Method for dynamically allocating transmission power between a plurality of carriers for the implementation of a communication system integrating a radio perception function

Abstract

Method for dynamically allocating transmission power between a plurality of carriers for the implementation of a communication system integrating a radio perception functionality. The invention relates to a method for dynamically allocating, by a transmitting device, transmission power between a plurality of carriers for the implementation of a communication system integrating a radio perception functionality.Power allocation is determined based on a set of parameters including at least: - a parameter (PA1) representing a degree of accuracy associated with the radio perception functionality of the system; - a parameter (PA2) representing a degree of ambiguity associated with the radio perception functionality of the system; - a parameter (PA3) representing a degree of performance associated with a communication functionality of the system, when the radio perception and communication functionalities are implemented jointly within the system. Abbreviated figure: Figure 1.

Description

Title of the invention: Method for dynamically allocating transmission power between a plurality of carriers for the implementation of a communication system integrating a radio perception function. Technical field

[0001] The invention relates to the field of communication systems integrating radio perception functionalities, also called ISAC systems (for "Integrated Sensing and Communication" in English) or integrated communication and detection systems. Previous art

[0002] 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 the use of radio waves transmitted within a communication system not only for establishing communication between devices, but also for obtaining information about the environment of those devices. Radio sensing thus consists, for example, similarly to radar, of obtaining information relating to the presence of objects (in the broadest sense: human beings, 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).

[0003] Many modern wireless networks rely on orthogonal frequency division multiple access (OFDM) techniques, which have the advantage of using The goal is to efficiently utilize 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 different OFDM carriers—becomes critical. In such systems, the requirements for optimal communication performance are likely to conflict with the requirements for optimal radio perception performance. For example, maximizing communication capacity can degrade radio perception accuracy, and vice versa. Therefore, effective power allocation strategies must be identified and implemented to ensure that neither functionality—communication or radio perception—is unduly compromised.

[0004] 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, which aims to optimize the power allocation on OFDM carriers in the presence of constraints on the peak sidelobe level (PSL) of the waveform. More specifically, this method emphasizes minimizing these sidelobes in order to reduce the ambiguity of 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, the... Adherence to 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.

[0005] 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. Summary of the invention

[0006] 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 transmission power, by a transmitting device, 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:

[0007] - a parameter representing a degree of precision associated with said functionality radio perception of said system;

[0008] - a parameter representing a degree of ambiguity associated with said functionality of radio perception of said system;

[0009] - a parameter representing a degree of performance associated with a functionality of communication of said system, when said radio perception and communication functionalities are implemented jointly within said system.

[0010] In this way, unlike existing solutions, a system according to the present technique is based 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, depending on 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 an implementation would compromise the communication functionality too significantly.

[0011] In one embodiment, said method comprises, for a tested power allocation strategy:

[0012] - the verification of a set of comparison conditions including the comparison of said parameter representing a degree of precision, of said parameter representing a degree of ambiguity, and of 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;

[0013] - when the said conditions for comparison of said set are all satisfied, the allocation of 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. In particular, the system can be configured to dynamically allow the joint implementation of the communication and radio perception functionalities once a power allocation strategy guaranteeing sufficient performance of both functionalities across all considered parameters is identified.

[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 so-called direct approach, 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 according to a filling algorithm, and said method further comprises:

[0018] - when said comparison conditions relate to the representative parameter of a degree of precision and on the representative parameter of 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;

[0019] - when one of the said comparison conditions relating to the parameter representative of a degree of precision and on the parameter representative of a degree of ambiguity is satisfied and the other 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 unmet condition; and

[0020] — when at least one intermediate power allocation strategy satisfying the set of 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 at least one of said intermediate power allocation strategies identified;

[0021] — when no satisfactory intermediate power allocation strategy the set of 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 the power allocation strategy obtained in accordance with said filling algorithm.

[0022] 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 considered 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 joint implementation of communication and radio perception functionalities.

[0023] In a particular embodiment, said search includes determining weights associated with said intermediate allocation strategy, by means of a bisection 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.

[0024] In this way, the search is based on an efficient algorithm that allows rapid convergence towards obtaining the optimal weights associated with an intermediate power allocation strategy.

[0025] In a particular embodiment, 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.

[0026] In this way, it is possible to easily estimate the extent to which the implementation of a tested power allocation strategy degrades communication performance, by using a communication performance metric that is easy to obtain and known to be a good indicator in this respect, and by comparing a measured value of this metric for the tested power allocation strategy with a reference value.

[0027] 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.

[0028] 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.

[0029] In a particular embodiment, said system is implemented by multiplexing by orthogonal frequency distribution using said plurality of carriers.

[0030] 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).

[0031] In a particular embodiment, said parameter representing a degree of accuracy associated with said radio perception functionality is a lower bound for estimation. According to a particular feature of this embodiment, said lower bound for estimation is a Cramer-Rao bound.

[0032] In this way, the degree of accuracy associated with the radio perception functionality can be characterized in a simple way, using easily implementable statistical processing techniques.

[0033] 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.

[0034] In this way, the degree of ambiguity associated with the radio perception functionality is also easily characterized.

[0035] 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 function. Such an electronic device comprises at least one processor configured to determine said power allocation as a function of a set of parameters comprising at least:

[0036] - a parameter representing a degree of precision associated with said functionality of radio perception of said system;

[0037] - a parameter representing a degree of ambiguity associated with said functionality of radio perception of said system;

[0038] - a parameter representing a degree of performance associated with a functionality of communication of said system, when said radio perception and communication functionalities are implemented jointly within said system.

[0039] Such an electronic device may, of course, exhibit the various characteristics relating to the dynamic power allocation method according to the invention, which may be combined or considered separately. 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 the implementation of a communication system integrating a radio perception functionality, and are not described in further detail.

[0040] 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.

[0041] 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 their embodiments.

[0042] Such a recording medium can be any entity or device capable of storing the program. For example, the medium can 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.

[0043] 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 is executable remotely. The program according to the invention can, in particular, be uploaded to a network, for example, the Internet.

[0044] The different embodiments mentioned above can be combined with each other for the implementation of the invention. Figures

[0045] 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:

[0046] [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;

[0047] [Fig.2] schematically illustrates a second approach for implementing a dynamic allocation method of transmission power between a plurality of carriers, in another particular embodiment of the proposed technique;

[0048] [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. Detailed description of the invention

[0049] General principle

[0050] The invention described below makes it possible to remedy some of the aforementioned drawbacks.

[0051] According to a first aspect, the present invention relates to a method for 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 sensing functionality ("Integrated Sensing and Communication," or ISAC), in other words, a system in which radio waves are used not only to establish communication between the transmitting equipment and at least one other piece of equipment but also, where appropriate, to obtain more general information about the environment (for example, the environment of this equipment). The present technique thus falls within the field of communications based on multi-carrier modulation and can, in particular, be implemented in a mode of particular realization, in the context of data transmissions based on orthogonal frequency division multiple access techniques (“orthogonal frequency-division multiple access” in English, or OFDM), a pillar of many current wireless communication networks.

[0052] 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 comprising at least:

[0053] - a PA1 parameter representing a degree of precision associated with a functionality radio perception of the system;

[0054] - a PA2 parameter representing a degree of ambiguity associated with said system radio perception functionality;

[0055] - a PA3 parameter representative of 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, of a parameter representing a maximum latency time associated with the communication functionality of the system, or even a combination of such parameters, when said detection and communication functionalities are implemented jointly within said system).

[0056] By "dynamic" allocation, we thus mean in the context of the present 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.

[0057] More particularly, as detailed below and illustrated for example in relation to [Fig. 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:

[0058] - a first operating mode (called ISAC mode, referenced Mod_lSAC on the figures), in which the two functionalities - communication and radio perception - are implemented jointly, when it is determined, by means of the aforementioned PA1, PA2 and PA3 parameters, 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;

[0059] - a second mode of operation (called communication-only mode, referenced Mod_CO on 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 PA1, 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.

[0060] In other words, the present technique makes it possible to evaluate the feasibility of implementing a high-performance radio perception functionality, both in terms of accuracy and minimization of ambiguity, without unduly compromising the performance of the communication functionality. If no solution meeting all these criteria is identified, the system switches to a communication-only mode.

[0061] To this end, in a step 11, for a tested power allocation strategy P^, a verification is carried out on a set of comparison conditions. 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 for the target radio perception accuracy, a predetermined threshold value for the target radio perception ambiguity, and a predetermined threshold value for the target communication performance.

[0062] According to the general principle of the present technique, a power allocation according to the tested allocation strategy Pt is only performed or validated when all the conditions of the comparison set are met (branch B11 of Figure 1). The system is then configured for use in ISAC mode, with joint implementation of the 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^ is not maintained, and preference is given, for example, to the implementation of a strategy optimized for the communication functionality alone, typically a power allocation strategy P^ obtained according to a water-filling algorithm.

[0063] In this context, we now detail the parameters on which constraints are applied for determining an allocation strategy, in various specific embodiments of the present technique. These parameters include, as introduced previously, parameters allowing us to evaluate a degree accuracy and degree of ambiguity associated with 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 allowing evaluation of a degree of performance of the communication functionality that results from the adoption of such a power allocation strategy.

[0064] Evaluation of the degree of ambiguity of radio perception

[0065] 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 "false positive" type - 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.

[0066] The technique presented in the prior art document describes, in particular, a method for determining 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 YPSL that the sidelobe peak level must not exceed, 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, in particular, by the following equation, which is not explained in further detail in the present technique, but which can be seen to depend on the allocation strategy P implemented:

[0067] max | wHp |2 < heS 1SL

[0068] 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.

[0069] Evaluation of the degree of accuracy of radio perception

[0070] Regarding the degree of accuracy associated with said radio perception (in other words, the system's ability to accurately assess various characteristics of an object in the environment, such as typically its position, particularly in terms of distance from the transmitting device), it is proposed, in a particular embodiment of the present technique, to consider a lower bound for estimation. More specifically, one way to assess 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 is. It is also known that to minimize the Cramer-Rao bound for a given bandwidth, it is It is optimal to allocate more power to the edges of the available subcarriers. This can be expressed by the following equation, which, as we can see, depends on the allocation strategy P implemented:

[0071] TK-1( >v

[0072] where K corresponds to the number of subcarriers, and to the subcarrier index.

[0073] Evaluation of the impact of implementing the radio perception functionality on the communication functionality

[0074] In order to evaluate 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 communication functionality of the system, 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 implementation of 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 so-called water-filling algorithm.Thus, according to a particular feature 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 ratio C / Cw, where C is the communication capacity associated with the tested allocation strategy, and Cw is the optimal communication capacity determined using the filling algorithm. The communication performance is then higher the closer the ratio C / Cw is to 1. Alternatively, the difference Cw - C can also be used to evaluate whether the communication functionality remains sufficiently efficient when the tested allocation strategy is implemented; the communication performance is then higher the closer the difference Cw - C is to 0.

[0075] 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 allocation strategy P being tested:

[0076] dC^>yc

[0077] Formulation of the optimization problem

[0078] It follows from the above that the joint implementation of radio perception and communication functionalities within an ISAC system

[0079]

[0080]

[0081]

[0082]

[0083]

[0084]

[0085]

[0086]

[0087] This amounts to identifying a power allocation strategy that maximizes communication capacity (maxC(p; h)) while respecting the following constraints, which are all power functions: k \2 (constraint on the degree of precision of perception) ^k=O ^-2 ) *k- Y CRB radio: the Cramer-Rao limit must be less than a predetermined threshold, in other words the quantity i. K\2 must be greater than a predetermined threshold; 2 M - max | |2 < y (constraint on the degree of ambiguity of radio perception: the peak level of the side lobes must be less than a predetermined threshold ^psl); - C j CWF > y (constraint on the degree of communication performance: the communication capacity must remain at an acceptable level, in other words the C / ratio must not be degraded below a predetermined threshold Vc by the implementation of the radio perception functionality); - possibly with the additional constraint that the total power available at the level of the emitting device must be used. 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. Specific embodiments 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. First approach Within the framework of this initial approach, which can be described as a direct approach and illustrated by Figure 1, it is proposed first to test (or evaluate) the power allocation strategy as described in the document introduced in the prior art. This strategy aims to satisfy a condition on the peak level of the PSL lateral lobes while maintaining maximum communication capacity. Let jPpsLcettestratégie be the strategy, which corresponds to the tested allocation strategy Pt in Figure 1. With such a strategy, the PSL condition < y relates to the degree of ambiguity of perception. radio is verified (since that is precisely the goal sought by the technique described in the prior art document).

[0088] Two conditions therefore remain to be verified, one relating to the parameter representing the degree of accuracy of the radio perception (typically the value of the Cramer-Rao bound), and the other to the parameter representing the degree of communication performance when the Ppstest strategy is implemented. As presented previously, the parameter representing the degree of communication performance can notably take the form of the ratio R between the CPSL communication capacity associated with the candidate allocation strategy being tested and the C'wp communication capacity corresponding to the optimal capacity obtained for an AvF power allocation strategy determined via a filling algorithm: R = CpsL / CWF.

[0089] In a particular embodiment of the proposed technique, the CRB and R values ​​associated with the power allocation strategy ^psLS are therefore determined, in order to verify whether the two remaining conditions R > yc and CRB < Ycrb are or are not met.

[0090] If these two conditions are met, i.e. that the radio perception functionality can be implemented with sufficient accuracy and minimization of ambiguity without significantly degrading the communication functionality, then a dynamic power allocation is applied according to the power allocation strategy j?psl (branch Bll of [Fig.1]), and the system is then allowed to be used in an ISAC mode (Mod_ISAC), i.e. of integrated communication and radio perception with joint implementation of these two functionalities.

[0091] 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 j?wf defined by the filling algorithm, and the system is then permitted to be used only in communication-only mode (Mod_CO).

[0092] 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 which could, for example, satisfy all the parameters at the cost of a degradation of communication capacity remaining within limits considered acceptable (controlled degradation).

[0093] Also, as an alternative, a second approach, illustrated in relation to [Fig.2], is presented below.

[0094] Second approach

[0095] Within this second approach, it is proposed first to test (or try out) the power allocation strategy jPwf determined according to the filling algorithm and then, in certain well-defined situations, to adapt this initial allocation strategy jPwf in order to try to identify an allocation strategy jPint (described as "intermediate," for reasons detailed later in this document) that offers a satisfactory compromise on all parameters (accuracy and minimization of ambiguity in radio perception, communication capacity). As presented previously, the allocation strategy ^vf is associated with a communication capacity optimal (implementing any allocation strategy other than P^ generally results 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 CWF capacity). Therefore, the condition regarding the degree of communication performance is met when the Pwf allocation strategy is implemented (since this is precisely the goal of the filling algorithm).

[0096] In a particular embodiment of the proposed technique, the PSL and CRB values ​​associated with the power allocation strategy Py^ are then determined, in order to check whether the two remaining conditions PLS < y„TC and CRB < y„DD are met or not, in a step 21.

[0097] Different cases are then considered.

[0098] According to a first case (branch B21 of Figure 2), if these two remaining conditions are met (PLS < y and CRB < YCRB), the 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 ^wf power allocation strategy (i.e., according to the filling algorithm), and the system is configured to be used in ISAC mode (Mod_ISAC), that is, integrated radio communication and perception with joint implementation of these two functionalities.

[0099] According to a second case (branch B22 of Figure 2), neither of these two remaining conditions is met (PLS > y and 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 / 'wf (i.e., according to the filling algorithm), with the difference, however, that the system is then configured to be used only in a communication-only mode (Mod_CO - no implementation of the radio perception functionality). Indeed, in such a situation, even if an adaptation of the PWF allocation strategy would improve the situation of one of the two components of radio perception (accuracy or minimization of ambiguity) 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.

[0100] According to a third case (branch B23 of Figure 2), only one of the two remaining conditions is satisfied (PLS < y or CRB < y, but not both). This third case C-ix-D A offers latitude for identifying compromises that could potentially satisfy all the conditions.

[0101] More particularly, if the condition relating to the degree of ambiguity of radio perception PLS < y is satisfied, it is proposed to apply, in a step 22, a bisection search to find the weights associated with an intermediate allocation strategy jPjnt located between the optimal allocation strategy for communication capacity and a Pedges allocation strategy known to be optimal in terms of accuracy (i.e. in terms of minimizing the CRB) of radio perception (without consideration for the aspects degree of ambiguity of radio perception and communication capacity).

[0102] Similarly, if the condition relating to the degree of accuracy of radio perception CRB < VCRB is satisfied, it is proposed to apply, in step 22, a bisection search to find the weights associated with an intermediate allocation strategy Pjnt located between the allocation strategy P^p optimal for communication capacity and an allocation strategy jPpLS-opt known to be optimal in terms of minimizing ambiguity (i.e. minimizing the lateral lobe peak level) of radio perception (without consideration for the accuracy of radio perception and communication capacity aspects).

[0103] Within the framework of this dichotomy 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 located between the Pwf allocation strategy optimized to maximize communication capacity, and another Ppp allocation strategy among the / ^edges allocation strategy optimized to minimize CRB or the PpLS-opt allocation strategy optimized to minimize the peak level of the PLS side lobes.

[0104] More specifically, the power is distributed according to an intermediate allocation strategy, according to the formula "_, / , \ (with Ppr P= ap pR + [l-ajp wF corresponding to Pedges or PLS-optsel°n, which we consider respectively 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 0 that maximizes communication capacity while satisfying the radio perception constraints imposed by the CRB and PLS metrics.

[0105] The advantage of such an algorithm lies in the way it progressively adjusts the weighting value a. Initially, a lower bound bjnf and an upper bound bmp are defined for the weighting value a, and an intermediate value is calculated according to the formula » , b^rbt»f . If the conditions of binf + 2 radio perception (e.g. CRB < yCRB, or PSL < ypSL) are satisfied for this intermediate value, the lower or upper bound is adjusted accordingly, and the process is repeated, thus gradually, but nevertheless rapidly and efficiently, reducing the search interval until convergence to an optimal weighting value.

[0106] At each iteration of the bisection search, the three conditions for an intermediate allocation strategy / 'int thus identified are checked.

[0107] If these three conditions are met (branch B24 of Figure 2) for an allocation strategy thus determined, i.e. that the radio perception functionality can be implemented with sufficient accuracy and minimization of ambiguity without degrading the communication functionality too much, then a dynamic power allocation is applied according to the power allocation strategy jPjnt, and the system is configured to be used in an ISAC mode (Mod_ISAC), i.e. of integrated communication and radio perception with joint implementation of these two functionalities.

[0108] Otherwise (branch B25 of Figure 2), in other words, if at least one of the three conditions is not met, it is considered that the ISAC mode cannot be implemented satisfactorily. Dynamic power allocation is then applied according to the power allocation strategy P^f defined by the filling algorithm, and the system is permitted to be used only in communication-only mode (Mod_CO).

[0109] The present technique thus relates to a new dynamic power allocation strategy which takes into account, on the one hand, constraints relating to both This technique focuses on a degree of precision and a degree of ambiguity minimization to be achieved for the radio perception functionality, as well as constraints on a minimum capacity to be guaranteed for the communication functionality. In particular, it 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 precision or ambiguity minimization of radio perception cannot be met, or when satisfying the constraints on precision or ambiguity minimization of radio perception has an excessive cost in terms of communication capacity, thus preventing unnecessary degradation of communication performance.

[0110] Device

[0111] According to another aspect, the proposed technique also relates to a device for dynamically allocating transmission power 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 method described above in any one of its embodiments. More particularly, such a device comprises at least one processor configured to determine said power allocation as a function of a set of parameters comprising at least:

[0112] - a parameter representing a degree of precision associated with said functionality of radio perception of said system;

[0113] - a parameter representing a degree of ambiguity associated with said functionality of radio perception of said system;

[0114] - a parameter representing a degree of performance associated with a functionality of communication of said system, when said radio perception and communication functionalities are implemented jointly within said system.

[0115] Figure 3 schematically and in a simplified manner represents the structure of such an electronic device in a particular embodiment. The device, according to the proposed technique, comprises, for example, a memory 31 consisting of a buffer memory M, a processing unit 32, equipped, for example, with at least one qP 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.

[0116] 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, for example, measurement data as input E, 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.

[0117] 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 particularly, 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. A method for dynamically allocating, by a transmitting device, 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.

2. Dynamic allocation method according to claim 1, characterized in that it comprises, for a tested power allocation strategy (PT): - the verification of a set of comparison conditions including the comparison of 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, the allocation of said transmission power according to said tested power allocation strategy (PT).

3. Dynamic allocation method according to claim 2, characterized in that it 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 (Avf) obtained in accordance with a filling algorithm.

4. The dynamic allocation method according to claim 2, characterized in said tested power allocation strategy, is a strategy power allocation obtained in accordance with a filling algorithm 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 (^wf) obtained in accordance with said filling algorithm; - when one of said comparison conditions relating to the parameter representing a degree of precision and to the parameter representing a degree of ambiguity is satisfied and the other not, the search for an intermediate power allocation strategy (Piyr) 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 (Pint); — otherwise, the allocation of said transmission power according to the power allocation strategy obtained in accordance with said filling algorithm (PWF).

5. Dynamic allocation method according to claim 4, characterized in that said search comprises the 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. A 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 orthogonal frequency distribution multiplexing 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. Dynamic allocation method according to any one of claims 1 to 10, characterized in that said parameter representing a degree of ambiguity associated with said radio perception functionality is a sidelobe peak level of a waveform generated within said system.

12. A device for dynamically allocating transmission power 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 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.

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

Images