Devices and methods for integrated sensing and communication in a mobile network

Abstract

A control entity (130) is disclosed for configuring one or more transmitter devices (110) and / or one or more receiver devices (120) for integrated sensing and communication, ISAC, in a wireless network (100). The control entity (130) is configured to obtain a task indication indicative of a sensing task and / or a communication task in the wireless network (100) and to generate, based on the task indication, one or more ISAC configuration parameters for configuring a constellation shaping scheme of a modulation and coding scheme, MCS, implemented by the one or more ISAC transmitter devices (110) and / or the one or more ISAC receiver devices (120). Moreover, the control entity (130) is configured to provide the one or more ISAC configuration parameters to the one or more ISAC transmitter devices (110) and / or the one or more ISAC receiver devices (120).

Description

[0001] DEVICES AND METHODS FOR INTEGRATED SENSING AND COMMUNICATION IN A MOBILE NETWORK

[0002] TECHNICAL FIELD

[0003] The present disclosure relates to wireless communications. More specifically, the present disclosure relates to devices and methods for integrated sensing and communication, ISAC, in a mobile network, in particular a 3GPP network.

[0004] BACKGROUND

[0005] Existing wireless communication networks have been designed for reliable data transmission by using, for instance, optimized waveforms, modulation and coding, MIMO processing, or power and pilot signal allocation schemes. However, radio signals may also be used for sensing tasks, i.e. determining certain physical parameters related to the environment, such as localization of a transmitting or receiving device, detecting the presence of a passive object, classifying a passive object based on characteristic features of the reflected signal, or estimating the range and velocity based on a delay and a Doppler shift. Each of these sensing tasks usually requires a different structure of the transmit signal for achieving the best performance.

[0006] Future wireless communication systems are envisioned to provide also sensing functionalities in order to provide new services, which is known as integrated sensing and communication (ISAC) or joint sensing and communication (JSC). Different levels of integration are possible, e.g. (a) combination of separate dedicated sensing and communication hardware in one device, (b) using the same hardware for sensing and communication on different time-frequency resources, and (c) using the same signals for sensing and communication.

[0007] The last option provides the best performance, as the available resources are used most efficiently. However, it is in general not possible to achieve the optimal sensing and communication performance at the same time, primarily because of the following two fundamental trade-offs. While communication signals need to be random in order to convey information that is not already known at the receiver, sensing signals should preferably be deterministic or be known at the receiver (e.g. after decoding), in order to provide good correlation properties like a narrow mainlobe or low sidelobes.

[0008] SUMMARY

[0009] It is an objective of the present disclosure to provide improved devices and methods for integrated sensing and communication (ISAC) in a mobile network, in particular a 3GPP network, for providing an optimized trade-off between sensing and communication.

[0010] The foregoing and other objectives are achieved by the subject matter of the independent claims. Further implementation forms are apparent from the dependent claims, the description and the figures. In the following some or more of the following abbreviations and acronyms will be used:

[0011] AIR Achievable Information Rate

[0012] ATSC Advanced Television Systems Committee

[0013] AWGN Additive White Gaussian Noise

[0014] Band-ESS Band-trellis ESS

[0015] BS Base Station

[0016] CFAR Constant False Alarm Rate CK-ESS Complex valued K-ESS

[0017] DCI Downlink Control Information

[0018] DVB Digital Video Broadcasting

[0019] ESS Enumerative Sphere Shaping

[0020] GS Geometric Shaping

[0021] ISAC Integrated Sensing and Communication

[0022] K-ESS Kurtosis-limited ESS

[0023] MCS Modulation and Coding Scheme

[0024] OFDM Orthogonal Frequency Division Multiplexing

[0025] PCS Probabilistic Constellation Shaping

[0026] PSK Phase Shift Keying

[0027] QAM Quadrature Amplitude Modulation

[0028] QPSK Quadrature PSK

[0029] RAN Radio Access Network

[0030] RRC Radio Resource Control

[0031] SF Sensing Function

[0032] SU Sensing Unit

[0033] UE User Equipment

[0034] SO-CFAR Smallest of-CFAR

[0035] According to a first aspect a control entity is provided for configuring, i.e. controlling, one or more transmitter devices and / or one or more receiver devices for integrated sensing and communication, ISAC, in a wireless network. The one or more transmitter devices and the one or more receiver devices are herein also referred to as one or more ISAC transmitter devices and one or more ISAC receiver devices. The control entity according to the first aspect is configured to obtain a task indication indicative of a sensing task and / or a communication task in the wireless network. Moreover, the control entity according to the first aspect is configured to generate, based on the task indication, one or more ISAC configuration parameters for configuring a constellation shaping scheme of a modulation and coding scheme, MCS, implemented by the one or more ISAC transmitter devices and / or the one or more ISAC receiver devices. The control entity according to the first aspect is further configured to provide the one or more ISAC configuration parameters to the one or more ISAC transmitter devices and / or the one or more ISAC receiver devices for configuring the one or more ISAC transmitter devices and / or the one or more ISAC receiver devices with the ISAC configuration parameters. Thus, the control entity according to the first aspect may adapt the constellation shaping scheme used by the one or more ISAC transmitter devices and / or the one or more ISAC receiver devices depending on the sensing task and / or communication task indicated by the task indication.

[0036] In a further possible implementation form, the constellation shaping scheme may be a probabilistic constellation shaping scheme, a geometric constellation shaping scheme or a combination of a probabilistic and geometric constellation shaping scheme. As will be appreciated, while a probabilistic constellation shaping scheme may adjust the probability distribution, i.e. the probability of the constellation points within the complex I / Q plane (for instance starting from a uniform distribution), geometric constellation shaping may adjust the position of one or more constellation points within the complex I / Q plane.

[0037] In a further possible implementation form, the control entity is configured to determine one or more desired sensing performance measures based on the task indication.

[0038] In a further possible implementation form, the one or more desired sensing performance measures comprise a desired sensing detection accuracy and / or an indication of a desired maximum sensing false alarm probability. In a further possible implementation form, the control entity is configured to generate, based on the task indication, the one or more ISAC configuration parameters for configuring the constellation shaping scheme of the MCS implemented by the one or more ISAC transmitter devices and / or the one or more ISAC receiver devices by determining one or more moments of a symbol distribution of an ISAC signal transmitted based on the constellation shaping scheme that achieves the one or more desired sensing performance measures and determining the one or more ISAC configuration parameters based on the one or more moments of the symbol distribution.

[0039] In a further possible implementation form, the one or more moments of the symbol distribution comprise a kurtosis and / or a variance of the symbol distribution.

[0040] In a further possible implementation form, the wireless network comprises, i.e. implements a sensing network function, wherein the sensing network function comprises, i.e. implements the control entity.

[0041] According to a second aspect a method of operating a control entity for configuring one or more transmitter devices and / or one or more receiver devices for integrated sensing and communication, ISAC, in a wireless network. The method according to the second aspect comprises the following steps: obtaining a task indication indicative of a sensing task and / or a communication task in the wireless network; generating, based on the task indication, one or more ISAC configuration parameters for configuring a constellation shaping scheme of a modulation and coding scheme implemented by the one or more transmitter devices and / or the one or more receiver devices; and providing the one or more ISAC configuration parameters to the one or more transmitter devices and / or the one or more receiver devices.

[0042] The method according to the second aspect can be performed by the control entity according to the first aspect. Thus, further features of the method according to the second aspect result directly from the functionality of the control entity according to the first aspect as well as its different implementation forms described above and below.

[0043] According to a third aspect a transmitter device is provided for integrated sensing and communication, ISAC, (also referred to as ISAC transmitter device) in a wireless network, wherein the ISAC transmitter device comprises a communication interface adapted to receive one or more ISAC configuration parameters from a control entity, wherein the one or more ISAC configuration parameters are based on a task indication indicative of a sensing task and / or a communication task in the wireless network. Moreover, the ISAC transmitter device according to the third aspect comprises processing circuitry adapted to configure a constellation shaping scheme of a modulation and coding scheme, MCS, implemented by the ISAC transmitter device based on the one or more ISAC configuration parameters. The communication interface of the ISAC transmitter device according to the third aspect is further configured to transmit one or more ISAC signals to one or more ISAC receiver devices of the wireless network using the configuration of the constellation shaping scheme of the MCS defined by the one or more configuration parameters. Thus, the ISAC transmitter device according to the third aspect may use a constellation shaping scheme adapted for the sensing task and / or communication task indicated by the task indication.

[0044] In a further possible implementation form, the constellation shaping scheme may be a probabilistic constellation shaping scheme, a geometric constellation shaping scheme or a combination of a probabilistic and geometric constellation shaping scheme.

[0045] In a further possible implementation form, the ISAC transmitter device comprises the control entity, i.e. the control entity is collocated with the ISAC transmitter device. In a further possible implementation form, the ISAC transmitter device according to the third aspect is configured to provide the one or more ISAC configuration parameters to one or more of the ISAC receiver devices.

[0046] In a further possible implementation form, the ISAC transmitter device according to the third aspect is a base station or a user equipment, UE, and the one or more ISAC receiver devices are one or more base stations or one or more UEs.

[0047] In a further possible implementation form, the constellation shaping scheme comprises a probabilistic amplitude shaping scheme.

[0048] In a further possible implementation form, the probabilistic amplitude shaping scheme is based on an enumerative sphere shaping scheme.

[0049] In a further possible implementation form, the probabilistic amplitude shaping scheme is based on a Band-limited enumerative sphere shaping scheme.

[0050] In a further possible implementation form, the probabilistic amplitude shaping scheme is based on a Kurtosis-limited enumerative sphere shaping scheme.

[0051] In a further possible implementation form, the probabilistic amplitude shaping scheme is generated based on a trellis enumerating the sequences in the following set: wherein C is the alphabet of all symbols in the first quadrant, which is defined by the MCS, E denotes one or the one or more ISAC configuration parameters associated with a variance, K denotes one of the one or more ISAC configuration parameters associated with the kurtosis, and N denotes a sequence length of the sequence of symbols.

[0052] In a further possible implementation form, the ISAC transmitter device is configured to shape the real and the imaginary part of each complex amplitude jointly.

[0053] In a further possible implementation form, the constellation shaping scheme comprises a geometric constellation shaping scheme based on a machine learning, ML, optimization, one or more evolutionary algorithms, and / or one or more global optimization techniques.

[0054] According to a fourth aspect a method is provided for operating a transmitter device for integrated sensing and communication, ISAC, in a wireless network. The method according to the fourth aspect comprises the following steps: receiving one or more ISAC configuration parameters from a control entity, wherein the one or more ISAC configuration parameters are based on a task indication indicative of a sensing task and / or a communication task in the wireless network; configuring a constellation shaping scheme of a modulation and coding scheme, MCS, implemented by the transmitter device based on the one or more ISAC configuration parameters; and transmitting one or more ISAC signals to one or more receiver devices of the wireless network using the configuration of the constellation shaping scheme of the MCS defined by the one or more configuration parameters. The method according to the fourth aspect can be performed by the transmitter device according to the third aspect. Thus, further features of the method according to the fourth aspect result directly from the functionality of the transmitter device according to the third aspect as well as its different implementation forms described above and below.

[0055] According to a fifth aspect, a computer program product is provided, comprising a computer-readable storage medium for storing program code which causes a computer or a processor to perform the method according to the second aspect or the method according to the fourth aspect, when the program code is executed by the computer or the processor.

[0056] Details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description, drawings, and claims.

[0057] BRIEF DESCRIPTION OF THE DRAWINGS

[0058] In the following, embodiments of the present disclosure are described in more detail with reference to the attached figures and drawings, in which:

[0059] Fig. la shows a schematic diagram illustrating a wireless network including a control entity according to an embodiment for controlling an ISAC transmitter device according to an embodiment and an ISAC receiver device;

[0060] Fig. lb shows a schematic diagram illustrating a sensing task for sensing a target in a wireless network including an ISAC transmitter device according to an embodiment and an ISAC receiver device;

[0061] Figs. 2a and 2b show schematic diagrams illustrating variants of the embodiment of figure la;

[0062] Figs. 3a and 3b show diagrams illustrating two exemplary 64-QAM symbol distributions without and with PCS;

[0063] Fig. 3c shows a diagram illustrating the autocorrelation of a transmit signal for various symbol distributions;

[0064] Figs. 4a and 4b show diagrams illustrating two exemplary 16 point symbol distributions without and with GS;

[0065] Figs. 5a, 5b and 5c show diagrams illustrating a bounded-energy enumerative amplitude trellis, a bounded-energy and bounded-kurtosis enumerative amplitude trellis, and a Band-trellis used by an ISAC transmitter device according to an embodiment for PCS;

[0066] Fig. 5d shows a diagram illustrating a trade-off between kurtosis and mutual information with shaping for a transmit power and noise variance for geometric and probabilistic shaping;

[0067] Fig. 6 shows a signalling diagram illustrating the exchange of information between a control entity according to an embodiment and an ISAC transmitter device according to an embodiment;

[0068] Fig. 7 shows one MCS index table used by an ISAC transmitter device according to an embodiment for a K-ESS, CK-ESS or a Band-ESS based scheme;

[0069] Figs. 8a and 8b show a first algorithm for enumerative shaping implemented by an ISAC transmitter device according to an embodiment and a second algorithm for enumerative deshaping implemented by an ISAC receiver device; Fig. 9 shows a flow diagram illustrating a method of operating a control entity according to an embodiment for ISAC in a wireless network; and

[0070] Fig. 10 shows a flow diagram illustrating a method of operating an ISAC transmitter device according to an embodiment.

[0071] In the following, identical reference signs refer to identical or at least functionally equivalent features.

[0072] DETAILED DESCRIPTION OF THE EMBODIMENTS

[0073] In the following description, reference is made to the accompanying figures, which form part of the disclosure, and which show, by way of illustration, specific aspects of embodiments of the present disclosure or specific aspects in which embodiments of the present disclosure may be used. It is understood that embodiments of the present disclosure may be used in other aspects and comprise structural or logical changes not depicted in the figures. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present disclosure is defined by the appended claims.

[0074] For instance, it is to be understood that a disclosure in connection with a described method may also hold true for a corresponding device or system configured to perform the method and vice versa. For example, if one or a plurality of specific method steps are described, a corresponding device may include one or a plurality of units, e.g. functional units, to perform the described one or plurality of method steps (e.g. one unit performing the one or plurality of steps, or a plurality of units each performing one or more of the plurality of steps), even if such one or more units are not explicitly described or illustrated in the figures. On the other hand, for example, if a specific apparatus is described based on one or a plurality of units, e.g. functional units, a corresponding method may include one step to perform the functionality of the one or plurality of units (e.g. one step performing the functionality of the one or plurality of units, or a plurality of steps each performing the functionality of one or more of the plurality of units), even if such one or plurality of steps are not explicitly described or illustrated in the figures. Further, it is understood that the features of the various exemplary embodiments and / or aspects described herein may be combined with each other, unless specifically noted otherwise.

[0075] Figure la shows a schematic diagram illustrating a mobile wireless network 100 configured to provide mobile communication services. In an embodiment, the mobile network 100 may be a current or future 3rd Generation Partnership Project (3GPP) mobile network 100. The mobile network 100 comprises a control entity 130, one or more integrated sensing and communication, ISAC, transmitter devices, such as the ISAC transmitter device 110 shown in figure la, for sensing and data communication with one or more ISAC receiver devices, such as the ISAC receiver device 120 shown in figure la. In an embodiment, the control entity 130 may be implemented by a network entity or a network function, such as a sensing function, SF, of the mobile network 100. In an embodiment, the control entity 130 may be implemented as a sensing unit. SU, as part of or close to the RAN of the mobile network 100. In an embodiment, the ISAC transmitter device 110 may be implemented as a base station 110 or a distributed radio unit 110 and the ISAC receiver device 120 may be implemented as a user equipment, UE, 120. In an embodiment, the ISAC receiver device 120 may be a communication receiver or a sensing receiver.

[0076] As will be appreciated, Integrated Sensing and Communication, ISAC, is a key technology, for instance a communication network in the future. The integration of both technologies enables, for example, a more efficient use of the spectrum, opportunities for new services for the operators, end users, and the like. In an embodiment, the ISAC transmitter device 110 is configured to implement one or more of the following sensing tasks: target detection; target tracking; target monitoring; target identification; environment sensing, in particular imaging; and / or environment monitoring (e.g. weather). As illustrated in figure la, the ISAC transmitter device 110 comprises processing circuitry 111 and a communication interface 113, for instance, a transceiver unit 113. The processing circuitry 111 may be implemented in hardware and / or software. The hardware may comprise digital circuitry, or both analog and digital circuitry. Digital circuitry may comprise components such as application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), digital signal processors (DSPs), or one or more general-purpose processors. Moreover, the ISAC transmitter device 110 may comprise a memory 115 configured to store executable program code which, when executed by the processing circuitry 111, causes the ISAC transmitter device 110 to perform the functions and operations described herein.

[0077] Likewise, the ISAC receiver device 120 may comprise processing circuitry 121 and a communication interface 123, for instance, a transceiver unit 123. The processing circuitry 121 may be implemented in hardware and / or software. The hardware may comprise digital circuitry, or both analog and digital circuitry. Digital circuitry may comprise components such as application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), digital signal processors (DSPs), or one or more general-purpose processors. Moreover, the ISAC receiver device 120 may comprise a memory 125 configured to store executable program code which, when executed by the processing circuitry 121, causes the ISAC receiver device 120 to perform the functions and operations described herein.

[0078] Likewise, the control entity 130 may comprise processing circuitry 131 and a communication interface 133, for instance, a transceiver unit 133. The processing circuitry 131 may be implemented in hardware and / or software. The hardware may comprise digital circuitry, or both analog and digital circuitry. Digital circuitry may comprise components such as application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), digital signal processors (DSPs), or one or more general-purpose processors. Moreover, the control entity 130 may comprise a memory 135 configured to store executable program code which, when executed by the processing circuitry 131, causes the control entity 130 to perform the functions and operations described herein.

[0079] Figure lb shows a schematic diagram illustrating a sensing task for sensing a target 140 in the mobile network 100 using the ISAC transmitter device 110 according to an embodiment and an ISAC receiver device 120. In the exemplary scenario illustrated in figure la the ISAC transmitter device 110 transmits a signal to perform sensing, which is received by the ISAC receiver device 120 directly and / or reflected by the target 140. Based on the received signals, the target 140 may be detected and sensed. As will be appreciated, the detection performance may be highly dependent on the ambiguity function of the signals. The performance may be measured, for instance, by the detection probability and / or the false alarm probability. Depending on the target 140, the use case and the requirement, a different trade-off between these two quantities may be more suitable.

[0080] As will be described in more detail below, the control entity 130 illustrated in figure la is adapted to configure a constellation shaping scheme of a modulation and coding scheme, MCS, implemented by the ISAC transmitter device 110 illustrated in figure la and the ISAC transmitter device 110 is adapted to communicate with the ISAC receiver device 120 using the configuration of the constellation shaping scheme of the MCS defined by the control entity 130. In an embodiment, the constellation shaping scheme may be a probabilistic constellation shaping scheme, a geometric constellation shaping scheme or a combination of a probabilistic and geometric constellation shaping scheme. As will be appreciated, while a probabilistic constellation shaping scheme may adjust the probability distribution, i.e. the probability of the constellation points within the complex I / Q plane (for instance starting from a uniform distribution), geometric constellation shaping may adjust the position of one or more constellation points within the complex I / Q plane.

[0081] Figures 2a and 2b show schematic diagrams illustrating variants of the embodiment of figure la. In the embodiment of figure 2a the ISAC transmitter device 110 is adapted to forward the configuration of the probabilistic shaping scheme of the MCS defined by the control entity 130 to the ISAC receiver device 120. In the embodiment of figure 2b an IS AC transmitter device 150 comprises the control entity 130 and the ISAC transmitter device 110 of figures la and 2a. Before describing more detailed embodiments of the control entity 130 and the ISAC transmitter device 110, 150 in the following some technical background on constellation shaping schemes will be described, which may be used according to embodiments disclosed herein.

[0082] As will be appreciated, probabilistic constellation shaping modifies the probabilities of the points in a constellation. Figures 3a and 3b show two exemplary 64-QAM symbol distributions, namely a uniform distribution (figure 3a), and a shaped distribution (figure 3b). In the article “Reshaping the ISAC Trade-off Under OFDM Signalling: A Probabilistic Constellation Shaping Approach”, Z. Du, F. Liu, Y. Xiong, T. X. Han, Y. C. Eldar, S. Jin, arXiv:2312.15941vl, which is fully included herein by reference, the fourth moment, i.e. kurtosis of signal is limited to optimize the average ambiguity function for detecting a target. Figure 3c shows the autocorrelation for various symbol distributions. Depending on the symbol distribution, the height of the autocorrelation’s side-lobe changes. It is the lowest for PSK modulations. The height of the side-lobe for shaped 64-QAM symbol distribution can be varied within the range shown by the arrow indicated in figure 3c.

[0083] Figures 4a and 4b show diagrams illustrating two exemplary 16 point symbol distributions without and with geometric shaping, GS. As already described above, in an embodiment, the constellation shaping scheme configured by the control entity 130 may be a probabilistic constellation shaping scheme, a geometric constellation shaping scheme or a combination of a probabilistic and geometric constellation shaping scheme.

[0084] Geometric constellation shaping for ISAC has been disclosed in B. Geiger, F. Liu, S. Lu, A. Rode, and L. Schmalen, “Joint Optimization of Geometric and Probabilistic Constellation Shaping for OFDM-ISAC Systems,” arXiv:2501.11583vl, which is fully incorporated herein by reference and where an autoencoder (AE) framework has been proposed for optimizing the symbol distribution.

[0085] As will be appreciated, geometric constellation shaping modifies the position of the points in the constellation. Figures 4a and 4b show two exemplary 16-point symbol distributions with a uniform distribution (figure 4a) and with a geometrically shaped distribution (figure 4b). Geometric constellation shaping leads to non-uniform distributions. Geometric constellation shaping has been implemented for communications in ATSC 3.0 and some DVB standards. As already described above, according to embodiments disclosed herein geometric constellation shaping and probabilistic constellation shaping may also be combined to a joint constellation shaping. According to an embodiment an autoencoder framework may also be applied to optimize the symbol distribution for joint probabilistic and geometric constellation shaping.

[0086] For symbol distributions with a high kurtosis, it is more likely that the detector mistakes a strong side-lobe with a weak target, as illustrated in the article “Reshaping the ISAC Trade-off Under OFDM Signalling: A Probabilistic Constellation Shaping Approach” (where a SO-CFAR detector is used), because a weak target’s correlation peak may lie above the detector’s threshold for symbol distributions with a small kurtosis, and the weak target is detected, while for symbol distributions with a large kurtosis, the correlation peak may lie below the detector’s threshold, and the weak target is not detected.

[0087] As may be taken from the example above, optimal symbol distributions for the sensing problem may minimize the kurtosis. Uniform PSK constellations minimize the kurtosis for example. Such symbol distributions may be advantageously used in a sensing only scenario. As will be appreciated, the optimal input symbol distribution for communication, which achieves the channel capacity for communication over an AWGN channel, is a Gaussian distribution. For ISAC, where the communication signal is also used for sensing, PSK constellations may be suboptimal, since the achievable communication rate is lower, because they do not exploit varying the complex amplitude. Therefore, there is a trade-off in ISAC which constellation is most suitable and should be used.

[0088] This trade-off in the example above between the achievable rate and detection probability, which depends on the Kurtosis c0, is illustrated in the article “Reshaping the ISAC Trade-off Under OFDM Signalling: A Probabilistic Constellation Shaping Approach”. For small values of c0, the achievable information rate is smaller, while the detection probability Pd is larger. As c0increases, the achievable information rate increases and the detection probability decreases. As can be taken from this relationship, there are gains for probabilistic shaping in ISAC systems.

[0089] As will be described in more detail in the following, the control entity 130 illustrated in figures la, 2a and 2b is configured to adapt the constellation shaping scheme used by the ISAC transmitter device 130 and / or the ISAC receiver device 120 depending on the sensing task and / or communication task indicated by a task indication. More specifically, the control entity 130 is configured to obtain a task indication indicative of a sensing task and / or a communication task in the wireless network 100. In an embodiment, the sensing task and / or communication task may comprise one or more of the following tasks: target detection; target tracking; target monitoring; target identification; environment sensing, in particular imaging; and / or environment monitoring (e.g. weather). In an embodiment, the control entity 130 may receive the task indication from a core network entity of the mobile wireless network 100.

[0090] The control entity 130 is further configured to generate, based on the task indication, one or more ISAC configuration parameters for configuring a constellation shaping scheme of a modulation and coding scheme, MCS, implemented by the ISAC transmitter device 110 and / or the ISAC receiver device 120. Moreover, the control entity 130 is configured to provide the one or more ISAC configuration parameters to the ISAC transmitter device 110 and / or to the ISAC receiver device 120. As already described above, in an embodiment, the constellation shaping scheme configured by the control entity 130 may be a probabilistic constellation shaping scheme, a geometric constellation shaping scheme or a combination of a probabilistic and geometric constellation shaping scheme, i.e. a joint probabilistic and geometric constellation shaping scheme.

[0091] The communication interface 113 of the ISAC transmitter device 110 is adapted to receive the one or more ISAC configuration parameters from the control entity 130, wherein, as already described above, the one or more ISAC configuration parameters are based on the task indication indicative of a sensing task and / or a communication task in the ISAC wireless network 100. The processing circuitry 111 of the ISAC transmitter device 110 is adapted to configure a constellation shaping scheme of a modulation and coding scheme, MCS, implemented by the ISAC transmitter device 110 based on the one or more ISAC configuration parameters. The communication interface 113 of the ISAC transmitter device 110 is further configured to transmit one or more ISAC signals to the ISAC receiver device 120 using the configuration of the constellation shaping scheme of the MCS defined by the one or more ISAC configuration parameters.

[0092] In an embodiment, the control entity 130 is configured to determine one or more desired sensing performance measures based on the task indication. In an embodiment, the one or more desired sensing performance measures comprise a desired sensing detection accuracy and / or an indication of a desired maximum sensing false alarm probability. In an embodiment, the control entity 130 is configured to generate, based on the task indication, the one or more ISAC configuration parameters for configuring the constellation shaping scheme of the MCS implemented by the ISAC transmitter device 110 by determining one or more moments of a symbol distribution that achieves the one or more desired sensing performance measures and determining the one or more ISAC configuration parameters based on the one or more moments of the symbol distribution. In an embodiment, the one or more moments of the symbol distribution comprise a kurtosis and / or a variance of the symbol distribution.

[0093] Thus, embodiments described herein allow adapting the constellation shaping scheme depending on the sensing task via the one or more IS AC configuration parameters for the shaping strategy that is determined by the controller entity 130. These ISAC configuration parameters are communicated to the ISAC transmitter device 110 and / or the ISAC receiver device 120 for configuring their respective encoder and decoder.

[0094] As already described above, in an embodiment, the constellation shaping scheme of the MCS implemented by the ISAC transmitter device 110 configured by the control entity 130 may be a probabilistic constellation shaping scheme, a geometric constellation shaping scheme or a combination of a probabilistic and geometric constellation shaping scheme, i.e. a joint probabilistic and geometric constellation shaping scheme. In an embodiment, the probabilistic shaping scheme of the MCS implemented by the ISAC transmitter device 110 may be a probabilistic amplitude shaping scheme.

[0095] In an embodiment, the probabilistic amplitude shaping scheme of the MCS implemented by the ISAC transmitter device 110 may be based on an enumerative sphere shaping, ESS, scheme, a Band-limited enumerative sphere shaping scheme, Band- ESS, and / or a Kurtosis-limited enumerative sphere shaping, K-ESS, scheme, all of which are described in the following in more detail.

[0096] ESS (as disclosed, for instance, in Y. C. Giiltekin, W. J. van Houtum, A. G. C. Koppelaar, and F. M. J. Willems, “Enumerative sphere shaping for wireless communications with short packets,” IEEE Trans. Wireless Commun., vol. 19, no. 2, pp. 1098-1112, Feb. 2020, arXiv: 1903.10244) is an efficient implementation for probabilistic amplitude shaping, especially for short block lengths. ESS enumerates all amplitude sequences of length N by using a trellis. Kurtosis-limited ESS, K-ESS, (as disclosed in Y. C. Giiltekin, A. Alvarado, O. Vassilieva, I. Kim, P. Palacharla, C. M. Okonkwo, and F. M. J. Willems, “Kurtosis-limited sphere shaping for nonlinear interference noise reduction in optical channels,” J. Lightw. Technol., vol. 40, no. 1, pp. 101-112, Jan. 2022, arXiv:2105.14794) and Band-ESS (as disclosed in Y. C. Giiltekin, F. M. J. Willems, and A. Alvarado, “Band-ESS: Streaming enumerative coding with applications to probabilistic shaping,” in Proc. IEEE Global Commun. Conf. (GLOBECOM), Rio de Janeiro, Brazil, Dec. 2022, pp. 3223-3228, arXiv: 2208.07111) have been used in optical channels to control the kurtosis. The kurtosis is an important parameter for the nonlinear interference in the optical fibre channel.

[0097] More specifically, for ESS each amplitude sequence of length N is described by a path though the trellis (as illustrated in figure 5a) from the layer n = 0 to the layer with n = N. The nodes in the graph correspond to the energy of the sequence and the branches correspond to the respective amplitude in the sequence. Given the amplitudes of the real / imaginary part of the constellation, at, and the maximum energy E. a trellis is used to enumerate the sequences in the set: where JI is the amplitude alphabet, which is given by the modulation. For a given modulation and a sequence length N, the parameter E determines the trellis. Further details of ESS are disclosed in Y. C. Giiltekin, W. J. van Houtum, A. G. C. Koppelaar, and F. M. J. Willems, “Enumerative sphere shaping for wireless communications with short packets,” IEEE Trans. Wireless Commun., vol. 19, no. 2, pp. 1098-1112, Feb. 2020, arXiv: 1903.10244, which is fully included herein by reference. Similar to ESS, for K-ESS each amplitude sequence of length N is described by a path through the trellis, but here, the nodes correspond to the energy and kurtosis of the sequence, as illustrated in figure 5b. This is used to limit the kurtosis of the sequences. Given the amplitudes of the real / imaginary part of the constellation, at, a maximum energy E and maximum kurtosis K, a trellis is used to enumerate the sequences in the set:

[0098] As will be appreciated, the parameters E and K determine the trellis for a given sequence length N and given modulation. Further details of K-ESS are disclosed in Y. C. Giiltekin, A. Alvarado, O. Vassilieva, I. Kim, P. Palacharla, C. M. Okonkwo, and F. M. J. Willems, “Kurtosis-limited sphere shaping for nonlinear interference noise reduction in optical channels,” J. Lightw. Technol., vol. 40, no. 1, pp. 101-112, Jan. 2022, arXiv:2105.14794, which is fully included herein by reference. Commun. Conf. (GLOBECOM), Rio de Janeiro, Brazil, Dec. 2022, pp. 3223-3228, arXiv: 2208.07111, which is fully included herein by reference.

[0099] It has been realized that the maximum kurtosis on the real and imaginary parts may be suboptimal compared to a maximum kurtosis on the complex symbol distribution, because it converges to a square instead of a sphere as the kurtosis constraints become stricter when a continuous constellation is considered. This also implies that with separate shaping of the real and imaginary parts, it is difficult to realize a symbol distribution as shown in figure 3b that has a circular shape. More specifically, with separate shaping of the real and imaginary parts, only symbol distributions, where the probability of each constellation point is the same as the corresponding product of the marginal probabilities on the real and imaginary axis, can be realized.

[0100] To address this issue, according to an embodiment the processing circuitry 113 of the IS AC transmitter device 110 is configured to shape the real and the imaginary part of each complex amplitude jointly, preferably using one of the ESS based schemes described above. However, other shaping techniques may also be used for joint shaping of the real and imaginary parts of the constellation.

[0101] In an embodiment, the processing circuitry 113 of the IS AC transmitter device 110 may be configured to shape the real and the imaginary part of each complex amplitude jointly based on a trellis enumerating the sequences in the following set: wherein C is the alphabet of all symbols in the first quadrant, which is defined by the MCS, E denotes one or the one or more ISAC configuration parameters associated with a variance, i.e. maximum energy, K denotes one of the one or more ISAC configuration parameters associated with the kurtosis, and N denotes a sequence length. This scheme is referred to as Complex valued K-ESS, CK-ESS, herein. As will be appreciated, for a given modulation and a sequence length N, the parameters E and K determines the trellis.

[0102] Figure 6 shows a signalling diagram illustrating the provisioning of the one or more ISAC configuration parameters from the control entity 130 according to an embodiment to the ISAC transmitter device 110 according to an embodiment and the ISAC receiver device 120. In step 601 of figure 6, the control entity 130 receives the task indication indicative of the sensing task from a network entity 160 with a desired detection accuracy and false alarm probability. As already described above, the control entity 130 determines the suitable one or more ISAC configuration parameters for modulation and coding based, for instance, on the autocorrelation function. In steps 603 and 605 of figure 6, the control entity 130 communicates the one or more ISAC configuration parameters to the ISAC transmitter device 110 and the ISAC receiver device 120. As already described above, the ISAC transmitter device 110 uses the one or more ISAC configuration parameters to configure its constellation shaping encoder scheme. Likewise, the ISAC receiver device 120 may use the parameter(s) to configure its constellation shaping decoder scheme.

[0103] In an exemplary scenario, the control entity 130 may receive a task indication indicative of a target detection task with a desired detection and / or false alarm probability. Depending on the detector used, the control entity 130 may determine a suitable kurtosis that achieves the desired detection probability and false alarm probability, as described above in the context of the trade-off between the achievable rate and detection probability. For additive white Gaussian noise, the detection probability is related to an exponential distribution. The kurtosis is then mapped onto the parameter for the modulation and coding scheme. This parameter is then communicated to the ISAC transmitter device 110 and receiver device 120. The ISAC transmitter device 110 uses the parameter to configure, for instance, its ESS based shaping scheme. The ISAC receiver device 120 uses the parameter to configure, for instance, its ESS based shaping scheme.

[0104] In an embodiment, the sequences, the trellis, and / or the parameters for the shaping scheme may be stored in a look-up table and the parameter that is communicated may be an index into the look-up table, similar to the MCS field in DCI, see e.g. TS 38.212. The DCI MCS field consists of 5 bits that are used as index into the MCS index tables, where the table is selected by RRC signalling as described in TS 38.214.

[0105] According to an embodiment, the shaping scheme may be configured adaptively in the following way. The DCI MCS field may be reused to be an index in a new MCS index table that enables choosing between various kurtosis parameters. The new table can be selected by adding a new RRC configuration parameter, which can be a new item in the PDSCH-Config sequence.

[0106] The abridged table shown in figure 7 illustrates how such a new MCS index table could look like for a K-ESS, a CK-ESS, a Band-ESS, and / or a GS based scheme. As will be appreciated, the indices 29 to 31 are reserved, since they are used for retransmission. The amplitude alphabet is given by the modulation order.

[0107] Figure 9 shows a flow diagram illustrating a method 900 for operating a control entity, such as the control entity 130 shown in figure la, for configuring one or more ISAC transmitter devices 110 and / or one or more ISAC receiver devices 120 in a wireless mobile network 100. The method 900 comprises a step 901 of obtaining a task indication indicative of a sensing task and / or a communication task in the wireless network 100. Moreover, the method 900 comprises a step 903 of generating, based on the task indication, one or more ISAC configuration parameters for configuring a constellation shaping scheme of a modulation and coding scheme implemented by the one or more ISAC transmitter devices 110 and / or the one or more ISAC receiver devices 120. The method 900 further comprises a step 905 of providing the one or more ISAC configuration parameters to the one or more ISAC transmitter devices 110 and / or the one or more ISAC receiver devices 120.

[0108] The method 900 can be performed by the control entity 130. Thus, further features of the method 900 result directly from the functionality of the control entity 130 as well as the different embodiments thereof described above and below.

[0109] Figure 10 shows a flow diagram illustrating a method 1000 for operating an integrated sensing and communication, ISAC, transmitter device, such as the ISAC transmitter device 110 shown in figure la, for a wireless mobile network 100. The method 1000 comprises a step 1001 of receiving one or more ISAC configuration parameters from the control entity 130, wherein the one or more ISAC configuration parameters are based on a task indication indicative of a sensing task and / or a communication task in the wireless network 100. Moreover, the method 1000 comprises a step 1003 of configuring a constellation shaping scheme of a modulation and coding scheme, MCS, implemented by the ISAC transmitter device 110 based on the one or more ISAC configuration parameters. The method 1000 comprises further a step 1005 of transmitting one or more ISAC signals to one or more ISAC receiver devices 120 of the wireless network 100 using the configuration of the constellation shaping scheme of the MCS defined by the one or more ISAC configuration parameters.

[0110] The method 1000 can be performed by the ISAC transmitter device 110. Thus, further features of the method 1000 result directly from the functionality of the ISAC transmitter device 110 as well as the different embodiments thereof described above and below.

[0111] The person skilled in the art will understand that the "blocks" ("units") of the various figures (method and apparatus) represent or describe functionalities of embodiments of the present disclosure (rather than necessarily individual "units" in hardware or software) and thus describe equally functions or features of apparatus embodiments as well as method embodiments (unit = step).

[0112] In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus, and method may be implemented in other manners. For example, the described embodiment of an apparatus is merely exemplary. For example, the unit division is merely a logical function division and may be another division in an actual implementation. For example, a plurality of units or components may be combined or integrated into another system, or some features may be ignored or not performed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections may be implemented by using some interfaces. The indirect couplings or communication connections between the apparatuses or units may be implemented in electronic, mechanical, or other forms. The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one position, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments. In addition, functional units in the embodiments of the disclosure may be integrated into one processing unit, or each of the units may exist alone physically, or two or more units may be integrated into one unit.

Claims

CLAIMS1. A control entity (130) for configuring one or more transmitter devices (110; 150) and / or one or more receiver devices (120) for integrated sensing and communication, ISAC, in a wireless network (100), wherein the control entity (130) is configured to: obtain a task indication indicative of a sensing task and / or a communication task in the wireless network (100); generate, based on the task indication, one or more ISAC configuration parameters for configuring a constellation shaping scheme of a modulation and coding scheme, MCS, implemented by the one or more transmitter devices (110; 150) and / or the one or more receiver devices (120); and provide the one or more ISAC configuration parameters to the one or more transmitter devices (110; 150) and / or the one or more receiver devices (120).

2. The control entity (130) of claim 1, wherein the constellation shaping scheme is a probabilistic and / or geometric constellation shaping scheme.

3. The control entity (130) of claim 1 or 2, wherein the control entity (130) is configured to determine one or more desired sensing performance measures based on the task indication.

4. The control entity (130) of claim 3, wherein the one or more desired sensing performance measures comprise a desired sensing detection accuracy and / or an indication of a desired maximum sensing false alarm probability.

5. The control entity (130) of claim 3 or 4, wherein the control entity (130) is configured to generate, based on the task indication, the one or more ISAC configuration parameters for configuring the constellation shaping scheme of the MCS implemented by the one or more transmitter devices (110; 150) and / or the one or more receiver devices (120) by determining one or more moments of a symbol distribution that achieves the one or more desired sensing performance measures and determining the one or more ISAC configuration parameters based on the one or more moments of the symbol distribution.

6. The control entity (130) of claim 5, wherein the one or more moments of the symbol distribution comprise a kurtosis and / or a variance of the symbol distribution.

7. A method (900) of operating a control entity (130) for configuring one or more transmitter devices (110; 150) and / or one or more receiver devices (120) for integrated sensing and communication, ISAC, in a wireless network (100), wherein the method (900) comprises: obtaining (901) a task indication indicative of a sensing task and / or a communication task in the wireless network (100); generating (903), based on the task indication, one or more ISAC configuration parameters for configuring a constellation shaping scheme of a modulation and coding scheme implemented by the one or more transmitter devices (110; 150) and / or the one or more receiver devices (120); and providing (905) the one or more ISAC configuration parameters to the one or more transmitter devices (110; 150) and / or the one or more receiver devices (120).

8. A transmitter device (110; 150) for integrated sensing and communication, ISAC, in a wireless network (100), wherein the transmitter device (110; 150) comprises: a communication interface (113) adapted to receive one or more ISAC configuration parameters from a control entity (130), wherein the one or more ISAC configuration parameters are based on a task indication indicative of a sensing task and / or a communication task in the wireless network (100); and a processing circuitry (111) adapted to configure a constellation shaping scheme of a modulation and coding scheme, MCS, implemented by the transmitter device (110; 150) based on the one or more ISAC configuration parameters; wherein the communication interface (113) is further configured to transmit one or more ISAC signals to one or more receiver devices (120) of the wireless network (100) using the configuration ofthe constellation shaping scheme ofthe MCS defined by the one or more ISAC configuration parameters.

9. The transmitter device (150) of claim 8, wherein the constellation shaping scheme is a probabilistic and / or geometric constellation shaping scheme.

10. The transmitter device (150) of claim 8 or 9, wherein the transmitter device (150) comprises the control entity (130).

11. The transmitter device ( 110; 150) of any one of claims 8 to 10, wherein the transmitter device (110; 150) is configured to provide the one or more ISAC configuration parameters to one or more ofthe receiver devices (120).

12. The transmitter device (110; 150) of any one of claims 8 to 11, wherein the constellation shaping scheme comprises a probabilistic amplitude shaping scheme.

13. The transmitter device (110; 150) of claim 12, wherein the probabilistic amplitude shaping scheme is based on an enumerative sphere shaping scheme, a Band-limited enumerative sphere shaping scheme, or a Kurtosis-limited enumerative sphere shaping scheme or wherein the probabilistic amplitude shaping scheme is generated based on a trellis enumerating the sequences in the following set:wherein C is the alphabet of all symbols in a first quadrant, which is defined by the MCS, E denotes one or the one or more ISAC configuration parameters associated with a variance, K denotes one ofthe one or more ISAC configuration parameters associated with the kurtosis, and N denotes a sequence length.

14. The transmitter device (110; 150) of any one of claims 8 to 13, wherein the transmitter device ( 110; 150) is configured to shape the real and the imaginary part of each complex amplitude jointly.

15. The transmitter device (110; 150) of any one of claims 8 to 11, wherein the constellation shaping scheme comprises a geometric constellation shaping scheme based on a machine learning, ML, optimization, evolutionary algorithms, and / or global optimization techniques.

16. A method ( 1000) of operating a transmitter device (110; 150) for integrated sensing and communication, IS AC, in a wireless network (100), wherein the method (1000) comprises: receiving (1001) one or more IS AC configuration parameters from a control entity (130), wherein the one or more IS AC configuration parameters are based on a task indication indicative of a sensing task and / or a communication task in the wireless network (100); configuring (1003) a constellation shaping scheme of a modulation and coding scheme, MCS, implemented by the transmitter device (110; 150) based on the one or more ISAC configuration parameters; and transmitting (1005) one or more ISAC signals to one or more receiver devices (120) of the wireless network (100) using the configuration of the constellation shaping scheme of the MCS defined by the one or more ISAC configuration parameters.

17. A computer program product comprising a computer-readable storage medium for storing program code which causes a computer or a processor to perform the method (900) of claim 7 or the method (1000) of claim 16 when the program code is executed by the computer or the processor.

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