Wireless Transmission Scheme Research Articles

Real-time monitoring of aero-engine vibration signals by wireless communication technology

Abstract The conventional way to monitor the vibration signals of aircraft engines is to use wired communication sensors to transmit and collect the signals on a fixed platform on the ground. The signal acquisition equipment of wired communication technology has various drawbacks, resulting in the inability to collect vibration signals when the object under test is in real operating conditions. Based on previous studies, this research team uses a 2.4G wireless transmission scheme to realize short-distance wireless transmission of aero-engine vibration signals, and a 4G cellular communication scheme to realize long-distance wireless transmission of aero-engine vibration signals. The acquired signals are displayed and monitored using the tool developed in LabVIEW2022. The designed tool is successfully applied in the engineering practice of engine maintenance, realizing the remote real-time monitoring of the engine operation status, shortening the monitoring cycle of the equipment from hourly to real-time level, and greatly facilitating the technical support work of engineers and technicians.

Rotation-Tolerant Wireless Power Transmission Scheme with Smart Positioning for Cognitive Research on Moving Animals.

This article presents a novel wireless power transmission scheme designed for moving loads. Specifically focused on compensating for the tilt misalignment of the receiver. By utilizing phase-shifted excitation signals from an array of transmitters, the proposed scheme effectively mitigates the impact of misalignment, locally. The application of this scheme holds particular relevance for studying the behavior of moving animals in cognitive research. The system incorporates a cage with two transmitter arrays positioned on the top and bottom sides. To smart determining the receiver's position, the proposed structure utilizes current feedback from the driving circuits and employs SVM (Support Vector Machine) classification algorithms for positioning. Furthermore, when the receiver coil is tilted, a phase shift mechanism significantly enhances the power delivered to the receiver. Additionally, the use of an overlapped transmitter array enhances rotation tolerance and improves the uniformity of the magnetic fields for moving objects. The performance of the proposed scheme is validated through extensive simulations and measurements using a fabricated prototype. Notably, the designed system achieves a power delivery of 296 mW to the load at a 90° angular misalignment, compared to 1.67 µW delivered by conventional array system.

Communication mode selection and game theoretic bandwidth sharing model for D2D relay communication

Device-to-device (D2D) communication plays a crucial role in achieving successful implementation of 5G+ and 6G wireless networks. The selection of the communication mode is a vital parameter that enables the activation of a communication link through D2D relays. Consequently, this selection can be considered the fundamental functionality responsible for activating the communication mode of transmission within any device-to-device communication network. This research paper proposes a communication mode selection scheme based on a hexagonal cellular structure. The scheme holds significant potential for application in various wireless transmission schemes. Additionally, the paper investigates the issue of bandwidth sharing in device-to-device networks. In future wireless systems, device-centric approaches will be widely adopted, necessitating a key focus on spectrum sharing. The proposed scheme not only facilitates wireless users in sharing their available spectrum with others but also allows them to receive financial rewards in return. This cooperative sharing approach fosters collaboration among wireless users. Furthermore, the paper compares the performance of two utility functions for the purpose of bandwidth sharing. The Cobb-Douglas model is utilized to present the proposed bandwidth-sharing scheme between two users. Simulation experiments are conducted to determine the percentage of bandwidth shared by the two users under various scenarios, including a case where both users share 50% of the bandwidth. The results indicate that the optimal utility function is achieved when one user shares 10% of the bandwidth while the other user shares 90%.

High-Quality Secure Wireless Transmission Scheme Using Polar Codes and Radio-Wave Encrypted Modulation

High-Quality Secure Wireless Transmission Scheme Using Polar Codes and Radio-Wave Encrypted Modulation

SCIM: Incorporating secure communication and interference management in one operation

Due to the broadcast nature of wireless communications, users’ data transmitted wirelessly is susceptible to security/privacy threats. Meanwhile, as a result of the limitation of spectrum resources, massive wireless connections will incur serious interference, which may damage the efficiency of data transmission. Therefore, improving both efficiency and secrecy of data transmission is of research significance. In this paper, we propose a wireless transmission scheme by taking both Secure Communication (SC) and Interference Management (IM) into account, namely SCIM. With this scheme, an SCIM signal is generated by the legitimate transmitter (Tx) and sent along with the desired signal, so that the SCIM signal can interact with and suppress the environmental interference at the legitimate receiver (Rx). Meanwhile, the SCIM signal may interfere with the eavesdropper in the coverage of legitimate transmission so as to deteriorate the eavesdropping performance. Therefore, the secrecy of desired transmission is improved. In this way, both the transmission efficiency and privacy are enhanced. Then, by taking various transmission preferences into account, we develop different implementations of SCIM, including Interference Suppression First SCIM (ISF-SCIM), Data Transmission First SCIM (DTF-SCIM), Anti-Eavesdropping First SCIM (AEF-SCIM), and Secrecy Rate Maximization SCIM (SRM-SCIM). Our in-depth simulation results have shown the proposed methods to effectively improve the efficiency and secrecy of the legitimate transmission.

Privacy amplification for wireless federated learning with Rényi differential privacy and subsampling

<abstract><p>A key issue in current federated learning research is how to improve the performance of federated learning algorithms by reducing communication overhead and computing costs while ensuring data privacy. This paper proposed an efficient wireless transmission scheme termed the subsampling privacy-enabled RDP wireless transmission system (SS-RDP-WTS), which can reduce the communication and computing overhead in the process of learning but also enhance the privacy protection ability of federated learning. We proved our scheme's convergence and analyzed its privacy guarantee, as well as demoonstrated the performance of our scheme on the Modified National Institute of Standards and Technology database (MNIST) and Canadian Institute for Advanced Research, 10 classes datasets (CIFAR10).</p></abstract>

A hybrid optical-wireless network for decimetre-level terrestrial positioning.

Global navigation satellite systems (GNSS) are widely used for navigation and time distribution1-3, features that are indispensable for critical infrastructure such as mobile communication networks, as well as emerging technologies such as automated driving and sustainable energy grids3,4. Although GNSS can provide centimetre-level precision, GNSS receivers are prone to many-metre errors owing to multipath propagation and an obstructed view of the sky, which occur particularly in urban areas where accurate positioning is most needed1,5,6. Moreover, the vulnerabilities of GNSS, combined with the lack of a back-up system, pose a severe risk to GNSS-dependent technologies7. Here we demonstrate a terrestrial positioning system that is independent of GNSS and offers superior performance through a constellation of radio transmitters, connected and time-synchronized at the subnanosecond level through a fibre-optic Ethernet network8. Using optical and wireless transmission schemes similar to those encountered in mobile communication networks, and exploiting spectrally efficient virtual wideband signals, the detrimental effects of multipath propagation are mitigated9, thus enabling robust decimetre-level positioning and subnanosecond timing in a multipath-prone outdoor environment. This work provides a glimpse of a future in which telecommunication networks provide not only connectivity but also GNSS-independent timing and positioning services with unprecedented accuracy and reliability.

Channel-Adaptive Wireless Image Transmission With OFDM

We present a learning-based channel-adaptive joint source and channel coding (CA-JSCC) scheme for wireless image transmission over multipath fading channels. The proposed method is an end-to-end autoencoder architecture with a dual-attention mechanism employing orthogonal frequency division multiplexing (OFDM) transmission. Unlike the previous works, our approach is adaptive to channel-gain and noise-power variations by exploiting the estimated channel state information (CSI). Specifically, with the proposed dual-attention mechanism, our model can learn to map the features and allocate transmission-power resources judiciously based on the estimated CSI. Extensive numerical experiments verify that CA-JSCC achieves state-of-the-art performance among existing JSCC schemes. In addition, CA-JSCC is robust to varying channel conditions and can better exploit the limited channel resources by transmitting critical features over better subchannels.

Multi-RIS aided 3D secure precise wireless transmission

In this paper, multiple reconfigurable intelligent surfaces (RIS) aided secure precise wireless transmission (SPWT) schemes are proposed in the three-dimensional (3D) wireless communication scenario. Unavailable direct path channels from transmitter to receivers are considered when the direct paths are obstructed by obstacles. Then, multiple RISs are utilized to achieve SPWT through the reflection path among transmitter, RISs and receivers in order to enhance the communication performance and energy efficiency simultaneously. First, a maximum-signal-to-interference-and-noise ratio (MSINR) scheme is proposed in a single user scenario. Then, the multi-user scenario is considered where the illegitimate users are regarded as eavesdroppers. A maximum-secrecy-rate (MSR) scheme and a maximum-signal-to-leakage-and-noise ratio (MSLNR) are proposed. The former achieves a better secrecy rate (SR) performance but incurs a higher complexity. The latter has a lower complexity than the MSR scheme with an SR performance loss. Simulation results show that both singleuser scheme and multi-user scheme can achieve SPWT which transmits confidential message precisely to location of desired users. Moreover, MSLNR scheme has a lower complexity than the MSR scheme, while the SR performance is close to that of the MSR scheme.

Aerial Refueling: Scheduling Wireless Energy Charging for UAV Enabled Data Collection

The working scope and working time of small size unmanned aerial vehicles (UAVs) are limited because of the limited battery capacity. In this work, inspired by aerial refueling for aircrafts, we propose a wireless power transmission (WPT) scheme by categorizing the UAVs into charging UAV (CUAV) and mission UAV (MUAV) for charging UAVs without interrupting the mission. In the proposed aerial refueling scheme, mission UAVs (MUAV) can be recharged by charging UAVs on the fly and operate in a perpetual manner. The feasibility of aerially wireless charging for small UAVs is firstly discussed and evaluated. Then we consider a practical application scenario of multiple MUAVs for collecting data from several points of interest, where the MUAVs are recharged by CUAVs. Accordingly, the issue of scheduling the flying path and charging process of each CUAV to minimize the mission time arises. Deep reinforcement learning (DRL) based algorithms for scheduling both single and multiple CUAVs are proposed and deployed. Extensive simulation evaluations demonstrate that, by applying the proposed aerial refueling scheme, CUAVs can explore and optimize the scheduling strategies, thereby improving the system performance in terms of mission completion and charging efficiency.

RIS-Assisted UAV Communications for IoT With Wireless Power Transfer Using Deep Reinforcement Learning

Many of the devices used in Internet-of-Things (IoT) applications are energy-limited, and thus supplying energy while maintaining seamless connectivity for IoT devices is of considerable importance. In this context, we propose a simultaneous wireless power transfer and information transmission scheme for IoT devices with support from the reconfigurable intelligent surface (RIS)-aided unmanned aerial vehicle (UAV) communications. In particular, in the first phase, IoT devices harvest energy from the UAV through wireless power transfer; and then in the second phase, the UAV collects data from the IoT devices through information transmission. To characterise the agility of the UAV, we consider two scenarios: a hovering UAV and a mobile UAV. Aiming at maximising the total network sum-rate, we jointly optimise the trajectory and the power allocation of the UAV, the energy harvesting scheduling of IoT devices, and the phase-shift matrix of the RIS. We formulate a Markov decision process and propose two deep reinforcement learning algorithms to solve the optimisation problem of maximising the total network sum-rate. Numerical results illustrate the effectiveness of the UAV’s flying path optimisation and the network’s throughput of our proposed techniques compared with other benchmark schemes. Given the strict requirements of the RIS and UAV, the significant improvement in processing time and throughput performance demonstrates that our proposed scheme is well applicable for practical IoT applications.

A Learning-Aided Intermittent Cooperative Jamming Scheme for Nonslotted Wireless Transmission in an IoT System

The boom of the Internet of Things (IoT) has exposed many security issues in recent years. Cooperative jamming, including the continuous jamming strategy (CJS) and intermittent jamming strategy (IJS), is an effective approach toward secure wireless communication in the physical layer. CJS used to be a primary physical-layer security technology that sends cooperative jamming signals at the expense of energy consumption. Different from CJS, IJS is more energy efficient. The feasibility of IJS has been proved in a slotted scenario, which motivates us to design IJS in a nonslotted scenario. In this article, we discuss the feasibility of IJS for a nonslotted transmission IoT system and formulate an optimization problem based on a sense-harvest-jam policy. This problem is to find the optimal matching precision between durations of artificial noise and legitimate signals. To solve this problem, we exploit a backpropagation-neural-network model to analyze jamming duration proportion and derive the optimal proportion for the binary phase-shift keying modulation. Finally, we design a matching precision optimization algorithm to achieve the optimal nonslotted secure transmission. Simulation results on jamming efficiency demonstrate that the proposed IJS has preferable secure performance than the CJS under energy constraints.

Implementation of an encrypted-compressed image wireless transmission scheme based on chaotic fractional-order systems

In this paper, an encryption, compression and transmission scheme is proposed. The scheme is based on fractional-order chaotic systems combined with Discrete Wavelet Transform (DWT) and Quadrature Phase Shift Keying (QPSK) modulation. The cipher performs rounds of digital operations between the vector states of the fractional-order system and the image to be encrypted. The implementation of the transmission process is made between a pair of software defined radio modules through a QPSK modulation scheme. The experimental results and security analysis show adequate performances for several applications in the presence of multiple attacks and environmental noise.

Backscatter Aided Wireless Communications on High-Speed Rails: Capacity Analysis and Transceiver Design

Fast time-varying channel parameters and large penetration losses for signals passing through train carriages are two well-known challenges for wireless communications on high speed rails (HSRs). In this paper, we introduce, for the first time, backscatter technology into HSR wireless communications, which can address these two challenges and yet have low complexity of signal processing and low cost of circuit implementation compared with traditional solutions such as relaying or beamforming. Specifically, we propose a backscatter aided wireless transmission (BAWT) scheme and demonstrate that it outperforms the existing direct wireless transmission (DWT) scheme. We derive the upper and lower bounds of channel capacity for BAWT and prove that it exceeds that of DWT on certain conditions. We also propose the transceiver design for both BAWT and DWT, including joint carrier frequency offset and channel estimator, and signal detector. We show that BAWT, rather than DWT, can obtain the channel statistical information in practical applications due to fixed train antennas and unchanged tracks, which can be utilized to facilitate channel estimation. Finally, simulation results are provided to corroborate the proposed solutions.

Feeder Communication for Integrated Networks

The integrated communication system has received increasing attention to establish a fully connected world in the eras of beyond fifth generation wireless communication and sixth generation wireless communication systems, where a wide range of services with distinct requirements needs to be accommodated, covering distinct scenarios such as terrestrial, ocean, outer space, and underwater. In this article, we first propose the idea of feeder communication, which aims to provide truly seamless and ubiquitous on-demand coverage for any human activity. Compared to the traditional integrated networks, feeder communication focuses on reliable data transmission over multiple propagation media such as outer space, stratosphere, troposphere, and underwater. Due to the significant differences of radio propagation characteristics in different media, feeder communication requires a large number of feeder nodes for inter-medium transmissions, a well-designed network structure, and intelligent wireless transmission and control schemes. The basic concepts, features, application scenarios, network architecture, and the corresponding wireless transmission technologies of feeder communication are presented in detail, and challenges and future directions are also pointed out in this article.

Regional robust secure precise wireless transmission design for multi-user UAV broadcasting system

In this paper, two regional robust secure precise wireless transmission (SPWT) schemes for multi-user unmanned aerial vehicle (UAV), (1)regional signal-to-leakage-and-noise ratio (SLNR) and artificial-noise-to-leakage-and-noise ratio (ANLNR) (R-SLNR-ANLNR) maximization and (2) point SLNR and ANLNR (P-SLNR-ANLNR) maximization, are proposed to tackle with the estimation errors of the target users’ location. In the SPWT system, the estimation error for SPWT cannot be ignored. However, the conventional robust methods in secure wireless communications optimize the beamforming vector in the desired positions only in statistical means and cannot guarantee the security for each symbol. The proposed regional robust schemes are designed for optimizing the secrecy performance in the whole error region around the estimated location. Specifically, with the known maximal estimation error, we define the target region and wiretap region. Then, we design an optimal beamforming vector and an artificial noise projection matrix, which achieve the confidential signal in the target area having the maximal power while only few signal power is conserved in the potential wiretap region. Instead of considering the statistical distributions of the estimated errors into optimization, we optimize the SLNR and ANLNR of the whole target area, which significantly decreases the complexity. Moreover, the proposed schemes can ensure that the desired users are located in the optimized region, which are more practical than the conventional methods. Simulation results show that our proposed regional robust SPWT design is capable of substantially improving the secrecy rate compared to the conventional non-robust method. The P-SLNR-ANLNR maximization-based method has the comparable secrecy performance with lower complexity than that of the R-SLNR-ANLNR maximization-based method.

풍력 터빈 날개에 장착된 에너지 하베스터를 이용한 센싱 데이터의 무선전송 기법

풍력 터빈 날개에 장착된 에너지 하베스터를 이용한 센싱 데이터의 무선전송 기법

Spectral encapsulation of OFDM systems based on orthogonalization for short packet transmission

A spectrally encapsulated (SE) orthogonal frequency-division multiplexing (OFDM) precoding scheme for wireless short packet transmission, which can suppress the out-of-band emission (OoBE) while maintaining the advantage of the cyclic prefix (CP)-OFDM, is proposed. The SE-OFDM symbol consists of a prefix, an inverse fast Fourier transform (IFFT) symbol, and a suffix generated by the head, center, and tail matrices, respectively. The prefix and suffix play the roles of a guard interval and suppress the OoBE, and the IFFT symbol has the same size as the discrete Fourier transform symbol in the CP-OFDM symbol and serves as an information field. Specifically, as the center matrix generating the IFFT symbol is orthogonal, data and pilot symbols can be allocated to any subcarrier without distinction. Even if the proposed precoder is required to generate OFDM symbols with spectral efficiency in the transmitter, a corresponding decoder is not required in the receiver. The proposed scheme is compared with CP-OFDM in terms of spectrum, OoBE, and bit-error rate.

Monitoring and analysis of athletes’ local body movement status based on BP neural network

At present, the body recognition detection of athletes is mostly technical recognition, and the detection of exercise state is less, and the related research is basically blank. Based on this, based on BP neural network algorithm, this study develops athletes’ motion capture based on wearable inertial sensors, and builds a wireless signal transmission scheme based on sensor system. At the same time, this paper constructs the coordinate system to complete the attitude angle settlement and motion recognition and combines the athlete’s actual situation to establish the athlete’s limb trajectory calculation model and analyzes the athletes’ movement patterns. In addition, this paper combines neural network algorithm to analyze, and builds a neural network based athlete body motion recognition model, and analyzes the model effectiveness through simulation system. Studies have shown that when using time domain features+trajectory features as neural network inputs, the hand recognition rate is somewhat improved compared to the use of only time domain features as neural network inputs. It can be seen that the algorithm model of this study has certain validity and can be used as a reference for subsequent related research gradient theory.

Temporal information based GoP adaptation for linear video delivery schemes

An original wireless video transmission scheme called SoftCast has been recently proposed to deal with the issues encountered in conventional wireless video broadcasting systems (e.g. cliff effect). In this paper, we evaluate and optimize the performance of the SoftCast scheme according to the transmitted video content. Precisely, an adaptive coding mechanism based on GoP-size adaptation, which takes into account the temporal information fluctuations of the video, is proposed. This extension denoted Adaptive GoP-size mechanism based on Content and Cut detection for SoftCast (AGCC-SoftCast) significantly improves the performance of the SoftCast scheme. It consists in modifying the GoP-size according to the shot changes and the spatio-temporal characteristics of the transmitted video. When hardware capacities, such as buffer or processor performance are limited, an alternative method based only on the shot changes detection (AGCut-SoftCast) is also proposed. Improvements up to 16 dB for the PSNR and up to 0.55 for the SSIM are observed with the proposed solutions at the cut boundaries. In addition, temporal visual quality fluctuations are reduced under 1dB in average, showing the effectiveness of the proposed methods.