3B, and steps 450 and 451 of Figure 4).

To this end, the controller 520 may comprise, or be otherwise associated with (e.g., connected, or connectable, to) a determiner (DET; e.g., determining circuitry or a determination module) 524. The determiner 524 may be configured to determine whether, for at least one of the one or more parameters, a magnitude of a difference between values of two or more different time instants exceeds a parameter threshold.

The controller 520 is also configured to cause (in response to determination that the magnitude of the difference between values exceeds the parameter threshold) application of an adapted reception beam sweeping configuration for the communication device (compare with step 260 of Figure 2, steps 360a and 370a of Figure 3 A, steps 360b and 370b of Figure 3B, and steps 460 and 470 of Figure 4), wherein the adapted reception beam sweeping configuration is obtained by varying an amount of reception beam measurements performed per duration of time.

When the adapted reception beam sweeping configuration applied in response to determination that the magnitude of the difference between values exceeds the parameter threshold is a first adapted reception beam sweeping configuration (compare with step 360a of Figure 3 A, and step 460 of Figure 4), the controller 520 may be further configured to cause (in response to determination that the magnitude of the difference between values does not exceed the parameter threshold) application of a second adapted reception beam sweeping configuration for the communication device (compare with step 370a of Figure 3 A, and step 470 of Figure 4), wherein the amount of reception beam measurements performed per duration of time for the first adapted reception beam sweeping configuration is higher than the amount of reception beam measurements performed per duration of time for the second adapted reception beam sweeping configuration.

To this end, the controller 520 may comprise, or be otherwise associated with (e.g., connected, or connectable, to) an adaptor (AD; e.g., adapting circuitry or an adaptation module) 525. The adaptor 525 may be configured to apply an adapted reception beam sweeping configuration for the communication device based on the determination of whether the magnitude of the difference between values exceeds the parameter threshold.

The controller 520 is typically configured to cause the application of adapted reception beam sweeping configuration(s) via the beam sweep configurer 550. For example, the adaptor 525 may be configured to control the beam sweep configurer 550 to apply the adapted reception beam sweeping configuration(s).

The controller 520 may be further configured to cause performance of reception beam measurements according to the adapted reception beam sweeping configuration and/or transmission of beam measurement reports.

In some embodiments, the controller 520 is configured to cause selective application of adaptive reception beam sweeping (compare with step 320a of Figure 3 A, step 320b of Figure 3B, and step 420 of Figure 4). As mentioned earlier, the selectiveness may be based on one or more of PDCCH monitoring state, received signal power value, mobility status, UE power class, and time synchronization status. The time synchronization status may, for example, be indicated by a time alignment timer (TIM) 560 as explained above.

To this end, the controller 520 may comprise, or be otherwise associated with (e.g., connected, or connectable, to) a selector (SEL; e.g., selecting circuitry or a selection module) 521. The selector 521 may be configured to apply the adaptive reception beam sweeping selectively.

It should be noted that any feature(s) described in connection to any of the Figures 2, 3 A, 3B, and 4 may be equally applicable - in isolation or in association with other feature(s) described in connection thereto - to the context of Figure 5; even if not explicitly mentioned in connection thereto.

In the following, a few case studies will be disclosed as illustrative examples of scenarios where some embodiments may be practiced. It should be noted that any feature(s) described in connection to any of these case studies may be equally applicable (as suitable) - in isolation or in association with other feature(s) described in connection thereto - to the context of any of the more general embodiments described in connection to Figures 2, 3 A, 3B, and 4; even if not explicitly mentioned in connection thereto.

Beamforming can be beneficial, for example, to improve the coverage for transmission of reference signals (RSs), such as, synchronization signal (SS) and physical broadcast channel (PBCH) blocks (referred to as synchronization signal blocks, SSB, in 3GPP). Other examples of downlink (DL) reference signals include: channel state information reference signals (CSI-RS), cell-specific reference signals (CRS), demodulation reference signals (DMRS), primary synchronization signals (PSS), secondary synchronization signals (SSS), discovery reference signals (DRS), positioning reference signals (PRS), etc. The benefits of beamforming may be particularly prominent in high carrier frequency bands, where it has the potential of compensating for high path loss.

In new radio (NR; advocated by the 3 GPP), beamforming and beam sweeping for SSB transmission may be supported in that a radio access node providing a communication cell can transmit multiple SSBs using respective (different) beams in a time multiplexed fashion.

These transmissions are typically confined to a time interval of a half frame (5 ms). The maximum number of SSBs within a half frame may be denoted by L, and typically depends on the used frequency band. Some examples include: L=4 for licensed frequency division duplex (FDD) bands and carrier frequencies not larger than 3 GHz, L=8 for licensed FDD bands and carrier frequencies larger than 3 GHz, L=4 for licensed time division duplex (TDD) bands and carrier frequencies not larger than 1.88 GHz, L=8 for licensed TDD bands and carrier frequencies larger than 1.88 GHz within frequency range 1 (FR1), and L=64 for licensed TDD bands and carrier frequencies within frequency range 2 (FR2).

A thus transmitted SSB may be referred to as a (transmission) beam, a DL beam, a DL reference signal beam, a spatial filter, a spatial domain transmission filter, a main lobe of the antenna array radiation pattern, etc.

In a typical scenario, each SSB carries NR-PSS, NR-SSS, and NR-PBCH in four successive symbols, and one or more SSBs are transmitted in one SSB burst, wherein the SSB burst is repeated with certain periodicity (e.g., 5 ms, 10 ms, 20 ms, 40 ms, 80 ms, or 160 ms).

The UE is typically configured to perform measurements on DL and/or UL reference signals (RSs) of one or more communication cells. Examples of DL RSs include SSB, CSLRS, signals in SSB (e.g. PSS, SSS, DMRS, etc.), DMRS, PRS, etc., and examples of UL RSs include sounding reference signals (SRS), DMRS, etc. Examples of measurements performed on both DL RSs and UL RSs include UE reception-transmission (Rx-Tx) time difference, gNB reception-transmission (Rx-Tx) time difference, etc., examples of measurements performed only on DL RSs include RSRP, RSRQ, RS-SINR, reference signal time difference (RSTD), etc., and examples of measurement performed only on UL RSs include uplink relative time of arrival of signals, angle of arrival of signals, etc. Typically, the UE may be configured to perform such measurements in different UE activity states (e.g., radio resource control - RRC - idle state, RRC inactive state, RRC connected state, etc.). This type of measurements may be seen as an example of reception beam measurements during beam sweeping, and may be used for beam connection maintenance, for example. Alternatively or additionally, a UE may perform measurements on sidelink reference signals (e.g., transmitted from another UE); which may also be seen as an example of reception beam measurements during beam sweeping.

Generally, the measured cell may belong to, or operate on, the same carrier frequency as the serving cell (e.g., intra-frequency carrier) or it may belong to, or operate on, a different carrier frequency than the serving cell (e.g., non-serving carrier). A non-serving carrier may be referred to as inter-frequency carrier if the serving cell and the measured cell belong to the same radio access technology (RAT), and may be referred to as inter-RAT carrier if the serving cell and the measured cell belong to different RATs.

The UE may be configured with information about SSB transmission on one or more communication cells, wherein the information may take the form of one or more SS/PBCH block measurement timing configuration (SMTC). The SMTC comprises parameters such as SMTC periodicity, SMTC occasion length (specified in time and/or duration), SMTC time offset with regard to a reference time (e.g., the system frame number, SFN, of the serving cell), etc. The SMTC periodicity may, for example, be the same as the periodicity of the SSB burst.

The UE is typically configured by the network (e.g., via a RRC message) with a measurement configuration (e.g., specifying measurement gap pattern, carrier frequency, type of measurements, higher layer filtering coefficient, etc.).

The UE may also be configured by the network (e.g., via a RRC message) with a measurement reporting configuration (e.g., specifying time to trigger report, and reporting mechanism such as periodic and/or event triggered reporting).

The SMTC and/or the measurement configuration may be seen as an example of a (default) reception beam sweeping configuration, and may be adapted as exemplified herein.

Various types of measurements (e.g., on reference signals) may be performed by the UE. Examples include: cell identification (e.g., physical cell identity - PCI - acquisition, PSS/SSS detection, cell detection, cell search, etc.), reference symbol received power (RSRP), reference symbol received quality (RSRQ), secondary synchronization RSRP (SS-RSRP), secondary synchronization RSRQ (SS-RSRQ), signal-to-interference-and-noise ratio (SINR), reference signal SINR (RS-SINR), secondary synchronization SINR (SS-SINR), channel state information RSRP (CSI-RSRP), channel state information RSRQ (CSI-RSRQ), received signal strength indicator (RSSI), system information (SI) acquisition, cell global identity (CGI) acquisition, reference signal time difference (RSTD), UE reception-transmission (RX-TX) time difference measurement, radio link quality, radio link monitoring (RLM), out of synchronization (out of sync) detection, in synchronization (in-sync) detection, Layer- 1 RSRP (LI -RSRP), Layer- 1 SINR (LI -SINR), etc. The measurements performed by the UE may have various purposes, including beam connection maintenance. Other example purposes of measurements performed by the UE include: UE mobility (e.g., cell change, cell selection, cell reselection, handover, RRC connection reestablishment, etc.), UE positioning and/or location determination, self-organizing network (SON), minimization of drive tests (MDT), operation and maintenance (O&M), network planning and optimization, etc.

As already mentioned, beam sweeping can improve the coverage for UE measurements. However, use of beam sweeping typically increases UE power consumption and/or measurement delay.

This increase may be exemplified by radio resource management (RRM) measurements, which are typically averaged over multiple samples (e.g., 5 or 10 samples) depending on type of measurements.

Alternatively or additionally, this increase may be exemplified by FR2 measurements for a UE with eight reception beams, where each beam is swept by the UE every 160 ms to cover all possible spatial directions. Thus, it takes at least 1280 ms to perform a full beam sweep and identify a suitable beam (i.e., to make a beam decision; select a beam to provide a robust communication link).

Yet alternatively or additionally, this increase may be exemplified by a multi-beam deployment, where the UE typically takes the same number of samples from each beam of a cell; irrespective of the quality of the individual beams. Thus, depending on quality variations between beams, the UE might be spending an unnecessary amount of measurement occasions on beams with comparatively high quality.

To mitigate the increase in UE power consumption and/or measurement delay, full beam sweeping (and beam sweeping in general) should be done cautiously (i.e., performed only when, and to the extent, needed for adequate performance). Some embodiments provide approaches to accomplish this task.

In a first example case study (which may be seen as an exemplification of the method 300a of Figure 3 A and/or the method 400 of Figure 4), a timing advance is used to determine to what extent the reception beam sweeping should be adapted (e.g., how much the amount of reception beam measurements performed per time duration should be reduced compared to a default reception beam sweeping configuration).

Timing advance is related to time alignment between a radio access node and a UE. In the context of NR, time alignment may be exemplified in that the UE starts uplink (UL) transmission in radio frame number i before the start of the corresponding downlink (DL) radio frame i at the UE. The time difference between UL transmission start and DL radio frame start may be denoted by A_TA + A_TA offset) T_c seconds where T_c « 0.51 ns (which is a basic time unit in NR). The parameter W_TA offset is configurable and depends on the duplex mode of the cell in which the uplink transmission takes place and the used frequency range (FR). The parameter N_TA depends on a timing advance (TA) command sent to the UE by the radio access node, and may implement an adjustment step size that depends on the subcarrier spacing (SCS) of the uplink signal. Reception of a timing advance command may restart a time alignment timer which indicates whether the UE (specifically layer 1, LI) can be considered to be time synchronized or not: LI is considered synchronized when the timer is running, and LI is considered non-synchronized otherwise; when the timer is not running.

In the first example case study, the UE determines the difference between parameter values (NTAI and NTA2 which are instantiations of 1V_TA) related to the corresponding timing advance commands (TAI and TA2) obtained by the UE at first and second time instances (T1 and T2), respectively, and adapts the reception beam sweeping configuration (i.e., the amount of reception beam measurements performed per duration of time according to the measurement procedure) based on the determined difference.

More specifically, the UE performs measurements according to the first adapted reception beam sweeping configuration, “Procedure A”, (compare with step 460 of Figure 4) when |NTA2 - NTAI|>H1, where Hl is a predefined or configurable threshold (compare with step 450 of Figure 4). Thus, the UE performs measurements according to the first adapted reception beam sweeping configuration when the magnitude of the difference between parameter values NTAI and NTA2 related to the corresponding timing advance commands TAI and TA2 obtained by the UE at first and second time instances T1 and T2 exceeds (or is equal to) the threshold HL Otherwise, when the magnitude of the difference between parameter values NTAI and NTA2 related to the corresponding timing advance commands TAI and TA2 obtained by the UE at first and second time instances T1 and T2 is less than the threshold Hl, UE performs measurements according to the second adapted reception beam sweeping configuration, “Procedure B”, (compare with step 470 of Figure 4).

For example, the threshold Hl may correspond to the maximum time alignment error that can be handled by the UE without performing a full beam sweep. An example suitable value of Hl is 640T_c (or similar, e.g., 0.5 pis), where T_c corresponds to the basic time unit. Alternatively or additionally, the value of Hl may depend on one or more of the frequency range in which the UE is operating (e.g., FR1, FR2, etc.), the UE mobility status/state (e.g., the UE speed mode), the UE receiver type (e.g., having an advanced receiver which can mitigate interference, or a receiver with reduced capability), the subcarrier spacing, etc.

Generally, any suitable value related to the timing advance command may replace NTAI and NTA2 in the above comparison between parameter values. Optionally, the UE may additionally use the difference between received reference signal power values (Pl and P2), where Pl and P2 are obtained at the first and second time instances (T1 and T2), respectively. The received reference signal power values used may, for example, be RSRP of RS (such as SSB, CSI-RS, etc.) or signal-to-noise ratio (SNR) of the physical downlink shared channel (PDSCH) conveying the timing advance commands.

For example, the UE may perform measurements according to the first adapted reception beam sweeping configuration, “Procedure A”, (compare with step 460 of Figure 4) only when |NTA2 - NTAI|>H1 and |P1 - P2|>H2, where H2 is a predefined or configurable threshold (compare with steps 450 and 451 of Figure 4). Thus, the UE performs measurements according to the first adapted reception beam sweeping configuration when the magnitude of the difference between parameter values NTAI and NTA2 related to the corresponding timing advance commands TAI and TA2 obtained by the UE at first and second time instances T1 and T2 exceeds (or is equal to) the threshold Hl AND the magnitude of the difference between received reference signal power values Pl and P2 obtained at the first and second time instances T1 and T2 exceeds (or is equal to) the threshold H2. Otherwise, when the magnitude of the difference between parameter values NTAI and NTA2 related to the corresponding timing advance commands TAI and TA2 obtained by the UE at first and second time instances T1 and T2 is less than the threshold Hl OR the magnitude of the difference between received reference signal power values Pl and P2 obtained at the first and second time instances T1 and T2 is less than the threshold H2, UE performs measurements according to the second adapted reception beam sweeping configuration, “Procedure B”, (compare with step 470 of Figure 4).

Typically, a timing advance change exceeding a threshold (i.e., a magnitude of a difference between timing advance values exceeding a parameter threshold) may be a reliable (i.e., sufficient) indicator of UE movement or position change, and is therefore interesting to use as a discriminator for adaptation of the reception beam sweeping configuration. More particularly, the timing advance change exceeding a threshold may be used as a sufficient indicator for maintaining or changing to procedure A (comparing with method 400 of Figure 4, this would correspond to the Y-path out of step 450 always leading to step 460).

In some scenarios, a fact that there is no timing advance change exceeding a threshold (i.e., a magnitude of a difference between timing advance values not exceeding a parameter threshold) may be an unreliable (i.e., not sufficient) indicator that the UE is stationary. For example, the UE may move while keeping the same distance to the radio access node. Therefore, there being no timing advance change exceeding a threshold may be complemented by a first received reference signal power condition, according to some embodiments, to determine whether to apply Procedure A or Procedure B (comparing with method 400 of Figure 4, this would correspond to the N-path out of step 450 - instead of directly to step 470 - leading to step 451, which in turn implements a selection between step 460 and step 470).

Generally, Procedure A may be defined as an adapted reception beam sweeping configuration with relatively high amount of reception beam measurements per duration of time and Procedure B may be defined as an adapted reception beam sweeping configuration with relatively low amount of reception beam measurements per duration of time.

Some examples of possible differences (each of which may be applied alone or in combination with one or more of the other differences) between Procedure A and Procedure B include:

The number of reception beam sweeps performed by the UE in Procedure A is larger (e.g., by some margin) than the number of reception beam sweeps performed by the UE in Procedure B.

The UE applies full beam sweeping (i.e., sweeps all its reception beams) or first partial beam sweeping (i.e., sweeps only some of its reception beams) in Procedure A, while applying second partial beam sweeping (i.e., sweeps only some of its reception beams; less than for Procedure A) or no beam sweeping at all in Procedure B.

The number of transmission beams measured during a single reception beam sweep is larger in Procedure A (e.g., all TX beams) than in Procedure B (e.g., only the best transmission beams).

The UE performs beam sweeping at a higher rate in Procedure A than in Procedure B (i.e., the applicable - all or only some - beams are swept more frequently in Procedure A than in Procedure B). In some embodiment, a margin is applied between the rates of Procedures A and B. The beam sweeping rate may, for example, be defined as the number of reception beam sweeps performed per time period. The rate variation may be implemented, for example, by performing beam sweeps every N_AT_SSB, or every M_AT_DRX, or every max (N_AT_SSB, M_AT_DRX) for Procedure A and by performing beam sweeps every N_BT_SSB, or every M_BT_DRX, or every max (N_BT_SSB, M_BT_DRX) for Procedure B, wherein T_SSB denotes the SSB periodicity, T_DRX denotes the discontinuous reception (DRX) cycle, and N_A, N_B, M_A, M_B are integers with N_A < N_B and M_A < M_B.

The total measurement time (e.g., the delay until a beam decision can be made) is longer in Procedure A than in Procedure B.

Using the adapted reception beam sweeping configurations may offer increased opportunities - in terms of number of opportunities and/or length of each opportunity - for the UE to enter a low power mode (e.g., a sleep mode). Thereby, the power consumption of the UE may be decreased by application of some embodiments. The UE may be configured to repeatedly evaluate the applied reception beam sweeping configuration (e.g., check whether|NTA2 - NTAI|>H1). For example, the evaluation may be performed periodically (with a fixed or configurable period), and/or when an activity requires the UE to perform DL measurements, and/or when a timing advance command is received, and/or when a certain time has elapsed since the previous evaluation. In some embodiments, the UE may be configured to request a timing advance update from the radio access node (e.g., if measurements indicate high mobility of the UE) and perform an evaluation when the timing advance update command is received.

In a second example case study (which may be combined with the method 300b of Figure 3B according to some embodiments), a second received reference signal power condition is used to determine to what extent the reception beam sweeping should be adapted (e.g., how much the amount of reception beam measurements performed per time duration should be reduced compared to a default reception beam sweeping configuration).

The received signal power may be expressed via any suitable metric (e.g., one or more of RSRP, RSRQ, SS-RSRP, SS-RSRQ, SINR, RS-SINR, SS-SINR, CSI-RSRP, CSI-RSRQ, and RSSI).

If the received signal power exceeds a power threshold value, the reception beam sweeping configuration may be relaxed according to this example case study.

The second received reference signal power condition may be applied per cell. For example, a UE can apply beam sweeping relaxation (e.g., using Procedure A and/or B) in serving cell and/or neighbor cells with intra-frequency measurements when the received signal power for the corresponding cell exceeds a first power discrimination threshold. Alternatively or additionally, a UE can apply beam sweeping relaxation (e.g., using Procedure A and/or B) in neighbor cells with inter-frequency measurements when the received signal power for the cell exceeds a second power discrimination threshold, which may have the same, or a different, value compared to the first power discrimination threshold. In some embodiments, the method 300b of Figure 3B is performed per cell and the above second received reference signal power condition(s) may be seen as part of step 320b and/or of step 325b. The received signal power for a cell may be an average or cumulative received signal power of multiple best beams (e.g., of the best and/or second best and/or third best beams). Alternatively or additionally, the received signal power for a cell may be an absolute, or relative, signal strength difference between the two or more best beams.

Alternatively or additionally, the second received reference signal power condition may be applied per beam. For example, a UE can apply beam sweeping relaxation for a beam (e.g., decreasing the number of samples taken from the beam) when the received signal power for the beam exceeds a third power discrimination threshold. In some embodiments, the second received reference signal power condition may be used to reduce the amount of reception beam measurements performed per duration of time for the adapted reception beam sweeping configurations (e.g., as applied in step 360b and/or step 370b of Figure 3B).

The first/second/third first power discrimination threshold(s) may be static (e.g., pre-configured by the wireless communication network, or predefined by a RAT standard) or dynamically adjustable (e.g., configured by the wireless communication network via a radio access node, or autonomously configured by the UE).

In some embodiments, instead of a first/second/third first power discrimination threshold, a plurality of threshold values are applied to determine which of a plurality of adapted reception beam sweeping configurations to apply. Letting the number of thresholds increase towards infinity renders embodiments where the mapping between received signal power and adapted reception beam sweeping configurations approaches a continuous function transformation.

The described embodiments and their equivalents may be realized in software or hardware or a combination thereof. The embodiments may be performed by general purpose circuitry. Examples of general purpose circuitry include digital signal processors (DSP), central processing units (CPU), co-processor units, field programmable gate arrays (FPGA) and other programmable hardware. Alternatively or additionally, the embodiments may be performed by specialized circuitry, such as application specific integrated circuits (ASIC). The general purpose circuitry and/or the specialized circuitry may, for example, be associated with or comprised in an apparatus such as a communication device (e.g., a user equipment, UE, or a radio access node).

Embodiments may appear within an electronic apparatus (such as a UE or a radio access node) comprising arrangements, circuitry, and/or logic according to any of the embodiments described herein. Alternatively or additionally, an electronic apparatus (such as a UE or a radio access node) may be configured to perform methods according to any of the embodiments described herein. According to some embodiments, a computer program product comprises a non-transitory computer readable medium such as, for example, a universal serial bus (USB) memory, a plug-in card, an embedded drive, or a read only memory (ROM). Figure 6 illustrates an example computer readable medium in the form of a compact disc (CD) ROM 600. The computer readable medium has stored thereon a computer program comprising program instructions. The computer program is loadable into a data processor (PROC; e.g., a data processing unit) 620, which may, for example, be comprised in a communication device (e.g., a UE or a radio access node) 610. When loaded into the data processor, the computer program may be stored in a memory (MEM) 630 associated with, or comprised in, the data processor. According to some embodiments, the computer program may, when loaded into, and run by, the data processor, cause execution of method steps according to, for example, any of the methods illustrated in Figures 2, 3 A, 3B, and 4, or otherwise described herein. Generally, all terms used herein are to be interpreted according to their ordinary meaning in the relevant technical field, unless a different meaning is clearly given and/or is implied from the context in which it is used.

Reference has been made herein to various embodiments. However, a person skilled in the art would recognize numerous variations to the described embodiments that would still fall within the scope of the claims.

For example, the method embodiments described herein discloses example methods through steps being performed in a certain order. However, it is recognized that these sequences of events may take place in another order without departing from the scope of the claims. Furthermore, some method steps may be performed in parallel even though they have been described as being performed in sequence. Thus, the steps of any methods disclosed herein do not have to be performed in the exact order disclosed, unless a step is explicitly described as following or preceding another step and/or where it is implicit that a step must follow or precede another step. In the same manner, it should be noted that in the description of embodiments, the partition of functional blocks into particular units is by no means intended as limiting. Contrarily, these partitions are merely examples. Functional blocks described herein as one unit may be split into two or more units. Furthermore, functional blocks described herein as being implemented as two or more units may be merged into fewer (e.g. a single) unit.

Any feature of any of the embodiments disclosed herein may be applied to any other embodiment, wherever suitable. Likewise, any advantage of any of the embodiments may apply to any other embodiments, and vice versa.

Hence, it should be understood that the details of the described embodiments are merely examples brought forward for illustrative purposes, and that all variations that fall within the scope of the claims are intended to be embraced therein.

Claims

1. A method of controlling reception beam sweeping by a communication device for beam connection maintenance, the method comprising: repeatedly evaluating (240, 340a, 340b, 440) values of one or more parameter obtained at the communication device, wherein the one or more parameter is associated with channel conditions for the communication device; determining (250, 350a, 350b, 450, 451) whether, for at least one of the one or more parameters, a magnitude of a difference between values of two or more different time instants exceeds a parameter threshold; and in response to determining that the magnitude of the difference between values exceeds the parameter threshold, applying (260, 360a, 370a, 360b, 370b, 460, 470) an adapted reception beam sweeping configuration for the communication device, wherein the adapted reception beam sweeping configuration is obtained by varying an amount of reception beam measurements performed per duration of time.

2. The method of claim 1, wherein the amount of reception beam measurements performed per duration of time for the adapted reception beam sweeping configuration is lower than a default amount of reception beam measurements performed per duration of time for a default reception beam sweeping configuration.

3. The method of any of claims 1 through 2, wherein varying the amount of reception beam measurements performed per duration of time comprises one or more of: increasing or decreasing a total number of reception beam measurements performed during a reception beam sweep; increasing or decreasing a number of reception beams considered per transmission beam; increasing or decreasing a number of transmission beams considered per reception beam; increasing or decreasing a reception beam sweeping rate; and increasing or decreasing, for at least one reception beam, a number of reception beam measurements performed for the reception beam.

4. The method of any of claims 1 through 3, wherein the adapted reception beam sweeping configuration is a first adapted reception beam sweeping configuration (360a, 460), the method further comprising, in response to determining that the magnitude of the difference between values does not exceed the parameter threshold, applying (370a, 470) a second adapted reception beam sweeping configuration.

5. The method of claim 4, wherein the amount of reception beam measurements performed per duration of time for the first adapted reception beam sweeping configuration is higher than the amount of reception beam measurements performed per duration of time for the second adapted reception beam sweeping configuration.

6. The method of any of claims 1 through 5, wherein the one or more parameter comprises a timing advance controlled by timing advance commands of a radio access node.

7. The method of claim 6, wherein determining that the magnitude of the difference between values exceeds the parameter threshold for the timing advance comprises determining (450) that a magnitude of a difference between a first timing advance value resulting from a first timing advance command of a first time instance and a second timing advance value resulting from a second timing advance command of a second time instance exceeds a timing advance threshold.

8. The method of claim 7, wherein the amount of reception beam measurements performed per duration of time is decreased when the magnitude of the difference between the first timing advance value and the second timing advance value is less than the timing advance threshold, and/or wherein the amount of reception beam measurements performed per duration of time is increased when the magnitude of the difference between the first timing advance value and the second timing advance value exceeds the timing advance threshold.

9. The method of any of claims 6 through 8, wherein applying the adapted reception beam sweeping configuration is performed only when (420) a time alignment timer of the communication device is running.

10. The method of any of claims 1 through 9, wherein the one or more parameter comprises a received signal power.

11. The method of claim 10, wherein determining that the magnitude of the difference between values exceeds the parameter threshold for the received signal power comprises determining (350b, 451) that a magnitude of a difference between a first signal power received at a first time instance and a second signal power received at a second, later, time instance exceeds a received signal power threshold. 12. The method of claim 11, further comprising determining (355b) whether the second signal power is higher than the first signal power.

13. The method of claim 12, wherein applying (370b) the adapted reception beam sweeping configuration comprises decreasing the amount of reception beam measurements performed per duration of time when the second signal power is higher than the first signal power, and/or increasing the amount of reception beam measurements performed per duration of time when the first signal power is higher than the second signal power.

14. The method of any of claims 1 through 13 selectively performed (320a, 320b) depending on a physical downlink control channel, PDCCH, monitoring state of the communication device.

15. The method of any of claims 1 through 14 selectively performed (320a, 320b), for one or more cell with intra-frequency reception beam measurements, depending on received signal power value.

16. The method of any of claims 1 through 15 selectively performed (320a, 320b), for one or more neighbor cell with inter-frequency reception beam measurements, depending on received signal power value.

17. The method of any of claims 1 through 16 selectively performed (320a, 320b) depending on a mobility status of the communication device.

18. The method of any of claims 1 through 17 selectively performed (320a, 320b) depending on a user equipment, UE, power class used for operation by the communication device.

19. A computer program product comprising a non-transitory computer readable medium (600), having thereon a computer program comprising program instructions, the computer program being loadable into a data processing unit and configured to cause execution of the method according to any of claims 1 through 18 when the computer program is run by the data processing unit. 0. An apparatus for controlling reception beam sweeping by a communication device for beam connection maintenance, the apparatus comprising controlling circuitry (520) configured to cause: repeated evaluation of values of one or more parameter obtained at the communication device, wherein the one or more parameter is associated with channel conditions for the communication device; determination of whether, for at least one of the one or more parameters, a magnitude of a difference between values of two or more different time instants exceeds a parameter threshold; and in response to determination that the magnitude of the difference between values exceeds the parameter threshold, application of an adapted reception beam sweeping configuration for the communication device, wherein the adapted reception beam sweeping configuration is obtained by varying an amount of reception beam measurements performed per duration of time. e apparatus of claim 20, wherein the amount of reception beam measurements performed per duration of time for the adapted reception beam sweeping configuration is lower than a default amount of reception beam measurements performed per duration of time for a default reception beam sweeping configuration. e apparatus of any of claims 20 through 21, wherein the controlling circuitry is configured to cause variation of the amount of reception beam measurements performed per duration of time by causing one or more of: increasing or decreasing a total number of reception beam measurements performed during a reception beam sweep; increasing or decreasing a number of reception beams considered per transmission beam; increasing or decreasing a number of transmission beams considered per reception beam; increasing or decreasing a reception beam sweeping rate; and increasing or decreasing, for at least one reception beam, a number of reception beam measurements performed for the reception beam. e apparatus of any of claims 20 through 22, wherein the adapted reception beam sweeping configuration is a first adapted reception beam sweeping configuration, and wherein the controlling circuitry is further configured to cause, in response to determination that the magnitude of the difference between values does not exceed the parameter threshold, application of a second adapted reception beam sweeping configuration. e apparatus of claim 23, wherein the amount of reception beam measurements performed per duration of time for the first adapted reception beam sweeping configuration is higher than the amount of reception beam measurements performed per duration of time for the second adapted reception beam sweeping configuration.

25. The apparatus of any of claims 20 through 24, wherein the one or more parameter comprises a timing advance controlled by timing advance commands of a radio access node.

26. The apparatus of claim 25, wherein the controlling circuitry is configured to cause determination that the magnitude of the difference between values exceeds the parameter threshold for the timing advance by causing determination that a magnitude of a difference between a first timing advance value resulting from a first timing advance command of a first time instance and a second timing advance value resulting from a second timing advance command of a second time instance exceeds a timing advance threshold.

27. The apparatus of claim 26, wherein the amount of reception beam measurements performed per duration of time is decreased when the magnitude of the difference between the first timing advance value and the second timing advance value is less than the timing advance threshold, and/or wherein the amount of reception beam measurements performed per duration of time is increased when the magnitude of the difference between the first timing advance value and the second timing advance value exceeds the timing advance threshold.

28. The apparatus of any of claims 25 through 27, wherein the controlling circuitry is configured to cause application of the adapted reception beam sweeping configuration only when a time alignment timer of the communication device is running.

29. The apparatus of any of claims 20 through 28, wherein the one or more parameter comprises a received signal power.

30. The apparatus of claim 29, wherein the controlling circuitry is configured to cause determination that the magnitude of the difference between values exceeds the parameter threshold for the received signal power by causing determination that a magnitude of a difference between a first signal power received at a first time instance and a second signal power received at a second, later, time instance exceeds a received signal power threshold.

31. The apparatus of claim 30, wherein the controlling circuitry is further configured to cause determination of whether the second signal power is higher than the first signal power.

32. The apparatus of claim 31, wherein the controlling circuitry is configured to cause application of the adapted reception beam sweeping configuration by causing decrease of the amount of reception beam measurements performed per duration of time in response to the second signal power being higher than the first signal power, and/or causing increase of the amount of reception beam measurements performed per duration of time in response to the first signal power being higher than the second signal power.

33. The apparatus of any of claims 20 through 32, wherein the controlling circuitry is configured to cause selective application of adaptive reception beam sweeping depending on a physical downlink control channel, PDCCH, monitoring state of the communication device.

34. The apparatus of any of claims 20 through 33, wherein the controlling circuitry is configured to cause selective application of adaptive reception beam sweeping, for one or more cell with intra-frequency reception beam measurements, depending on received signal power value.

35. The apparatus of any of claims 20 through 34, wherein the controlling circuitry is configured to cause selective application of adaptive reception beam sweeping, for one or more neighbor cell with inter-frequency reception beam measurements, depending on received signal power value.

36. The apparatus of any of claims 20 through 35, wherein the controlling circuitry is configured to cause selective application of adaptive reception beam sweeping depending on a mobility status of the communication device.

37. The apparatus of any of claims 20 through 36, wherein the controlling circuitry is configured to cause selective application of adaptive reception beam sweeping depending on a user equipment, UE, power class used for operation by the communication device.

38. A user equipment, UE, comprising the apparatus of any of claims 20 through 37.

39. A radio access node comprising the apparatus of any of claims 20 through 37.