A METHOD FOR MODULATION BASED ON NON-CYCLIC EQUIVALENT SEQUENCES FOR ASYNCHRONIZED BACKSCATTERING / MEDIUM-IOT COMMUNICATION.

Abstract

The invention relates to the technical field of wireless communication, and specifically to time synchronization in ambient backscattering communication systems. It proposes a modulation method using non-cyclic equivalent sequences to enable asynchronous data transmission in backscattering / ambient IoT communication. This method improves robustness against timing deviations and multipath propagation, making it suitable for low-power, resource-constrained IoT devices operating on ambient backscattering channels. The invention offers a practical and energy-efficient solution for asynchronous backscattering communication where classical synchronization mechanisms are impractical or costly. Figure 1

Description

1 TARIFF FOR SYNCHRONIZED BACKSCATTERING / MEDIUM-IOT COMMUNICATION MODULATION BASED ON NON-CYCLIC EQUIVALENT SEQUENCES METHOD TECHNICAL FIELD The present invention relates to the technical field of wireless communication and asynchronous feedback. Scatter / medium-IoT communication based on non-cyclic equivalent sequences It describes a method for modulation. The invention described is “medium backscattering 10 This falls within the scope of "time synchronization in communication". PREVIOUS TECHNIQUE Ambient backscattering communication uses existing ambient radio frequency (RF) signals to... 15 to low-power or battery-less devices to transmit information by reflecting and modulating. It enables this. In classical systems, the receiving node correctly processes the modulated data. To detect it, it must be synchronized in time with the transmitting or backscattering device. should be. Current solutions generally provide preliminary reference points for time alignment. inserting explicit synchronization mechanisms such as pilot signals or training sequences They rely on efficiency. Although effective, these methods consume additional bandwidth and increase the signal load. increases and may not be suitable for ultra-low power consuming or passive devices in the receiver. Requires additional processing steps. 25 Other approaches involve revealing inconsistent sensing or statistical signal processing techniques. It attempts to reduce or eliminate synchronization. However, these methods introduce noise, It can be sensitive to multipath damping and dynamic channel conditions, which is impractical. This can lead to reduced reliability in applications. 30 With the emergence of 5G and beyond, the world of communications has undergone a significant transformation. The focus has shifted from simply achieving high data rates to large-scale machine-to-machine communication. applications and uses such as (mMTC) and extremely low power communication (ELPC) It has shifted to meet the diverse demands of scenarios (UCs) [1]. Internet of Things 35 2 (IoT) is the long-term, widespread solution necessary for the realization of smart cities and smart homes. By enabling the connection, IoT devices play a very important role in this transition [2]. However, IoT devices Large-scale integration is limited due to the short lifespan of its batteries, which reduces energy consumption. This raises concerns about efficiency and operational costs [3]. To overcome these limitations, an extremely low power consumption and simple RF design was used. Backscatter communication (BC) has emerged as an innovative solution for presenting information [4]. BC provides information It achieves this by reflecting and modulating existing RF signals in order to encode them, thus This method eliminates the need to generate new carrier signals [5]. This method reduces energy usage. By reducing spectral efficiency (SE) while increasing it, 10 energy-efficient and sustainable IoT devices It enables its development [6]. BC is a key feature, especially for 6th generation (6G) Radio Access Networks (RANs). Positioning via expected ambient backscattering communication (AmBC) It also stands out in applications [7]. For communication and location determination, the same 15 By sharing time-frequency (TF) resources, mobile terminals (MTs) can effectively It is traceable. This dual functionality supports target tracking and location-based awareness. Classical localization methods enable the use of LBAS services [8]. It relies on at least three fixed base stations (BSs) for proper positioning [9]. However, The inclusion of backscattering devices (BDs) in a medium along with a single BS was groundbreaking, 20 It offers a low-cost and energy-efficient alternative for location determination. However, BC encounters some challenges when implemented in the real world. Successful modulation For this, aligning the label data with the boundaries of the incoming signal frame is crucial. In practical scenarios, the label is often unaware of these limits, which is why 25 This leads to alignment errors, data collisions, and intersymbol noise (ISI). As a result, the bit error rate (BER) increases. Also, to ensure synchronization in BDs... Additional hardware components are usually required, which makes them cost-effective and low-power. This contradicts the fact that they are designed as devices. Generally, the complexity of existing techniques, energy cost, or bandwidth are the factors. Synchronization that maintains robust performance without bringing about its disadvantages. There will continue to be a need for communication methods that do not require such methods. 3 All the problems and limitations mentioned above are a consequence of the relevant technology. This has made it necessary to create an innovation in the field. A BRIEF DESCRIPTION OF THE INVENTION The present invention aims to eliminate the aforementioned disadvantages and introduce new technologies to the relevant technical field. It is about a method to bring advantages. The invention provides a non-cyclical solution for asynchronous backscattering / medium-to-IoT communication. It relates to a method for modulation based on equivalent sequences. 10 This statement explains how the medium will not require synchronization between the transmitter and the label. It presents a general scheme for generating different modulations for backscattering. This It is obtained by using non-cyclic equivalent sequences. The modulation described actually alleviates the need for strict time synchronization, However, this is the case in all other sequences except for complex exponential functions. There are several equivalent sequences that are not cyclical. This reduces the backscatter communication speed. However, since backscatter communication is slow, this problem can be ignored. The biggest advantage is that it eliminates the need for time synchronization between the transmitter and the label. By eliminating them, it reduces complexity and cost. One aim of the invention is to achieve time synchronization between the transmitter and the medium backscattering. to solve. 25 The described method offers significant advantages for medium backscattering communication: 1. Asynchronous Operation: Time synchronization between the transmitter and the tag. It reduces complexity and cost by eliminating the need for it. 30 2. Versatile Array Design: Complex to adapt to different system requirements. It provides the flexibility to choose sequences such as exponential or Walsh-Hadamard codes. 3. Scalability: Maintaining non-cyclic equivalence while having orthogonal arrays. It supports a scalable number of tags. 35 4 This method increases resilience to timing deviations and multipath propagation, For low-power, resource-constrained IoT devices operating in ambient backscatter channels. It makes it suitable. The invention makes classical synchronization mechanisms impractical or A practical and energy-efficient solution for costly asynchronous backscatter communication. presents. 5 The proposed invention is described in the Third Generation Partnership Project (3GPP) Standards work, Version 18, RP- 223396 relates to "Environmental IoT (Internet of Things)". Environmental IoT (Internet of Things) The relevant study should be addressed in more detail in the future 3GPP agenda. It is expected that, therefore, the subject matter of the invention, due to its importance, will not be limited to Version 18. And it is expected that this will be addressed in subsequent versions as well. The invention's arrangements include active, semi-active, or passive ambient backscattering labels. They are labels. In another arrangement of the invention, the sequences are complex exponential or Walsh-Hadamard 15 These are the codes. In another application of the invention, the transmitter (Tx) is either at least one gNB or a user terminal. (UT) includes at least one wireless transmit / receive unit (WTRU). The proposed invention is for 20 applications in cellular networks (5G, 5G beyond, 6G and beyond), Wi-Fi, IoT, etc. It is applicable in signal technology. The proposed method depends on the method implemented by the computer. The method is a wireless communication located at the base station in the wireless communication system a device (a device is a processor, a memory connected to the processor, and instructions stored in the memory 25 (may include) or a network device or a component of a network device (processor, chip or system of chips). etc.) can be performed by or some network device functions or by the computer by the entire device or its logical modules or software applications applicable. The features and advantages of the regulations can be found in the detailed explanation given below, and This can be understood more clearly from the drawings, where the reference characters correspond to each other. It defines the elements. 35 BRIEF DESCRIPTION OF THE FIGURES In accordance with one or more diverse examples, the current description is as follows: This is explained in detail with references. Drawings are provided for illustrative purposes only. and only illustrates the explanation. These illustrations help the reader understand the explanation further. It is presented to make it easy to understand and to determine the scope, breadth, or meaning of the explanation. This should not be considered a limiting factor in its applicability. Clarity and ease of use are important. It should be noted that these drawings are not necessarily done to scale. Figure 10 1: An example of non-cyclic equivalent orthogonal codes. DETAILED DESCRIPTION OF THE INVENTION This detailed explanation is provided solely to make the subject more understandable. The topic is explained with references to examples without imposing any restrictive effects. 15 All objectives stated above and those that will emerge from the detailed explanation below The aim is to achieve this. The current description allows for medium synchronization without requiring time synchronization between the transmitter and the label. It presents methods for achieving backscatter modulation. 20 This statement explains how the medium will not require synchronization between the transmitter and the label. It presents a general scheme for generating different modulations for backscattering. This It is obtained by using non-cyclic equivalent sequences. The current description describes a cyclical 25 for asynchronous backscattering / medium-to-IoT communication. It offers a method for modulation based on non-equivalent sequences, the method This includes the following: ∑ Generating asynchronous signals via a medium backscattering tag, ∑ The transmission of a signal through a transmitter (Tx), 30 ∑ without performing synchronization, the medium backscatter tag from the air modulating the modulated signal, ∑ provides asynchronous backscattering communication via a transmitter (Tx). Transmission of non-cyclic equivalent sequences ( ). (This transmitter transmits its own signal The medium transmits to a specific receiver, independent of IoT. 35 6 ∑ Ambient IoT takes this existing signal and embeds some information into it in real time. It uses modulation to communicate with another receiver (reader). ∑ Ambient IoT is an interference system that uses the existing RF signal to transmit its own data. (like) In this approach, a transmitter (Tx) modulates the medium from the air via a backscattering tag. It sends a signal. The tag modulates the antenna impedance, thereby changing the reflection coefficient and the existing RF. It writes data to the carrier. 10 Examples of a transmitter (Tx) include wireless devices such as a gNB or a user terminal (UT). Transmission / reception units (WTRUs) are present. Media backscattering tags are active, semi-active or It could be a passive label. To enable asynchronous backscattering communication, Tx is cyclical. It passes non-equivalent sequences ( ). This condition can be expressed as follows: Here, is the sequence length, and modulo represents . Frequency representation of time series . and . respectively. When this happens, in order for these to be non-cyclic equivalents, the following should be included: They must comply with the restrictions. Here, it represents multiplication on an element-by-element basis. The core concept behind synchronizing free signal generation is cyclical. The goal is to select non-equivalent orthogonal sequences. Walsh-Hadamard codes include those containing 1 and -1. It is one example, but it can be generalized to all arrays. Examples of these sequences include complex exponents: 30 Examples of these sequences that use Walsh-Hadamard sequences include every N orthogonal For Walsh code (1,-1), non-cyclic equivalent codes 7 The sequences for are shown in Figure 1. These are the non-cyclic equivalents. It should be noted that each code represents only one combination. Example: Walsh codes are mutually orthogonal to all other rows / columns. Thus, the 4 sequences are as follows: 5 Implementation of 4x4Walsh–Hadamard Codes The cyclic equivalence between c1, c2, c3, and c4 is checked: ∑ c_1 = [1,1,1,1] 15 ∑ Any cyclic shift is still [1,1,1,1]. ∑ → Only 1 unique sequence. ∑ c2=[1,−1,1,−1] ∑ Shifts: [−1,1,−1,1][-1,1,-1,1] etc. ∑ → Only 2 unique sequences (repeats after 2 shifts). 20 ∑ c3=[1,1,−1,−1] Shifts: [1,−1,−1,1][1,-1,-1,1], [−1,1,1,−1]. → 4 unique cyclical versions. ∑ c4=[1,−1,−1,1] Shifts: [−1,−1,1,1], [−1,1,1,−1], [1,1,−1,−1]. 25 → It should be noted that these are precisely the shifts of c3. Like this: ∑ c3 and c4 are cyclically equivalent. ∑ c1 is unique on its own. ∑ c2 is unique on its own. 30 For asynchronous medium backscatter communication, only c1, c2 and c3 or c1, It is necessary to use c2 and c4. 8 REFERENCES [1] MSJ Solaija, SE Zegrar, and H. Arslan, “Orthogonal Frequency Division Multiplexing: The Way Forward for 6G Physical Layer Design?” IEEE Vehicular Technology Magazine, 2024. 5 [2] T. Jiang, Y. Zhang, W. Ma, M. Peng, Y. Peng, M. Feng, and G. Liu, “Backscatter Communication Meets Practical Battery-Free Internet of Things: A Survey and Outlook,” IEEE Communications Surveys & Tutorials, 2023. [3] T. Kim Geok, K. Zar Aung, M. Sandar Aung, M. Thu Soe, A. Abdaziz, C. Pao Liew, F. Hossain, C. P. Tso, and W. H. Yong, “Review of Indoor Positioning: Radio Wave 10 Technology,” Applied Sciences, vol. 11, no. 1, p. 279, 2020. [4] C. Song, Y. Ding, A. Eid, J. G. Hester, X. He, R. Bahr, A. Georgiadis, G. Goussetis, and M. M. Tentzeris, “Advances in Wirelessly Powered Backscatter Communications: From Antenna / RF Circuitry Design to Printed Flexible Electronics,” Proceedings of the IEEE, vol. 110, no. 1, pp. 171–192, 2021. 15 [5] C. Boyer and S. Roy, “Invited Paper—Backscatter Communication and RFID: Coding, Energy, and MIMO Analysis,” IEEE Transactions on Communications, vol. 62, no. 3, pp. 770–785, 2013. [6] R. Giuliano, “From 5G-Advanced to 6G in 2030: New Services, 3GPP Advances and Enabling Technologies,” IEEE Access, 2024. 20 [7] F. Liu, Y. Cui, C. Masouros, J. Xu, T. X. Han, Y. C. Eldar, and S. Buzzi, “Integrated Sensing and Communications: Toward Dual- Functional Wireless Networks for 6G and Beyond,” IEEE Journal on Selected Areas in Communications, vol. 40, no. 6, pp. 1728– 1767, 2022. [8] M. Z. Win, F. Meyer, Z. Liu, W. Dai, S. Bartoletti, and A. Conti, “Efficient Multisensor 25 Localization for the Internet of Things: Exploring a New Class of Scalable Localization Algorithms,” IEEE Signal Processing Magazine, vol. 35, no. 5, pp. 153–167, 2018. [9] S. M. Maghdid et al., “A Comprehensive Review of Indoor / Outdoor Localization Solutions in IoT Era: Research Challenges and Future Perspectives,” 2021.

Claims

9 REQUESTS 1. Asynchronous backscattering / non-cyclic for medium-to-IoT communication. a computer-implemented modulation based on equivalent sequences It is a method, and its characteristic feature is that the method includes the following steps: 5 ∑ asynchronous signals via an environment backscattering label creation, ∑ The transmission of a signal through a transmitter (Tx), ∑ without performing synchronization, by the medium backscatter tag Modulation of the signal modulated from the air, 10 ∑ A transmitter (Tx) to provide asynchronous backscattering communication. Transmission of equivalent non-cyclic sequences via this method.

2. Method according to claim 1, where the transmitter (Tx) has at least one gNB or a user 15 terminals (UTs) must contain at least one wireless transmission / reception unit (WTRU) between them. It is characterized by...

3. The method according to claim 1, characterized by the use of active and semi-active backscattering labels in the environment. or is characterized by being a passive label.

4. The method according to claim 1, whose characteristic is that sequences, complex exponents or Walsh- It is characterized by the presence of Hadamard codes.