Joint communication and sensing

Abstract

There is disclosed a method of operating a radio node in a wireless communication net- work, the radio node being adapted for wireless communication, and being adapted for multi-static sensing and / or radar operation, the method comprising selecting a second group of radio nodes for transmission of sensing signalling from a first group of radio 2555 nodes based on an error evaluation of radio nodes of the first group of radio nodes, the first group comprising the second group The disclosure also pertains to related devices and methods.

Description

[0001] Joint Communication and Sensing

[0002] Technical field

[0003] This disclosure pertains to wireless communication and radar technology, in particular for high frequencies.

[0004] Background

[0005] For future wireless communication systems, combining wireless communication and sens- 5 ing (radar) is discussed, in particular using the same spectrum and / or hardware for both. This is sometimes referred to as Joint Communication and Sensing (JCAS), or Integrated Sensing and Communication (IS AC); JCAS and IS AC may be used synonymously. Combining these functionalities brings a number of challenges.

[0006] Summary 10

[0007] It is an object of this disclosure to provide approaches of handling JCAS, in particular regarding multiplexing of communication signalling and sensing signalling. The approaches described may be utilised for one or more different frequencies ranges. For example, they may be implemented for frequency ranges (e.g., carrier bandwidth and / or system bandwidth) for sensing signalling and / or communication signalling of 1 GHz or more, 2GHz 15 or more, 5 GHz or more, or 6 GHz or more, or 10 GHz or more, and / or for millimetre wave communication, in particular for radio carrier frequencies around and / or above 52.6 GHz, which may be considered high radio frequencies (high frequency) and / or millimetre waves. The carrier frequency / ies may be between 52.6 and 140 GHz, e.g. with a lower border between 52.6, 55, 60, 71 GHz and / or a higher border between 71, 72, 90, 20

[0008] 114, 140 GHz or higher, in particular between 55 and 90 GHz, or between 60 and 72 GHz; however, higher frequencies may be considered, in particular frequency of 71 GHz or 72GHz or above, and / or 100 GHz or above, and / or 140 GHz or above. The carrier frequency may in particular refer to a centre frequency or maximum frequency of the carrier. The radio nodes and / or network described herein may operate in wide-band, e.g. 25 with a carrier bandwidth (or bandwidth or carrier aggregation) of 400MHz or more, in particular 1 GHz or more, or 2 GHz or more, or even larger, e.g. 6 GHz or more, or 8 GHz or more; the scheduled or allocated bandwidth may be the carrier bandwidth, or be smaller, e.g. depending on channel and / or procedure. In some cases, operation may be based on an OFDM wave- form or a SC-FDM wave- form (e.g., downlink and / or 30 uplink), in particular a FDF-SC-FDM-based wave-form. However, operation based on a single carrier wave-form, e.g. SC-FDE (which may be pulse-shaped or Frequency Domain Filtered, e.g. based on modulation scheme and / or MGS), may be considered for downlink and / or uplink. In general, different wave-forms may be used for different communication directions. Communicating using or utilising a carrier and / or beam may correspond to 35

[0009] P111608W001 1 / 77 operating using or utilising the carrier and / or beam, and / or may comprise transmitting on the carrier and / or beam and / or receiving on the carrier and / or beam. Operation may be based on and / or associated to a numerology, which may indicate a sub-carrier spacing and / or duration of an allocation unit and / or an equivalent thereof, e.g., in comparison to an OFDM based system. A sub-carrier spacing or equivalent frequency interval may 40 for example correspond to 960 kHz, or 1920 kHz, e.g. representing the bandwidth of a subcarrier or equivalent.

[0010] The approaches are particularly advantageously implemented in a future 6th Generation (6G) telecommunication network or 6G radio access technology or network (RAT / RAN), in particular according to 3GPP (3rd Generation Partnership Project, a standardisation 45 organization). A suitable RAN may in particular be a RAN according to NR, for example release 18 or later, or LTE Evolution. However, the approaches may also be used with other RAT, for example future 5.5G systems or IEEE based systems.

[0011] There is disclosed a method of operating a (sensing) radio node in a wireless communication network. The (sensing) radio node is adapted for wireless communication, and is 50 adapted for multi-static sensing and / or radar operation. The method comprises selecting a second group of radio nodes for transmission of sensing signalling from a first group of radio nodes based on an error evaluation of radio nodes of the first group of radio nodes, the first group (of radio nodes) comprising the second group (of radio nodes). The method may comprise, and / or selecting may comprise, performing sensing operation, e.g., based 55 on the selecting and / or the second group.

[0012] Moreover, a (sensing) radio node for a wireless communication network is proposed. The (sensing) radio node is adapted for wireless communication, and is adapted for multistatic sensing and / or radar operation. The (sensing) radio node is adapted for selecting a second group of radio nodes for transmission of sensing signalling from a first group 60 of radio nodes based on an error evaluation of radio nodes of the first group of radio nodes, the first group (of radio nodes) comprising the second group (of radio nodes).

[0013] The (sensing) radio node may be adapted for, and / or selecting may comprise, performing sensing operation, e.g., based on the selecting and / or the second group.

[0014] The (sensing) radio node may be a network node and / or base station and / or sensing 65 controlling node. The (sensing) radio node being adapted for multi-static sensing may comprise and / or refer to the (sensing) radio node being adapted for receiving and / or processing and / or evaluating sensing signalling from one or more other nodes, and / or for scheduling one or more other nodes for transmitting sensing signalling, e.g., first sensing signalling and / or second sensing signalling. Multi-static sensing may pertain to 70 sensing utilising two or more radio nodes (including the sensing radio node); bi-static

[0015] P111608W001 2 / 77 sensing may be considered a form of multi-static sensing. Multi-static sensing may refer to sensing in which at least some sensing signalling is received by a radio node that has not transmitted this sensing signalling. Processing and / or evaluating sensing signalling may comprise demodulating and / or determining one or more peaks (e.g., Doppler and / or 75 path-delay) and / or a radar cube, and / or combining sensing information from one or more sensing signallings and / or transmitters and / or targets, and / or sensor fusion and / or object mapping and / or tracking. Performing sensing operation may comprise object detection and / or tracking. An object to be detected and / or sensed and / or tracked may be considered a target or intended target. Performing sensing or sensing operation may 80 comprise sensing a sensing area, e.g., for object detection and / or tracking. The sensing or sensing operation may be multi-static. Performing sensing or sensing operation based on the selecting and / or the second group may comprise receiving and / or monitoring for sensing signalling (e.g., second sensing signalling) from one or more or all of the radio nodes of the second group of radio nodes, and / or scheduling one or more or all 85 of the radio nodes of the second group of radio nodes for transmission of (e.g., second) sensing signalling. Scheduling may comprise transmitting scheduling information and / or instructions to one or more radio nodes and / or triggering the one or more radio nodes to transmit sensing signalling; scheduling information may be configured with higher layer signalling and / or provided with physical layer signalling. Scheduling information for 90 sensing signalling may indicate one or more transmission parameters for sensing signalling, e.g., signalling sequence (e.g., which sequence to use for reference signalling) and / or timing and / or frequency and / or periodicity, and / or time and / or frequency resources, and / or beam / s for transmission, and / or beam sweeping pattern.

[0016] Selecting may be based on multi-static operation and / or sensing. Radio nodes of the 95 first group and / or the second group may be available, and / or adapted, for transmission of sensing signalling, e.g., for multi-static sensing operation. Selecting may comprise determining the second group based on the first group, e.g., such that radio nodes from the first group are selected to be part of the second group. Selecting may be based on first sensing signalling transmitted, e.g., by radio nodes of the first group. The first sensing 100 signalling may not necessarily be intended for a target, but may allow evaluating for future sensing and thus be considered sensing signalling.

[0017] Performing sensing operation may be based on selecting, e.g., such that sensing operation may be performed based on sensing signalling (e.g., second sensing signalling) transmitted by radio nodes of the second group. The size of the second group may in general be smaller 105 than, or at most equal to, the size of the first group (size may correspond to the number of radio nodes and / or potential transmission instances or sources in the group).

[0018] P111608W001 3 / 77 Error evaluation may pertain to determining and / or estimating and / or predicting one or more error parameters, and / or one or more accuracy parameters. Error and / or accuracy parameters may pertain to an error covariance matrix, and / or may represent charac- 110 teristic / s thereof, and / or may be determinable from, and / or representative of, an error covariance matrix.

[0019] Selecting may be performed repeatedly, e.g., for each target and / or sensing area. Selecting may be performed periodically or semi-periodically, e.g., based on a pre-determined periodicity and / or based on a target movement and / or speed or velocity. Alternatively, or 115 additionally, selecting may be event-triggered, e.g., based on available radio nodes and / or target behaviour. In some cases, changes to available radio nodes (e.g., hand-over to other cell or radio node), and / or movement and / or condition changes (e.g., moving behind an obstacle) may trigger a new selecting. Selecting may comprise, and / or be based on, updating the first group, e.g., adding and / or removing one or more radio nodes from the 120 group, e.g., based on availability and / or presence and / or signal strength or quality, e.g., as determined based on communication operation. Communication operation may comprise determining position and / or signal strength and / or quality, e.g., based on communication signalling. The second group may comprise one or more radio nodes; the first group may comprise at least as many, or more, radio nodes than the second group. 125

[0020] Approaches described herein may facilitate efficient use of resources in multi-static sensing, e.g., such that unnecessary use of radio nodes may be limited.

[0021] Error evaluation may be specific to a target of multi-static sensing, and / or to a sensing area of multi-static sensing. Different error evaluations may pertain to different targets and / or areas. In general, there may be different first groups and / or different second group 130 associated to different targets and / or sensing area. It may be considered that performing sensing operation may be based on different second groups for different targets and / or different sensing areas.

[0022] Error evaluation may be based on one or more Dilution of Precision, DOP, parameters, and / or may comprise optimising DOP (e.g., minimising or reducing one or more DOP 135 parameters). Error evaluation may comprise and / or be based on estimating and / or determining an effect of sensing signalling from one or more radio nodes of the first group on one or more DOP parameters, e.g., for a specific target or group of targets or sensing are. Error evaluation may be based on and / or comprise determining whether a threshold value of improvement (e.g., DOP reduction and / or accuracy increase) is achieved or provided 140 (or expected to be) for one or more radio nodes of the first group. Error evaluation may in general comprise selecting one or more radio nodes of the first group to be part of the second group.

[0023] P111608W001 4 / 77 It may be considered that error evaluation may be based on, and / or may comprise, error evaluation for radio nodes of the first group of radio nodes. The first group of radio 145 nodes may comprise radio nodes available for multi-static sensing, e.g., based on capability and / or location and / or line-of-sight considerations and / or speed / movement or similar criteria, and / or may be pre-selected from such radio nodes and / or based on one or more of such criteria. Error evaluation of or for a radio node may be based on (sensing) signalling from that UE, and / or information determined based on communication operation, e.g., 150 position and / or signal strength and / or signal quality, and / or based one or more parameters known that might impact the sensing quality (e.g., error or accuracy), for example direction and / or speed and / or velocity and / or location, e.g., as absolute values, or relative to a target or object (e.g., obstacle), and / or pertaining to the radio node evaluated and / or the target. 155

[0024] The first group of radio nodes may be variable over time, e.g., in terms of number of, and / or which, radio nodes are in the group. Changes and / or variability of the first group (e.g., performed by the sensing radio node) may for example be based on movement and / or position changes and / or communication handovers. Radio nodes may be added or removed from the first group, e.g., over a given time interval, which may be different 160 from (e.g., larger than) a time interval over which the second group of radio nodes may be variable, or may be the same. Changes to, and / or updating, the first group may be event- triggered and / or periodic and / or semi-periodic. Dynamic behaviour of communication and / or radio nodes may be accounted for.

[0025] In some variants, the second group of radio nodes may be variable over time, e.g., in 165 terms of number of, and / or which, radio nodes are in the group. This may in particular account for short-term changes in sensing conditions and / or communication conditions. Changing the second group and / or updating the second group may be periodic and / or semi-periodic, and / or event-triggered; changing and / or updating the second group may be based on a changed first group, or an unchanged first group, and / or may be considered 170 an instance of selecting the second group. Thus, different second groups may be used for the same target or sensing area over time, accommodating dynamic behaviour of the target and / or radio nodes and / or environment.

[0026] The first group of radio nodes may be a first group of user equipments, UEs, and / or may comprise one or more UEs. These may be connected to the (sensing) radio node, e.g., be 175 in a RRC connected or similar state, and / or may camp on a cell provided by the sensing radio node. The sensing radio node may be a network node or gNB or base station or similar, and / or may be adapted to control the communication operation and / or sensing operation of the radio node / s of the first group.

[0027] P111608W001 5 / 77 Error evaluation may be based on first sensing signalling transmitted by radio nodes of 180 the first group of radio nodes. The first sensing signalling may be scheduled by the sensing radio node. This may allow reliable signalling and / or error evaluation.

[0028] Selecting may be based on one or more additional criteria or factors. This may allow optimised and / or more refined selecting, e.g., based on task requirements.

[0029] In general, selecting may comprise cycling through the first group of radio nodes and / or 185 the second group, e.g., performing error evaluation for each radio node in the first group, and / or for each radio node of the second group (e.g., when performing a second or further selecting). This may include scheduling sensing signalling to be transmitted by the evaluated radio node, and / or receiving sensing signalling (e.g., first sensing signalling) from the evaluated radio node. It may be considered that after a first selecting, second sensing 190 signalling may be utilised a first sensing signalling for further selecting.

[0030] Sensing and / or radar operation may be used interchangeably. Sensing operation may be performed in a sensing mode. Communication may be performed in a communication mode. Different antenna arrangements and / or different nodes may operate in different modes; in some cases, different antenna arrangements of the same radio node may operate 195 in different modes, e.g. using frequency domain multiplexing (e.g., in addition to and / or overlaid on time domain multiplexing). Sensing operation may comprise transmitting and / or receiving sensing signalling. Sensing signalling may be signalling intended to be bounced of one more targets, e.g. to determine a presence, and / or a location, and / or velocity, and / or speed of the target / s from the reflected signalling. Sensing operation 200 may be mono-static, or in some cases bi-static or multi-static.

[0031] It may be considered that the communication signalling is based on a multi-carrier waveform, e.g. an OFDM wave-form, for example a DFT-s-OFDM based wave-form, and / or that the communication signalling is based on a waveform with cyclic appendix. A cyclic appendix may generally be a cyclic prefix, or a cyclic suffix. The appendix may represent 205 a repetition of a part of signalling carried by a symbol at its start (suffix) or end (prefix), which may be appended at the opposite of the symbol (end or start); e.g. a cyclic prefix may be considered a repetition of the signalling at the end of the symbol it pertains to.

[0032] A cyclic appendix may be associated to a specific symbol, it may have a duration shorter than the symbol duration, e.g. less than 1 / 4 of the symbol duration, or less than 1 / 6. 210

[0033] The radio node may operate in TDD mode, e.g. switching between DL periods and UL periods. A DL period may be a period in which the radio node operates using DL transmissions, an UL period may be a period in which the radio node operates using UL transmissions (e.g., a network node may transmit during DL, and receive during UL, and

[0034] P111608W001 6 / 77 vice versa for a wireless device). It may be considered that there is a TDD guard period 215 between DL and UL periods and / or between UL and DL periods, which may comprise a number of symbol time intervals, e.g. 10 or more symbols, or 12 or more symbols; there may be the same duration for guard periods for DL / UL and UL / DL, or different ones.

[0035] The guard period may allow switching circuitry between the different communication directions and / or handling of interference (in particular considering that DL signalling tends 220 to much more powerful than (received) UL signalling). Time domain multiplexing of sensing signalling and communication signalling may refer to and / or include and / or comprise and / or represent switching between communication mode and sensing mode such that at different times, different modes are used at least for a part of the circuitry and / or antenna arrangements and / or signalling associated to the radio node. An antenna arrangement 225 may comprise one or more antenna elements and / or sub-arrays and / or panels; different antenna arrangements may comprise different antenna elements and / or sub-arrays and / or panels. Different antenna arrangements and / or panels and / or sub-arrays and / or elements may be adapted to be controlled or controllable separately from each other. There may be the same number of DL and UL periods and / or the same duration associated to DL 230 and UL (at least over a certain time interval, e.g. alternating such that one DL period is followed by one UL period, or vice versa, or different numbers or durations, e.g. (roughly) 3:1 (e.g., 3 DL periods followed by a TDD guard period and 1 UL period), or (roughly) 2:1, or even (roughly) 1:2 or 1:NU with NU 3 or larger, for UL heavy scenarios. UL period durations may be the same as DL period durations, or different. The distribution and / or 235 duration of DL and UL periods may be referred to as TDD pattern; the TDD pattern may be dynamically controllable (e.g., with DCI signalling), and / or configured or configurable, e.g. with higher layer signalling like RRC signalling or RLC signalling, and / or may be semi-statically configurable or configured. The TDD pattern may describe the smallest time domain distribution of DL period / s and / or UL period / s and / or TDD guard period / s 240 repeated over time, e.g. in one or more frames and / or subframes and / or slots and / or a time duration covering multiple repetitions of the TDD pattern. It may be considered that operating in sensing mode may comprise both transmission and reception by the same radio node, independent of the TDD period associated to a communication mode.

[0036] It may be considered that a sensing mode and / or sensing interval may be inserted and / or 245 embedded and / or multiplexed into a time period nominally associated to DL and / or UL and / or a TDD guard period, in particular a DL / UL guard period.

[0037] The sensing signalling and communication signalling may be transmitted by the same transmitting node, e.g. the radio node, or by different nodes. In particular, it may be considered that the radio node transmits both communication signalling and sensing 250 signalling, and may additionally monitor for and / or receive a reflection of the sensing

[0038] P111608W001 7 / 77 signalling, e.g. in a mono-static scenario. In some cases, the radio node may receive the communication signalling and the sensing signalling, and / or may additionally transmit the sensing signalling, e.g. in a mono-static scenario. In some cases, the radio may transmit the communication signalling and receive (and / or monitor for) the sensing signalling, and 255 additionally may transmit the sensing signalling, or vice versa. It should be considered that the receiving sensing signalling may comprise, and / or be based on monitoring for the sensing signalling, e.g. utilising one or more reception beams and / or beam sweeping. Received or monitored for sensing signalling may represent reflected and / or diffracted sensing signalling, e.g. after impacting a target object and / or obstacle. Operation using 260 sensing signalling and communication signalling may pertain to a specific time period, e.g. a joint operation interval, in which both communication and sensing is performed. There may be operational states of the radio node focussing on one type of operation, e.g. only communicating or sensing. Sensing signalling being frequency multiplexed (also known as being frequency domain multiplexed, or frequency duplexed) with communica- 265 tion signalling may refer to the sensing signalling having a different location in frequency domain than the communication signalling, e.g. in non-overlapping parts of the spectrum (non-overlapping bandwidths). In particular, sensing signalling may occupy a first frequency bandwidth, and the communication signalling may occupy a second frequency bandwidth, wherein the first and second frequency bandwidths may be non-overlapping 270 and / or disjunct and / or separated in frequency domain.

[0039] The radio node may for example be a wireless device or user equipment or terminal, or a network node or signalling radio node or base station. Thus, sensing functionality may be provided by common participants of a wireless communication network.

[0040] It may be considered that the radio node is adapted for utilising a number NP of an- 275 tenna sub- arrays and / or panels, wherein NP may be an integer number of 4 or larger. An antenna sub-array may comprise a plurality of antenna elements, e.g. 4 or more, or 10 or more, or 50 or more, or 100 or more. An antenna sub-array, and / or the antenna elements associated thereto and / or comprised therein, may be associated and / or connected or connectable to one and / or the same antenna circuitry, and / or be jointly controllable 280 for analog and / or digital beam-forming, and / or be operable for joint transmission or reception. A panel may comprise a support structure, e.g. plastics and / or metallic material and / or wood, supporting one or more antenna sub-arrays, which additionally may support additional circuitry like antenna circuitry and / or interface circuitry. Each antenna sub-array may be associated for one communication direction (e.g., reception or transmis- 285 sion) and / or one functionality, e.g. sensing or communication. It may be considered that antenna elements of an antenna sub-array share the same polarisation, e.g. horizontal or vertical. In some cases, NP may be an even number, wherein it may be considered

[0041] P111608W001 8 / 77 that NP / 2 antenna sub-arrays (and / or their antenna elements) may be associated to a first polarisation (e.g., horizontal or vertical or left-circular or right-circular, or any other 290 suitable polarisation) and the other NP / 2 antenna sub- arrays are associated to a second polarisation, which may be orthogonal to the first polarisation. For example, the first polarisation may be horizontal with the second polarisation being vertical, or the first polarisation may be left-circular and the second polarisation may be right-circular. This allows multiple beams to be operated, with good flexibility and / or large signalling capac- 295 ity. In general, an antenna arrangement associated to a radio node may comprise one or more antenna sub-arrays, in particular an even number of antenna sub-arrays. In general, at different times, different antenna sub-arrays and / or panels may be used for different functions, e.g. transmission or reception, and / or sensing or communication. The polarisation of an antenna element may be associated to a specific operation direction, e.g. for 300 transmission or reception. Depending on signalling direction (transmission or reception), polarisation may be different. For example, an antenna sub-array may be associated to a first polarisation for transmission, and a second polarisation for reception, or vice versa.

[0042] This may be achieved, for example, by providing crossed linear antenna elements for the sub-arrays, with associated connections / circuitry according to polarisation. 305

[0043] In particular, it may be considered that the sensing signalling is transmitted and / or received, e.g. by the radio node, utilising a first set of antenna elements and / or antenna subarrays and / or antenna panels, and the communication signalling is transmitted and / or received, e.g., by the radio node, utilising a second set of antenna elements and / or antenna sub-arrays and / or antenna panels. The first set may comprise different sub-arrays 310 and / or antenna elements and / or antenna panels than the second set. The first set may comprise one or more antenna sub-arrays and / or panels, e.g. NC sub-arrays and / or panels, in particular an even number. It may be considered that the second set may comprise one or more antenna sub-arrays and / or panels, e.g., NS sub-arrays, in particular an even number. It may be considered that NC+NS=NP. In some cases, the NC and / or NS sub- 315 arrays and / or panels may comprise equal number of antenna sub-arrays and / or panels associated to first and second polarisations (in general, an antenna sub-array may be considered associated to a polarisation if all its antenna elements are associated to the same polarisation). It may be considered that different antenna sub-arrays are used for transmitting sensing signalling and receiving signalling, wherein the same polarisation 320 may be associated to transmitting and receiving of sensing signalling.

[0044] It may be considered that the sensing signalling and the communication signalling are transmitted and / or received in an operation time interval, for example a slot, or an integer number N of symbol time intervals or allocation units or block symbols. The operation time interval may correspond to 1 ms or less, or 0.5 ms or less, or .1 ms or less, and / or N 325

[0045] P111608W001 9 / 77 may be 1000 or less, or 300 or less, or 200 or less, or 100 or less, or 20 or less. Thus, the radio node may operate both signalling types in short timescales. Within the operation time interval, the sensing signalling and communication signalling may be operated time multiplexed, or simultaneously, or both (in different sub- intervals).

[0046] In some variants, the sensing signalling and the communication signalling may be trans- 330 mitted and / or received at least partly, or fully, overlapping in time, e.g. in an operation time interval, or one or more sub-intervals thereof. Partly overlapping in time may refer to part of the sensing signalling not overlapping with the communication signalling, fully overlapping may refer to all of the sensing signalling overlapping with communication signalling (in time domain, in particular within the operation time interval and / or one or 335 more sub-intervals thereof).

[0047] In particular, the sensing signalling may in general be transmitted in a sensing time interval, and a reflection of the sensing signalling may be monitored for (and / or received) in a monitoring time interval, wherein the sensing time interval and the monitoring time interval may at least partly, or fully, overlap in time. The sensing time interval and / or 340 the monitoring time interval may be part of an operation time interval, e.g. comprised therein, for example as sub-intervals, or covering the operation time interval. Thus, short timescale joint operation is facilitated.

[0048] It may be considered that a first antenna sub-array and / or antenna panel may be used for transmitting sensing signalling, a second antenna sub-array and / or antenna panel may be 345 used for monitoring and / or receiving a reflection of the sensing signalling. Two or more antenna sub- arrays and / or panels may be used for communicating utilising communication signalling., e.g. during the operation time interval. The first and second sub-array and / or panel may be of different polarisation. In particular for large NP (e.g., 8 or larger), this may facilitate sensing operation with comparatively low impact on communication 350 operation.

[0049] In general, sensing signalling and communication signalling occupy the same frequency spectrum, e.g. the same carrier. Frequency multiplexing may generally refer to different locations of the frequency spectrum being assigned to sensing signalling and communication signalling, e.g. different parts of the carrier bandwidth; additionally, different band- 355 widths may be assigned to sensing signalling and communication signalling. Spectrum re-use thusly may be provided. This may refer to operation time interval / s.

[0050] It may be considered that the sensing signalling may occupy a bandwidth (first frequency bandwidth, or first bandwidth) of 350 MHz or less, or 300 MHz or less, and / or 10% or less of a carrier or system bandwidth, or 5% or less of a carrier or system bandwidth, 360

[0051] P111608W001 10 / 77 and / or 10% or less of the bandwidth (second frequency bandwidth, or second bandwidth) used for communication signalling, and / or 7% or less of the bandwidth used for communication signalling. This may refer to operation time interval / s; outside of such, different bandwidth sizes may be used, e.g. if only communication signalling is used for a longer time (e.g., 5 or more times the operation time interval duration, or 10 or 20 or 50 or more 365 times the operation time interval duration), the full carrier / system bandwidth may be applied for communication signalling. Thus, bandwidth limitation may be ameliorated.

[0052] In some variants, sensing signalling may occupy a first frequency bandwidth (or first bandwidth), and the communication signalling may occupy a second frequency bandwidth (second bandwidth), wherein further a frequency gap may exist, or be, or be located, 370 between the first frequency bandwidth and the second frequency bandwidth. The second frequency bandwidth may be larger in size than the first frequency bandwidth, e.g. it may be SM times the size, wherein SM may be 3 or more, or 5 or more, or 10 or more, or 15 or more. The gap may correspond to a bandwidth smaller than the second frequency bandwidth, and / or may be smaller than the first frequency bandwidth. The gap may 375 correspond to a guard bandwidth, e.g. limiting interference between the first and second frequency bandwidths.

[0053] In general, the communication signalling may be based on an OFDM wave-form, for example a DFT-s-OFDM based wave-form. This may facilitated reliable communication with high capacity. 380

[0054] Approaches described herein facilitate using hardware of a communication radio node for radar or sensing, with limited overhead or loss of efficiency.

[0055] Sensing signalling may generally be represented by reference signalling. Sensing signalling of different types may differ in terms of numerology and / or wave-form and / or modulation symbol sequence and / or sequence root and / or duration and / or frequency bandwidth 385 and / or density (e.g., in time domain and / or frequency domain) and / or code and / or timing, in particular regarding periodicity) and / or beam shape or beam size.

[0056] The communication signalling and / or sensing signalling may be based on an OFDM waveform, e.g. OFDM and / or SC-FDM. Transmitting and / or receiving sensing signalling may be considered operating utilising sensing signalling. It may be considered that operat- 390 ing utilising communication signalling, and / or communicating utilising communication signalling, may comprise transmitting the communication signalling and / or receiving the communication signalling. Depending on whether the radio node is adapted for full- duplex operation or not, operating utilising sensing signalling may comprise operating in the same direction (e.g., both operations comprise or consists of transmitting, or both 395

[0057] P111608W001 11 / 77 comprise or consist of receiving), or in different directions (for either or both operations, or between operations and / or for one operation). Thus, different use cases and types of setup (mono-static or multi-static) may be considered.

[0058] In some cases, operating utilising sensing signalling may comprise transmitting the sensing signalling and / or receiving the sensing signalling. In general, receiving sensing signalling 400 may comprise receiving reflections of the sensing signalling; the reflections may be shifted in time relative to the transmitting signalling (due to propagation delay); the shift in time may two symbol time intervals or less, or one symbol time interval or less, or the duration of a cyclic prefix or less. The range of the sensing signalling may be configured accordingly. In general, operating utilising sensing signalling may comprise performing 405 sensing and / or determining the presence (or absence) of an object and / or determining one or more properties of one or more objects (sensing targets).

[0059] It may be considered that the communication signalling is based on an OFDM waveform, e.g. OFDM, or DFT-s-OFDM, or pulse-shaped DFT-s-OFDM. Such a wave-form is particularly suitable for wireless communication at high frequencies and / or with high 410 communication loads. In some cases, the sensing signalling may be based on an OFDM wave-form, e.g. OFDM, or DFT-s-OFDM, or pulse-shaped DFT-s-OFDM, or an OFTS based wave-form. The sensing signalling wave-form may be based on the same wave-form as the communication signalling, which allows easy reuse of configurations and circuitries.

[0060] In some cases, it may be based on a different wave-form, allowing flexibility, e.g. for 415 different use cases and functionalities.

[0061] The radio node may be a wireless device or user equipment or terminal. Alternatively, it may be a network node or signalling radio node. A radio node adapted for wireless communication may be a radio node adapted for transmitting and / or receiving communication signalling, and / or for operating with signalling in conformance with a commu- 420 nication standard, e.g. according to a 3GPP standard, and / or adapted for communicating utilising control signalling in conformance with a standard (not necessarily data signalling). A radio node adapted for operating with signalling in conformance with a communication standard may be adapted for utilising signalling and / or waveforms according to the standard, and / or circuitry capable of producing such waveforms and / or 425 signalling. Communication signalling may be. and / or comprise, data signalling and / or control signalling and / or reference signalling, e.g. according to a wireless communication standard like a 3GPP standard or IEEE standard. A radio node adapted for sensing operation and / or radar operation may be adapted for, and / or be configured or configurable, for transmitting and / or receiving signalling for sensing or radar functionality, in 430 particular according to a configuration for sensing and / or processing signalling. The radio

[0062] P111608W001 12 / 77 node may share circuitry like processing circuitry and / or radio circuitry and / or antenna circuitry and / or antenna elements and / or sub-arrays between communication signalling and sensing operation and / or sensing signalling. The sensing operation may be monostatic and / or multi-static. Sensing signalling may be reference signalling, and / or may 435 be communication signalling and / or signalling dedicated for sensing. Sensing signalling may have different types of signalling, e.g. based on, or associated to use and / or object and / or sensing function (e.g., which parameters of an object are to be determined). Multiplexing communication signalling and sensing signalling in a multiplexing time interval may correspond to the communication signalling and the sensing signalling being 440 transmitted in the multiplexing time interval, e.g. by the same node or different nodes. Operating utilising communication signalling may comprise transmitting and / or receiving communication signalling. Operating utilising sensing signalling may comprise transmitting and / or receiving sensing signalling. A radio node may be adapted for mono-static operation. In this case, it may be adapted for full-duplex operation, transmitting and 445 receiving in fully or at least partially overlapping time intervals (e.g., corresponding to, and / or at least partially overlapping with, the multiplexing time interval), such that it may receive reflected sensing signalling it transmitted itself (due to the large speed of radio waves, the reflected sensing signalling will often be received while the radio node still transmits sensing signalling). The radio circuitry and / or processing circuitry and / or 450 antenna circuitry of a radio node may be adapted both for handling communication signalling and sensing signalling. The radio node may be adapted for full-duplex operation, and / or half-duplex operation. Full duplex may refer to transmitting and receiving at the same time, e.g. using the same or different circuitries, and / or using different antenna sub-arrays or separately operable antenna sub-arrays or antenna elements. 455

[0063] The sensing signalling may be beam-formed. The communication signalling may be beam- formed. Different beams, in particular narrower beams, may be used for the sensing signalling than the communication signalling. In some cases, the beam shapes of sensing signalling may be different for different occurrences and / or signalling types and / or functionalities of sensing signalling. Beam-switching may be performed when switching from 460 communication signalling to sensing signalling, and vice versa. Sensing signalling may be transmitted with a sensing beam and / or isotropically or with a default beam; it may be received with a reception beam, or with a default or isotropic reception. A sensing beam may be swept through a spatial angle, e.g. according to a sweeping scheme to perform sensing in the spatial angle. 465

[0064] A DFT-s-OFDM based wave-form may be a wave-form constructed by performing a DFT- spreading operation on modulation symbols mapped to a frequency interval (e.g., subcarriers), e.g. to provide a time- variable signal. A DFT-s-OFDM based wave-form may

[0065] P111608W001 13 / 77 also be referred to a SC-FDM wave-form. It may be considered to provide good PAPR characteristics, allowing optimised operation of power amplifiers, in particular for high 470 frequencies. In general, the approaches described herein may also be applicable to SingleCarrier based wave-forms, e.g. FDE-based wave-forms. Communication, e.g. on data channel / s and / or control channel / s, may be based on, and / o utilise, a DFT-s-OFDM based wave-form, or a Single-Carrier based wave-form.

[0066] Communication may in particular on multiple communication links and / or beams and / or 475 with multiple targets (e.g., TRPs or other forms of transmission sources also receiving) and / or multiple layers at the same time; different reference signallings for multiple transmission or reception may be based on different sequence roots and / or combs and / or cyclic shifts. Thus, high throughput may be achieved, with low interference. In general, different reference signallings (e.g., of the same type) may be associated to different transmission 480 sources and / or beams and / or layers, in particular if transmitted simultaneously and / or overlapping in time (e.g., considering different timing advance values if transmitted in uplink). For example, there may be first reference signalling transmitted using a first transmission source and / or first beam and / or first layer, and second reference signalling transmitted using a first transmission source and / or first beam and / or first layer. 485

[0067] There is also described a program product comprising instructions causing processing circuitry to control and / or perform a method as described herein. Moreover, a carrier medium arrangement carrying and / or storing a program product as described herein is considered. An information system comprising, and / or connected or connectable, to a radio node is also disclosed. 490

[0068] Brief description of the drawings

[0069] The drawings are provided to illustrate concepts and approaches described herein, and are not intended to limit their scope. The drawings comprise:

[0070] Figure 1, showing an exemplar radar cube;

[0071] Figure 2, showing an exemplary error elipse; 495

[0072] Figure 3, showing results of an exemplary scenario;

[0073] Figure 4, showing an exemplary sensing scenario;

[0074] Figure 5, showing results of an exemplary scenario;

[0075] Figure 6, showing an examplary sensing scenario;

[0076] P111608W001 14 / 77 Figure 7, showing an exemplary wireless device; and 500

[0077] Figure 8, showing an exemplary network node.

[0078] Detailed description

[0079] Joint communication and sensing (JCAS) is emerging as one of the use cases in future wireless cellular communication such as 6G. In one approach, it may be considered using cellular communication (radio) nodes (base stations / UEs) to sense the environment, e.g., 505 by using the communication-specific signals and / or dedicated sensing signals, and provide information such as location, shape, speed, etc. of the objects in the surrounding. Some of the possible applications of sensing using cellular communication systems are traffic monitoring and crash avoidance, gesture / motion detection, presence detection of objects or persons, vital sign detection, environment mapping, particle / pollution detection, etc. 510 In general, joint communication and sensing may comprise and / or be based on utilising radio nodes for a communication network for sensing and / or radar operation, e.g. sharing radio circuitry and / or antennas and / or resources.

[0080] Tighter integration of communication and sensing may be provided. By reusing existing macro infrastructure, sensing can be added at low cost. Sensing can be using both to 515 improve network performance and to add new features such as traffic monitoring and surveillance. If the same hardware is used for radar and communication, performance and capacity of both systems may suffer. Radar signalling may be considered sensing signalling and vice versa in this discussion. For example, to monitor a traffic intersection, detect approaching vehicles and their speed, a large part of available resources may be 520 used for radar operation, lowering resources available for communication. Approaches described herein facilitate efficient operation of joint communication and sensing, with limited impact of sensing operation on communication capabilities.

[0081] Sensing can be done either using a single node, i.e. the transmitter and receiver are co-located and / or associated to the same radio node (mono-static) or multiple nodes, in 525 which case the transmitter (s) and receiver(s) may be in different locations (multi-static); in some variants of multi-static approaches, one or more nodes may be have transmitter and receiver and / or may operate for transmitting and receiving. One particular challenge with the mono-static scenario in joint communications and sensing is that if the same radio node is used for simultaneous transmission and reception, then it has to be capable of 530 full-duplex communication (the received signals will be shifted in time to the transmitted one, but usually overlap in time). This may be particularly challenging, since the received signal levels in a cellular communications may be lower than the transmitted signals by several orders of magnitude; reception of such signals may be facilitated by certain

[0082] P111608W001 15 / 77 approaches or designs considered to reduce interference. In a mono-static radar setup, 535 simultaneous transmission and reception (and thus full duplex) is unavoidable if it should be possible to detect targets close to the base stations (targets far enough away may be less challenging from this point of view since the echo (reflected signal) may arrive after the BS stopped transmitting). Bi-static sensing may represent a scenario with one transmitter and one receiver. 540

[0083] In a monostatic radar, transmitter and receiver nodes may be collocated (e.g., on and / or associated to the same node). The transmitter sends a waveform that is reflected by the environment and targets. These reflections are received by the receiver and processed, e.g. by the receiver or another connected entity, to obtain information about the environment and targets. 545

[0084] A radar pulse that spans one or multiple OFDM symbols would allow an easy integration of radar into the communication system. For example, for NR 30 kHz numerology, the OFDM symbol duration (incl. cyclic prefix) is approximately 36 / zs. A radar pulse spanning a single OFDM symbol duration would have the same length. A round trip time of 36 / zs corresponds to single-way distance of 5.4 km. For objects closer than 5.4 km, 550 the echo would arrive while the transmitter still transmits the radar pulse. The reflected signal may be received in presence of strong self-interference (the transmitted signal that leaks into the receiver). A receiver capable of handling such self- interference is often called a full-duplex capable receiver. Full-duplex puts high requirements on the receiver and potentially also on the transmitter (e.g. linearity), especially for high transmit powers 555 where high self-interference cancellation is required.

[0085] In bistatic radar (and more generalised, for multistatic radar), transmitter and receiver are not collocated and the setup thus avoids problems outlined above for monostatic radar. Distance observations may be based on measuring the Time of Flight (ToF) from transmitter via the target to the receiver. In a simple case, where the signal is reflected 560 off the target and nothing else, all possible target positions for a measured ToF value are located on an ellipsis (in 3D: ellipsoid) with focal points given by transmitter and receiver location. To determine the target position, transmitter and receiver node location, ToF, and Angle of Departure (AoD) or Angle of Arrival (AoA) must be known. One of the angles is needed to determine the target location on the ellipse given by transmitter and 565 receiver location and ToF.

[0086] In order to accurately determine ToF, transmitter and receiver need to be accurately synchronized in time. This is may be one of the challenges for bi- and multistatic radar. In multistatic radar, more than two nodes participate in the radar operation. For example, with one transmitter and three receivers, three ellipses can be determined and the 570

[0087] P111608W001 16 / 77 target is located where the three ellipses intersect each other. For multistatic radar, ToF observations may suffice to locate the target, and angle information may not be needed (but can be used to improve performance). In a communication network, there are several ways to do bi and multistatic sensing. Either the base stations or the UEs can act as sensing transmitters or receivers. Base station — UE links can be used in the downlink, 575 just as well as UE — BS links in the uplink, and BS — BS and UE — UE links.

[0088] In some applications, sensing may improve network performance and / or add new features such as traffic monitoring and surveillance. If the same hardware is used for radar and communication, performance and capacity of both systems may suffer in comparison to using separated dedicated equipment for both. If, for example, a traffic intersection is 580 monitored, to detect approaching vehicles and their speed, significant parts of the available resources (e.g., half) may be required for radar operation.

[0089] The available carrier or system bandwidth in 6G at high frequencies is expected to be very wide, e.g. covering one GHz or more, in particular 5GHz or more. There are several regions with ~6GIIz contiguous spectra (bandwidth) available for high frequencies (above 585 90 GHz).

[0090] Sensing, also referred to as active sensing, may generally refer to transmitting signalling and / or receiving reflection / s of this signalling, e.g. radar signalling and / or communication signalling; Sensing may comprise and / or be based on processing received (reflected) signalling to determine one or more properties of a target object, e.g. position and / or 590 speed (total speed, or a component thereof, e.g. to direction of the receiver) and / or shape and / or size and / or velocity (total, or a component thereof) and / or surface structure and / or reflexivity of a reflecting object, e.g. based on one or more signalling characteristics of the transmitted (radar) signalling and / or one or more signalling characteristics of the received (radar) signalling, and / or based on one or more changes and / or shifts and / or 595 differences and / or delta (e.g., one value subtracted from another value) between one or more signalling characteristics of the transmitted signalling and / or received signalling. For a multi-static case, the receiving node may be informed about the one or more signalling characteristics, e.g. based on configuration (e,g, higher layer signalling like RRC signalling or MAC layer signalling, or Fl signalling, or X2 signalling, or physical layer 600 signalling) .

[0091] Sensing signal processing is described in the following. In active sensing, a signal or signalling like radar signalling is transmitted to probe the environment, and the received reflections are used to estimate for example position and / or speed and / or velocity of the object / s in a range covered by the signalling. Depending on the required accuracy and 605 range for the position and speed of the object / s, there are certain requirements on the

[0092] P111608W001 17 / 77 duration, bandwidth, and periodicity of the signalling or signal to be used.

[0093] In a typical pulse radar, a sequence of wave- forms or symbols or signals (e.g., spreading codes) with chip duration T and signal integration duration of T^nt with periodicity Trare transmitted for a duration Tf (there is one transmission or signalling occurrence 610 in each Tr). The choice of these parameters determine range (sensing range, if waveforms are identical), range resolution, velocity or speed (speed or velocity range), and speed / velocity resolution for sensing targets. L and M may represent integer numbers (of chips or symbols in a period corresponding to the periodicity, and number of transmission occurrences in Tf, respectively). 615

[0094] Depending on the use case, a sensing signal design may be tailored to meet fundamental requirements one or more of Range resolution (Rr) representing the minimum distinguishable distance between two objects; and / or (Unambiguous) range (Ru), representing the maximum distance where an object can be located for (e.g., guaranteed, and / or within a desired error range) detection; and / or Speed or Velocity range (uM), representing the 620 maximum range of speed or velocity of moving object that can be measured; and / or Speed or Velocity resolution (ur), representing the smallest change in the speed or velocity of the moving object that can be measured.

[0095] The parameters of a sensing signal (which in general may also be referred to as sensing signalling, or radar signal, or radar signalling) may include a bandwidth, like a minimum 625 bandwidth, and / or a duration like a minimum duration of the sensing signal, and / or a a minimum and / or maximum repetition periodicity, and / or a minimum duration of the sensing frame (a time interval in which sensing signalling may be transmitted), may be designed such above sensing requirement / s are met. Table 1 below shows the relationship between the sensing requirements and the sensing signal parameters, with c denoting the 630 speed of light, fcrepresenting the carrier frequency.

[0096] Table 1

[0097] At the receiver, the reflected signal (e.g., reflected from one or more objects and / or from the surrounding) is received, and may be matched and / or filtered with the transmitted 635 wave-form to give the delay (e.g., representing the distance of the object), and / or the phase rotation between consecutive wave forms, e.g. representing the Doppler shift due to the movement of the object. In general, the above-mentioned signal generation and

[0098] P1116D8WO01 18 / 77 receiver processing may be common (and / or used similarly) to all types of sensing methods and signals, and is not limited to a pulse radar. In a joint communication and sensing 640 scenario, the choice of wave-form may depend on what wave-form is more suitable for both communication and sensing, although this is not a requirement, and the wave-forms for the two systems may be different. The following description of receiver processing may be independent of the wave-form type and may be equally or analogously applicable to different wave-forms , as well as any typical communication wave-form such as OFDM, 645 DFT-s-OFDM, etc. As one example, the wave-form may comprise, and / or be based on, and / or represent, and / or be one or several OFDM or DFT-S-OFDM symbols ( or even sub-symbols), and / or block symbols, as it is the common wave- form used in most of the existing wireless access links (used for wireless and / or cellular communication). A sensing signal may be based on OFDM symbols, in particular a train of OFDM symbols as sensing 650 signalling; such train may be repeated a plurality of times, e.g. according to a periodicity, e.g. in one or more sensing frames. A train of symbols may represent a sequence of symbols, each of which may carry and / or represent a sequence of modulation symbols (e.g., for a OFDM based wave-form), which may be mapped to frequency domain; each symbol may carry the same or a different sequence. In some cases, a sequence may be 655 mapped over multiple symbols, e.g. frequency first. A common receiver processing may comprise and / or be based on performing an FFT per sequence occurrence, e.g. a train of symbols, for example transforming delay domain into subcarrier (frequency) domain, and an IFFT per subcarrier across the sequence occurrences, for example transforming time-domain into Doppler domain. Then peaks, e.g. all peaks, beyond a threshold may 660 be identified, and the delay and Doppler values associated with each peak (representing a target) may be considered corresponding to delay and velocity or speed of the target.

[0099] A sensing receiver may perform radar or sensing processing to estimate range and / or Doppler shift of the target. It may also estimate the direction in which the target is, e.g., in case the receiver has multiple antennas. To estimate range, Doppler shift and 665 direction to the user, the sensing receiver may correlate the received signal with delayed and frequency shifted versions of the known transmitted signal. A result of this correlation may comprise a delay — Doppler profile. Note that in some applications, only estimating range or Doppler shift might be sufficient. To estimate the direction of the target, the delay — Doppler profiles of the different antennas may be correlated with the steering 670 vector of the array for different values of the incidence angle. The result of this correlation may be represented or representable as a radar cube, which is illustrated in Figure 1.

[0100] The target, if illuminated (struck by sensing signalling) properly, may create a ’’peak” in the radar cube at the values corresponding to its range, Doppler shift and direction.

[0101] In this multi-dimensional function, a ’’peak” may be considered a point in the function 675

[0102] P111608W001 19 / 77 where the modulus of the function has a distinct maximum (e.g., relative or absolute maximum). Observations of the range, Doppler shift and direction can thus be obtained by identifying where in the radar cube the peak of the target is. If observations from multiple sensing receivers are available, these may be fused to produce an estimate of the target position and velocity (e.g., for one or more targets / objects). The quality 680 of these estimates may be characterised through an error covariance matrix. For ease of illustration, this error covariance matrix will be explained for a 3D position estimate. The theory can be generalized to position and velocity estimates, which are 6-dimensional.

[0103] If the 3D error vector of a position estimate (which may correspond to a position in real space, or a position in a parameter space, e.g., represented by and / or based on 685 a radar cube) is e = trueposition-estimatedposition, then the covariance matrix that characterises the estimation quality may be defined or represented as C = E[eeT].

[0104] Often the covariance matrix is computed approximately from the covariance of the observations (e.g., parameter space of and / or including range, Doppler shift and angles); a Taylor expansion of the system equations may be used, cf. the Cramer — Rao bound. 690 The error covariance matrix is a function of the system equations, and also a function of the transmitter and receiver positions. Varying these positions will thus affect the error covariance matrix. This covariance matrix may be represented by an (error) ellipsoid (or an analogous structure in N-dimensional space for N parameters), e.g., based on its eigenvalues and eigenvectors that shows how the estimation error is distributed, see Figure 695 3. The error ellipsoid is often wide in one direction (corresponding to large eigenvalues) and narrow in other directions (corresponding to small eigenvalues). Such a shape would indicate that the position estimate is bad or relatively unreliable in the wide direction and better / good or more reliable in the other direction / s.

[0105] Since it oftentimes is easier to illustrate the error performance through a scalar value 700 instead of through a covariance matrix, some standard figures of merits (error parameters) may be used. A family of such parameters or values is the dilution of precision (DOP), which are different functions of the error covariance matrix. The “position DOP” (PDOP) is, for example, the square-root of the trace of the error covariance matrix. Horizontal DOP and vertical DOP values are also sometimes used. Other forms of DOP values may 705 be considered, e.g., based on other paramerters. A small DOP value would indicate that a good position estimate is possible and, the other way around, a large would indicate a bad estimate.

[0106] The covariance matrix varies with the target position and, therefore, the DOP varies with the target position as well. Figure 3 shows a map of a simple setting where two UEs and 710 one base station perform sensing based on range observations from the two UE — BS links.

[0107] P111608W001 20 / 77 The map shows how the square-root of the trace of the covariance matrix, which gives the expected standard deviation of the error, varies for different target positions. In addition, the error ellipse is shown for a grid of target positions. It can be seen that the error is small and equally distributed in the x and y directions in between the two UEs. It can 715 also be seen that the error is larger outside the triangle formed by the UEs and the base station, where the error also is small in the radial direction and large in the tangential direction. On four lines, between the UEs and the base station and in rays starting in each UE and extending outwards, the error is large and sensing does not work for targets on or close to these lines. 720

[0108] If the sensing performance over an area should be evaluated, the DOP has to be integrated over that area. Such an integral may be considered to indicate the average sensing performance in the area. In some cases, average performance is not the most important metric, but rather a certain percentile (for example the 99%ile), then the DOP distribution over the area can be computed, from which the percentile can be obtained. 725

[0109] DOP may be a normalized measure, which is not affected by signal strength (SNR). Not-normalized versions of DOP can be used to evaluate the sensing performance when the SNR of the sensing link (the sensing link may refer to the connection of transmitter and receiver of sensing signalling, different links may have different transmitter and / or receiver) is known. The consideration of SNR can be important, especially if different 730 links have different SNRs.

[0110] Sensing may be based on measuring the direct signal from Tx — target — Rx. Sensing performance is, however, greatly improved if also reflections in known surfaces are considered as well. In Figure 4, such a scenario is shown, where the measurement from a single UE generates two observed ranges, one from the direct link 1 and one from the reflected link 735 2. To account for the second observation in the covariance matrix computation, and in the DOP, the range observation of the reflected link may be treated as if it was related to a different, virtual base station that is located at the actual base station position mirrored in the known surface, and any AoA observation can be used in the same way after it is mirrored in the surface. Practically, the second observation thus contributes to the 740 sensing performance as an additional base station and an additional observation from a different angle would.

[0111] Specifically, Figure 4 shows a UE in line-of-sight that is additionally seen in a reflection on a wall. The reflection can equivalently be seen as a transmission to a virtual base station located in the mirrored position of the base station in the wall. Furthermore, 745 the reflected link can make UEs, for which the direct link is blocked, useful for sensing, thus extending the coverage to areas that otherwise would be shadowed by blockers. For

[0112] P111608W001 21 / 77 example, there may be scenarios in which the direct link through the target is blocked by a wall and only a reflected link on another wall is observed. Here, the UE still could contribute to the sensing performance through the reflected observation. This effect may 750 be captured in the covariance matrix and the DOP measure.

[0113] The LTE and NR standards specify various reference signals that the UE can transmit in the uplink, and / or that the base station can use for demodulation of data symbols and / or for determining channel conditions, based on which scheduling and configuring data transmissions in the uplink and / or in the downlink may be performed. Configuring 755 may comprise configuring and / or selecting beamforming weights, MCS, number of MIMO streams, code rate, etc. Examples of such (uplink) reference signals are DMRS and SRS, where the former are transmitted and beamformed along with data, while the latter can be scheduled by the base station in many different configurations. The configurations of the SRS transmissions may indicate or include assigning of signaling as periodic or 760 aperiodic. Aperiodic signaling is, as it sounds, transmitted on a per need basis, whereas the periodic is an always on, repetitive signaling (always on may refer to signaling occuring periodically, e.g. every M ms or N slot or subframes, with N being an integer of 1 or larger, and M being an integer or real number larger than 0). The periodicity (e.g. between 2 ms and 160 ms in LTE for periodic SRS transmissions, or event-driven for aperiodic SRS 765 transmissions), the number of UE antennas to sound from and if antenna hopping should be allowed, the bandwidth of the SRS transmissions, frequency hopping and repetition rates, etc, may be configured. There are different ways in which SRS transmissions can be configured. Different configurations may be used for different needs associated with communication. 770

[0114] Due to hardware limitations, the time and frequency synchronization of the transceivers involved in the sensing measurements is not necessarily good enough to do coherent processing of the radar channel, which is important in sensing in order to observe Doppler shifts. The time and frequency synchronization of communication hardware is typically sufficient for communication purposes, but not for sensing purposes, and additional syn- 775 chronization may be needed to enable coherent radar processing.

[0115] To obtain an observation of a target’s range, speed and angles, the peak of the target has to be distinguished from peaks stemming from other objects in the environment. Other objects that are not of interest to the sensing user are referred to as “clutter” , and techniques related to distinguishing target from clutter are referred to as “clutter 780 suppression” . Clutter suppression may be based on Doppler filtering, considering that for most cases the fact is true that the target is moving and has a different Doppler than the, mostly stationary, environment.

[0116] P111608W001 22 / 77 It should be noted that the Doppler shift is related to the radial movement of the target, and tangential movement still would result in zero Doppler shift. Thus, movement does 785 not directly translate to a Doppler shift, so it might be that a moving target still is not distinguishable from clutter. For example, a target moving along the bistatic range ellipse would have zero Doppler and would be difficult to distinguish from clutter based on Doppler shift.

[0117] Since UE locations are random, it may happen that the sensing performance of a sensing 790 system that employs UEs as sensing nodes can be bad if the locations of the UEs are unfortunately distributed. Sensing performance might also be negatively affected because UEs may be moving in an unknown way. If an area has many UEs, it may be wasteful to let all UEs send sensing signals, e.g., using all UEs may not significantly improve sensing performance compared to using a subset of the UEs. 795

[0118] Approaches of selecting UEs for sensing in an ISAC system are considered. The UEs are selected to improve and / or provide desired ISAC performance, while avoiding the use of an excessive amount of UE resources, to improve sensing performance and reduce the impact on communication. The system may operate in multi-static mode, e.g., including at least one base station and / or stationary node (e.g., as receiver of sensing signalling, 800 and / or transceiver) and one or more non-stationary nodes, e.g., UEs, for example as transmitter of sensing signalling and / or transceiver.

[0119] UEs may be selected based on their impact on the DOP of the position estimation and based on the UE mobility. Factors such as reducing the number of UEs, reducing impact on communication performance etc, may also be considered. Selecting a UE, or a group 805 or number of UEs, may include scheduling the UEs for transmission of sensing signalling and / or reference signalling for sensing, e.g., SRS; such signalling may be referred to as second sensing signalling and / or sensing operation signalling. Second sensing signalling and / or sensing operation signalling may be scheduled for transmission, and / or be transmitted by, and / or received from, a group of UEs, which may be referred to as operation 810 group or second group. Selecting may be based on evaluating received signalling, e.g., sensing signalling and / or reference signalling for sensing, which may be scheduled and / or received before selecting, and may be referred to as first sensing signalling and / or selection signalling. Selection signalling or first sensing signalling may be scheduled for transmission, and / or may be transmitted by, and / or received from UEs from a first group 815 of UEs, which may be referred as selection group. The first group of UEs may comprise the second group of UEs, and / or may include more UEs than the second group. The second group of UEs may be a subset of the first group of UEs.

[0120] First sensing signalling may comprise signalling from one or more UEs; the signalling from

[0121] P111608W001 23 / 77 different UEs may have one or more same parameters and / or one or more different param- 820 eters. Same parameters may in particular refer to frequency and / or spectrum. Different parameters may differ for example regaring to signalling sequence and / or timing. First sensing signalling may comprise a plurality or group or set of signallings from different transmitters and / or sources and / or nodes and / or UEs. Second sensing signalling may comprise signalling from one or more UEs; the signalling from different UEs may have 825 one or more same parameters and / or one or more different parameters. Same parameters may in particular refer to frequency and / or spectrum. Different parameters may differ for example regaring to signalling sequence and / or timing. Second sensing signalling may comprise a plurality or group or set of signallings from different transmitters and / or sources and / or nodes and / or UEs. First sensing signalling may be based on a first set 830 of parameters, e.g., regarding timing and / or frequency and / or signalling sequences; the parameters used for individual sensing signalling may be elements of the first set. Second sensing signalling may be based on a second set of parameters, e.g., regarding timing and / or frequency and / or signalling sequences; the parameters used for individual sensing signalling may be elements of the second set. The second set may be a subset of the 835 first set, and / or the first set and the second set may be the same set. In some cases, the first set and second set may overlap partially and / or completely, or may be disjunct sets. Selecting may be based on determining one or more DOP characteristics and / or parameters, e.g., based on received first sensing signalling. A group of UEs may be considered to be a set of UEs, and / or may be represented or representable as a list of UEs (e.g., as 840 stored in a memory of a base station or radio node or sensing node).

[0122] An advantage of using a subset of the UEs for sensing and not all the UEs may be reduced resource usage. Sensing performance may be maintained and / or detrimental impact on communication performance may be mitigated.

[0123] To select which UEs to employ in the sensing, the base station may regularly cycle through 845 all available UEs, and may evaluate how much each one of them could improve DOP, e.g., an un-normalized (SNR dependent) DOP. If a UE does not improve DOP significantly (e.g., based on a threshold, e.g., a minimum threshold), it is not chosen / selected and, if the UE improves (e.g., based on a threshold value, which may be the minimum threshold) the DOP, it is chosen / selected. A threshold like a minimum threshold may indicate a DOP 850 improvement (e.g., reduction of DOP size in at least one direction and / or dimension and / or parameter), and / or improvement in accurracy, e.g., in at least one dimension and / or direction and / or parameter). Cycling to a UE may include scheduling the UE for transmission of sensing signalling, and / or receiving and / or monitoring for sensing signalling from the UE; the sensing signalling may be first sensing signalling. 855

[0124] P111608W001 24 / 77 In general, UE selection (e.g., determing UEs for a second group of UEs) may be based on one or more factors and / or criteria, e.g., alternatively or additionally to criteria and / or factor / s pertaining to DOP. Factors and / or criteria as the ease of time and phase synchronization of the UE, and / or suitability for clutter suppression, may alternatively or additionally be considered and / or accounted for when choosing or selecting on or more 860 UEs, and / or selecting may be based on one or more of such factors and / or criteria. For example, a list of chosen or selected UEs (e.g., the second group of UEs) may be limited to stationary UEs, or UEs that move sufficiently little, since UE movement may affect how easy it is to synchronize its signals. In general, one or more factor / s and / or critera may pertain to a collective parameter, e.g., to a group of UEs, and / or may be target-specific 865 and / or UE-specffic. A target may be an intended target for sensing, and / or an object, e.g., to be detected and / or tracked. In general, the second group of UEs may be selected target-specific, and / or area-specific, and / or cell-specific, and / or task-specific (e.g., object detection and / or tracking), and / or parameter-range-specific (e.g., for detecting and / or tracking in a range of target speed and / or velocity, e.g., for one or more targets). 870

[0125] A list of chosen UEs (e.g., second group of UEs) may be selected based on, and / or be limited to those, UEs that are expected to result in non-zero Doppler observations of the target, and / or based on speed or velocity, e.g., based on relative speed and / or velocity (e.g., between target and UE / s). Other factors that the choice or selection (in this context, choice and selection as well as selecting and chosing may be used interchangeably) may 875 be based on are and / or may include: number of UEs and resource overhead, task to be performed, and / or location or position and / or geometric area of UE / s and / or target (e.g., which area the node or target is in), and / or presence of obstacles and / or clutter, etc.

[0126] It is Noted that the position of the intended sensing target (target or intended targer) may affect the DOP that is used to choose or select the UE, and that the direction of 880 movement of the target may affect the expected Doppler shift that is used to choose or select the UE.

[0127] Since the set of available UEs (e.g., first group of UEs) may change over time, and since UEs move, the algorithm may be repeated with a sufficiently long interval to keep the list of UEs up-to-date. If all UEs have remained at their positions since last time, no update 885 is needed. The search space (e.g., of UEs to be cycled through and / or being included in the first group of UEs) may also be reduced by prefiltering the set or group, for example by only keeping stationary UEs.

[0128] A UE might be evaluated based on it transmitting a test signal (SRS or DMRS, and / or first sensing signalling), and / or by evaluating its position, orientation, motion and present 890 resource usage. Since additional observations through traceable reflections of a target may

[0129] P111608W001 25 / 77 reduce DOP, and / or may improve sensing performance, the impact of such reflections may be taken into account. To determine if a target is seen through a traceable reflection, the UE may be asked or scheduled to send a test signal, whose delay — Doppler profile may reveal the existence of traceable reflections. Figure 5 shows a Doppler / path length 895 diagram for an exemplary scenario, in which three peaks from different reflection paths can be seen.

[0130] Figure 6 shows an example scenario, where six UEs 10 are connected to a base station (e.g, for communication). There is a sensing area, marked in grey, and for the sensing operation group, there have been selected three UEs to perform sensing in this sensing 900 area (geometric area of the target). UEs of the second group of UEs / the sensing operation group are filled dark, the additional UEs which are members of the first group, but not the second group, are filled white. The three dark UEs may have been selected to sense objects in the grey area, to illuminate objects from four different directions (one via reflection), and thus minimize DOP. 905

[0131] Communication nodes involved in sensing may for example comprise, and / or sensing may comprise and / or be based on, UEs, base stations, or a combination thereof, including base-station transmission of signal for sensing, UE reception of signal for sensing; and / or UE transmission of signal for sensing, base-station reception of signal for sensing; and / or base-station transmission of signal for sensing, base-station reception of signal for sensing; 910 and / or UE transmission of signal for sensing, UE reception of signal for sensing. A communication node involved in sensing may be referred to as sensing node; some sensing nodes may be for sensing only.

[0132] For cellular communications, such as 5G, sensing signalling and / or a sensing signal may comprise a DL reference signal, or a UL reference signal, or a sidelink reference signal. 915 Sensing signalling and / or a sensing signal may be any of the existing signals, such as DL positioning reference signal (PRS), CSLRS, DM-RS; and UL sounding reference signal (SRS) or uplink DMRS, a new sensing / positioning specific signal, or a communication signal itself (e.g., control signalling or data signalling, e.g. on a PUCCH or PUSCH or PDCCH or PDSCH). Combinations of these signals may also be used. 920

[0133] Sensing may be based on estimating a channel based on known reference signals, it sensing may be based on data. In this case, either data may be known at the receiver (e.g. monostatic scenario) or it may be be decoded first, so that the channel can be estimated subsequently. Communication may be based on (DFTS-)OFDM; OFDM based radar may be used to allow re-use of as much hardware as possible. 925

[0134] Figure 7 schematically shows a radio node, in particular a wireless device or terminal 10

[0135] P111608W001 26 / 77 or a UE (User Equipment). Radio node 10 comprises processing circuitry (which may also be referred to as control circuitry) 20, which may comprise a controller connected to a memory. Any module of the radio node 10, e.g. a communicating module or determining module, may be implemented in and / or executable by, the processing circuitry 20, in 930 particular as module in the controller. Radio node 10 also comprises radio circuitry 22 providing receiving and transmitting or transceiving functionality (e.g., one or more transmitters and / or receivers and / or transceivers), the radio circuitry 22 being connected or connectable to the processing circuitry. An antenna circuitry 24 of the radio node 10 is connected or connectable to the radio circuitry 22 to collect or send and / or amplify 935 signals. Radio circuitry 22 and the processing circuitry 20 controlling it are configured and / or adapted for cellular communication with a network, e.g. a RAN as described herein, and / or for sidelink communication (which may be within coverage of the cellular network, or out of coverage; and / or may be considered non-cellular communication and / or be associated to a non-cellular wireless communication network), and / or may be adapted 940 or configured for sensing operation. Radio node 10 may generally be adapted to carry out any of the methods of operating a radio node like terminal or UE disclosed herein; in particular, it may comprise corresponding circuitry, e.g. processing circuitry, and / or modules, e.g. software modules. It may be considered that the radio node 10 comprises, and / or is connected or connectable, to a power supply. A DFE may be considered part of 945 radio circuitry; an analog frontend may be associated to radio circuitry and / or antenna circuitry.

[0136] Figure 8 schematically shows a radio node 100, which may in particular be implemented as a network node 100, for example an eNB or gNB or similar for NR. Radio node 100 comprises processing circuitry (which may also be referred to as control circuitry) 120, 950 which may comprise a controller connected to a memory. Any module, e.g. transmitting module and / or receiving module and / or configuring module of the node 100 may be implemented in and / or executable by the processing circuitry 120. The processing circuitry 120 is connected to control radio circuitry 122 of the node 100, which provides receiver and transmitter and / or transceiver functionality (e.g., comprising one or more 955 transmitters and / or receivers and / or transceivers), and / or may be adapted or configured for sensing operation and / or communication operation. An antenna circuitry 124 may be connected or connectable to radio circuitry 122 for signal reception or transmittance and / or amplification. Node 100 may be adapted to carry out any of the methods for operating a radio node or network node disclosed herein; in particular, it may comprise 960 corresponding circuitry, e.g. processing circuitry, and / or modules. The antenna circuitry 124 may be connected to and / or comprise an antenna array. The node 100, respectively its circuitry, may be adapted to perform any of the methods of operating a network node

[0137] P111608W001 27 / 77 or a radio node as described herein; in particular, it may comprise corresponding circuitry, e.g. processing circuitry, and / or modules. The radio node 100 may generally comprise 965 communication circuitry, e.g. for communication with another network node, like a radio node, and / or with a core network and / or an internet or local net, in particular with an information system, which may provide information and / or data to be transmitted to a user equipment. A DFE may be considered part of radio circuitry; an analog frontend may be associated to radio circuitry and / or antenna circuitry. 970

[0138] In general, the wireless device and / or network node may operate in, and / or the communication signalling may be in TDD operation. It should be noted that the transmission of signalling from transmission sources may be synchronised and simultaneous; a shift in time may occur due to different propagation times, e.g. due to different beams and / or source locations. 975

[0139] A data block may refer to a transport block, or a code block or a code block bundle. A code block may comprise and / or represent a number of (information) bits representing information (e.g., data or control information), to which there may be associated, and / or which may further include, bits for error detection coding, e.g. CRC. The bits for error detection coding may be determined based on the (information) bits, and / or may be error 980 detection bits for the (information) bits. A code block bundle may comprise one or more code blocks; wherein each code block may have associated to it, and / or comprise, error correction bits. The error correction bits in a code block bundle may each pertain to an associated code block; error correction bits may be specific to only one code block, e.g. determined based on bits of only one code block. Different bits and / or groups of bits 985 may be associated to different code blocks. Error correction bit / s associated to a code block may be associated to a single code block; this may refer to the error correction bits indicating correctness / incorrectness of the single code block, and / or calculated and / or determined based only on (information) bits of the single code block. Information bits may represent data and / or control information, e.g. associated to a data channel (data in- 990 formation / bits) and / or control channel (control information / bits) code block bundle may be a data block without error correction coding pertaining to more than one code block.

[0140] A transport block may comprise error detection coding pertaining to a plurality of code blocks, e.g. covering the code blocks it consists of. A transport block may comprise one or more code blocks. It may be considered that a data block may be associated to, and 995 or subject to, and / or correspond to, a, one and / or a single acknowledgement process, e.g. a specific HARQ process, which may correspond to and / or be represented by a HARQ identifier. A code block may correspond to a subpattern of an acknowledgement information bit pattern. In some cases, a data block may correspond and / or pertain and / or be subject to a plurality of acknowledgement processes, e.g. if there is one acknowledgement 1000

[0141] P111608W001 28 / 77 process per code block of the data block.

[0142] A data block may comprise and / or represent information bits, which may be data bits (e.,g., user data) and / or control information bits; the information bits may be associated to one or more data or control channels, e.g. transport channels and / or logical channels, and / or may be mapped to a specific and / or single physical channel, in particular a physical 1005 data channel, or in some cases, a physical control channel (in which case it may or may not be associated to a higher layer channel like a transport channel or logical channel). A data block may represent bits intended for transmission, e.g. encapsulating one or more higher layer data packets, e.g. one or more MAC layer data packets, e.g. one or more PDUs (Protocol Data Unit) and / or SDUs (Service Data Unit); error correction bits, e.g. 1010 CRC; may be added in physical layer processing. It may be considered that bits of a data block are subject to physical layer processing like coding (e.g., forward error coding and / or adding error correction coding) and / or rate matching and / or scrambling, and / or modulation. Modulation may correspond to mapping of bits of the processed data block to modulation symbols, e.g. according to a modulation scheme and / or to a modulation 1015 space. The modulation symbols may be represented as a bit sequence until they are subject to analog conversion (or vice versa for reception).

[0143] A wireless device may in general comprise processing circuitry and / or radio circuitry, in particular a receiver and / or transceiver and / or transmitter, for performing measurement and / or to control beam switch and / or control beam-forming and / or receive and / or 1020 transmit signalling like communication signalling and / or sensing signalling. The wireless device may in particular be implemented as terminal or a user equipment. However, in some cases, e.g. relay and / or back-link and / or IAB scenarios, it may be implemented as network node or network radio node. A network node may in general comprise processing circuitry and / or radio circuitry, in particular a receiver and / or transceiver and / or trans- 1025 mitter, for transmitting reference signalling and / or a beam switch indication and / or for beam switching and / or to control beam switch and / or control beam-forming and / or receive and / or transmit signalling like communication signalling and / or sensing signalling.. The second radio node may in particular be implemented as a network node, e.g. a network radio node and / or base station or a relay node or IAB node. However, in some 1030 cases, e.g. sidelink scenarios, the second radio node may be implemented as a wireless device or terminal, e.g. a user equipment.

[0144] In general, sensing signalling may be based on the same wave-form as the communication signalling. However, it may be based on a different wave-form in some variants. The sensing signalling may be OFDM based, for example, regular OFDM, or spread OFDM 1035 like DFT-s-OFDM, and / or pulse-shaped OFDM, or filter-bank based, or Single Carrier

[0145] P111608W001 29 / 77 based. The communication signalling may be OFDM based, for example, regular OFDM, or spread OFDM like DFT-s-OFDM, and / or pulse-shaped OFDM , or filter-bank based, or Single Carrier based. The sensing signalling may be transmitted in a transmission timing structure corresponding to the transmission timing structure associated to the 1040 communication signalling, e.g. a frame structure, and / or be based on the same or a different numerology as the communication signalling. The timing structure (e.g., symbol duration or allocation unit duration) and / or types of modulation symbols carried by signalling may be based on the wave-form used.

[0146] In general, a block symbol may represent and / or correspond to an extension in time 1045 domain, e.g. a time interval. A block symbol duration (the length of the time interval) may correspond to the duration of an OFDM symbol or a corresponding duration, and / or may be based and / or defined by a subcarrier spacing used (e.g., based on the numerology) or equivalent, and / or may correspond to the duration of a modulation symbol (e.g., for OFDM or similar frequency domain multiplexed types of signalling). It may be considered 1050 that a block symbol comprises a plurality of modulation symbols, e.g. based on a subcarrier spacing and / or numerology or equivalent, in particular for time domain multiplexed types (on the symbol level for a single transmitter) of signalling like single-carrier based signalling, e.g. SC-FDE or SC-FDMA (in particular, FDF-SC-FDMA or pulse-shaped SC-FDMA). The number of symbols may be based on and / or defined by the number 1055 of subcarrier to be DFTS-spread (for SC-FDMA) and / or be based on a number of FFT samples, e.g. for spreading and / or mapping, and / or equivalent, and / or may be predefined and / or configured or configurable. A block symbol in this context may comprise and / or contain a plurality of individual modulation symbols, which may be for example 1000 or more, or 3000 or more, or 3300 or more. The number of modulation symbols in a block 1060 symbol may be based and / or be dependent on a bandwidth scheduled for transmission of signalling in the block symbol. A block symbol and / or a number of block symbols (an integer smaller than 20, e.g. equal to or smaller than 14 or 7 or 4 or 2 or a flexible number) may be a unit (e.g., allocation unit) used for scheduling and / or allocation of resources, in particular in time domain. To a block symbol (e.g., scheduled or allocated) 1065 and / or block symbol group and / or allocation unit, there may be associated a frequency range and / or frequency domain allocation and / or bandwidth allocated for transmission.

[0147] An allocation unit, and / or a block symbol, may be associated to a specific (e.g., physical) channel and / or specific type of signalling, for example reference signalling. In some cases, there may be a block symbol associated to a channel that also is associated to a form 1070 of reference signalling and / or pilot signalling and / or tracking signalling associated to the channel, for example for timing purposes and / or decoding purposes (such signalling may comprise a low number of modulation symbols and / or resource elements of a block symbol,

[0148] P111608W001 30 / 77 e.g. less than 10% or less than 5% or less than 1% of the modulation symbols and / or resource elements in a block symbol). To a block symbol, there may be associated resource 1075 elements; a resource element may be represented in time / frequency domain, e.g. by the smallest frequency unit carrying or mapped to (e.g., a subcarrier) in frequency domain and the duration of a modulation symbol in time domain. A block symbol may comprise, and / or to a block symbol may be associated, a structure allowing and / or comprising a number of modulation symbols, and / or association to one or more channels (and / or 1080 the structure may dependent on the channel the block symbol is associated to and / or is allocated or used for), and / or reference signalling (e.g., as discussed above), and / or one or more guard periods and / or transient periods, and / or one or more affixes (e.g., a prefix and / or suffix and / or one or more infixes (entered inside the block symbol)), in particular a cyclic prefix and / or suffix and / or infix. A cyclic affix may represent 1085 a repetition of signalling and / or modulation symbol / s used in the block symbol, with possible slight amendments to the signalling structure of the affix to provide a smooth and / or continuous and / or differentiable connection between affix signalling and signalling of modulation symbols associated to the content of the block symbol (e.g., channel and / or reference signalling structure). In some cases, in particular some OFDM-based wave- 1090 forms, an affix may be included into a modulation symbol. In other cases, e.g. some single carrier-based wave-forms, an affix may be represented by a sequence of modulation symbols within the block symbol. It may be considered that in some cases a block symbol is defined and / or used in the context of the associated structure.

[0149] Communicating may comprise transmitting or receiving. It may be considered that com- 1095 municating like transmitting signalling is based on a SC-FDM based wave- form, and / or corresponds to a Frequency Domain Filtered (FDF) DFTS-OFDM wave-form. However, the approaches may be applied to a Single Carrier based wave-form, e.g. a SC-FDM or SC-FDE- wave-form, which may be pulse-shaped / FDF-based. It should be noted that SC- FDM may be considered DFT-spread OFDM, such that SC-FDM and DFTS-OFDM may 1100 be used interchangeably. Alternatively, or additionally, the signalling (e.g., first signalling and / or second signalling) and / or beam / s (in particular, the first received beam and / or second received beam) may be based on a wave-form with CP or comparable guard time. The received beam and the transmission beam of the first beam pair may have the same (or similar) or different angular and / or spatial extensions; the received beam and the 1105 transmission beam of the second beam pair may have the same (or similar) or different angular and / or spatial extensions. It may be considered that the received beam and / or transmission beam of the first and / or second beam pair have angular extension of 20 degrees or less, or 15 degrees or less, or 10 or 5 degrees or less, at least in one of horizontal or vertical direction, or both; different beams may have different angular extensions. An ex- 1110

[0150] P111608W001 31 / 77 tended guard interval or switching protection interval may have a duration corresponding to essentially or at least N CP (cyclic prefix) durations or equivalent duration, wherein N may be 2, or 3 or 4. An equivalent to a CP duration may represent the CP duration associated to signalling with CP (e.g., SC-FDM-based or OFDM-based) for a wave-form without CP with the same or similar symbol time duration as the signalling with CP. 1115 Pulse-shaping (and / or performing FDF for) a modulation symbol and / or signalling, e.g. associated to a first subcarrier or bandwidth, may comprise mapping the modulation symbol (and / or the sample associated to it after FFT) to an associated second subcarrier or part of the bandwidth, and / or applying a shaping operation regarding the power and / or amplitude and / or phase of the modulation symbol on the first subcarrier and the 1120 second subcarrier, wherein the shaping operation may be according to a shaping function. Pulse-shaping signalling may comprise pulse-shaping one or more symbols; pulse-shaped signalling may in general comprise at least one pulse-shaped symbol. Pulse-shaping may be performed based on a Nyquist-ffiter. It may be considered that pulse-shaping is performed based on periodically extending a frequency distribution of modulation symbols 1125 (and / or associated samples after FFT) over a first number of subcarrier to a larger, second number of subcarriers, wherein a subset of the first number of subcarriers from one end of the frequency distribution is appended at the other end of the first number of subcarriers.

[0151] In some variants, communicating may be based on a numerology (which may, e.g., be represented by and / or correspond to and / or indicate a subcarrier spacing and / or symbol 1130 time length) and / or an SC-FDM based wave- form (including a FDF-DFTS-FDM based wave-form) or a single-carrier based wave-form. Whether to use pulse-shaping or FDF on a SC-FDM or SC-based wave-form may depend on the modulation scheme (e.g., MCS) used. Such wave- forms may utilise a cyclic prefix and / or benefit particularly from the described approaches. Communicating may comprise and / or be based on beamforming, 1135 e.g. transmission beamforming and / or reception beamforming, respectively. It may be considered that a beam is produced by performing analog beamforming to provide the beam, e.g. a beam corresponding to a reference beam. Thus, signalling may be adapted, e.g. based on movement of the communication partner. A beam may for example be produced by performing analog beamforming to provide a beam corresponding to a reference 1140 beam. This allows efficient postprocessing of a digitally formed beam, without requiring changes to a digital beamforming chain and / or without requiring changes to a standard defining beam forming precoders. In general, a beam may be produced by hybrid beamforming, and / or by digital beamforming, e.g. based on a precoder. This facilitates easy processing of beams, and / or limits the number of power amplifiers / ADC / DC A required 1145 for antenna arrangements. It may be considered that a beam is produced by hybrid beamforming, e.g. by analog beamforming performed on a beam representation or beam

[0152] P111608W001 32 / 77 formed based on digital beamforming. Monitoring and / or performing cell search may be based on reception beamforming, e.g. analog or digital or hybrid reception beamforming. The numerology may determine the length of a symbol time interval and / or the duration 1150 of a cyclic prefix. The approaches described herein are particularly suitable to SC-FDM, to ensure orthogonality, in particular subcarrier orthogonality, in corresponding systems, but may be used for other wave-forms. Communicating may comprise utilising a waveform with cyclic prefix. The cyclic prefix may be based on a numerology, and may help keeping signalling orthogonal. Communicating may comprise, and / or be based on per- 1155 forming cell search, e.g. for a wireless device or terminal, or may comprise transmitting cell identifying signalling and / or a selection indication, based on which a radio node receiving the selection indication may select a signalling bandwidth from a set of signalling bandwidths for performing cell search.

[0153] A beam or beam pair may in general be targeted at one radio node, or a group of radio 1160 nodes and / or an area including one or more radio nodes. In many cases, a beam or beam pair may be receiver-specific (e.g., UE-specffic), such that only one radio node is served per beam / beam pair. A beam pair switch or switch of received beam (e.g., by using a different reception beam) and / or transmission beam may be performed at a border of a transmission timing structure, e.g. a slot border, or within a slot, for example between 1165 symbols. Some tuning of radio circuitry, e.g. for receiving and / or transmitting, may be performed. Beam pair switching may comprise switching from a second received beam to a first received beam, and / or from a second transmission beam to a first transmission beam. Switching may comprise inserting a guard period to cover retuning time; however, circuitry may be adapted to switch sufficiently quickly to essentially be instantaneous; 1170 this may in particular be the case when digital reception beamforming is used to switch reception beams for switching received beams.

[0154] A reference beam (or reference signalling beam) may be a beam comprising reference signalling, based on which for example a of beam signalling characteristics may be determined, e.g. measured and / or estimated. A signalling beam may comprise signalling like 1175 control signalling and / or data signalling and / or reference signalling. A reference beam may be transmitted by a source or transmitting radio node, in which case one or more beam signalling characteristics may be reported to it from a receiver, e.g. a wireless device. However, in some cases it may be received by the radio node from another radio node or wireless device. In this case, one or more beam signalling characteristics may 1180 be determined by the radio node. A signalling beam may be a transmission beam, or a reception beam. A set of signalling characteristics may comprise a plurality of subsets of beam signalling characteristics, each subset pertaining to a different reference beam.

[0155] Thus, a reference beam may be associated to different beam signalling characteristics.

[0156] P111608W001 33 / 77 A beam signalling characteristic, respectively a set of such characteristics, may represent 1185 and / or indicate a signal strength and / or signal quality of a beam and / or a delay characteristic and / or be associated with received and / or measured signalling carried on a beam. Beam signalling characteristics and / or delay characteristics may in particular pertain to, and / or indicate, a number and / or list and / or order of beams with best (e.g., lowest mean delay and / or lowest spread / range) timing or delay spread, and / or of strongest and / or 1190 best quality beams, e.g. with associated delay spread. A beam signalling characteristic may be based on measurement / s performed on reference signalling carried on the reference beam it pertains to. The measurement / s may be performed by the radio node, or another node or wireless device. The use of reference signalling allows improved accuracy and / or gauging of the measurements. In some cases, a beam and / or beam pair may be 1195 represented by a beam identity indication, e.g. a beam or beam pair number. Such an indication may be represented by one or more signalling sequences (e.g., a specific reference signalling sequences or sequences), which may be transmitted on the beam and / or beam pair, and / or a signalling characteristic and / or a resource / s used (e.g., time / frequency and / or code) and / or a specific RNTI (e.g., used for scrambling a CRC for some messages 1200 or transmissions) and / or by information provided in signalling, e.g. control signalling and / or system signalling, on the beam and / or beam pair, e.g. encoded and / or provided in an information held or as information element in some form of message of signalling, e.g. DCI and / or MAC and / or RRC signalling.

[0157] A reference beam may in general be one of a set of reference beams, the second set of 1205 reference beams being associated to the set of signalling beams. The sets being associated may refer to at least one beam of the first set being associated and / or corresponding to the second set (or vice versa), e.g. being based on it, for example by having the same analog or digital beamforming parameters and / or precoder and / or the same shape before analog beamforming, and / or being a modified form thereof, e.g. by performing additional analog 1210 beamforming. The set of signalling beams may be referred to as a first set of beams, a set of corresponding reference beams may be referred to as second set of beams.

[0158] In some variants, a reference beam and / or reference beams and / or reference signalling may correspond to and / or carry random access signalling, e.g. a random access preamble. Such a reference beam or signalling may be transmitted by another radio node. The signalling 1215 may indicate which beam is used for transmitting. Alternatively, the reference beams may be beams receiving the random access signalling. Random access signalling may be used for initial connection to the radio node and / or a cell provided by the radio node, and / or for reconnection. Utilising random access signalling facilitates quick and early beam selection.

[0159] The random access signalling may be on a random access channel, e.g. based on broadcast 1220 information provided by the radio node (the radio node performing the beam selection),

[0160] P111608W001 34 / 77 e.g. with synchronisation signalling (e.g., SSB block and / or associated thereto). The reference signalling may correspond to synchronisation signalling, e.g. transmitted by the radio node in a plurality of beams. The characteristics may be reported on by a node receiving the synchronisation signalling, e.g. in a random access process, e.g. a msg3 1225 for contention resolution, which may be transmitted on a physical uplink shared channel based on a resource allocation provided by the radio node.

[0161] A delay characteristic (which may correspond to delay spread information) and / or a measurement report may represent and / or indicate at least one of mean delay, and / or delay spread, and / or delay distribution, and / or delay spread distribution, and / or delay 1230 spread range, and / or relative delay spread, and / or energy (or power) distribution, and / or impulse response to received signalling, and / or the power delay profile of the received signals, and / or power delay profile related parameters of the received signal. A mean delay may represent the mean value and / or an averaged value of the delay spread, which may be weighted or unweighted. A distribution may be distribution over time / delay, e.g. 1235 of received power and / or energy of a signal. A range may indicate an interval of the delay spread distribution over time / delay, which may cover a predetermined percentage of the delay spread respective received energy or power, e.g. 50% or more, 75% or more, 90% or more, or 100%. A relative delay spread may indicate a relation to a threshold delay, e.g. of the mean delay, and / or a shift relative to an expected and / or configured timing, e.g. a 1240 timing at which the signalling would have been expected based on the scheduling, and / or a relation to a cyclic prefix duration (which may be considered on form of a threshold). Energy distribution or power distribution may pertain to the energy or power received over the time interval of the delay spread. A power delay profile may pertain to representations of the received signals, or the received signals energy / power, across time / delay. Power 1245 delay profile related parameters may pertain to metrics computed from the power delay profile. Different values and forms of delay spread information and / or report may be used, allowing a wide range of capabilities. The kind of information represented by a measurement report may be predefined, or be configured or configurable, e.g. with a measurement configuration and / or reference signalling configuration, in particular with 1250 higher layer signalling like RRC or MAC signalling and / or physical layer signalling like DCI signalling.

[0162] In general, different beam pair may differ in at least one beam; for example, a beam pair using a first received beam and a first transmission beam may be considered to be different from a second beam pair using the first received beam and a second transmission 1255 beam. A transmission beam using no precoding and / or beamforming, for example using the natural antenna profile, may be considered as a special form of transmission beam of a transmission beam pair. A beam may be indicated to a radio node by a transmitter

[0163] P111608W001 35 / 77 with a beam indication and / or a configuration, which for example may indicate beam parameters and / or time / frequency resources associated to the beam and / or a transmission 1260 mode and / or antenna profile and / or antenna port and / or precoder associated to the beam. Different beams may be provided with different content, for example different received beams may carry different signalling; however, there may be considered cases in which different beams carry the same signalling, for example the same data signalling and / or reference signalling. The beams may be transmitted by the same node and / or 1265 transmission point and / or antenna arrangement, or by different nodes and / or transmission points and / or antenna arrangements.

[0164] Communicating utilising a beam pair or a beam may comprise receiving signalling on a received beam (which may be a beam of a beam pair), and / or transmitting signalling on a beam, e.g. a beam of a beam pair. The following terms are to be interpreted from 1270 the point of view of the referred radio node: a received beam may be a beam carrying signalling received by the radio node (for reception, the radio node may use a reception beam, e.g. directed to the received beam, or be non-beamformed). A transmission beam may be a beam used by the radio node to transmit signalling. A beam pair may consist of a received beam and a transmission beam. The transmission beam and the received 1275 beam of a beam pair may be associated to each and / or correspond to each other, e.g. such that signalling on the received beam and signalling on a transmission beam travel essentially the same path (but in opposite directions), e.g. at least in a stationary or almost stationary condition. It should be noted that the terms “first” and “second” do not necessarily denote an order in time; a second signalling may be received and / or 1280 transmitted before, or in some cases simultaneous to, first signalling, or vice versa. The received beam and transmission beam of a beam pair may be on the same carrier or frequency range or bandwidth part, e.g. in a TDD operation; however, variants with FDD may be considered as well. Different beam pairs may operate on the same frequency ranges or carriers or bandwidth parts (e.g., such that transmission beams operate on 1285 the same frequency range or carriers or bandwidth part, and received beams on the same frequency range or carriers or bandwidth part (the transmission beam and received beams may be on the same or different ranges or carriers or BWPs). Communicating utilizing a first beam pair and / or first beam may be based on, and / or comprise, switching from the second beam pair or second beam to the first beam pair or first beam for communicating. 1290 The switching may be controlled by the network, for example a network node (which may be the source or transmitter of the received beam of the first beam pair and / or second beam pair, or be associated thereto, for example associated transmission points or nodes in dual connectivity). Such controlling may comprise transmitting control signalling, e.g. physical layer signalling and / or higher layer signalling. In some cases, the switching may 1295

[0165] P111608W001 36 / 77 be performed by the radio node without additional control signalling, for example based on measurements on signal quality and / or signal strength of beam pairs (e.g., of first and second received beams), in particular the first beam pair and / or the second beam pair. For example, it may be switched to the first beam pair (or first beam) if the signal quality or signal strength measured on the second beam pair (or second beam) is considered to 1300 be insufficient, and / or worse than corresponding measurements on the first beam pair indicate. Measurements performed on a beam pair (or beam) may in particular comprise measurements performed on a received beam of the beam pair. It may be considered that the timing indication may be determined before switching from the second beam pair to the first beam pair for communicating. Thus, the synchronization may be in place and / or 1305 the timing indication may be available for synchronising) when starting communication utilizing the first beam pair or first beam. However, in some cases the timing indication may be determined after switching to the first beam pair or first beam. This may be in particular useful if first signalling is expected to be received after the switching only, for example based on a periodicity or scheduled timing of suitable reference signalling 1310 on the first beam pair, e.g. first received beam. In general, a reception beam of a node may be associated to and / or correspond to a transmission beam of the node, e.g. such that the (spatial) angle of reception of the reception beam and the (spatial) angle of transmission of the transmission beam at least partially, or essentially or fully, overlap and / or coincide, in particular for TDD operation and / or independent of frequency. Spatial 1315 correspondence between beams may be considered in some cases, e.g. such that a beam pair (e.g., transmission beam of a transmitting node and reception beam of a receiving node) may be considered to comprise corresponding beams (e.g., the reception beam is suitable and / or the best beam to receive transmissions on the transmission beam, e.g. based on a threshold signal quality and / or signal strength and / or measurements); to each 1320 of such beams, there may be an associated or corresponding complementary beam of the respective node (e.g., to a transmission beam of a beam pair, there may be associated a reception beam of the transmitting node, and / or to the reception beam of a beam pair, there may be associated a transmitting beam of the receiving node; if the beams (e.g., at least essentially or substantially) overlap (e.g., in spatial angle), in some cases a beam 1325 pair may be considered to indicate four beams (or actually, two beam pairs).

[0166] In some cases, to one or more beams or signals or signallings may be associated a Quasi- CoLocation (QCL) characteristic or set of characteristics, or QCL class (also referred to as QCL type) or QCL identity; beams or signal or signallings sharing such may be considered to be Quasi-Colocated. Quasi-Colocated beams or signals or signallings may be 1330 considered (e.g., by a receiver) as the same beam or originating from the same transmitter or transmission source, at least in regard to the QCL characteristic or set or class or

[0167] P111608W001 37 / 77 identity, and / or to share the characteristic / s. QCL characteristics may pertain to propagation of signalling, and / or one or more delay characteristics, and / or pathloss, and / or signal quality, and / or signal strength, and / or beam direction, and / or beam shape (in 1335 particular, angle or area, e.g. area of coverage), and / or Doppler shift, and / or Doppler spread, and / or delay spread, and / or time synchronisation, and / or frequency synchronisation, and / or one or more other parameters, e.g. pertaining to a propagation channel and / or spatial RX param eter / s (which may refer to reception beam and / or transmission beam, e.g. shape or coverage or direction). A QCL characteristic may pertain to a spe1340 cific channel (e.g., physical layer channel like a control channel or data channel) and / or reference signalling type and / or antenna port. Different QCL classes or types may pertain to different QCL characteristics or sets of characteristics; a QCL class may define and / or pertain to one or more criteria and / or thresholds and / or ranges for one or more QCL characteristics beams have to fulfill to be considered Quasi-Colocated according to 1345 this class; a QCL identity may refer to and / or represent all beams being quasi-colocated, according to a QCL class. Different classes may pertain to one or more of the same characteristics (e.g., different classes may have different criteria and / or thresholds and / or ranges for one or more characteristics) and / or to different characteristics. A QCL indication may be seen as a form of beam indication, e.g. pertaining to all beams belonging 1350 to one QCL class and / or QCL identity and / or quasi-colocated beams. A QCL identity may be indicated by a QCL indication. In some cases, a beam, and / or a beam indication, may be considered to refer and / or represent a to a QCL identity, and / or to represent quasi-colocated beams or signals or signallings.

[0168] Transmission on multiple layers (multi-layer transmission) may refer to transmission of 1355 communication signalling and / or reference signalling simultaneously in one or more beams and / or using a plurality of transmission sources, e.g. controlled by one network node or one wireless device. The layers may refer to layers of transmission; a layer may be considered to represent one data or signalling stream. Different layers may carry different data and / or data streams, e.g., to increase data throughput. In some cases, the same 1360 data or data stream may be transported on different layers, e.g. to increase reliability. Multi-layer transmission may provide diversity, e.g. transmission diversity and / or spatial diversity. It may be considered that multi-layer transmission comprises 2, or more than 2 layers; the number of layers of transmission may be represented by a rank or rank indication. 1365

[0169] A transmission source may in particular comprise, and / or be represented by, and / or associated to, an antenna or group of antenna elements or antenna sub-array or antenna array or transmission point or TRP or TP (Transmission Point) or access point. In some cases, a transmission source may be represented or representable, and / or correspond

[0170] P111608W001 38 / 77 to, and / or associated to, an antenna port or layer of transmission, e.g. for multi-layer 1370 transmission. Different transmission sources may in particular comprise different and / or separately controllable antenna element / s or (sub-)arrays and / or be associated to different antenna ports. In particular, analog beamforming may be used, with separate analog control of the different transmission sources. An antenna port may indicate a transmission source, and / or a one or more transmission parameter, in particular of reference signalling 1375 associated to the antenna port. In particular, transmission parameters pertaining to, and / or indicating a frequency domain distribution or mapping (e.g., which comb to use and / or which subcarrier or frequency offset to use, or similar) of modulation symbols of the reference signalling, and / or to which cyclic shift to use (e.g., to shift elements of a modulation symbol sequence, or a root sequence, or a sequence based on or derived from 1380 the root sequence) and / or to which cover code to use (e.g., (e.g., to shift elements of a modulation symbol sequence, or a root sequence, or a sequence based on or derived from the root sequence). In some cases, a transmission source may represent a target for reception, e.g. if it is implemented as a TRP or AP (Access Point).

[0171] In some variants, reference signalling may be and / or comprise CSI-RS and / or PT-RS 1385 and / or DMRS, e.g. transmitted by the network node. In other variants, the reference signalling may be transmitted by a UE, e.g. to a network node or other UE, in which case it may comprise and / or be Sounding Reference signalling. Other, e.g. new, forms of reference signalling may be considered and / or used. In general, a modulation symbol of reference signalling respectively a resource element carrying it may be associated to a 1390 cyclic prefix.

[0172] Data signalling may be on a data channel, for example on a PDSCH or PSSCH, or on a dedicated data channel, e.g. for low latency and / or high reliability, e.g. a URLLC channel. Control signalling may be on a control channel, for example on a common control channel or a PDCCH or PSCCH, and / or comprise one or more DCI messages or SCI messages. 1395 Reference signalling may be associated to control signalling and / or data signalling, e.g. DM-RS and / or PT-RS.

[0173] Reference signalling, for example, may comprise DM-RS and / or pilot signalling and / or discovery signalling and / or synchronisation signalling and / or sounding signalling and / or phase tracking signalling and / or cell-specific reference signalling and / or user-specific sig- 1400 nailing, in particular CSI-RS. Reference signalling in general may be signalling with one or more signalling characteristics, in particular transmission power and / or sequence of modulation symbols and / or resource distribution and / or phase distribution known to the receiver. Thus, the receiver can use the reference signalling as a reference and / or for training and / or for compensation. The receiver can be informed about the reference signalling 1405

[0174] P111608W001 39 / 77 by the transmitter, e.g. being configured and / or signalling with control signalling, in particular physical layer signalling and / or higher layer signalling (e.g., DCI and / or RRC signalling), and / or may determine the corresponding information itself, e.g. a network node configuring a UE to transmit reference signalling. Reference signalling may be signalling comprising one or more reference symbols and / or structures. Reference signalling may 1410 be adapted for gauging and / or estimating and / or representing transmission conditions, e.g. channel conditions and / or transmission path conditions and / or channel (or signal or transmission) quality. It may be considered that the transmission characteristics (e.g., signal strength and / or form and / or modulation and / or timing) of reference signalling are available for both transmitter and receiver of the signalling (e.g., due to being prede- 1415 fined and / or configured or configurable and / or being communicated). Different types of reference signalling may be considered, e.g. pertaining to uplink, downlink or sidelink, cell-specific (in particular, cell- wide, e.g., CRS) or device or user specific (addressed to a specific target or user equipment, e.g., CSI-RS), demodulation-related (e.g., DMRS) and / or signal strength related, e.g. power-related or energy-related or amplitude-related 1420 (e.g., SRS or pilot signalling) and / or phase-related, etc.

[0175] References to specific resource structures like an allocation unit and / or block symbol and / or block symbol group and / or transmission timing structure and / or symbol and / or slot and / or mini-slot and / or subcarrier and / or carrier may pertain to a specific numerology, which may be predefined and / or configured or configurable. A transmission timing 1425 structure may represent a time interval, which may cover one or more symbols. Some examples of a transmission timing structure are transmission time interval (TTI), subframe, slot and mini-slot. A slot may comprise a predetermined, e.g. predefined and / or configured or configurable, number of symbols, e.g. 6 or 7, or 12 or 14. A mini-slot may comprise a number of symbols (which may in particular be configurable or configured) 1430 smaller than the number of symbols of a slot, in particular 1, 2, 3 or 4, or more symbols, e.g. less symbols than symbols in a slot. A transmission timing structure may cover a time interval of a specific length, which may be dependent on symbol time length and / or cyclic prefix used. A transmission timing structure may pertain to, and / or cover, a specific time interval in a time stream, e.g. synchronized for communication. Timing structures 1435 used and / or scheduled for transmission, e.g. slot and / or mini-slots, may be scheduled in relation to, and / or synchronized to, a timing structure provided and / or defined by other transmission timing structures. Such transmission timing structures may define a timing grid, e.g., with symbol time intervals within individual structures representing the smallest timing units. Such a timing grid may for example be defined by slots or subframes 1440 (wherein in some cases, subframes may be considered specific variants of slots). A transmission timing structure may have a duration (length in time) determined based on the

[0176] P111608W001 40 / 77 durations of its symbols, possibly in addition to cyclic prefix / es used. The symbols of a transmission timing structure may have the same duration, or may in some variants have different duration. The number of symbols in a transmission timing structure may be 1445 predefined and / or configured or configurable, and / or be dependent on numerology. The timing of a mini-slot may generally be configured or configurable, in particular by the network and / or a network node. The timing may be configurable to start and / or end at any symbol of the transmission timing structure, in particular one or more slots.

[0177] A transmission quality parameter may in general correspond to the number R of retrans- 1450 missions and / or number T of total transmissions, and / or coding (e.g., number of coding bits, e.g. for error detection coding and / or error correction coding like FEC coding) and / or code rate and / or BLER and / or BER requirements and / or transmission power level (e.g., minimum level and / or target level and / or base power level P0 and / or transmission power control command, TPC, step size) and / or signal quality, e.g. SNR and / or 1455 SIR and / or SINR and / or power density and / or energy density.

[0178] A buffer state report (or buffer status report, BSR) may comprise information representing the presence and / or size of data to be transmitted (e.g., available in one or more buffers, for example provided by higher layers). The size may be indicated explicitly, and / or indexed to range / s of sizes, and / or may pertain to one or more different channel / s 1460 and / or acknowledgement processes and / or higher layers and / or channel groups / s, e.g, one or more logical channel / s and / or transport channel / s and / or groups thereof: The structure of a BSR may be predefined and / or configurable of configured, e.g. to override and / or amend a predefined structure, for example with higher layer signalling, e.g. RRC signalling. There may be different forms of BSR with different levels of resolution and / or 1465 information, e.g. a more detailed long BSR and a less detailed short BSR. A short BSR may concatenate and / or combine information of a long BSR, e.g. providing sums for data available for one or more channels and / or or channels groups and / or buffers, which might be represented individually in a long BSR; and / or may index a less-detailed range scheme for data available or buffered. A BSR may be used in lieu of a scheduling request, e.g. 1470 by a network node scheduling or allocating (uplink) resources for the transmitting radio node like a wireless device or UE or IAB node.

[0179] There is generally considered a program product comprising instructions adapted for causing processing and / or control circuitry to carry out and / or control any method described herein, in particular when executed on the processing and / or control circuitry. Also, there 1475 is considered a carrier medium arrangement carrying and / or storing a program product as described herein.

[0180] A carrier medium arrangement may comprise one or more carrier media. Generally, a

[0181] P111608W001 41 / 77 carrier medium may be accessible and / or readable and / or receivable by processing or control circuitry. Storing data and / or a program product and / or code may be seen 1480 as part of carrying data and / or a program product and / or code. A carrier medium generally may comprise a guiding / transporting medium and / or a storage medium. A guiding / transporting medium may be adapted to carry and / or carry and / or store signals, in particular electromagnetic signals and / or electrical signals and / or magnetic signals and / or optical signals. A carrier medium, in particular a guiding / transporting medium, 1485 may be adapted to guide such signals to carry them. A carrier medium, in particular a guiding / transporting medium, may comprise the electromagnetic held, e.g. radio waves or microwaves, and / or optically transmissive material, e.g. glass fiber, and / or cable. A storage medium may comprise at least one of a memory, which may be volatile or nonvolatile, a buffer, a cache, an optical disc, magnetic memory, Hash memory, etc. 1490

[0182] A system comprising one or more radio nodes as described herein, in particular a network node and a user equipment, is described. The system may be a wireless communication system, and / or provide and / or represent a radio access network.

[0183] Moreover, there may be generally considered a method of operating an information system, the method comprising providing information. Alternatively, or additionally, an 1495 information system adapted for providing information may be considered. Providing information may comprise providing information for, and / or to, a target system, which may comprise and / or be implemented as radio access network and / or a radio node, in particular a network node or user equipment or terminal. Providing information may comprise transferring and / or streaming and / or sending and / or passing on the informa- 1500 tion, and / or offering the information for such and / or for download, and / or triggering such providing, e.g. by triggering a different system or node to stream and / or transfer and / or send and / or pass on the information. The information system may comprise, and / or be connected or connectable to, a target, for example via one or more intermediate systems, e.g. a core network and / or internet and / or private or local network. Information may be 1505 provided utilising and / or via such intermediate system / s. Providing information may be for radio transmission and / or for transmission via an air interface and / or utilising a RAN or radio node as described herein. Connecting the information system to a target, and / or providing information, may be based on a target indication, and / or adaptive to a target indication. A target indication may indicate the target, and / or one or more parameters of 1510 transmission pertaining to the target and / or the paths or connections over which the information is provided to the target. Such parameter / s may in particular pertain to the air interface and / or radio access network and / or radio node and / or network node. Example parameters may indicate for example type and / or nature of the target, and / or transmission capacity (e.g., data rate) and / or latency and / or reliability and / or cost, respectively 1515

[0184] P111608W001 42 / 77 one or more estimates thereof. The target indication may be provided by the target, or determined by the information system, e.g. based on information received from the target and / or historical information, and / or be provided by a user, for example a user operating the target or a device in communication with the target, e.g. via the RAN and / or air interface. For example, a user may indicate on a user equipment communicating with 1520 the information system that information is to be provided via a RAN, e.g. by selecting from a selection provided by the information system, for example on a user application or user interface, which may be a web interface. An information system may comprise one or more information nodes. An information node may generally comprise processing circuitry and / or communication circuitry. In particular, an information system and / or an 1525 information node may be implemented as a computer and / or a computer arrangement, e.g. a host computer or host computer arrangement and / or server or server arrangement.

[0185] In some variants, an interaction server (e.g., web server) of the information system may provide a user interface, and based on user input may trigger transmitting and / or streaming information provision to the user (and / or the target) from another server, which may 1530 be connected or connectable to the interaction server and / or be part of the information system or be connected or connectable thereto. The information may be any kind of data, in particular data intended for a user of for use at a terminal, e.g. video data and / or audio data and / or location data and / or interactive data and / or game-related data and / or environmental data and / or technical data and / or traffic data and / or vehicular data and / or 1535 circumstantial data and / or operational data. The information provided by the information system may be mapped to, and / or mappable to, and / or be intended for mapping to, communication or data signalling and / or one or more data channels as described herein (which may be signalling or channel / s of an air interface and / or used within a RAN and / or for radio transmission). It may be considered that the information is formatted 1540 based on the target indication and / or target, e.g. regarding data amount and / or data rate and / or data structure and / or timing, which in particular may be pertaining to a mapping to communication or data signalling and / or a data channel. Mapping information to data signalling and / or data channel / s may be considered to refer to using the signalling / channel / s to carry the data, e.g. on higher layers of communication, with the 1545 signalling / channel / s underlying the transmission. A target indication generally may comprise different components, which may have different sources, and / or which may indicate different characteristics of the target and / or communication path / s thereto. A format of information may be specifically selected, e.g. from a set of different formats, for information to be transmitted on an air interface and / or by a RAN as described herein. This may 1550 be particularly pertinent since an air interface may be limited in terms of capacity and / or of predictability, and / or potentially be cost sensitive. The format may be selected to be adapted to the transmission indication, which may in particular indicate that a RAN or

[0186] P111608W001 43 / 77 radio node as described herein is in the path (which may be the indicated and / or planned and / or expected path) of information between the target and the information system. A 1555 (communication) path of information may represent the interface / s (e.g., air and / or cable interfaces) and / or the intermediate system / s (if any), between the information system and / or the node providing or transferring the information, and the target, over which the information is, or is to be, passed on. A path may be (at least partly) undetermined when a target indication is provided, and / or the information is provided / transferred by 1560 the information system, e.g. if an internet is involved, which may comprise multiple, dynamically chosen paths. Information and / or a format used for information may be packet-based, and / or be mapped, and / or be mappable and / or be intended for mapping, to packets. Alternatively, or additionally, there may be considered a method for operating a target device comprising providing a target indicating to an information system. 1565 More alternatively, or additionally, a target device may be considered, the target device being adapted for providing a target indication to an information system. In another approach, there may be considered a target indication tool adapted for, and / or comprising an indication module for, providing a target indication to an information system. The target device may generally be a target as described above. A target indication tool may 1570 comprise, and / or be implemented as, software and / or application or app, and / or web interface or user interface, and / or may comprise one or more modules for implementing actions performed and / or controlled by the tool. The tool and / or target device may be adapted for, and / or the method may comprise, receiving a user input, based on which a target indicating may be determined and / or provided. Alternatively, or additionally, the 1575 tool and / or target device may be adapted for, and / or the method may comprise, receiving information and / or communication signalling carrying information, and / or operating on, and / or presenting (e.g., on a screen and / or as audio or as other form of indication), information. The information may be based on received information and / or communication signalling carrying information. Presenting information may comprise processing received 1580 information, e.g. decoding and / or transforming, in particular between different formats, and / or for hardware used for presenting. Operating on information may be independent of or without presenting, and / or proceed or succeed presenting, and / or may be without user interaction or even user reception, for example for automatic processes, or target devices without (e.g., regular) user interaction like MTC devices, of for automotive or transport 1585 or industrial use. The information or communication signalling may be expected and / or received based on the target indication. Presenting and / or operating on information may generally comprise one or more processing steps, in particular decoding and / or executing and / or interpreting and / or transforming information. Operating on information may generally comprise relaying and / or transmitting the information, e.g. on an air interface, 1590 which may include mapping the information onto signalling (such mapping may generally

[0187] P111608W001 44 / 77 pertain to one or more layers, e.g. one or more layers of an air interface, e.g. RLC (Radio Link Control) layer and / or MAC layer and / or physical layer / s). The information may be imprinted (or mapped) on communication signalling based on the target indication, which may make it particularly suitable for use in a RAN (e.g., for a target device like a network 1595 node or in particular a UE or terminal). The tool may generally be adapted for use on a target device, like a UE or terminal. Generally, the tool may provide multiple functionalities, e.g. for providing and / or selecting the target indication, and / or presenting, e.g. video and / or audio, and / or operating on and / or storing received information. Providing a target indication may comprise transmitting or transferring the indication as signalling, 1600 and / or carried on signalling, in a RAN, for example if the target device is a UE, or the tool for a UE. It should be noted that such provided information may be transferred to the information system via one or more additionally communication interfaces and / or paths and / or connections. The target indication may be a higher-layer indication and / or the information provided by the information system may be higher-layer information, e.g. 1605 application layer or user-layer, in particular above radio layers like transport layer and physical layer. The target indication may be mapped on physical layer radio signalling, e.g. related to or on the user-plane, and / or the information may be mapped on physical layer radio communication signalling, e.g. related to or on the user-plane (in particular, in reverse communication directions). The described approaches allow a target indication 1610 to be provided, facilitating information to be provided in a specific format particularly suitable and / or adapted to efficiently use an air interface. A user input may for example represent a selection from a plurality of possible transmission modes or formats, and / or paths, e.g. in terms of data rate and / or packaging and / or size of information to be provided by the information system. 1615

[0188] In general, a numerology and / or subcarrier spacing may indicate the bandwidth (in frequency domain) of a subcarrier of a carrier, and / or the number of subcarriers in a carrier and / or the numbering of the subcarriers in a carrier, and / or the symbol time length. Different numerologies may in particular be different in the bandwidth of a subcarrier.

[0189] In some variants, all the subcarriers in a carrier have the same bandwidth associated 1620 to them. The numerology and / or subcarrier spacing may be different between carriers in particular regarding the subcarrier bandwidth. A symbol time length, and / or a time length of a timing structure pertaining to a carrier may be dependent on the carrier frequency, and / or the subcarrier spacing and / or the numerology. In particular, different numerologies may have different symbol time lengths, even on the same carrier. 1625

[0190] Signalling may generally comprise one or more (e.g., modulation) symbols and / or signals and / or messages. A signal may comprise or represent one or more bits. An indication may represent signalling, and / or be implemented as a signal, or as a plurality of signals. One or

[0191] P111608W001 45 / 77 more signals may be included in and / or represented by a message, signalling, in particular control signalling, may comprise a plurality of signals and / or messages, which may be 1630 transmitted on different carriers and / or be associated to different signalling processes, e.g. representing and / or pertaining to one or more such processes and / or corresponding information. An indication may comprise signalling, and / or a plurality of signals and / or messages and / or may be comprised therein, which may be transmitted on different carriers and / or be associated to different acknowledgement signalling processes, e.g. representing 1635 and / or pertaining to one or more such processes. Signalling associated to a channel may be transmitted such that represents signalling and / or information for that channel, and / or that the signalling is interpreted by the transmitter and / or receiver to belong to that channel. Such signalling may generally comply with transmission parameters and / or format / s for the channel. 1640

[0192] An antenna arrangement may comprise one or more antenna elements (radiating elements), which may be combined in antenna arrays. An antenna array or sub-array may comprise one antenna element, or a plurality of antenna elements, which may be arranged e.g. two dimensionally (for example, a panel) or three dimensionally. It may be considered that each antenna array or sub-array or element is separately controllable, respectively 1645 that different antenna arrays are controllable separately from each other. A single antenna element / radiator may be considered the smallest example of a sub-array. Examples of antenna arrays comprise one or more multi-antenna panels or one or more individually controllable antenna elements. An antenna arrangement may comprise a plurality of antenna arrays. It may be considered that an antenna arrangement is associated to 1650 a (specific and / or single) radio node, e.g. a configuring or informing or scheduling radio node, e.g. to be controlled or controllable by the radio node. An antenna arrangement associated to a UE or terminal may be smaller (e.g., in size and / or number of antenna elements or arrays) than the antenna arrangement associated to a network node. Antenna elements of an antenna arrangement may be configurable for different arrays, e.g. 1655 to change the beamforming characteristics. In particular, antenna arrays may be formed by combining one or more independently or separately controllable antenna elements or sub-arrays. The beams may be provided by analog beamforming, or in some variants by digital beamforming, or by hybrid beamforming combing analog and digital beamforming.

[0193] The informing radio nodes may be configured with the manner of beam transmission, e.g. 1660 by transmitting a corresponding indicator or indication, for example as beam identify indication. However, there may be considered cases in which the informing radio node / s are not configured with such information, and / or operate transparently, not knowing the way of beamforming used. An antenna arrangement may be considered separately controllable in regard to the phase and / or amplitude / power and / or gain of a signal feed to it for 1665

[0194] P111608W001 46 / 77 transmission, and / or separately controllable antenna arrangements may comprise an independent or separate transmit and / or receive unit and / or ADC (analog- Digit al- Converter, alternatively an ADC chain) or DCA (Digital-to-analog Converter, alternatively a DCA chain) to convert digital control information into an analog antenna feed for the whole antenna arrangement (the ADC / DCA may be considered part of, and / or connected or 1670 connectable to, antenna circuitry) or vice versa. A scenario in which an ADC or DCA is controlled directly for beamforming may be considered an analog beamforming scenario; such controlling may be performed after encoding / decoding and7or after modulation symbols have been mapped to resource elements. This may be on the level of antenna arrangements using the same ADC / DCA, e.g. one antenna element or a group of antenna 1675 elements associated to the same ADC / DCA. Digital beamforming may correspond to a scenario in which processing for beamforming is provided before feeding signalling to the ADC / DCA, e.g. by using one or more precoder / s and / or by precoding information, for example before and / or when mapping modulation symbols to resource elements. Such a precoder for beamforming may provide weights, e.g. for amplitude and / or phase, and / or 1680 may be based on a (precoder) codebook, e.g. selected from a codebook. A precoder may pertain to one beam or more beams, e.g. defining the beam or beams. The codebook may be configured or configurable, and / or be predefined. DFT beamforming may be considered a form of digital beamforming, wherein a DFT procedure is used to form one or more beams. Hybrid forms of beamforming may be considered. 1685

[0195] A beam may be defined by a spatial and / or angular and / or spatial angular distribution of radiation and / or a spatial angle (also referred to as solid angle) or spatial (solid) angle distribution into which radiation is transmitted (for transmission beamforming) or from which it is received (for reception beamforming). Reception beamforming may comprise only accepting signals coming in from a reception beam (e.g., using analog beamforming 1690 to not receive outside reception beam / s), and / or sorting out signals that do not come in in a reception beam, e.g. in digital postprocessing, e.g. digital beamforming. A beam may have a solid angle equal to or smaller than 4*pi sr (4*pi correspond to a beam covering all directions), in particular smaller than 2* pi, or pi, or pi / 2, or pi / 4 or pi / 8 or pi / 16. In particular for high frequencies, smaller beams may be used. Different 1695 beams may have different directions and / or sizes (e.g., solid angle and / or reach). A beam may have a main direction, which may be defined by a main lobe (e.g., center of the main lobe, e.g. pertaining to signal strength and / or solid angle, which may be averaged and / or weighted to determine the direction), and may have one or more sidelobes. A lobe may generally be defined to have a continuous or contiguous distribution of energy and / or 1700 power transmitted and / or received, e.g. bounded by one or more contiguous or contiguous regions of zero energy (or practically zero energy). A main lobe may comprise the lobe

[0196] P111608W001 47 / 77 with the largest signal strength and / or energy and / or power content. However, sidelobes usually appear due to limitations of beamforming, some of which may carry signals with significant strength, and may cause multi-path effects. A sidelobe may generally have a 1705 different direction than a main lobe and / or other side lobes, however, due to reflections a sidelobe still may contribute to transmitted and / or received energy or power. A beam may be swept and / or switched over time, e.g., such that its (main) direction is changed, but its shape (angular / solid angle distribution) around the main direction is not changed, e.g. from the transmitter’s views for a transmission beam, or the receiver’s view for a 1710 reception beam, respectively. Sweeping may correspond to continuous or near continuous change of main direction (e.g., such that after each change, the main lobe from before the change covers at least partly the main lobe after the change, e.g. at least to 50 or 75 or 90 percent). Switching may correspond to switching direction non-continuously, e.g. such that after each change, the main lobe from before the change does not cover the main 1715 lobe after the change, e.g. at most to 50 or 25 or 10 percent.

[0197] Signal strength may be a representation of signal power and / or signal energy, e.g. as seen from a transmitting node or a receiving node. A beam with larger strength at transmission (e.g., according to the beamforming used) than another beam does may not necessarily have larger strength at the receiver, and vice versa, for example due to 1720 interference and / or obstruction and / or dispersion and / or absorption and / or reflection and / or attrition or other effects influencing a beam or the signalling it carries. Signal quality may in general be a representation of how well a signal may be received over noise and / or interference. A beam with better signal quality than another beam does not necessarily have a larger beam strength than the other beam. Signal quality may be 1725 represented for example by SIR, SNR, SINR, BER, BLER, Energy per resource element over noise / interference or another corresponding quality measure. Signal quality and / or signal strength may pertain to, and / or may be measured with respect to, a beam, and / or specific signalling carried by the beam, e.g. reference signalling and / or a specific channel, e.g. a data channel or control channel. Signal strength may be represented by received 1730 signal strength, and / or relative signal strength, e.g. in comparison to a reference signal (strength).

[0198] Uplink or sidelink signalling may be OFDMA (Orthogonal Frequency Division Multiple Access) or SC-FDMA (Single Carrier Frequency Division Multiple Access) signalling. Downlink signalling may in particular be OFDMA signalling. However, signalling like 1735 communication signalling and / or sensing signalling is not limited thereto (Filter-Bank based signalling and / or Single- Carrier based signalling, e.g. SC-FDE signalling, may be considered alternatives).

[0199] P111608W001 48 / 77 A radio node may generally be considered a device or node adapted for wireless and / or radio (and / or millimeter wave) frequency communication, and / or for communication util- 1740 ising an air interface, e.g. according to a communication standard.

[0200] A radio node may be a network node, or a user equipment or terminal. A network node may be any radio node of a wireless communication network, e.g. a base station and / or gNodeB (gNB) and / or eNodeB (eNB) and / or relay node and / or micro / nano / pico / femto node and / or transmission point (TP) and / or access point (AP) and / or other node, in 1745 particular for a RAN or other wireless communication network as described herein.

[0201] The terms user equipment (UE) and terminal may be considered to be interchangeable in the context of this disclosure. A wireless device, user equipment or terminal may represent an end device for communication utilising the wireless communication network, and / or be implemented as a user equipment according to a standard. Examples of user 1750 equipments may comprise a phone like a smartphone, a personal communication device, a mobile phone or terminal, a computer, in particular laptop, a sensor or machine with radio capability (and / or adapted for the air interface), in particular for MTC (Machine-Type- Communication, sometimes also referred to M2M, Machine- To-Machine), or a vehicle adapted for wireless communication. A user equipment or terminal may be mobile or sta- 1755 tionary. A wireless device generally may comprise, and / or be implemented as, processing circuitry and / or radio circuitry, which may comprise one or more chips or sets of chips.

[0202] The circuitry and / or circuitries may be packaged, e.g. in a chip housing, and / or may have one or more physical interfaces to interact with other circuitry and / or for power supply. Such a wireless device may be intended for use in a user equipment or terminal. 1760

[0203] A radio node may generally comprise processing circuitry and / or radio circuitry. A radio node, in particular a network node, may in some cases comprise cable circuitry and / or communication circuitry, with which it may be connected or connectable to another radio node and / or a core network.

[0204] Circuitry may comprise integrated circuitry. Processing circuitry may comprise one or 1765 more processors and / or controllers (e.g., microcontrollers), and / or ASICs (Application Specific Integrated Circuitry) and / or FPGAs (Field Programmable Gate Array), or similar. It may be considered that processing circuitry comprises, and / or is (operatively) connected or connectable to one or more memories or memory arrangements. A memory arrangement may comprise one or more memories. A memory may be adapted 1770 to store digital information. Examples for memories comprise volatile and non-volatile memory, and / or Random Access Memory (RAM), and / or Read-Only-Memory (ROM), and / or magnetic and / or optical memory, and / or flash memory, and / or hard disk memory, and / or EPROM or EEPROM (Erasable Programmable ROM or Electrically Erasable

[0205] P111608W001 49 / 77 Programmable ROM). 1775

[0206] Radio circuitry may comprise one or more transmitters and / or receivers and / or transceivers (a transceiver may operate or be operable as transmitter and receiver, and / or may comprise joint or separated circuitry for receiving and transmitting, e.g. in one package or housing), and / or may comprise one or more amplifiers and / or oscillators and / or filters, and / or may comprise, and / or be connected or connectable to antenna circuitry and / or 1780 one or more antennas and / or antenna arrays. An antenna array may comprise one or more antennas, which may be arranged in a dimensional array, e.g. 2D or 3D array, and / or antenna panels. A remote radio head (RRH) may be considered as an example of an antenna array. However, in some variants, an RRH may be also be implemented as a network node, depending on the kind of circuitry and / or functionality implemented 1785 therein.

[0207] Communication circuitry may comprise radio circuitry and / or cable circuitry. Communication circuitry generally may comprise one or more interfaces, which may be air inter- face / s and / or cable interface / s and / or optical interface / s, e.g. laser-based. Interface / s may be in particular packet-based. Cable circuitry and / or a cable interfaces may com- 1790 prise, and / or be connected or connectable to, one or more cables (e.g., optical fiber-based and / or wire-based), which may be directly or indirectly (e.g., via one or more intermediate systems and / or interfaces) be connected or connectable to a target, e.g. controlled by communication circuitry and / or processing circuitry.

[0208] Any one or all of the modules disclosed herein may be implemented in software and / or 1795 firmware and / or hardware. Different modules may be associated to different components of a radio node, e.g. different circuitries or different parts of a circuitry. It may be considered that a module is distributed over different components and / or circuitries. A program product as described herein may comprise the modules related to a device on which the program product is intended (e.g., a user equipment or network node) to be executed (the 1800 execution may be performed on, and / or controlled by the associated circuitry).

[0209] A wireless communication network may be or comprise a radio access network and / or a backhaul network (e.g. a relay or backhaul network or an IAB network), and / or a Radio Access Network (RAN) in particular according to a communication standard. A communication standard may in particular a standard according to 3GPP and / or 5G, 1805 e.g. according to NR or LTE, in particular LTE Evolution.

[0210] A wireless communication network may be and / or comprise a Radio Access Network (RAN), which may be and / or comprise any kind of cellular and / or wireless radio network, which may be connected or connectable to a core network. The approaches de-

[0211] P111608W001 50 / 77 scribed herein are particularly suitable for a 5G network, e.g. LTE Evolution and / or NR 1810 (New Radio), respectively successors thereof. A RAN may comprise one or more network nodes, and / or one or more terminals, and / or one or more radio nodes. A network node may in particular be a radio node adapted for radio and / or wireless and / or cellular communication with one or more terminals. A terminal may be any device adapted for radio and / or wireless and / or cellular communication with or within a RAN, e.g. a user 1815 equipment (UE) or mobile phone or smartphone or computing device or vehicular communication device or device for machine- type-communication (MTC), etc. A terminal may be mobile, or in some cases stationary. A RAN or a wireless communication network may comprise at least one network node and a UE, or at least two radio nodes. There may be generally considered a wireless communication network or system, e.g. a RAN or 1820 RAN system, comprising at least one radio node, and / or at least one network node and at least one terminal.

[0212] Transmitting in downlink may pertain to transmission from the network or network node to the terminal. Transmitting in uplink may pertain to transmission from the terminal to the network or network node. Transmitting in sidelink may pertain to (direct) 1825 transmission from one terminal to another. Uplink, downlink and sidelink (e.g., sidelink transmission and reception) may be considered communication directions. In some variants, uplink and downlink may also be used to described wireless communication between network nodes, e.g. for wireless backhaul and / or relay communication and / or (wireless) network communication for example between base stations or similar network nodes, in 1830 particular communication terminating at such. It may be considered that backhaul and / or relay communication and / or network communication is implemented as a form of sidelink or uplink communication or similar thereto.

[0213] Control information or a control information message or corresponding signalling (control signalling) may be transmitted on a control channel, e.g. a physical control channel, 1835 which may be a downlink channel or (or a sidelink channel in some cases, e.g. one UE scheduling another UE). For example, control information / allocation information may be signaled by a network node on PDCCH (Physical Downlink Control Channel) and / or a PDSCH (Physical Downlink Shared Channel) and / or a HARQ-specihc channel. Acknowledgement signalling, e.g. as a form of control information or signalling like uplink 1840 control information / signalling, may be transmitted by a terminal on a PUCCH (Physical Uplink Control Channel) and / or PUSCH (Physical Uplink Shared Channel) and / or a HARQ-specihc channel. Multiple channels may apply for multi-component / multi-carrier indication or signalling.

[0214] Transmitting acknowledgement signalling may in general be based on and / or in response 1845

[0215] P111608W001 51 / 77 to subject transmission, and / or to control signalling scheduling subject transmission. Such control signalling and / or subject signalling may be transmitted by a signalling radio node (which may be a network node, and / or a node associated to it, e.g. in a dual connectivity scenario. Subject transmission and / or subject signalling may be transmission or signalling to which ACK / NACK or acknowledgement information pertains, e.g. 1850 indicating correct or incorrect reception and / or decoding of the subject transmission or signalling. Subject signalling or transmission may in particular comprise and / or be represented by data signalling, e.g. on a PDSCH or PSSCH, or some forms of control signalling, e.g. on a PDCCH or PSSCH, for example for specific formats.

[0216] A signalling characteristic may be based on a type or format of a scheduling grant and / or 1855 scheduling assignment, and / or type of allocation, and / or timing of acknowledgement signalling and / or the scheduling grant and / or scheduling assignment, and / or resources associated to acknowledgement signalling and / or the scheduling grant and / or scheduling assignment. For example, if a specific format for a scheduling grant (scheduling or allocating the allocated resources) or scheduling assignment (scheduling the subject 1860 transmission for acknowledgement signalling) is used or detected, the first or second communication resource may be used. Type of allocation may pertain to dynamic allocation (e.g., using DCI / PDCCH) or semi-static allocation (e.g., for a configured grant). Timing of acknowledgement signalling may pertain to a slot and / or symbol / s the signalling is to be transmitted. Resources used for acknowledgement signalling may pertain to the allo1865 cated resources. Timing and / or resources associated to a scheduling grant or assignment may represent a search space or CORESET (a set of resources configured for reception of PDCCH transmissions) in which the grant or assignment is received. Thus, which transmission resource to be used may be based on implicit conditions, requiring low signalling overhead. 1870

[0217] Scheduling may comprise indicating, e.g. with control signalling like DCI or SCI signalling and / or signalling on a control channel like PDCCH or PSCCH, one or more scheduling opportunities of a configuration intended to carry data signalling or subject signalling. The configuration may be represented or representable by, and / or correspond to, a table. A scheduling assignment may for example point to an opportunity of the reception allo1875 cation configuration, e.g. indexing a table of scheduling opportunities. In some cases, a reception allocation configuration may comprise 15 or 16 scheduling opportunities. The configuration may in particular represent allocation in time. It may be considered that the reception allocation configuration pertains to data signalling, in particular on a physical data channel like PDSCH or PSSCH. In general, the reception allocation configuration 1880 may pertain to downlink signalling, or in some scenarios to sidelink signalling. Control signalling scheduling subject transmission like data signalling may point and / or index

[0218] P111608W001 52 / 77 and / or refer to and / or indicate a scheduling opportunity of the reception allocation configuration. It may be considered that the reception allocation configuration is configured or configurable with higher-layer signalling, e.g. RRC or MAC layer signalling. The recep- 1885 tion allocation configuration may be applied and / or applicable and / or valid for a plurality of transmission timing intervals, e.g. such that for each interval, one or more opportunities may be indicated or allocated for data signalling. These approaches allow efficient and flexible scheduling, which may be semi-static, but may updated or reconfigured on useful timescales in response to changes of operation conditions. 1890

[0219] Control information, e.g., in a control information message, in this context may in particular be implemented as and / or represented by a scheduling assignment, which may indicate subject transmission for feedback (transmission of acknowledgement signalling), and / or reporting timing and / or frequency resources and / or code resources. Reporting timing may indicate a timing for scheduled acknowledgement signalling, e.g. slot and / or 1895 symbol and / or resource set. Control information may be carried by control signalling.

[0220] Subject transmissions may comprise one or more individual transmissions. Scheduling assignments may comprise one or more scheduling assignments. It should generally be noted that in a distributed system, subject transmissions, configuration and / or scheduling may be provided by different nodes or devices or transmission points. Different subject trans- 1900 missions may be on the same carrier or different carriers (e.g., in a carrier aggregation), and / or same or different bandwidth parts, and / or on the same or different layers or beams, e.g. in a MIMO scenario, and / or to same or different ports. Generally, subject transmissions may pertain to different HARQ or ARQ processes (or different sub-processes, e.g. in MIMO with different beams / layers associated to the same process identifier, but different 1905 sub-process-identifiers like swap bits). A scheduling assignment and / or a HARQ codebook may indicate a target HARQ structure. A target HARQ structure may for example indicate an intended HARQ response to a subject transmission, e.g. the number of bits and / or whether to provide code block group level response or not. However, it should be noted that the actual structure used may differ from the target structure, e.g. due to the 1910 total size of target structures for a subpattern being larger than the predetermined size.

[0221] Transmitting acknowledgement signalling, also referred to as transmitting acknowledgement information or feedback information or simply as ARQ or HARQ feedback or feedback or reporting feedback, may comprise, and / or be based on determining correct or incorrect reception of subject transmission / s, e.g. based on error coding and / or based on 1915 scheduling assignment / s scheduling the subject transmissions. Transmitting acknowledgement information may be based on, and / or comprise, a structure for acknowledgement information to transmit, e.g. the structure of one or more subpatterns, e.g. based on

[0222] P111608W001 53 / 77 which subject transmission is scheduled for an associated subdivision. Transmitting acknowledgement information may comprise transmitting corresponding signalling, e.g. at 1920 one instance and / or in one message and / or one channel, in particular a physical channel, which may be a control channel. In some cases, the channel may be a shared channel or data channel, e.g. utilising rate-matching of the acknowledgment information. The acknowledgement information may generally pertain to a plurality of subject transmissions, which may be on different channels and / or carriers, and / or may comprise data 1925 signalling and / or control signalling. The acknowledgment information may be based on a codebook, which may be based on one or more size indications and / or assignment indications (representing HARQ structures), which may be received with a plurality of control signallings and / or control messages, e.g. in the same or different transmission timing structures, and / or in the same or different (target) sets of resources. Transmitting 1930 acknowledgement information may comprise determining the codebook, e.g. based on control information in one or more control information messages and / or a configuration. A codebook may pertain to transmitting acknowledgement information at a single and / or specific instant, e.g. a single PUCCH or PUSCH transmission, and / or in one message or with jointly encoded and / or modulated acknowledgement information. Generally, ac- 1935 knowledgment information may be transmitted together with other control information, e.g. a scheduling request and / or measurement information.

[0223] Acknowledgement signalling may in some cases comprise, next to acknowledgement information, other information, e.g. control information, in particular, uplink or sidelink control information, like a scheduling request and / or measurement information, or sim- 1940 ilar, and / or error detection and / or correction information, respectively associated bits. The payload size of acknowledgement signalling may represent the number of bits of acknowledgement information, and / or in some cases the total number of bits carried by the acknowledgement signalling, and / or the number of resource elements needed. Acknowledgement signalling and / or information may pertain to ARQ and / or HARQ pro- 1945 cesses; an ARQ process may provide ACK / NACK (and perhaps additional feedback) feedback, and decoding may be performed on each (re-)transmission separately, without soft-buffering / soft-combining intermediate data, whereas HARQ may comprise soft- buffering / soft-combining of intermediate data of decoding for one or more (re-)transmissions.

[0224] Subject transmission may be data signalling or control signalling. The transmission may 1950 be on a shared or dedicated channel. Data signalling may be on a data channel, for example on a PDSCH or PSSCH, or on a dedicated data channel, e.g. for low latency and / or high reliability, e.g. a URLLC channel. Control signalling may be on a control channel, for example on a common control channel or a PDCCH or PSCCH, and / or comprise one or more DCI messages or SCI messages. In some cases, the subject transmission may com- 1955

[0225] P111608W001 54 / 77 prise, or represent, reference signalling. For example, it may comprise DM-RS and / or pilot signalling and / or discovery signalling and / or sounding signalling and / or phase tracking signalling and / or cell-specific reference signalling and / or user-specific signalling, in particular CSI-RS. A subject transmission may pertain to one scheduling assignment and / or one acknowledgement signalling process (e.g., according to identifier or subidentifier), 1960 and / or one subdivision. In some cases, a subject transmission may cross the borders of subdivisions in time, e.g. due to being scheduled to start in one subdivision and extending into another, or even crossing over more than one subdivision. In this case, it may be considered that the subject transmission is associated to the subdivision it ends in.

[0226] It may be considered that transmitting acknowledgement information, in particular of ac- 1965 knowledgement information, is based on determining whether the subject transmission / s has or have been received correctly, e.g. based on error coding and / or reception quality. Reception quality may for example be based on a determined signal quality. Acknowledgement information may generally be transmitted to a signalling radio node and / or node arrangement and / or to a network and / or network node. 1970

[0227] Acknowledgement information, or bit / s of a subpattern structure of such information (e.g., an acknowledgement information structure, may represent and / or comprise one or more bits, in particular a pattern of bits. Multiple bits pertaining to a data structure or substructure or message like a control message may be considered a subpattern. The structure or arrangement of acknowledgement information may indicate the order, and / or 1975 meaning, and / or mapping, and / or pattern of bits (or subpatterns of bits) of the information. The structure or mapping may in particular indicate one or more data block structures, e.g. code blocks and / or code block groups and / or transport blocks and / or messages, e.g. command messages, the acknowledgement information pertains to, and / or which bits or subpattern of bits are associated to which data block structure. In some 1980 cases, the mapping may pertain to one or more acknowledgement signalling processes, e.g. processes with different identifiers, and / or one or more different data streams. The configuration or structure or codebook may indicate to which process / es and / or data stream / s the information pertains. Generally, the acknowledgement information may comprise one or more subpatterns, each of which may pertain to a data block structure, e.g. a 1985 code block or code block group or transport block. A subpattern may be arranged to indicate acknowledgement or non-acknowledgement, or another retransmission state like non-scheduling or non-reception, of the associated data block structure. It may be considered that a subpattern comprises one bit, or in some cases more than one bit. It should be noted that acknowledgement information may be subjected to significant processing 1990 before being transmitted with acknowledgement signalling. Different configurations may indicate different sizes and / or mapping and / or structures and / or pattern.

[0228] P111608W001 55 / 77 An acknowledgment signalling process (providing acknowledgment information) may be a HARQ process, and / or be identified by a process identifier, e.g. a HARQ process identifier or sub-identifier. Acknowledgement signalling and / or associated acknowledgement 1995 information may be referred to as feedback or acknowledgement feedback. It should be noted that data blocks or structures to which subpatterns may pertain may be intended to carry data (e.g., information and / or systemic and / or coding bits). However, depending on transmission conditions, such data may be received or not received (or not received correctly), which may be indicated correspondingly in the feedback. In some cases, a 2000 subpattern of acknowledgement signalling may comprise padding bits, e.g. if the acknowledgement information for a data block requires fewer bits than indicated as size of the subpattern. Such may for example happen if the size is indicated by a unit size larger than required for the feedback.

[0229] Acknowledgment information may generally indicate at least ACK or NACK, e.g. per- 2005 taining to an acknowledgment signalling process, or an element of a data block structure like a data block, subblock group or subblock, or a message, in particular a control message. Generally, to an acknowledgment signalling process there may be associated one specific subpattern and / or a data block structure, for which acknowledgment information may be provided. Acknowledgement information may comprise a plurality of pieces of 2010 information, represented in a plurality of ARQ and / or HARQ structures.

[0230] An acknowledgment signalling process may determine correct or incorrect reception, and / or corresponding acknowledgement information, of a data block like a transport block, and / or substructures thereof, based on coding bits associated to the data block, and / or based on coding bits associated to one or more data block and / or subblocks 2015 and / or subblock group / s. Acknowledgement information (determined by an acknowledgement signalling process) may pertain to the data block as a whole, and / or to one or more subblocks or subblock groups. A code block may be considered an example of a subblock, whereas a code block group may be considered an example of a subblock group. Accordingly, the associated subpattern may comprise one or more bits indicating 2020 reception status or feedback of the data block, and / or one or more bits indicating reception status or feedback of one or more subblocks or subblock groups. Each subpattern or bit of the subpattern may be associated and / or mapped to a specific data block or subblock or subblock group. In some variants, correct reception for a data block may be indicated if all subblocks or subblock groups are correctly identified. In such a case, the 2025 subpattern may represent acknowledgement information for the data block as a whole, reducing overhead in comparison to provide acknowledgement information for the subblocks or subblock groups. The smallest structure (e.g. subblock / subblock group / data block) the subpattern provides acknowledgement information for and / or is associated to

[0231] P111608W001 56 / 77 may be considered its (highest) resolution. In some variants, a subpattern may provide 2030 acknowledgment information regarding several elements of a data block structure and / or at different resolution, e.g. to allow more specific error detection. For example, even if a subpattern indicates acknowledgment signalling pertaining to a data block as a whole, in some variants higher resolution (e.g., subblock or subblock group resolution) may be provided by the subpattern. A subpattern may generally comprise one or more bits indi- 2035 eating ACK / NACK for a data block, and / or one or more bits for indicating ACK / NACK for a subblock or subblock group, or for more than one subblock or subblock group.

[0232] A subblock and / or subblock group may comprise information bits (representing the data to be transmitted, e.g. user data and / or downlink / sidelink data or uplink data). It may be considered that a data block and / or subblock and / or subblock group also comprises error 2040 one or more error detection bits, which may pertain to, and / or be determined based on, the information bits (for a subblock group, the error detection bit / s may be determined based on the information bits and / or error detection bits and / or error correction bits of the subblock / s of the subblock group). A data block or substructure like subblock or subblock group may comprise error correction bits, which may in particular be determined based 2045 on the information bits and error detection bits of the block or substructure, e.g. utilising an error correction coding scheme, in particular for forward error correction (FEC), e.g. LDPC or polar coding and / or turbo coding. Generally, the error correction coding of a data block structure (and / or associated bits) may cover and / or pertain to information bits and error detection bits of the structure. A subblock group may represent a combination of 2050 one or more code blocks, respectively the corresponding bits. A data block may represent a code block or code block group, or a combination of more than one code block groups.

[0233] A transport block may be split up in code blocks and / or code block groups, for example based on the bit size of the information bits of a higher layer data structure provided for error coding and / or size requirements or preferences for error coding, in particular 2055 error correction coding. Such a higher layer data structure is sometimes also referred to as transport block, which in this context represents information bits without the error coding bits described herein, although higher layer error handling information may be included, e.g. for an internet protocol like TCP. However, such error handling information represents information bits in the context of this disclosure, as the acknowledgement 2060 signalling procedures described treat it accordingly.

[0234] In some variants, a subblock like a code block may comprise error correction bits, which may be determined based on the information bit / s and / or error detection bit / s of the subblock. An error correction coding scheme may be used for determining the error correction bits, e.g. based on LDPC or polar coding or Reed-Mueller coding. In some cases, 2065 a subblock or code block may be considered to be defined as a block or pattern of bits

[0235] P111608W001 57 / 77 comprising information bits, error detection bit / s determined based on the information bits, and error correction bit / s determined based on the information bits and / or error detection bit / s. It may be considered that in a subblock, e.g. code block, the information bits (and possibly the error correction bit / s) are protected and / or covered by the error 2070 correction scheme or corresponding error correction bit / s. A code block group may comprise one or more code blocks. In some variants, no additional error detection bits and / or error correction bits are applied, however, it may be considered to apply either or both. A transport block may comprise one or more code block groups. It may be considered that no additional error detection bits and / or error correction bits are applied to a transport 2075 block, however, it may be considered to apply either or both. In some specific variants, the code block group / s comprise no additional layers of error detection or correction coding, and the transport block may comprise only additional error detection coding bits, but no additional error correction coding. This may particularly be true if the transport block size is larger than the code block size and / or the maximum size for error correction 2080 coding. A subpattern of acknowledgement signalling (in particular indicating ACK or NACK) may pertain to a code block, e.g. indicating whether the code block has been correctly received. It may be considered that a subpattern pertains to a subgroup like a code block group or a data block like a transport block. In such cases, it may indicate ACK, if all subblocks or code blocks of the group or data / transport block are received 2085 correctly (e.g. based on a logical AND operation), and NACK or another state of noncorrect reception if at least one subblock or code block has not been correctly received. It should be noted that a code block may be considered to be correctly received not only if it actually has been correctly received, but also if it can be correctly reconstructed based on soft-combining and / or the error correction coding. 2090

[0236] A subpattern / HARQ structure may pertain to one acknowledgement signalling process and / or one carrier like a component carrier and / or data block structure or data block. It may in particular be considered that one (e.g. specific and / or single) subpattern pertains, e.g. is mapped by the codebook, to one (e.g., specific and / or single) acknowledgement signalling process, e.g. a specific and / or single HARQ process. It may be considered 2095 that in the bit pattern, subpatterns are mapped to acknowledgement signalling processes and / or data blocks or data block structures on a one-to-one basis. In some variants, there may be multiple subpatterns (and / or associated acknowledgment signalling processes) associated to the same component carrier, e.g. if multiple data streams transmitted on the carrier are subject to acknowledgement signalling processes. A subpattern may 2100 comprise one or more bits, the number of which may be considered to represent its size or bit size. Different bit n-tupels (n being 1 or larger) of a subpattern may be associated to different elements of a data block structure (e.g., data block or subblock or subblock

[0237] P111608W001 58 / 77 group), and / or represent different resolutions. There may be considered variants in which only one resolution is represented by a bit pattern, e.g. a data block. A bit n-tupel 2105 may represent acknowledgement information (also referred to a feedback), in particular ACK or NACK, and optionally, (if n^,l), may represent DTX / DRX or other reception states. ACK / NACK may be represented by one bit, or by more than one bit, e.g. to improve disambiguity of bit sequences representing ACK or NACK, and / or to improve transmission reliability. 2110

[0238] The acknowledgement information or feedback information may pertain to a plurality of different transmissions, which may be associated to and / or represented by data block structures, respectively the associated data blocks or data signalling. The data block structures, and / or the corresponding blocks and / or signalling, may be scheduled for simultaneous transmission, e.g. for the same transmission timing structure, in particular 2115 within the same slot or subframe, and / or on the same symbol / s. However, alternatives with scheduling for non-simultaneous transmission may be considered. For example, the acknowledgment information may pertain to data blocks scheduled for different transmission timing structures, e.g. different slots (or mini-slots, or slots and mini-slots) or similar, which may correspondingly be received (or not or wrongly received). Schedul- 2120 ing signalling may generally comprise indicating resources, e.g. time and / or frequency resources, for example for receiving or transmitting the scheduled signalling.

[0239] Signalling may generally be considered to represent an electromagnetic wave structure (e.g., over a time interval and frequency interval), which is intended to convey information to at least one specific or generic (e.g., anyone who might pick up the signalling) 2125 target. A process of signalling may comprise transmitting the signalling. Transmitting signalling, in particular control signalling or communication signalling, e.g. comprising or representing acknowledgement signalling and / or resource requesting information, may comprise encoding and / or modulating. Encoding and / or modulating may comprise error detection coding and / or forward error correction encoding and / or scrambling. Receiving 2130 control signalling may comprise corresponding decoding and / or demodulation. Error detection coding may comprise, and / or be based on, parity or checksum approaches, e.g. CRC (Cyclic Redundancy Check). Forward error correction coding may comprise and / or be based on for example turbo coding and / or Reed-Muller coding, and / or polar coding and / or LDPC coding (Low Density Parity Check). The type of coding used may be based 2135 on the channel (e.g., physical channel) the coded signal is associated to. A code rate may represent the ratio of the number of information bits before encoding to the number of encoded bits after encoding, considering that encoding adds coding bits for error detection coding and forward error correction. Coded bits may refer to information bits (also called systematic bits) plus coding bits. 2140

[0240] P111608W001 59 / 77 Communication signalling may comprise, and / or represent, and / or be implemented as, data signalling, and / or user plane signalling. Communication signalling may be associated to a data channel, e.g. a physical downlink channel or physical uplink channel or physical sidelink channel, in particular a PDSCH (Physical Downlink Shared Channel) or PSSCH (Physical Sidelink Shared Channel). Generally, a data channel may be a shared channel 2145 or a dedicated channel. Data signalling may be signalling associated to and / or on a data channel.

[0241] An indication generally may explicitly and / or implicitly indicate the information it represents and / or indicates. Implicit indication may for example be based on position and / or resource used for transmission. Explicit indication may for example be based 2150 on a parametrisation with one or more parameters, and / or one or more index or indices, and / or one or more bit patterns representing the information. It may in particular be considered that control signalling as described herein, based on the utilised resource sequence, implicitly indicates the control signalling type.

[0242] A resource element may generally describe the smallest individually usable and / or en- 2155 codable and / or decodable and / or modulatable and / or demodulatable time-frequency resource, and / or may describe a time-frequency resource covering a symbol time length in time and a subcarrier in frequency. A signal may be allocatable and / or allocated to a resource element. A subcarrier may be a subband of a carrier, e.g. as defined by a standard. A carrier may define a frequency and / or frequency band for transmission and / or 2160 reception. In some variants, a signal (jointly encoded / modulated) may cover more than one resource elements. A resource element may generally be as defined by a corresponding standard, e.g. NR or LTE. As symbol time length and / or subcarrier spacing (and / or numerology) may be different between different symbols and / or subcarriers, different resource elements may have different extension (length / width) in time and / or frequency 2165 domain, in particular resource elements pertaining to different carriers.

[0243] A resource generally may represent a time-frequency and / or code resource, on which signalling, e.g. according to a specific format, may be communicated, for example transmitted and / or received, and / or be intended for transmission and / or reception.

[0244] A border symbol may generally represent a starting symbol or an ending symbol for 2170 transmitting and / or receiving. A starting symbol may in particular be a starting symbol of uplink or sidelink signalling, for example control signalling or data signalling. Such signalling may be on a data channel or control channel, e.g. a physical channel, in particular a physical uplink shared channel (like PUSCH) or a sidelink data or shared channel, or a physical uplink control channel (like PUCCH) or a sidelink control channel. 2175 If the starting symbol is associated to control signalling (e.g., on a control channel), the

[0245] P111608W001 60 / 77 control signalling may be in response to received signalling (in sidelink or downlink), e.g. representing acknowledgement signalling associated thereto, which may be HARQ or ARQ signalling. An ending symbol may represent an ending symbol (in time) of downlink or sidelink transmission or signalling, which may be intended or scheduled for the radio node 2180 or user equipment. Such downlink signalling may in particular be data signalling, e.g. on a physical downlink channel like a shared channel, e.g. a PDSCH (Physical Downlink Shared Channel). A starting symbol may be determined based on, and / or in relation to, such an ending symbol.

[0246] Configuring a radio node, in particular a terminal or user equipment, may refer to the 2185 radio node being adapted or caused or set and / or instructed to operate according to the configuration. Configuring may be done by another device, e.g., a network node (for example, a radio node of the network like a base station or eNodeB) or network, in which case it may comprise transmitting configuration data to the radio node to be configured.

[0247] Such configuration data may represent the configuration to be configured and / or comprise 2190 one or more instruction pertaining to a configuration, e.g. a configuration for transmitting and / or receiving on allocated resources, in particular frequency resources. A radio node may configure itself, e.g., based on configuration data received from a network or network node. A network node may utilise, and / or be adapted to utilise, its circuitry / ies for configuring. Allocation information may be considered a form of configuration data. 2195 Configuration data may comprise and / or be represented by configuration information, and / or one or more corresponding indications and / or message / s

[0248] Generally, configuring may include determining configuration data representing the configuration and providing, e.g. transmitting, it to one or more other nodes (parallel and / or sequentially), which may transmit it further to the radio node (or another node, which 2200 may be repeated until it reaches the wireless device). Alternatively, or additionally, configuring a radio node, e.g., by a network node or other device, may include receiving configuration data and / or data pertaining to configuration data, e.g., from another node like a network node, which may be a higher-level node of the network, and / or transmitting received configuration data to the radio node. Accordingly, determining a configuration 2205 and transmitting the configuration data to the radio node may be performed by different network nodes or entities, which may be able to communicate via a suitable interface, e.g., an X2 interface in the case of LTE or a corresponding interface for NR. Configuring a terminal may comprise scheduling downlink and / or uplink transmissions for the terminal, e.g. downlink data and / or downlink control signalling and / or DCI and / or uplink control 2210 or data or communication signalling, in particular acknowledgement signalling, and / or configuring resources and / or a resource pool therefor.

[0249] P111608W001 61 / 77 A resource structure may be considered to be neighboured in frequency domain by another resource structure, if they share a common border frequency, e.g. one as an upper frequency border and the other as a lower frequency border. Such a border may for ex- 2215 ample be represented by the upper end of a bandwidth assigned to a subcarrier n, which also represents the lower end of a bandwidth assigned to a subcarrier n+1. A resource structure may be considered to be neighboured in time domain by another resource structure, if they share a common border time, e.g. one as an upper (or right in the figures) border and the other as a lower (or left in the figures) border. Such a border may for 2220 example be represented by the end of the symbol time interval assigned to a symbol n, which also represents the beginning of a symbol time interval assigned to a symbol n+1.

[0250] Generally, a resource structure being neighboured by another resource structure in a domain may also be referred to as abutting and / or bordering the other resource structure in the domain. 2225

[0251] A resource structure may general represent a structure in time and / or frequency domain, in particular representing a time interval and a frequency interval. A resource structure may comprise and / or be comprised of resource elements, and / or the time interval of a resource structure may comprise and / or be comprised of symbol time interval / s, and / or the frequency interval of a resource structure may comprise and / or be comprised of sub- 2230 carrier / s. A resource element may be considered an example for a resource structure, a slot or mini-slot or a Physical Resource Block (PRB) or parts thereof may be considered others. A resource structure may be associated to a specific channel, e.g. a PUSCH or PUCCH, in particular resource structure smaller than a slot or PRB.

[0252] Examples of a resource structure in frequency domain comprise a bandwidth or band, or 2235 a bandwidth part. A bandwidth part may be a part of a bandwidth available for a radio node for communicating, e.g. due to circuitry and / or configuration and / or regulations and / or a standard. A bandwidth part may be configured or configurable to a radio node. In some variants, a bandwidth part may be the part of a bandwidth used for communicating, e.g. transmitting and / or receiving, by a radio node. The bandwidth 2240 part may be smaller than the bandwidth (which may be a device bandwidth defined by the circuitry / conhguration of a device, and / or a system bandwidth, e.g. available for a RAN). It may be considered that a bandwidth part comprises one or more resource blocks or resource block groups, in particular one or more PRBs or PRB groups. A bandwidth part may pertain to, and / or comprise, one or more carriers. 2245

[0253] A carrier may generally represent a frequency range or band and / or pertain to a central frequency and an associated frequency interval. It may be considered that a carrier comprises a plurality of subcarriers. A carrier may have assigned to it a central frequency or

[0254] P111608W001 62 / 77 center frequency interval, e.g. represented by one or more subcarriers (to each subcarrier there may be generally assigned a frequency bandwidth or interval). Different carriers 2250 may be non-overlapping, and / or may be neighbouring in frequency domain.

[0255] It should be noted that the term “radio” in this disclosure may be considered to pertain to wireless communication in general, and may also include wireless communication utilising millimeter waves, in particular above one of the thresholds 10 GHz or 20 GHz or 50 GHz or 52 GHz or 52.6 GHz or 60 GHz or 72 GHz or 100 GHz or 114 GHz. Such communication 2255 may utilise one or more carriers, e.g. in FDD and / or carrier aggregation. Upper frequency boundaries may correspond to 300 GHz or 200 GHz or 120 GHz or any of the thresholds larger than the one representing the lower frequency boundary.

[0256] A radio node, in particular a network node or a terminal, may generally be any device adapted for transmitting and / or receiving radio and / or wireless signals and / or data, in 2260 particular communication data, in particular on at least one carrier. The at least one carrier may comprise a carrier accessed based on an LBT procedure (which may be called LBT carrier), e.g., an unlicensed carrier. It may be considered that the carrier is part of a carrier aggregate.

[0257] Receiving or transmitting on a cell or carrier may refer to receiving or transmitting utiliz- 2265 ing a frequency (band) or spectrum associated to the cell or carrier. A cell may generally comprise and / or be defined by or for one or more carriers, in particular at least one carrier for UL communication / transmission (called UL carrier) and at least one carrier for DL communication / transmission (called DL carrier). It may be considered that a cell comprises different numbers of UL carriers and DL carriers. Alternatively, or addition- 2270 ally, a cell may comprise at least one carrier for UL communication / transmission and DL communication / transmission, e.g., in TDD-based approaches.

[0258] A channel may generally be a logical, transport or physical channel. A channel may comprise and / or be arranged on one or more carriers, in particular a plurality of subcarriers.

[0259] A channel carrying and / or for carrying control signalling / control information may be con- 2275 sidered a control channel, in particular if it is a physical layer channel and / or if it carries control plane information. Analogously, a channel carrying and / or for carrying data signalling / user information may be considered a data channel, in particular if it is a physical layer channel and / or if it carries user plane information. A channel may be defined for a specific communication direction, or for two complementary communication directions 2280 (e.g., UL and DL, or sidelink in two directions), in which case it may be considered to have two component channels, one for each direction. Examples of channels comprise a channel for low latency and / or high reliability transmission, in particular a channel for Ultra- Reliable Low Latency Communication (URLLC), which may be for control and / or

[0260] P111608W001 63 / 77 data. 2285

[0261] In general, a symbol may represent and / or be associated to a symbol time length, which may be dependent on the carrier and / or subcarrier spacing and / or numerology of the associated carrier. Accordingly, a symbol may be considered to indicate a time interval having a symbol time length in relation to frequency domain. A symbol time length may be dependent on a carrier frequency and / or bandwidth and / or numerology and / or 2290 subcarrier spacing of, or associated to, a symbol. Accordingly, different symbols may have different symbol time lengths. In particular, numerologies with different subcarrier spacings may have different symbol time length. Generally, a symbol time length may be based on, and / or include, a guard time interval or cyclic extension, e.g. prefix or postfix.

[0262] A sidelink may generally represent a communication channel (or channel structure) be- 2295 tween two UEs and / or terminals, in which data is transmitted between the participants (UEs and / or terminals) via the communication channel, e.g. directly and / or without being relayed via a network node. A sidelink may be established only and / or directly via air interface / s of the participant, which may be directly linked via the sidelink communication channel. In some variants, sidelink communication may be performed without 2300 interaction by a network node, e.g. on fixedly defined resources and / or on resources negotiated between the participants. Alternatively, or additionally, it may be considered that a network node provides some control functionality, e.g. by configuring resources, in particular one or more resource pool / s, for sidelink communication, and / or monitoring a sidelink, e.g. for charging purposes. 2305

[0263] Sidelink communication may also be referred to as device-to-device (D2D) communication, and / or in some cases as ProSe (Proximity Services) communication, e.g. in the context of LTE. A sidelink may be implemented in the context of V2x communication (Vehicular communication), e.g. V2V (Vehicle-to- Vehicle), V2I (Vehicle-to-Infrastructure) and / or V2P (Vehicle-to- Person). Any device adapted for sidelink communication may be consid- 2310 ered a user equipment or terminal.

[0264] A sidelink communication channel (or structure) may comprise one or more (e.g., physical or logical) channels, e.g. a PSCCH (Physical Sidelink Control CHannel, which may for example carry control information like an acknowledgement position indication, and / or a PSSCH (Physical Sidelink Shared CHannel, which for example may carry data and / or 2315 acknowledgement signalling). It may be considered that a sidelink communication channel (or structure) pertains to and / or used one or more carrier / s and / or frequency range / s associated to, and / or being used by, cellular communication, e.g. according to a specific license and / or standard. Participants may share a (physical) channel and / or resources, in particular in frequency domain and / or related to a frequency resource like a carrier) 2320

[0265] P111608W001 64 / 77 of a sidelink, such that two or more participants transmit thereon, e.g. simultaneously, and / or time-shifted, and / or there may be associated specific channels and / or resources to specific participants, so that for example only one participant transmits on a specific channel or on a specific resource or specific resources, e.g., in frequency domain and / or related to one or more carriers or subcarriers. 2325

[0266] A sidelink may comply with, and / or be implemented according to, a specific standard, e.g. an LTE-based standard and / or NR. A sidelink may utilise TDD (Time Division Duplex) and / or FDD (Frequency Division Duplex) technology, e.g. as configured by a network node, and / or preconfigured and / or negotiated between the participants. A user equipment may be considered to be adapted for sidelink communication if it, and / or its 2330 radio circuitry and / or processing circuitry, is adapted for utilising a sidelink, e.g. on one or more frequency ranges and / or carriers and / or in one or more formats, in particular according to a specific standard. It may be generally considered that a Radio Access Network is defined by two participants of a sidelink communication. Alternatively, or additionally, a Radio Access Network may be represented, and / or defined with, and / or 2335 be related to a network node and / or communication with such a node.

[0267] Communication or communicating may generally comprise transmitting and / or receiving signalling. Communication on a sidelink (or sidelink signalling) may comprise utilising the sidelink for communication (respectively, for signalling). Sidelink transmission and / or transmitting on a sidelink may be considered to comprise transmission utilising the 2340 sidelink, e.g. associated resources and / or transmission formats and / or circuitry and / or the air interface. Sidelink reception and / or receiving on a sidelink may be considered to comprise reception utilising the sidelink, e.g. associated resources and / or transmission formats and / or circuitry and / or the air interface. Sidelink control information (e.g., SCI) may generally be considered to comprise control information transmitted utilising a 2345 sidelink.

[0268] Generally, carrier aggregation (CA) may refer to the concept of a radio connection and / or communication link between a wireless and / or cellular communication network and / or network node and a terminal or on a sidelink comprising a plurality of carriers for at least one direction of transmission (e.g. DL and / or UL), as well as to the aggregate of carriers. 2350 A corresponding communication link may be referred to as carrier aggregated communication link or CA communication link; carriers in a carrier aggregate may be referred to as component carriers (CC). In such a link, data may be transmitted over more than one of the carriers and / or all the carriers of the carrier aggregation (the aggregate of carriers). A carrier aggregation may comprise one (or more) dedicated control carriers and / or 2355 primary carriers (which may e.g. be referred to as primary component carrier or PCC),

[0269] P111608W001 65 / 77 over which control information may be transmitted, wherein the control information may refer to the primary carrier and other carriers, which may be referred to as secondary carriers (or secondary component carrier, SCC). However, in some approaches, control information may be sent over more than one carrier of an aggregate, e.g. one or more 2360 PCCs and one PCC and one or more SCCs.

[0270] A transmission may generally pertain to a specific channel and / or specific resources, in particular with a starting symbol and ending symbol in time, covering the interval therebetween. A scheduled transmission may be a transmission scheduled and / or expected and / or for which resources are scheduled or provided or reserved. However, not every 2365 scheduled transmission has to be realized. For example, a scheduled downlink transmission may not be received, or a scheduled uplink transmission may not be transmitted due to power limitations, or other influences (e.g., a channel on an unlicensed carrier being occupied). A transmission may be scheduled for a transmission timing substructure (e.g., a mini-slot, and / or covering only a part of a transmission timing structure) within a 2370 transmission timing structure like a slot. A border symbol may be indicative of a symbol in the transmission timing structure at which the transmission starts or ends.

[0271] Predefined in the context of this disclosure may refer to the related information being defined for example in a standard, and / or being available without specific configuration from a network or network node, e.g. stored in memory, for example independent of being 2375 configured. Configured or configurable may be considered to pertain to the corresponding information being set / conhgured, e.g. by the network or a network node.

[0272] A configuration or schedule, like a mini-slot configuration and / or structure configuration, may schedule transmissions, e.g. for the time / transmissions it is valid, and / or transmissions may be scheduled by separate signalling or separate configuration, e.g. separate RRC 2380 signalling and / or downlink control information signalling. The transmission / s scheduled may represent signalling to be transmitted by the device for which it is scheduled, or signalling to be received by the device for which it is scheduled, depending on which side of a communication the device is. It should be noted that downlink control information or specifically DCI signalling may be considered physical layer signalling, in contrast to 2385 higher layer signalling like MAC (Medium Access Control) signalling or RRC layer signalling. The higher the layer of signalling is, the less frequent / the more time / resource consuming it may be considered, at least partially due to the information contained in such signalling having to be passed on through several layers, each layer requiring processing and handling. 2390

[0273] A scheduled transmission, and / or transmission timing structure like a mini-slot or slot, may pertain to a specific channel, in particular a physical uplink shared channel, a physical

[0274] P111608W001 66 / 77 uplink control channel, or a physical downlink shared channel, e.g. PUSCH, PUCCH or PDSCH, and / or may pertain to a specific cell and / or carrier aggregation. A corresponding configuration, e.g. scheduling configuration or symbol configuration may pertain to 2395 such channel, cell and / or carrier aggregation. It may be considered that the scheduled transmission represents transmission on a physical channel, in particular a shared physical channel, for example a physical uplink shared channel or physical downlink shared channel. For such channels, semi-persistent configuring may be particularly suitable.

[0275] Generally, a configuration may be a configuration indicating timing, and / or be represented 2400 or configured with corresponding configuration data. A configuration may be embedded in, and / or comprised in, a message or configuration or corresponding data, which may indicate and / or schedule resources, in particular semi-persistently and / or semi-statically.

[0276] A control region of a transmission timing structure may be an interval in time and / or frequency domain for intended or scheduled or reserved for control signalling, in particular 2405 downlink control signalling, and / or for a specific control channel, e.g. a physical downlink control channel like PDCCH. The interval may comprise, and / or consist of, a number of symbols in time, which may be configured or configurable, e.g. by (UE-specific) dedicated signalling (which may be single-cast, for example addressed to or intended for a specific

[0277] UE), e.g. on a PDCCH, or RRC signalling, or on a multicast or broadcast channel. 2410 In general, the transmission timing structure may comprise a control region covering a configurable number of symbols. It may be considered that in general the border symbol is configured to be after the control region in time. A control region may be associated, e.g. via configuration and / or determination, to one or more specific UEs and / or formats of PDCCH and / or DCI and / or identifiers, e.g. UE identifiers and / or RNTIs or carrier / cell 2415 identifiers, and / or be represented and / or associated to a CORESET and / or a search space.

[0278] The duration of a symbol (symbol time length or interval) of the transmission timing structure may generally be dependent on a numerology and / or carrier, wherein the numerology and / or carrier may be configurable. The numerology may be the numerology 2420 to be used for the scheduled transmission.

[0279] A transmission timing structure may comprise a plurality of symbols, and / or define an interval comprising several symbols (respectively their associated time intervals). In the context of this disclosure, it should be noted that a reference to a symbol for ease of reference may be interpreted to refer to the time domain projection or time interval or time 2425 component or duration or length in time of the symbol, unless it is clear from the context that the frequency domain component also has to be considered. Examples of transmission timing structures include slot, subframe, mini-slot (which also may be considered a

[0280] P1116D8WOD1 67 / 77 substructure of a slot), slot aggregation (which may comprise a plurality of slots and may be considered a superstructure of a slot), respectively their time domain component. A 2430 transmission timing structure may generally comprise a plurality of symbols defining the time domain extension (e.g., interval or length or duration) of the transmission timing structure, and arranged neighboring to each other in a numbered sequence. A timing structure (which may also be considered or implemented as synchronisation structure) may be defined by a succession of such transmission timing structures, which may for 2435 example define a timing grid with symbols representing the smallest grid structures. A transmission timing structure, and / or a border symbol or a scheduled transmission may be determined or scheduled in relation to such a timing grid. A transmission timing structure of reception may be the transmission timing structure in which the scheduling control signalling is received, e.g. in relation to the timing grid. A transmission timing 2440 structure may in particular be a slot or subframe or in some cases, a mini-slot.

[0281] Feedback signalling may be considered a form or control signalling, e.g. uplink or sidelink control signalling, like UCI (Uplink Control Information) signalling or SCI (Sidelink Control Information) signalling. Feedback signalling may in particular comprise and / or represent acknowledgement signalling and / or acknowledgement information and / or measure- 2445 ment reporting. signalling utilising, and / or on and / or associated to, resources or a resource structure may be signalling covering the resources or structure, signalling on the associated frequency / ies and / or in the associated time interval / s. It may be considered that a signalling resource structure comprises and / or encompasses one or more substructures, which may be as- 2450 sociated to one or more different channels and / or types of signalling and / or comprise one or more holes (resource element / s not scheduled for transmissions or reception of transmissions). A resource substructure, e.g. a feedback resource structure, may generally be continuous in time and / or frequency, within the associated intervals. It may be considered that a substructure, in particular a feedback resource structure, represents a 2455 rectangle filled with one or more resource elements in time / frequency space. However, in some cases, a resource structure or substructure, in particular a frequency resource range, may represent a non-continuous pattern of resources in one or more domains, e.g. time and / or frequency. The resource elements of a substructure may be scheduled for associated signalling. 2460

[0282] Example types of signalling comprise signalling of a specific communication direction, in particular, uplink signalling, downlink signalling, sidelink signalling, as well as reference signalling (e.g., SRS or CRS or CSI-RS), communication signalling, control signalling, and / or signalling associated to a specific channel like PUSCH, PDSCH, PUCCH, PDCCH,

[0283] P111608W001 68 / 77 PSCCH, PSSCH, etc.). 2465

[0284] In the context of this disclosure, there may be distinguished between dynamically scheduled or aperiodic transmission and / or configuration, and semi-static or semi-persistent or periodic transmission and / or configuration. The term “dynamic” or similar terms may generally pertain to conhguration / transmission valid and / or scheduled and / or configured for (relatively) short timescales and / or a (e.g., predefined and / or configured and / or lim- 2470 ited and / or definite) number of occurrences and / or transmission timing structures, e.g. one or more transmission timing structures like slots or slot aggregations, and / or for one or more (e.g., specific number) of transmission / occurrences. Dynamic configuration may be based on low-level signalling, e.g. control signalling on the physical layer and / or MAC layer, in particular in the form of DCI or SCI. Periodic / semi-static may pertain to longer 2475 timescales, e.g. several slots and / or more than one frame, and / or a non-dehned number of occurrences, e.g., until a dynamic configuration contradicts, or until a new periodic configuration arrives. A periodic or semi-static configuration may be based on, and / or be configured with, higher-layer signalling, in particular RCL layer signalling and / or RRC signalling and / or MAC signalling. 2480

[0285] In this disclosure, for purposes of explanation and not limitation, specific details are set forth (such as particular network functions, processes and signalling steps) in order to provide a thorough understanding of the technique presented herein. It will be apparent to one skilled in the art that the present concepts and aspects may be practised in other variants and variants that depart from these specific details. 2485

[0286] For example, the concepts and variants are partially described in the context of Long Term Evolution (LTE) or LTE- Advanced (LTE-A) or New Radio mobile or wireless communications technologies; however, this does not rule out the use of the present concepts and aspects in connection with additional or alternative mobile communication technologies such as the Global System for Mobile Communications (GSM) or IEEE standards as 2490 IEEE 802. Had or IEEE 802.11 ay. While described variants may pertain to certain Technical Specifications (TSs) of the Third Generation Partnership Project (3GPP), it will be appreciated that the present approaches, concepts and aspects could also be realized in connection with different Performance Management (PM) specifications.

[0287] Moreover, those skilled in the art will appreciate that the services, functions and steps 2495 explained herein may be implemented using software functioning in conjunction with a programmed microprocessor, or using an Application Specific Integrated Circuit (ASIC), a Digital Signal Processor (DSP), a Field Programmable Gate Array (FPGA) or general purpose computer. It will also be appreciated that while the variants described herein are elucidated in the context of methods and devices, the concepts and aspects presented 2500

[0288] P111608W001 69 / 77 herein may also be embodied in a program product as well as in a system comprising control circuitry, e.g. a computer processor and a memory coupled to the processor, wherein the memory is encoded with one or more programs or program products that execute the services, functions and steps disclosed herein.

[0289] It is believed that the advantages of the aspects and variants presented herein will be fully 2505 understood from the foregoing description, and it will be apparent that various changes may be made in the form, constructions and arrangement of the exemplary aspects thereof without departing from the scope of the concepts and aspects described herein or without sacrificing all of its advantageous effects. The aspects presented herein can be varied in many ways. 2510

[0290] P111608W001 70 / 77 Some useful abbreviations comprise

[0291] Abbreviation Explanation

[0292] ABF Analog beamformer, fanout to antenna+beamforming

[0293] ACK / NACK Acknowledgment / Negative Acknowledgement

[0294] Ant Antenna

[0295] AoA Angle of Arrival

[0296] ARQ Automatic Repeat reQuest

[0297] BB BaseBand

[0298] Beamindex IF beamindex interface

[0299] BER Bit Error Rate

[0300] BI Beam Index

[0301] BLER Block Error Rate

[0302] BPSK Binary Phase Shift Keying

[0303] BWP BandWidth Part

[0304] CAZAC Constant Amplitude Zero Cross Correlation

[0305] CB Code Block

[0306] CBB Code Block Bundle

[0307] CBG Code Block Group

[0308] CDM Code Division Multiplex

[0309] CM Cubic Metric

[0310] CNN Convolution Neural Network

[0311] Comm RXBB communication receiver baseband

[0312] CORESET Control Resource Set

[0313] CP Cyclic Prefix

[0314] CP rem CP removal

[0315] CQI Channel Quality Information

[0316] CRC Cyclic Redundancy Check

[0317] CRS Common reference signal

[0318] CSI Channel State Information

[0319] CSI-RS Channel state information reference signal

[0320] DAI Downlink Assignment Indicator

[0321] DCI Downlink Control Information

[0322] DFE Digital Frontend

[0323] DFT Discrete Fourier Transform

[0324] DFTS-FDM DFT-spread-FDM

[0325] DM(-)RS Demodulation reference signal(ing)

[0326] DOP Dilution of Precision

[0327] P111608W001 71 / 77 eMBB enhanced Mobile BroadBand FDD Frequency Division Duplex FDE Frequency Domain Equalisation FDF Frequency Domain Filtering FDM Frequency Division Multiplex FFT Fast Fourier Transform GPIO General Purpose Input Output HARQ Hybrid Automatic Repeat Request IAB Integrated Access and Backhaul IFFT Inverse Fast Fourier Transform Im Imaginary part, e.g. for pi / 2*BPSK modulation IR Impulse Response ISAC Integrated Sensing and Communication ISI Inter Symbol Interference JCAS Joint Communication and Sensing MBB Mobile Broadband MCS Modulation and Coding Scheme MIMO Multiple-input-multiple-output MRC Maximum-ratio combining MRT Maximum-ratio transmission MU-MIMO Multiuser multiple- input-multiple-output OFDM / A Orthogonal Frequency Division Multiplex / Multiple Access PAPR Peak to Average Power Ratio PDCCH Physical Downlink Control Channel PDSCH Physical Downlink Shared Channel PRACH Physical Random Access CHannel PRB Physical Resource Block PRS Positioning Reference Signal(ing) PUCCH Physical Uplink Control Channel PUSCH Physical Uplink Shared Channel (P)SCCH (Physical) Sidelink Control Channel PSS Primary Synchronisation Signal(ing) PT-RS Phase Tracking Reference signalling (P)SSCH (Physical) Sidelink Shared Channel QAM Quadrature Amplitude Modulation occ Orthogonal Cover Code QPSK Quadrature Phase Shift Keying PSD Power Spectral Density

[0328] P111608W001 72 / 77 RAN Radio Access Network

[0329] RAT Radio Access Technology

[0330] RB Resource Block

[0331] RCS Radar Cross Section

[0332] RE Resource Element

[0333] Re Real part (e.g., for pi / 2*BPSK) modulation

[0334] RF Radio Frequency

[0335] RNTI Radio Network Temporary Identifier

[0336] RRC Radio Resource Control

[0337] RX Receiver, Reception, Reception-related / side

[0338] SA Scheduling Assignment

[0339] SC-FDE Single Carrier Frequency Domain Equalisation

[0340] SC-FDM / A Single Carrier Frequency Division Multiplex / Multiple Access

[0341] SCI Sidelink Control Information

[0342] SINR Signal-to-interference-plus-noise ratio

[0343] SIR Signal-to-interference ratio

[0344] SNR Sign al-to- noise-ratio

[0345] SPI Serial to Parallel Interface

[0346] SR Scheduling Request

[0347] SRS Sounding Reference Signal(ing) sss Secondary Synchronisation Signal(ing)

[0348] SVD Singular- value decomposition

[0349] TB Transport Block

[0350] TDD Time Division Duplex

[0351] TDM Time Division Multiplex

[0352] ToF Time of Flight

[0353] T-RS Tracking Reference signalling or Timing Reference signalling

[0354] TX Transmitter, Transmission, Transmission-related / side

[0355] UCI Uplink Control Information

[0356] UDC Up-Down Converter, mixing from BBj-^RF

[0357] UE User Equipment

[0358] URLLC Ultra Low Latency High Reliability Communication

[0359] VL-MIMO Very- large multiple-input-multiple-output

[0360] WD Wireless Device

[0361] Wfg Waveform Generator

[0362] ZC Zadoff-Chu

[0363] ZF Zero Forcing

[0364] ZP Zero-Power, e.g. muted CSLRS symbol

[0365] P111608W001 73 / 77 Abbreviations may be considered to follow 3GPP usage if applicable.

[0366] P111608W001 74 / 77

Claims

CLAIMS1. Method of operating a radio node in a wireless communication network, the radio node 2515 being adapted for wireless communication, and being adapted for multi-static sensing and / or radar operation, the method comprising selecting a second group of radio nodes for transmission of sensing signalling from a first group of radio nodes based on an error evaluation of radio nodes of the first group of radio nodes, the first group comprising the second group. 25202. Radio node for a wireless communication network, the radio node being adapted for wireless communication, and being adapted for multi-static sensing and / or radar operation, the radio node being adapted for selecting a second group of radio nodes for transmission of sensing signalling from a first group of radio nodes based on an error evaluation of radio nodes of the first group of radio nodes, the first group comprising the 2525 second group.

3. Method or device according to one of the preceding claims, wherein the error evaluation is specific to a target of multi-static sensing, and / or to a sensing area of multi-static sensing.

4. Method or device according to one of the preceding claims, wherein the error evalua- 2530 tion is based on one or more Dilution of Precision, DOP, parameters, and / or comprises optimising DOP.

5. Method or device according to one of the preceding claims, wherein the error evaluation is based on, and / or comprises, error evaluation for radio nodes of the first group of radio nodes. 25356. Method or device according to one of the preceding claims, wherein the first group of radio nodes is variable over time.

7. Method or device according to one of the preceding claims, wherein the second group of radio nodes is variable over time.

8. Method or device according to one of the preceding claims, wherein the first group of 2540 radio nodes is a first group of user equipments, UEs.

9. Method or device according to one of the preceding claims, wherein error evaluation is based on first sensing signalling transmitted by radio nodes of the first group of radio nodes.

10. Method or device according to one of the preceding claims, wherein selecting is based 2545P111608W001 75 / 77on one or more additional criteria or factors.

11. Program product comprising instructions causing processing circuitry to control and / or perform a method according to one of claims 1 or 3 to 10.

12. Carrier medium arrangement carrying and / or storing a program product according to claim 11. 2550P111608W001 76 / 77

Images