Method and device for dynamically allocating a transmit power among a plurality of carriers for implementing a communication system incorporating a radio sensing feature

Abstract

The invention relates to a method for dynamically allocating, using a transmitter device, a transmit power among a plurality of carriers for implementing a communication system incorporating a radio sensing feature. The power allocation is determined on the basis of a set of parameters comprising at least: - a parameter (PA1) representative of a degree of precision associated with the radio sensing feature of the system; - a parameter (PA2) representative of a degree of ambiguity associated with the radio sensing feature of the system; - a parameter (PA3) representative of a degree of performance associated with a communication feature of the system, when the radio sensing and communication features are jointly implemented in the system.

Description

[0001] DESCRIPTION

[0002] TITLE: Method for dynamically allocating transmission power between a plurality of carriers for the implementation of a communication system integrating a radio perception function

[0003] technical field

[0004] The invention relates to the field of communication systems integrating radio perception functionalities, also known as ISAC systems (for "Integrated Sensing and Communication" in English) or integrated communication and detection systems.

[0005] Previous art

[0006] The development of techniques aimed at merging communication and radio sensing functionalities into a single system (Integrated Sensing and Communication system) offers particularly interesting prospects in the field of wireless networks. More specifically, "integrated radio sensing and communication" refers to using radio waves transmitted within a communication system not only to establish communication between devices, but also to obtain information about the environment surrounding those devices. Radio sensing, for example, similarly to radar, involves obtaining information about the presence of objects (in the broadest sense: humans, animals, plants, vehicles, buildings, etc.).) in the environment of a piece of equipment and to determine characteristics associated with these objects (such as, for example, their positions, whether they are static or moving, their speeds of movement, possibly their shapes, etc.). One of the primary objectives of ISAC technology is to improve spectral and energy efficiency by using a single waveform for the simultaneous implementation of these two functionalities. Such integration is particularly relevant in the context of the development and deployment of new generations of wireless networks designed to meet growing needs in terms of both high-speed communication and perception performance (e.g., object detection).Many modern wireless networks rely on orthogonal frequency-division multiple access (OFDM) techniques, which have the advantage of efficiently utilizing the available frequency spectrum while remaining resistant to interference during data transmission. In the design of integrated radio communication and perception systems, resource allocation—particularly power allocation across the different OFDM carriers—becomes critical. In such systems, the requirements for optimal communication performance can conflict with the requirements for optimal radio perception performance. For example, maximizing communication capacity can degrade radio perception accuracy, and vice versa.Effective power allocation strategies must therefore be identified and implemented to ensure that neither of the two functionalities – communication or radio perception – is unduly compromised.

[0007] In this context, the paper "Peak sidelobe level based waveform optimization for OFDM joint radar-communications" (MF Keskin, RF Tigrek, C. Aydogdu, F. Lampel, H. Wymeersch, A. Alvarado, and FM Willems - 2020 17th European Radar Conference (EuRAD) - IEEE, 2021, pp. 1-4) presents a method for generating a waveform for joint radio perception and communication. This method aims to optimize power allocation on OFDM carriers when constraints are placed on the peak sidelobe level (PSL) of the waveform. More specifically, this method emphasizes minimizing these sidelobes to reduce ambiguity in radio perception."Reducing ambiguity" refers, in particular, to minimizing the risk of confusion that can arise during radio perception, such as the system mistakenly detecting multiple objects in the vicinity of a piece of equipment when only one object is actually present, or the system mistakenly detecting only one object in the vicinity of a piece of equipment when several objects are actually present (for example, because stronger signals mask weaker signals). However, the approach proposed in this document, based on prior art, has some drawbacks.Indeed, while considering performance in terms of minimizing ambiguity is an important aspect of radio perception, it is not sufficient in itself because it does not guarantee the overall accuracy of radio perception—that is, the system's ability to determine, with the smallest possible margin of error, certain characteristics associated with a detected object, such as its position or speed of movement. Furthermore, the resource allocation problem as formulated in this prior art document, based solely on maximizing communication capacity under a constraint on the sidelobe peak level, can lead to the implementation of power allocation strategies associated with communication performance still considered insufficient.In other words, respecting the constraints on the peak level of the side lobes can have a significant cost, resulting in a degradation of communication capacity to a level that is no longer acceptable.

[0008] There is therefore a need for power allocation strategy determination solutions that do not have at least some of these drawbacks of the prior art.

[0009] Summary of the invention

[0010] The present invention proposes a solution to overcome certain drawbacks of the prior art. In one aspect, the present invention relates to a method for dynamically allocating, by a transmitting device, transmission power between a plurality of frequency sub-bands for the implementation of a communication system incorporating a radio perception function.According to the present technique, said power allocation is determined as a function of a set of parameters comprising at least: a parameter representing a degree of accuracy associated with said radio perception functionality of said system; a parameter representing a degree of ambiguity associated with said radio perception functionality of said system; a parameter representing a degree of performance associated with a communication functionality of said system, when said radio perception and communication functionalities are implemented jointly within said system.

[0011] In addition, a communication system operating mode is selected based on a determined power allocation performance evaluated using the parameter set, from among a first operating mode in which the radio perception and communication functionalities are implemented jointly, and a second operating mode in which the communication functionality is implemented without implementing the radio perception functionality.

[0012] In this way, unlike existing solutions, a system according to the present technique relies on a dynamic allocation of power which not only takes into consideration simultaneously the two main components necessary to obtain a high-performance radio perception functionality - namely the achievement of a satisfactory level of accuracy and the minimization of ambiguity below a certain threshold - but which also takes into account the impacts of the implementation of such a radio perception functionality on the performance of the communication functionality.Thus, the present technique offers the possibility of dynamically and differently configuring the system, according to current radio conditions, in particular by deciding for example not to implement or activate the radio perception functionality when it is determined that it is not possible to achieve sufficiently satisfactory performance on this functionality, or that such implementation would compromise the communication functionality too significantly.

[0013] In one embodiment, said method comprises, for a tested power allocation strategy: verifying a set of comparison conditions including comparing said parameter representing a degree of accuracy, said parameter representing a degree of ambiguity, and said parameter representing a degree of performance with respectively a given threshold value of radio perception accuracy, a given threshold value of radio perception ambiguity, and a given threshold value of communication performance; when said comparison conditions of said set are all satisfied, allocating said transmission power according to said tested power allocation strategy.

[0014] In this way, different performance thresholds are set to evaluate the overall performance of a tested power allocation strategy, in terms of the accuracy of the radio perception functionality, the minimization of ambiguity in the radio perception functionality, and the minimum performance to be guaranteed for the communication functionality. Specifically, the system can be configured to dynamically allow the joint implementation of the communication and radio perception functionalities once a power allocation strategy is identified that guarantees sufficient performance for both functionalities across all considered parameters.

[0015] According to a particular feature of this embodiment, said method further comprises, when at least one comparison condition of said set is not satisfied, the allocation of said transmission power according to a power allocation strategy obtained in accordance with a filling algorithm.

[0016] In this way, according to a first approach called direct, simple and quick to implement, the present technique makes it possible to dynamically maintain a minimum guaranteed communication capacity, by switching the system configuration into a communication-only mode, as soon as it is detected that at least one of the required performance conditions - namely the achievement of a satisfactory level of radio perception accuracy, the minimization of radio perception ambiguity below a certain threshold, or the achievement of a communication performance threshold considered sufficient - is not satisfied.

[0017] Alternatively, according to another particular feature of this embodiment, said tested power allocation strategy is a power allocation strategy obtained in accordance with a filling algorithm, and said method further comprises: when said comparison conditions relating to the parameter representing a degree of accuracy and to the parameter representing a degree of ambiguity are both not satisfied, the allocation of said transmission power according to the power allocation strategy obtained in accordance with said filling algorithm;when one of the said comparison conditions relating to the parameter representing a degree of precision and the parameter representing a degree of ambiguity is satisfied and the other is not, the search for an intermediate power allocation strategy between the power allocation strategy obtained in accordance with said filling algorithm and a power allocation strategy known to optimize said parameter associated with the unverified condition; and when at least one intermediate power allocation strategy satisfying all the comparison conditions relating to said parameter representing a degree of precision, said parameter representing a degree of ambiguity, and said performance parameter is identified, the allocation of said transmission power according to one of said at least one identified intermediate power allocation strategy;when no intermediate power allocation strategy satisfying all the comparison conditions relating to said parameter representing a degree of accuracy, said parameter representing a degree of ambiguity, and said performance parameter is identified, the allocation of said transmission power according to the power allocation strategy obtained in accordance with said filling algorithm.

[0018] In this way, according to a second approach that paves the way for finding compromises, the present technique offers a mechanism for searching for and identifying alternative allocation strategies capable of satisfying all the required performance conditions—namely, achieving a satisfactory level of radio perception accuracy, minimizing radio perception ambiguity below a certain threshold, and achieving a communication performance threshold deemed sufficient—at the cost of a degradation in communication performance remaining within limits considered acceptable (controlled degradation). If an acceptable compromise is identified, the system is configured to allow the combined implementation of communication and radio perception functionalities.

[0019] In a particular embodiment, said search includes determining weights associated with said intermediate allocation strategy, by means of a binary search algorithm from weights associated with the power allocation strategy obtained in accordance with said filling algorithm and weights associated with the power allocation strategy known to optimize said parameter associated with the unmet condition.

[0020] In this way, the research relies on an efficient algorithm that allows rapid convergence towards obtaining the optimal weights associated with an intermediate power allocation strategy.

[0021] In a particular embodiment, the parameter representing a degree of performance associated with the communication functionality is determined by comparing the communication capacity associated with the tested power allocation strategy to a reference communication capacity. This allows for a straightforward estimation of the extent to which implementing a tested power allocation strategy degrades communication performance. This can be achieved by using a readily obtainable communication performance metric known to be a reliable indicator and by comparing a measured value of this metric for the tested power allocation strategy with a reference value.

[0022] According to a particular feature of this embodiment, said reference communication capacity corresponds to a communication capacity associated with a power allocation strategy obtained in accordance with a filling algorithm.

[0023] In this way, the reference communication capacity to which the communication capacity obtained for the tested power allocation strategy is compared is a capacity generally considered optimal in that it is close to a maximum achievable communication capacity.

[0024] In a particular embodiment, said system is implemented by orthogonal frequency division multiplexing using said plurality of carriers.

[0025] In this way, the process according to the present technique can be implemented in many modern wireless networks, as well as in new generations of wireless networks (e.g., 6G network).

[0026] In a particular embodiment, the parameter representing a degree of accuracy associated with the radio perception functionality is a lower bound for estimation. According to a particular feature of this embodiment, the lower bound for estimation is a Cramer-Rao bound.

[0027] In this way, the degree of accuracy associated with the radio perception functionality can be characterized simply, using easily implementable statistical processing techniques.

[0028] In a particular embodiment, said parameter representing a degree of ambiguity associated with said radio perception functionality is a peak level of the sidelobes of a waveform generated within said system.

[0029] In this way, the degree of ambiguity associated with the radio perception functionality is also easily characterized. In another aspect, the proposed invention also relates to a device for dynamically allocating transmission power between a plurality of carriers for implementing a communication system incorporating a radio perception functionality.Such an electronic device includes at least one processor configured to determine said power allocation based on a set of parameters including at least: a parameter representing a degree of accuracy associated with said radio perception functionality of said system; a parameter representing a degree of ambiguity associated with said radio perception functionality of said system; a parameter representing a degree of performance associated with a communication functionality of said system, when said radio perception and communication functionalities are implemented jointly within said system.

[0030] The processor is further configured to select a communication system operating mode based on a determined power allocation performance evaluated using the parameter set, from a first operating mode in which the radio perception and communication functionalities are implemented jointly, and a second operating mode in which the communication functionality is implemented without implementing the radio perception functionality.

[0031] Such an electronic device can, of course, exhibit the various characteristics related to the dynamic power allocation method according to the invention, which can be combined or considered individually. Thus, the characteristics and advantages of this device are the same as those of the dynamic power allocation method between a plurality of carriers for implementing a communication system incorporating a radio perception function, and are not described in further detail.

[0032] According to another aspect, the proposed invention also relates to a computer program product downloadable from a communication network and / or stored on a computer-readable medium and / or executable by a microprocessor, comprising program code instructions for the execution of at least one process as described above in any of its embodiments, when this process is executed on a computer.

[0033] The proposed invention also relates to a computer-readable recording medium on which is recorded a computer program comprising program code instructions for executing the steps of a process as described above, in any of its embodiments.

[0034] Such a recording medium can be any entity or device capable of storing the program. For example, the medium may include a storage means, such as a ROM, for example a CD-ROM or a microelectronic circuit ROM, or a magnetic recording means, for example a USB flash drive or a hard drive.

[0035] On the other hand, such a recording medium can be a transmissible medium such as an electrical or optical signal, which can be transmitted via an electrical or optical cable, by radio, or by other means, so that the computer program it contains can be executed remotely. The program according to the invention can, in particular, be uploaded to a network, for example, the Internet.

[0036] The different embodiments mentioned above can be combined with each other for the implementation of the invention.

[0037] Figures

[0038] Other features and advantages of the invention will become more apparent upon reading the following description of a particular embodiment, given by way of simple illustrative and non-limiting example, and the accompanying drawings, among which:

[0039] [Fig 1] schematically illustrates a first approach for the implementation of a dynamic allocation process of transmission power between a plurality of carriers, in a particular embodiment of the proposed technique;

[0040] [Fig 2] schematically illustrates a second approach for the implementation of a dynamic allocation process of transmission power between a plurality of carriers, in another particular embodiment of the proposed technique;

[0041] [Fig 3] describes a simplified architecture of a dynamic allocation device of transmission power between a plurality of carriers for the implementation of an integrated communication and detection system, in a particular embodiment of the proposed technique.

[0042] Detailed description of the invention

[0043] General principle

[0044] The invention described below makes it possible to remedy some of the aforementioned drawbacks.

[0045] According to a first aspect, the present invention relates to a method of dynamically allocating, by a transmitting device, transmission power between a plurality of carriers (i.e., frequency sub-bands) for the implementation of a communication system integrating a radio perception functionality ("Integrated Sensing and Communication" in English, or ISAC), in other words, a system in which radio waves are not only used to establish communication between the transmitting equipment and at least one other piece of equipment but also, where appropriate, to obtain more generally information about the environment (for example, the environment of this equipment).The present technique is thus in the field of communications based on multi-carrier modulation, and can in particular be implemented, in a particular embodiment, in the context of data transmissions based on orthogonal frequency-division multiple access techniques (OFDM), a pillar of many current wireless communication networks.

[0046] According to the general principle of the proposed technique, power allocation is carried out in accordance with an allocation strategy itself determined according to a set of parameters including at least: a parameter PA1 representing a degree of precision associated with a radio perception functionality of the system; a parameter PA2 representing a degree of ambiguity associated with said radio perception functionality of the system;a PA3 parameter representing a degree of performance associated with a communication functionality of the system, when said radio perception and communication functionalities are implemented jointly within said system (such a parameter may in particular be chosen by an operator of the communication network in which the system is implemented, and may for example take the form, by way of illustration and not limitation, of a parameter representing a minimum communication capacity associated with the communication functionality of the system, a parameter representing a maximum latency time associated with the communication functionality of the system, or a combination of such parameters, when said detection and communication functionalities are implemented jointly within said system).

[0047] By "dynamic" allocation, we mean in the context of this technique the consideration of a set of constraints on these different parameters, in order to determine an appropriate power allocation strategy according to the context, that is to say according to the performance conditions sought, both on the communication functionality and on radio perception.

[0048] More particularly, as detailed below and illustrated for example in relation to figure 1 in a particular embodiment, the present technique makes it possible to perform an automatic selection of an operating mode of an integrated radio communication and perception system between: a first operating mode (called ISAC mode, referenced Mod_ISAC on the figures), in which the two functionalities - communication and radio perception - are implemented jointly, when it is determined, by means of the aforementioned parameters PAI, PA2 and PA3, that it is possible to find a compromise guaranteeing sufficient performance both in terms of accuracy and minimization of ambiguity of radio perception on the one hand, and communication capacity on the other;a second mode of operation (called communication-only mode, referenced Mod_CO in the figures), in which only the communication functionality is implemented (and not the radio perception functionality), when it is determined, by means of the aforementioned PAI, PA2 and PA3 parameters, that maintaining the radio perception functionality compromises communication performance too significantly, or that the performance conditions targeted in terms of radio perception cannot be achieved on at least one of the two parameters associated with this functionality.

[0049] In other words, this technique allows us to assess the feasibility of implementing a high-performance radio perception function, both in terms of accuracy and ambiguity minimization, without significantly impacting the performance of the communication function. If no solution meeting all these criteria is identified, the system switches to a communication-only mode.

[0050] To this end, in step 11, for a power allocation strategy of tested power p T, a verification covering a set of comparison conditions is carried out. These comparison conditions include more particularly the comparison of the parameter representing a degree of radio perception accuracy, the parameter representing a degree of radio perception ambiguity, and the communication performance parameter with respectively a predetermined threshold value of targeted radio perception accuracy, a predetermined threshold value of targeted radio perception ambiguity, and a predetermined threshold value of targeted communication performance.

[0051] According to the general principle of this technique, a power allocation according to the tested allocation strategy p Tis performed or validated only when all the conditions of the comparison set are met (branch B11 of Figure 1). The system is then configured to operate in ISAC mode, with joint implementation of radio perception and communication functionalities. Otherwise, when at least one of these comparison conditions is not met (branch B12 of Figure 1), the tested power allocation strategy p T is not sustainable, and preference is given, for example, to implementing a strategy optimized for communication functionality alone, typically a power allocation strategy p WF obtained according to a filling algorithm, better known by the English term "water-filling algorithm".

[0052] In this context, we now detail the parameters on which constraints are applied to determine an allocation strategy in various specific embodiments of the present technique. These parameters include, as previously introduced, on the one hand, parameters for evaluating the degree of accuracy and ambiguity associated with the radio perception functionality when a given (or tested) power allocation strategy is implemented in an integrated radio communication and perception system, and on the other hand, at least one parameter for evaluating the performance level of the communication functionality resulting from the adoption of such a power allocation strategy.

[0053] Evaluation of the degree of ambiguity of radio perception Regarding the degree of ambiguity associated with said radio perception - that is to say the ability of the system to distinguish different objects in its environment, but also to limit the probabilities of detection of the type "false positive" - ​​it is proposed, in a particular embodiment of the present technique, to consider the peak level of the side lobes ("Peak side level" in English, or PSL) of the generated waveform in relation to a tested allocation strategy.

[0054] The technique presented in the document mentioned in the prior art describes, in particular, a way to determine a power allocation strategy that maximizes communication capacity while respecting a constraint imposed on the sidelobe peak level. This constraint takes the form of a predetermined threshold value y PSLthat the peak level of the sidelobes must not exceed a certain limit, in order to prevent, for example, a strong signal from masking weaker signals. As shown in this prior art document, this constraint can be expressed by the following equation, which is not explained in more detail in the present technique, but which can be seen to depend on the allocation strategy p implemented: max|ip| n 2 < y ES PSL

[0055] The notation (i.e., the definition of the different terms of this equation) is not detailed here, but corresponds to that of the prior art document.

[0056] Evaluation of the degree of accuracy of radio perception

[0057] Regarding the degree of accuracy associated with radio perception (in other words, the system's ability to accurately assess various characteristics of an object in the environment, such as its position, particularly its distance from the transmitting device), it is proposed, in a specific embodiment of this technique, to focus on a lower bound for estimation. More specifically, one way to evaluate the maximum accuracy achievable by the system's radio perception functionality is to calculate its Cramer-Rao bound (CRB), the radio perception functionality being more accurate the smaller its Cramer-Rao bound. Furthermore, it is known that to minimize the Cramer-Rao bound for a given bandwidth, it is optimal to allocate more power to the edges of the available subcarriers.This can be translated into the following equation, which we observe depends on the allocation strategy p implemented: where K corresponds to the number of subcarriers, and k to the subcarrier index.

[0058] Evaluation of the impact of implementing the radio perception functionality on the communication functionality

[0059] To assess how the implementation of a given power allocation strategy—also referred to as the tested allocation strategy in this document—is likely to degrade the system's communication functionality, it is proposed, in a particular embodiment, to compare the communication capacity obtained when the tested power allocation strategy is implemented with a reference communication capacity corresponding to an optimal communication capacity achievable in communication-only mode (i.e., without implementing the radio perception functionality). It is known that this optimal communication capacity is that obtained when implementing a power allocation strategy that can be determined using a water-filling algorithm.Thus, according to a particular characteristic of the present technique, the communication performance within the framework of the implementation of a tested power allocation strategy is evaluated by calculating, for example, the C / C ratio. WF , with C the communication capacity associated with the tested allocation strategy, and C WF The optimal communication capacity is determined using the filling algorithm. Communication performance is then all the more important as the C / C ratio increases. WF is close to 1. Alternatively, the gap C WF — C can also be used to assess whether the communication functionality remains sufficiently efficient when the tested allocation strategy is implemented, with communication performance being all the more important as the gap C WF — C is close to 0.

[0060] Thus, the constraint on the degree of communication performance can be translated, for example, by the following equation, from which it follows from the above that it depends on the tested allocation strategy p:

[0061] C / C WF > Y c Formulation of the optimization problem

[0062] It follows from the above that the joint implementation of radio perception and communication functionalities within an ISAC system amounts to identifying a power allocation strategy that maximizes the communication capacity (max C(p; h)) while respecting the following constraints, which are all functions of the power p:

[0063] Sfc=o ( — Pk — XCRB (constraint on the degree of accuracy of radio perception: the Cramer-Rao boundary must be less than a predetermined threshold, in other words the quantity ~ -] Pk must be greater than a predetermined threshold yCRB ) ; max|w^p| 2 < y PSL (constraint on the degree of ambiguity of radio perception: the peak level of the lateral lobes must be below a predetermined threshold y PSL ) ;

[0064] C / C WF > y c (Constraint on the degree of communication performance: communication capacity must remain at an acceptable level, in other words the C / C ratio WF must not be degraded below a predetermined threshold y c by implementing the radio perception functionality); possibly with the additional constraint that the total power available at the transmitting device must be used.

[0065] In the absence of identification of such an allocation strategy, it is considered, within the framework of the present technique, that the joint implementation of radio perception and communication functionalities cannot be carried out satisfactorily, and it is then proposed, in a particular embodiment of the proposed technique, to fall back on a mode of operation of the system in which only one of these two functionalities (communication or radio perception) is implemented.

[0066] Specific embodiments

[0067] Two approaches to determining a dynamic power allocation strategy are described below for the implementation of the proposed technique, which fall within the framework of the general principle and the particular embodiments previously introduced.

[0068] First approach

[0069] Within the framework of this first approach, which can be described as a direct approach and of which Figure 1, already introduced, can serve as an illustration, it is proposed first to test (or try out) the power allocation strategy as described in the document introduced in the prior art, which, it should be recalled, aims to satisfy a condition on the peak level of the PSL sidelobes while maintaining maximum communication capacity. Let p PSL this strategy, which therefore corresponds to the allocation strategy tested p T from Figure 1. With such a strategy, the PSL condition < y PSL relating to the degree of ambiguity of radio perception is verified (since this is precisely the goal sought by the technique described in the prior art document).

[0070] It therefore remains to verify two conditions, one relating to the parameter representing the degree of accuracy of radio perception (typically the value of the Cramer-Rao bound), and the other to the parameter representing the degree of communication performance, when the strategy p PSL is implemented. As presented previously, the parameter representing the degree of communication performance can notably take the form of the ratio R between the communication capacity C PSL associated with the tested candidate allocation strategy p PSL and the communication capacity C WF corresponding to the optimal capacity obtained for a power allocation strategy p WF determined via a filling algorithm: R = C PSL / C WF .

[0071] In a particular embodiment of the proposed technique, the CRB and R values ​​associated with the power allocation strategy p PSLare therefore determined, in order to verify if the two remaining conditions R > y c and CRB < y' CRB are respected or not.

[0072] If these two conditions are met—that is, if the radio perception functionality can be implemented with sufficient accuracy and ambiguity minimization without significantly degrading the communication functionality—then a dynamic power allocation is applied according to the power allocation strategy p. PSL (branch Bll of figure 1), and the system is then authorized to be used in an ISAC mode (ModJSAC), that is, integrated radio communication and perception with joint implementation of these two functionalities.

[0073] Otherwise, in other words, if either of these two conditions is not met (branch B12 of Figure 1), it is considered that the ISAC mode cannot be implemented satisfactorily. Dynamic power allocation is applied according to the power allocation strategy p WF defined by the filling algorithm, and the system is then authorized to be used only in communication-only mode (Mod_CO). 1

[0074] While it has the advantage of being simple and quick to implement, the first approach is described as "direct" in that it does not focus on the search for alternative allocation strategies that could, for example, satisfy all the parameters at the cost of a degradation of communication capacity remaining within limits considered acceptable (controlled degradation).

[0075] Also, as an alternative, a second approach, illustrated in relation to figure 2, is presented below.

[0076] Little approach

[0077] Within this second approach, it is proposed first to test (or try out) the power allocation strategy p WF determined according to the filling algorithm and then, in certain well-identified situations, to proceed with adaptations of this initial allocation strategy p WF in an attempt to identify an allocation strategy p INT (described as "intermediate," for reasons detailed later in this document) which offers a satisfactory compromise across all parameters (accuracy and minimization of ambiguity in radio perception, communication capacity). As presented previously, the allocation strategy p WF is associated with a communication capacity C WFoptimal (the implementation of any allocation strategy other than p WF generally resulting in a decrease in the associated communication capacity: more precisely, although in some cases several optimal solutions may exist, any change in allocation strategy is generally likely to result in a decrease in the associated communication capacity, without the possibility of improvement beyond this optimal capacity C WF ). Also, the condition regarding the degree of communication performance is met when the allocation strategy p WF is implemented (since that is precisely the purpose of the filling algorithm).

[0078] In a particular embodiment of the proposed technique, the PSL and CRB values ​​associated with the power allocation strategy p WF are then determined, in order to verify if the two remaining conditions PLS < y PLSand CRB < YCRB are ou non respected, in step 21.

[0079] We then consider different cases.

[0080] According to a first case (branch B21 of figure 2), if these two remaining conditions are met (PLS < y PLS and CRB < YCRB) / l a Radio perception functionality can therefore be implemented with sufficient accuracy and ambiguity minimization, while maintaining optimal communication capacity. Dynamic power allocation is applied according to the power allocation strategy p WF (i.e. according to the filling algorithm), and the system is configured to be used in an ISAC mode (ModJSAC), i.e. of integrated radio communication and perception with joint implementation of these two functionalities.

[0081] According to a second case (branch B22 of Figure 2), neither of these two remaining conditions is met (PLS > y PLSand CRB > YCRB) - In this second case, as in the first case, it is proposed to apply a dynamic power allocation according to the power allocation strategy p WF (i.e., according to the filling algorithm), with the difference, however, that the system is then configured to be used only in communication-only mode (Mod_CO - no implementation of the radio perception functionality). Indeed, in such a situation, even with an adaptation of the allocation strategy p WF would allow the situation of one of the two components of radio perception (accuracy or minimization of ambiguity) to be improved to the point of satisfying the condition associated with it, it is known that such an improvement would necessarily be at the expense of the other of these two components, which will then never be able to satisfy the condition associated with it.

[0082] According to a third case (branch B23 of Figure 2), only one of the two remaining conditions is satisfied (PLS < y PLS or CRB < YCRB / ma i s P as both). This third case offers latitude for identifying compromises that could potentially satisfy all the conditions.

[0083] More specifically, if this is the condition relating to the degree of ambiguity of radio perception PLS < y PLS which is satisfied, it is proposed to apply, in step 22, a bisection search to find the weights associated with an intermediate allocation strategy p INT situated between the allocation strategy p WF optimal for communication capacity and allocation strategy p edgesknown to be optimal in terms of accuracy (i.e. in terms of minimizing the CRB) of radio perception (without consideration for aspects of degree of ambiguity of radio perception and communication capability).

[0084] Similarly, if the condition relates to the degree of accuracy of radio perception CRB < y CRB which is satisfied, it is proposed to apply, in step 22, a binary search to find the weights associated with an intermediate allocation strategy p INT situated between the allocation strategy p WF optimal for communication capability and a PpLs-opt allocation strategy known to be optimal in terms of minimizing ambiguity (i.e., minimizing the sidelobe peak level) of radio perception (without consideration of radio perception accuracy and communication capability aspects).

[0085] Within the framework of this bisectional search, it is proposed, for example, in a particular embodiment, to implement an algorithm based on the use of a weighting value a (alpha), between 0 and 1, to allocate power according to an allocation strategy situated between the allocation strategy p WF optimized to maximize communication capacity, and another allocation strategy p PR among the allocation strategy p edges optimized to minimize CRB or PpLs-opt allocation strategy optimized to minimize the peak level of PLS ​​side lobes.

[0086] More specifically, power is distributed according to an intermediate allocation strategy, based on the formula p = ap PR + (1 — cc)p WF (with p PR corresponding to Pedges ou(pLs-opt depending on whether we are in the case described previously, where the condition relating to the degree of ambiguity of radio perception is initially satisfied, or in the case described previously, where the condition relating to the degree of precision of radio perception is initially satisfied). The goal is then to find the weighting value a that maximizes communication capacity while satisfying the radio perception constraints imposed by the CRB and PLS metrics.

[0087] The advantage of such an algorithm lies in the way it progressively adjusts the weighting value a. Initially, a lower bound b in f and an upper bound b sup are defined for the weighting value a, and an intermediate value is calculated according to formula b in f + bsu bm f if the radio perception conditions (e.g., CRB < y CRB , ouPSL < y PSL ) are satisfied for this intermediate value, the lower or upper bound is adjusted accordingly, and the process is repeated, thus progressively, but nevertheless quickly and efficiently, reducing the search interval until convergence to an optimal weighting value a.

[0088] At each iteration of the bisection search, the three conditions for an intermediate allocation strategy p are checked. INT thus identified. If these three conditions are met (branch B24 of Figure 2) for an allocation strategy p INT Once this is determined—that is, the radio perception functionality can be implemented with sufficient accuracy and ambiguity minimization without significantly degrading communication functionality—a dynamic power allocation is applied according to the power allocation strategy p.INT and the system is configured to be used in an ISAC mode (ModJSAC), that is, integrated radio communication and perception with joint implementation of these two functionalities.

[0089] Otherwise (branch B25 in Figure 2), in other words, if at least one of the three conditions is not met, the ISAC mode is considered not to be able to be implemented satisfactorily. Dynamic power allocation is then applied according to the power allocation strategy p WF defined by the filling algorithm, and the system is allowed to be used only in a communication-only mode (Mod_CO).

[0090] This technique relates to a new dynamic power allocation strategy that takes into account constraints on both the degree of accuracy and the degree of ambiguity minimization required for the radio perception functionality, as well as constraints on a minimum capacity to be guaranteed for the communication functionality. In particular, this technique allows for the dynamic maintenance of optimal communication capacity by switching the system to a communication-only mode when, as needed, at least one of the constraints on the accuracy or ambiguity minimization of radio perception cannot be met, or when satisfying the constraints on the accuracy or ambiguity minimization of radio perception would have an excessive cost in terms of communication capacity, thus preventing unnecessary degradation of communication performance.

[0091] Device

[0092] In another respect, the proposed technique also relates to a dynamic power allocation device for transmission between a plurality of carriers for implementing a communication system incorporating a radio perception function, in a particular embodiment of the proposed technique. Such an electronic device, implemented for example within a transmitting device, is capable of carrying out the process described above in any of its embodiments.More specifically, such a device includes at least one processor configured to determine said power allocation based on a set of parameters including at least: a parameter representing a degree of accuracy associated with said radio perception functionality of said system; a parameter representing a degree of ambiguity associated with said radio perception functionality of said system; a parameter representing a degree of performance associated with a communication functionality of said system, when said radio perception and communication functionalities are implemented jointly within said system.

[0093] Figure 3 schematically and simply represents the structure of such an electronic device in a particular embodiment. According to the proposed technique, the device comprises, for example, a memory 31 consisting of a buffer memory M, a processing unit 32, equipped, for example, with at least one pP processor, and controlled by the computer program Pg 33, implementing steps of the dynamic allocation process of transmission power, according to at least one embodiment of the invention.

[0094] At initialization, the code instructions of the computer program 33 are loaded into the buffer memory before being executed by the processor of the processing unit 32. The processing unit 32 receives as input E, for example, measurement data by means of which it can determine the values ​​of the parameters representing respectively a degree of precision associated with the radio perception functionality of the system, a degree of ambiguity associated with the radio perception functionality of said system, and a degree of performance associated with the communication functionality of said system.

[0095] Following one of the approaches described above, the microprocessor of the processing unit 32 then carries out the steps of the dynamic power allocation process, according to the instructions of the computer program 33. More specifically, the processing unit 32 evaluates candidate allocation strategies or determines intermediate allocation strategies, in order to deliver as output S a system configuration comprising on the one hand a power allocation strategy to be implemented, and on the other hand an operating mode to be applied, between a first operating mode (called ISAC mode) in which the two functionalities - communication and radio perception - are implemented jointly, and a second operating mode (called communication only mode), in which only the communication functionality is implemented.

Claims

DEMANDS 1. Method for dynamically allocating, by a transmitting device, a transmission power between a plurality of carriers for the implementation of a communication system integrating a radio perception functionality, characterized in that said power allocation is determined as a function of a set of parameters comprising at least: a parameter (PA1) representing a degree of precision associated with said radio perception functionality of said system; a parameter (PA2) representing a degree of ambiguity associated with said radio perception functionality of said system;a parameter (PA3) representing a degree of performance associated with a communication functionality of said system, when said radio perception and communication functionalities are implemented jointly within said system, and in that an operating mode of said communication system is selected based on a performance of said power allocation determined and evaluated by means of said set of parameters, from among a first operating mode in which said radio perception and communication functionalities are implemented jointly, and a second operating mode in which said communication functionality is implemented without implementing said radio perception functionality.

2. A dynamic allocation method according to claim 1, characterized in that it comprises, for a tested power allocation strategy (p T): a verification of a set of comparison conditions including the comparison of said parameter representing a degree of precision, said parameter representing a degree of ambiguity, and said parameter representing a degree of performance with respectively a given threshold value of radio perception precision, a given threshold value of radio perception ambiguity, and a given threshold value of communication performance; when the said comparison conditions of said set are all satisfied, the allocation of said transmission power according to said tested power allocation strategy (p T ).

3. Dynamic allocation method according to claim 1, characterized in that it comprises, when at least one comparison condition of said assembly is not satisfied, the allocation of said transmission power according to a power allocation strategy (p WF) obtained according to a filling algorithm.

4. Dynamic allocation method according to claim 2, characterized in said tested power allocation strategy is a power allocation strategy obtained according to a filling algorithm (p WF ), and in that said process comprises: when said comparison conditions relating to the parameter representing a degree of precision and to the parameter representing a degree of ambiguity are both not satisfied, the allocation of said transmission power according to the power allocation strategy (p WF) obtained in accordance with said filling algorithm; when one of said comparison conditions relating to the parameter representing a degree of precision and the parameter representing a degree of ambiguity is satisfied and the other is not, the search for an intermediate power allocation strategy (P / NT) between the power allocation strategy obtained in accordance with said filling algorithm and a known power allocation strategy to optimize said parameter associated with the unmet condition; and when at least one intermediate power allocation strategy satisfying all the comparison conditions relating to said parameter representing a degree of precision, said parameter representing a degree of ambiguity, and said performance parameter is identified, the allocation of said transmission power according to one of said at least one intermediate power allocation strategy (p / WT) identified; otherwise, the allocation of said transmission power according to the power allocation strategy obtained in accordance with said filling algorithm (p WF ).

5. Dynamic allocation method according to claim 4, characterized in that said search comprises a determination of weights associated with said intermediate power allocation strategy, by means of a binary search algorithm from weights associated with the power allocation strategy obtained in accordance with said filling algorithm and weights associated with the power allocation strategy known to optimize said parameter associated with the unverified condition.

6. Dynamic allocation method according to any one of claims 2 to 5, characterized in that said parameter representing a degree of performance associated with said communication functionality is determined on the basis of a comparison between a communication capacity associated with said tested power allocation strategy and a reference communication capacity.

7. Dynamic allocation method according to claim 6, characterized in that said reference communication capacity corresponds to a communication capacity associated with a power allocation strategy obtained in accordance with a filling algorithm.

8. Dynamic allocation method according to any one of claims 1 to 7, characterized in that said system is implemented by multiplexing by orthogonal frequency distribution using said plurality of carriers.

9. Dynamic allocation method according to any one of claims 1 to 8, characterized in that said parameter representing a degree of accuracy associated with said radio perception functionality is a lower bound for estimation.

10. Dynamic allocation method according to claim 9, characterized in that said lower estimation bound is a Cramer-Rao bound.

11. A dynamic allocation method according to any one of claims 1 to 10, characterized in that said parameter represents a degree of ambiguity associated with said Radio perception functionality is a peak level of the sidelobes of a waveform generated within said system.

12. Dynamic power allocation device for transmission between a plurality of carriers for the implementation of a communication system integrating a radio perception functionality, characterized in that it comprises at least one processor configured to determine said power allocation as a function of a set of parameters comprising at least: a parameter representing a degree of precision associated with said radio perception functionality of said system; a parameter representing a degree of ambiguity associated with said radio perception functionality of said system;a parameter representing a degree of performance associated with a communication functionality of said system, when said radio perception and communication functionalities are implemented jointly within said system, said processor further being configured to select an operating mode of said communication system based on a performance of said power allocation determined and evaluated by means of said set of parameters, from a first operating mode in which said radio perception and communication functionalities are implemented jointly, and a second operating mode in which said communication functionality is implemented without implementing said radio perception functionality.

13. Product computer program downloadable from a communication network and / or stored on a computer-readable medium and / or executable by a processor, characterized in that it includes program code instructions for the execution of a method according to any one of claims 1 to 11, when executed by a processor of a transmitting device.

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