Method of joint sensing / localization and communication using backscatters via OTSM signaling

Abstract

This invention introduces a novel joint sensing / localization and communication (6) scheme employing backscatter devices (1) and OTSM (Orthogonal Time Sequency Multiplexing Modulation) as waveform. The primary objective is to jointly communicate and sense and achieve accurate UT localization by extracting the environmental information such as range, velocity, and angle, utilizing the already deployed backscatter with minimum system complexity, cost, with relaxed constraints such as synchronization and longer switching time. Integrating both sensing (5) and communication (6) within the same resource grid (time- frequency) and with dense connectivity of backscatter devices (1) enables to incorporate new set of services such as high accuracy localization while communicating.

Description

[0001] METHOD OF JOINT SENSING / LOCALIZATION AND COMMUNICATION USING BACKSCATTERS VIA OTSM SIGNALING

[0002] Technical Field:

[0003] This invention relates to a method of joint sensing / localization and communication using backscatters via OTSM signaling that can be applicable in industrialization, with a diverse range of potential applications.

[0004] State of The Art:

[0005] A new set of diverse requirements and metrics has been introduced for various application classes, beginning with 5G and extending beyond, backscatter communication, a novel technology under investigation by 3GPP, stands out due to its characteristics as ultra-low power devices, providing cost-effective solutions for a range of services and use cases with ultra-low complexity and power consumption. Positioning is a crucial application that has attracted considerable interest in the context of backscatter communication. However, its implementation poses notable challenges, including direct link interference (DLI), optimizing spectrum and power efficiency, ensuring robust synchronization, achieving simple modulation in the time domain, switching times / switching rate, and maintaining overall cost-effectiveness. Addressing these issues is pivotal for unlocking the full potential of backscatter technology in providing high sensing performances and accurate and efficient location awareness services in addition to communication.

[0006] Based on the information described above, localization has been extensively explored within the realms of backscatter and loT (Internet of Things), aiming to localize either a mobile tag or a transmitter using backscatter devices. The literature presents diverse techniques, wireless technologies, and mechanisms for localization services, be it IPS (Indoor Positioning System) or OPS (Outdoor Positioning System). These approaches address challenges related to channel effects, interferences, and errors in accuracy range. In [1], the author introduces WiTag to localize backscatter devices by jointly estimating the Angle of Arrival (AoA) and Time-of-Flight (ToF), leveraging the Channel State Information (CSI) of different paths. To mitigate interference from Direct Link Interference (DLI), the author proposes shifting the backscatter signal to a nonoverlapping channel with the excitation WIFI signal.

[0007] Another study [2] examines the work done in [3], which he considered a smart home scenario involving a WiFi AP, multiple static tags, and a mobile robot. The WiFi AP serves as an excitation source for BackCom, and the robot receives BackCom signals for self-localization using embedded sensors. Improved accuracy is achieved using a receiver with a circular antenna array, enabling AoA measurements in [0, 360] degrees which is an extension to the previous work done in [1], SLAM (simultaneous localization and mapping) algorithm is also used which works in an environment without prior knowledge of the site or positions. This enhanced localization benefits both the robot and the ambient WiFi system, as the robot acts as an active relay, extending coverage. To address interference, the author suggests relocating the backscattered signal to a channel where it doesn't overlap with the excitation WIFI signal.

[0008] In another study [4], the author employed Ultra-Wideband (UWB) Radio Frequency Identification (RFID) for tag localization within an indoor environment. The chosen metric for localization was Time Difference of Arrival (TDoA), and the author applied lateration techniques for the localization process.

[0009] Another study in [5] summarizes the work done in [6], in which the author utilizes LoRa transceivers to transmit an RF signal by modulating the received signal. This system comprises multiple LoRa receivers deployed in different rooms, a LoRa transmitter at a central point (reference point), and the backscatter device carried by the object. The RSS (received signal strength) values are compared between all the receivers to determine the position of the LoRa backscatter devices, whereas machine learning enhances the system performance, this system achieved a localization accuracy of 89.7% in a real-life scenario. Finally, authors in [7, 8, 9, 10] provide a comprehensive summary of measurement techniques for localization, both indoors and outdoors. These techniques include signalbased approaches (RSSI, CSI, RSRP, RSRQ), angle- and direction-based methods (AoA, DoA, ADoA), distance-based techniques (PoA, PDoA), time-based methods (ToF, ToA, TDOA, RtoF, RTT), fingerprinting, and global Navigation Satellite System (GNSS). These techniques are compatible with various technologies, including RF technologies (WIFI, cellular LoRA, RFID, Bluetooth, ZigBee), satellite technologies, and optical technologies (visible light). These models can be used in an environment with prior knowledge of the site and position or without such as SLAM (simultaneous localization and mapping) which involves building a map of the environment while simultaneously determining the location of the moving transmitter within that map which can be classified into two categories filtering and smoothing. For the first one the state is estimated on the start up with the latest measurements and for the second one the full trajectory can be estimated based on the complete set of measurements

[0011] ,

[0010] The existing solutions for localizing mobile transmitters or backscatter devices have explored various waveforms, including chirp signals (such as LoRA) and OFDM (used in WIFI and cellular communication) and RFID. These solutions leverage different metrics for localization, encompassing signal-based parameters, angle and directionbased techniques, and time-based methods, hence distance-based techniques.

[0011] To address challenges related to interference, particularly from the direct link between the transmitter and the receiver, a common strategy involves redirecting the backscattered signal to a different channel.

[0012] While the previous solutions explored localization services through various key performance indicators and technologies, they exhibit certain drawbacks:

[0013] 1) OFDM based localization:

[0014] - Strict frequency synchronization requirement: OFDM, employing orthogonal subcarriers in the frequency domain, demands strict synchronization. - Spectrum inefficiency: Shifting the backscattered signal to a different channel to mitigate interference introduces spectrum inefficiency, affecting overall performance.

[0015] 2) LoRa based localization:

[0016] - Compatibility issues: LoRa is not compatible with conventional equipment and technologies like cellular and Wi-Fi standards.

[0017] - Dependency on dedicated RF source: Implementation requires a dedicated RF source, adding cost to the system.

[0018] 3) RFID based localization:

[0019] - Requires dedicated RF infrastructure.

[0020] - Suffers from limited communication range.

[0021] - Requires strict time synchronization.

[0022] Overall, the different solutions provided doesn’t explore the full potential of backscatter communication such as integrating both sensing capabilities and communication.

[0023] As a result, a new method is needed that can overcome these mentioned disadvantages to OTSM based sensing / localization and communication using backscattering technology, which mitigates interference, power efficiency, robustness to synchronization and flexibility in communication and optimizes the overall performance of the localization system.

[0024] References:

[0025] [1]: Kotaru, M., Zhang, P. and Katti, S., 2017, November. Localizing low-power backscatter tags using commodity WiFi. In Proceedings of the 13th International Conference on emerging Networking Experiments and Technologies (pp. 251-262).

[0026] [2]: Jiang, T., Zhang, Y., Ma, W., Peng, M., Peng, Y., Feng, M. and Liu, G., 2023. Backscatter Communication Meets Practical Battery-Free Internet of Things: A Survey and Outlook. IEEE Communications Surveys & Tutorials.

[0027] [3]: Zhang, S., Wang, W., Tang, S., Jin, S. and Jiang, T., 2020. Robot-assisted backscatter localization for loT applications. IEEE Transactions on Wireless Communications, 79(9), pp.5807-5818. [4] Pannuto, P., Kempke, B. and Dutta, P., 2018, April. Slocalization: Sub-uW ultra wideband backscatter localization. In 2018 17th ACM / IEEE International Conference on Information Processing in Sensor Networks (IPSN) (pp. 242-253). IEEE.

[0028] [5] Jiang, T., Zhang, Y., Ma, W., Peng, M., Peng, Y., Feng, M. and Liu, G., 2023. Backscatter Communication Meets Practical Battery-Free Internet of Things: A Survey and Outlook. IEEE Communications Surveys & Tutorials.

[0029] [6] Lazaro, A., Lazaro, M. and Villarino, R., 2021. Room-level localization system based on LoRa backscatters. IEEE Access, 9, pp.16004-16018.

[0030] [7]: Billa, A., Shayea, I., Alhammadi, A., Abdullah, Q. and Roslee, M., 2020, November. An overview of indoor localization technologies: Toward loT navigation services. In 2020 IEEE 5th International Symposium on Telecommunication Technologies (ISTT) (pp. 76-81). IEEE.

[0031] [8]: Asaad, S.M. and Maghdid, H.S., 2022. A comprehensive review of indoor / outdoor localization solutions in loT era: Research challenges and future perspectives. Computer Networks, 212, p.109041.

[0032] [9]: Zafari, F., Gkelias, A. and Leung, K.K., 2019. A survey of indoor localization systems and technologies. IEEE Communications Surveys & Tutorials, 27(3), pp.2568- 2599.

[0033]

[0010] Kim Geok, T., Zar Aung, K., Sandar Aung, M., Thu Soe, M., Abdaziz, A., Pao Liew, C., Hossain, F., Tso, C.P. and Yong, W.H., 2020. Review of indoor positioning: Radio wave technology. Applied Sciences, 11(1), p.279.

[0034]

[0011] Xuexi, Z., Guokun, L., Genping, F., Dongliang, X. and Shiliu, L., 2019, July. SLAM algorithm analysis of mobile robot based on lidar. In 2019 Chinese Control Conference (CCC) (pp. 4739-4745). IEEE.

[0035] Description of The Invention:

[0036] The purpose of the invention is to revolutionize and enhance the field of backscatter technology by exploiting the features of OTSM to support joint sensing / localization and communication. The invention aims to address existing challenges and limitations in accurate localization services, providing a robust and efficient solution for various applications. By leveraging the unique characteristics of OTSM, such as its interference- resistant nature, extended switching time, and low power requirements, the invention strives to overcome obstacles associated with spectrum efficiency, strict synchronization, and interference in backscatter communication. The ultimate goal is to improve the accuracy, reliability, and cost-effectiveness of sensing / localization services, opening new possibilities for applications in diverse fields, including indoor and outdoor positioning systems, smart homes, loT deployments, and beyond in which the sensing information can be used for different services including navigation, tracking, monitoring, etc.

[0037] The invention tackles a range of technical challenges in backscatter technology, offering innovative solutions. These include interference management through Orthogonal Time Sequency Multiplexing (OTSM), spectrum inefficiency challenges and integrating both sensing / localization with communication to the solution overcomes the traditional approach design which consider only communication as consequence the overall system performance is enhanced, the invention utilizes unique sequences of Walsh Hadamard for each tag, optimizing usage and eliminating separate channel allocations to mitigate the direct link interference (DLI), our solution offers low switching rate hence it decreases the duty cycle of the backscatter device and extend its lifetime, distinguishing it from previous techniques like CDMA or OFDM as it requires high switching rate that should match with the chip duration Tc or the BW respectively. The use of OTSM signals contributes to power efficiency as the data modulation requires only (+1,-1), With an extended switching time based on Walsh Hadamard, the solution enable also robustness to strict synchronization as it offers flexibility to strict synchronization. OTSM's exploitation of the delay and sequency domain offers us flexibility in resources management for both communication and backscatter such as multiplexing more backscatter devices in these two domains within the same physical resources (timefrequency). The low power of backscattered signals ensures minimal interference and heightened power efficiency. Accurate sensing / localization using different metrics, aligned with standards, further solidify the invention's effectiveness. Overall, the simplicity of the modulation scheme based on Walsh Hadamard underscores the invention's cost-effectiveness compared to prior solutions. The invention offers the following advantages to realize all the objectives mentioned above and which will emerge from the detailed description below:

[0038] 1) No interference between the direct link and the backscattered signal at the receiver side: This advantage arises from the separability of the OTSM signal of the transmitter and the backscattered signal in the delay-sequency domain.

[0039] 2) Support of interference free multi-connectivity: To avoid interference from multiple concurrently backscattering tags as well with the direct link, there is no need to allocate a different channel for each backscatter. Instead, we provide each tag with a unique sequence of Walsh Hadamard that is orthogonal and separable at the receiver side.

[0040] 3) Enabling simultaneous high data rate transmission (at the communication nodes) and low-rate modulation (at the backscatter): Broadband transmission is important to provide high data rates from the communication perspective and fine range resolution from a sensing perspective. However, the low-complex backscatter devices cannot modulate such broadband signals due to its limitations and constraints such as power. In the disclosed invention, OTSM carriers can be modulated via backscatters in a longer switching time (low switching rate) allowing while ensuring broadband communication and super resolution sensing.

[0041] 4) Dense connectivity: The approach explores the delay and sequency domain, allowing for the multiplexing of more backscatters if needed without affecting the overall physical resource (time-frequency).

[0042] 5) Measurements efficiency: The low power of backscattered signal ensures that in instances where one backscatter reflects the signal of other backscatters, the power remains negligible at the receiver side which ensure the correctness of the measurements at the receiver side.

[0043] 6) Power-efficiency of BS with OTSM signal: The use of an OTSM signal ensures power efficiency for the backscatter devices.

[0044] 7) Backscatters: the backscatter devices can be used for both communication and sensing based on OTSM. 8) Accurate localization with a large number of backscatter devices:

[0045] - Utilizing a large number of backscatters for sensing / Localization improves accuracy by decreasing the error probability. The metric used can be based on standard metrics as well as novel.

[0046] - The receiver can be either a single antenna or a Multiple Input Multiple Output (MIMO) system. The utilization of MIMO configuration enhances accuracy by incorporating additional metrics, for example angle based such as the Angle of Arrival (AO A) as an additional metric alongside to other metrics for instance mentioned previously. This fold measurement approach contributes to a more sensing awareness and precise localization process.

[0047] 9) Cost-effectiveness and low complexity: The use of OTSM offers simple modulation scheme for backscattering the signal which contributes to costeffectiveness and low complexity design.

[0048] 10) Received Signal Detection: orthogonal time sequency multiplexing (OTSM) is a code-based waveform, allowing the detection of signals even in scenarios with very low received power. This is attributed to its representation in a distinct domain (delay-sequency (DS)), contributing to a high level of detectability.

[0049] The disclosed invention utilizes OTSM as a waveform for joint communication and sensing / localization with backscatter technology. It demonstrates notable technical interest and holds substantial promise for practical applications in the real world. This innovative approach offers a range of advantages, providing tangible benefits across various scenarios.

[0050] One key application lies in Enhanced sensing / Location Awareness Services, where the invention serves as a robust solution for accurate localization, especially in scenarios where traditional technologies encounter challenges. This capability extends to indoor and outdoor positioning systems, smart homes, and beyond. Moreover, the use of OTSM addresses critical issues in loT and Backscatter Networks. It introduces a more reliable and efficient means of localization, with potential applications in smart cities, industrial loT, and other connected environments.

[0051] The power-efficient that offers OTSM to the backscatter devices contributes to Extended Battery Life for loT Devices, enhancing the sustainability and usability of loT deployments that utilize backscatter communication. Another significant advantage is Improved Spectrum Utilization, by eliminating the need to allocate different channels for each backscatter device, the invention optimizes spectrum usage. This not only minimizes interference but also improves overall wireless communication efficiency.

[0052] The flexibility of OTSM in terms of strict synchronization as well as using Walsh Hadamard sequency (orthogonal code) enables it to be adequate in challenging environments, such as in scenarios with strict synchronization requirements or high interference, the extended switching time which decreases power consumption characteristics of the backscatter tags make them more resilient in terms of availability (less duty cycle and extend life cycle). This feature enables the backscatter devices to be used for localization-based services.

[0053] Lastly, the simplicity of the modulation scheme contributes not only to power efficiency but also to Cost-Effective Solutions. This characteristic makes the proposed invention a viable and economical choice for implementing localization services. In summary, the technical innovation introduced by utilizing OTSM in backscatter localization opens avenues for practical applications, offering advantages across a spectrum of real-world scenarios.

[0054] The structural and characteristic features and all advantages of the method subject to the invention will be understood more clearly thanks to the figures given below and the detailed explanation written by referring to these figures, and therefore the evaluation should be made by taking these figures and detailed explanation into consideration.

[0055] Description of the Figures:

[0056] The invention will be described with reference to the accompanying figures, so that the features of the invention will be more clearly understood and appreciated, but the purpose of this is not to limit the invention to these certain regulations. On the contrary, it is intended to cover all alternatives, changes and equivalences that can be included in the area of the invention defined by the accompanying claims. The details shown should be understood that they are shown only for the purpose of describing the preferred embodiments of the present invention and are presented in order to provide the most convenient and easily understandable description of both the shaping of methods and the rules and conceptual features of the invention. In these drawings:

[0057] Figure 1 A view of transmitting an OTSM signal.

[0058] Figure 2 A view of devices receiving the backscattered signal.

[0059] Figure 3 View of BDs reflecting the signal after modulation.

[0060] Figure 4 A view of the receiver's capture the OTSM signals.

[0061] Figure 5 A view that the reflected signal can be neglected over the modulated OTSM signal from another BD.

[0062] Figure 6 A graphical view of the received signal with separability and no interferences in the delay-sequency domain

[0063] Figure 7 A view of the transmitter receiving the OTSM modulated signal from the BDs and performing self-localization.

[0064] Figure 8 A view that delay-sequency resources for localization and communication can be allocated along delays (a) or sequency (b) or only for sensing (c) JSAC.

[0065] Figure 9 A view of OTSM and its robustness to strict synchronization in the case where there is a mismatch in synchronization, the overall signal is same comparing to the case of strict synchronization which demonstrates OTSM flexibility when it comes to strict synchronization.

[0066] The figures to help understand the present invention are numbered as indicated in the attached image and are given below along with their names.

[0067] Disclosure of References:

[0068] 1. Backscatter Device

[0069] 2. Receiver: Access Point / Base Station

[0070] 3. Mobile Transmitter

[0071] 4. Negligible Power

[0072] 5. Sensing

[0073] 6. Communication Detail Description of The Invention:

[0074] The detailed description of the invention delineates crucial components and processes, commencing with the incorporation of Orthogonal Time Sequency Multiplexing (OTSM) as the foundational waveform for backscatter communication (6). Notably, OTSM is envisioned to be integrated into the system either for communication (6) or as a dedicated RF or as optional waveform.

[0075] Using OTSM as waveform enables us to integrate sensing (5) and communication (6) in same resource grid (time frequency) as OTSM uses the same band without interference due to the orthogonality in the delay-sequency domain. As consequence it enables us to have high resolution of the delays (range), doppler (velocity) and angular domain in case of MIMO receiver (2).

[0076] The transmitter and receiver (2) can communicate within the same time-frequency resources but with different delays or sequency and also uses the same physical resources to perform sensing (5) with makes our solution suitable for both sensing (5) and communication (6) in the delay sequency domain with less complexity and high performances. Figure-8 give one example of resources allocation for sensing (5) and for communication (6) along sequency and can be also along delay or both of them.

[0077] The arrangement of backscatter devices (1) is intended to be equidistant or randomly positioned within the environment, with known locations to the receiver (2). Figure- 1, 2, 3, 4, 5, 6 and 7 illustrates one potential configuration with equally spaced backscatter devices (1).

[0078] The backscatter can be used for both communication and sensing for instance if we want to do only sensing one code is sufficient enough to perform localization, for the communication we can attribute more than one code if necessary for example first code represent bit 0 and second code represent bit 0 for a specific backscatter device (1). Figure (8) gives un example of how the resource can be shared in the delay sequency domain. The backscatter devices (1) using OTSM offers flexibility to strict synchronization one example to show that is in figure (9).

[0079] 1) Bi-static Joint Sensing and Communication (JSAC):

[0080] The following steps illustrates the process for joint sensing (5) and communication (6) in bi-static architecture where the sensing (5) / localization is performed at the receiver (2) side:

[0081] • Step 1 :

[0082] The moving Tx initiates communication (6) by emitting an OTSM signal. As depicted in Figure- 1.

[0083] • Step 2:

[0084] The tags receive the signal, which serves as the initial input for their modulation process in time domain. As depicted in Figure-2

[0085] • Step 3 :

[0086] The tags modulate the signal in the time domain using a unique Walsh-Hadamard sequence that represents their fingerprints, assigned by the AP / BS. Subsequently, they backscatter the modulated signal to the receiver (2). As depicted in Figure-3.

[0087] • Step 4:

[0088] The receiver (2) captures the superposition of both the backscattered signals and the direct link signal from the transmitter. As depicted in Figure-4.

[0089] • Step 5:

[0090] The backscattered signal from the tags can be received by another backscatter device (1) (BD). Consequently, the tag will modulate its sequence onto the preexisting modulated signal, resulting in a new modulation characterized by the fingerprint of the current backscatter. However, it is important to note that the power of this backscattered signal is anticipated to be negligible, rendering it undetectable at the receiver (2) side. As depicted in Figure-5.

[0091] • Step 6:

[0092] The Rx receives the superposed signals (broadband signal and backscatters signal) in the delay time and performs 1D / 2D dimensional transform (Walsh-Hadamard transform) to the delay sequency. Subsequently, it extracts the metrics and proceeds with the sensing (5) / localization process. This approach allows the receiver (2) to discern and quantify measurements from each individual tag, providing information for sensing (5) and localization.

[0093] For instance:

[0094] - Localization based on signal metrics such as Received Signal Strength Indicator (RSSI). Averaging each sequency provides powers coming from each signal. Triangulation or trilateration can be used, especially in scenarios with multiple receivers (2), facilitates transmitter localization.

[0095] - In the case of a Multiple-Input Multiple-Output (MIMO) receiver (2), anglebased measurements, such as Angle of Arrival (AoA), can be incorporated alongside other metrics like RSSI.

[0096] The number of backscatter devices (1) depends on the availability of physical resources. The modulation of the OTSM signal by backscatter devices (1) involves a longer switching time, achieved by fixing the backscatter device (1) on a specific impedance over a specific index sequency throughout the entire pulse duration. This design enhances robustness to synchronization compared to Code Division Multiple Access (CDMA) or Orthogonal Frequency Division Multiplexing (OFDM). Moreover, cost-effectiveness.

[0097] The backscattered signal from the BDs is modulated in the time domain.

[0098] The channel:

[0099] The channel is characterized by the following parameters:

[0100] MPC (multipath component) with Delay, doppler, path loss, shadowing.

[0101] The utilization of OTSM makes our system immune to interference from both the direct link and concurrent transmissions due to the orthogonality of the sequency (Walsh-Hadamard). The signals are separable at the receiver (2) side in the delay sequency domain. 2) Mono-static JSAC:

[0102] The process for joint sensing (5) and communication (6) in mono-static architecture where the sensing (5) / localization is performed at the transmitter side for selflocalization:

[0103] The transmitted signal as depicted in Figure- 1 is backscattered to the transmitter as depicted in Figure 2. In this case where the Tx receives the superposed signals in the delay time and performs 1D / 2D dimensional transform (Walsh-Hadamard transform) to the delay sequency. Subsequently, it extracts the metrics and proceeds with the sensing (5) / localization process. This approach allows the moving node to discern and quantify measurements from each individual tag, providing information for sensing (5) and localization.

[0104] For instance:

[0105] - We can also explore the metrics time-based for localization, for example when considering self-localization which is feasible in our case. For instance, techniques like Round-Trip Time (RTT), Round-Trip Offset (RtoF), Time of Flight (ToF), among others, offer opportunities for precise and comprehensive localization within the system. As depicted in Figure-2.

[0106] - In the case of a Multiple-Input Multiple-Output (MIMO) transmitter, angle-based measurements, such as Angle of Arrival (AoA), can be incorporated alongside other metrics like RS SI.

[0107] The foregoing descriptions of specific embodiments of the present technology have been presented for the purposes of illustration and description. They are not intended to be exhaustive or to limit the present technology to the precise forms disclosed, and obviously many modifications and variations are possible considering the above teaching. The embodiments were chosen and described to best explain the principles of the present technology and its practical software, to thereby enable others skilled in the art to best utilize the present technology and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the software or implementation without departing from the spirit or scope of the claims of the present technology.

[0108] In a case that no conflict occurs, the embodiments in the present disclosure and the features in the embodiments may be mutually combined. The foregoing descriptions are merely specific implementations of the present disclosure but are not intended to limit the protection scope of the present disclosure. Any variation or replacement readily figured out by a person skilled in the art within the technical scope disclosed in the present disclosure shall fail within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims

CLAIMS1- The invention relates to method of joint sensing / localization and communication using backscatters via OTSM signaling, its feature is; i. initiating communication (6) mobile transmitter (3) by emitting an OTSM signal, ii. receiving by backscatter devices (1) of a signal which serves as the initial input for their modulation process in the time domain, iii. modulating by the tags the signal in the time domain using a unique Walsh- Hadamard sequence that represents their fingerprints, assigned by the AP / BS, iv. capturing by a receiver (2) the superposition of both the backscattered signals and the direct link signal from the transmitter, v. receiving by the receiver (2) the superposed signals in the delay time and performing 1D / 2D dimensional transform (Walsh-Hadamard transform) to the delay sequency, vi. discerning and quantifying measurements by the receiver (2) from each individual tag, vii. including process steps of providing information by system for sensing (5) and localization.2- The method according to claim 1, characterized by the use of backscatter devices (1) to facilitate transmitter localization at the receiver side and self-localization at the transmitter side.3- The method according to claim 1, characterized by the use of additional techniques in the case of multiple receivers such as triangulation, etc.4- The method according to claim 1, characterized by the use of Orthogonal Time Sequency Multiplexing (OTSM) signal as the fundamental waveform in the system.5- The method according to claim 1 characterized by robustness to strict synchronization.6- The method according to claim 1 characterized by low complexity of the backscatter device (1).7- The method according to claim 1 characterized by high level of detectability of the received signal due to code based waveform (OTSM).8- The method according to claim 1 characterized by low complexity of the backscatter device (1) and low switching rate.9- The method according to claim 1 characterized by exploiting the backscatter devices (1) for localization and for communication along with the broadband communication.10- The method according to claim 1, characterized in that broadband nodes are used that communicate and that the resources reserved for backscatter communication can be utilized for channel estimation of the direct link.11- The method according to claim 1, characterized in that backscatter communication and localization with backscatters are performed, multiple tags can transmits data orthogonally, depending on codes and tag availability we can have the following scenarios i. All sequencies used for communication: In this case, each tag has a unique sequence. On-Off Keying (OOK) modulation is employed, and energy detection is utilized to discern the bits. The detection involves setting a threshold by deriving the noise statistics, ii. Accurate backscatter communication: Tag 1, for instance, can operate with two codes: k' = 1 for bit 1 and k' = 2 for bit 0. Similarly, Tag 2 utilizes codes k' = 3 for bit 1 and k' = 4 for bit 0, and so on. In this scenario, multitaps are present, contributing to the enhancement of our detection capabilities. Detection involves comparing the energy between two sequences to determine the information transmitted by the backscatter device. The detection process is straightforward, no threshold is used here since we only compare the power of each two sequencies to decide the bit,iii. High Data Rates backscatter communication: In this case, when high data rates are required and there are few backscatter devices, multiple codes can be assigned to a single tag. For example, for Tag 1, k' can be assigned as follows: k' = 1 for symbol 00, k' = 2 for symbol 01, k' = 3 for symbol 10, and k' = 4 for symbol 11,

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