Xin Yang

Bio: Xin Yang is an academic researcher from Northwestern Polytechnical University. The author has contributed to research in topics: Computer science & Throughput. The author has an hindex of 4, co-authored 15 publications receiving 77 citations.

Wireless Body Area Networks MAC Protocol For Energy Efficiency and Extending Lifetime

Abstract: Wireless body area networks (WBANs), as an important part of the Internet of things and sensor networks, are becoming more important in health monitoring and entertainment services The sensor nodes in these applications need to transmit information data to personal station and receive control information from personal station to adjust working modes However, unlike an easily rechargeable personal station, body sensor nodes suffer from energy shortages, which affect the nodes lifetimes To solve this problem, we design a novel medium access control (MAC) layer protocol to enhance the energy efficiency and extend the lifetime of body sensor nodes in WBANs The proposed protocol utilizes a hybrid scheme by taking advantage of carrier-sense multiple accesses with the collision avoidance and time division multiple access schemes In addition, we allocate the main transmission overhead at the personal station side and design a novel awaiting order state for sensor nodes to improve energy efficiency Also, the analysis and simulation results demonstrate that the proposed protocol can provide a 6 to 15 decrease in energy consumption from other protocols

Hybrid MAC Protocol Design for Mobile Wireless Sensors Networks

Abstract: With the rapid proliferation of mobile wireless sensors networks (WSNs), which are widely deployed in the Internet of things, the Internet of vehicles, and flying ad hoc networks, more and more researchers are making the effort to improve energy efficiency and throughput of WSNs. In recent years, many protocols have been proposed to solve the energy shortage problem. Some of the protocols are based on cooperative or allocation schemes, some are based on contending schemes, and others are based on the foundation of hybrid schemes. However, it is still difficult to improve the energy efficiency and networks throughput simultaneously. In this article, we present a novel carrier sense multiple accesscollision avoidance and time division multiple access hybrid scheme protocol medium access control (MAC) on the MAC layer to improve the throughput and reduce energy consumption at the same time for mobile WSN with position prediction algorithms in 3-D space. Compared to existing protocols, the proposed protocol can efficiently reduce the energy consumption and significantly improve the throughput, especially for high-speed mobile WSN in the many-to-one communication paradigm. Extensive simulation results prove the performance of the protocol.

Sparsity-Inducing DOA Estimation of Coherent Signals Under the Coexistence of Mutual Coupling and Nonuniform Noise

Abstract: The sparse reconstruction techniques can improve the accuracy and resolution of the direction of arrival (DOA) estimation using sensor arrays. However, due to reflective objects and nonidealities of the antennas and circuitry, the received signals may be coherent and coupled to each other in nonuniform noise environments, causing severe performance degradation of the signal sparse reconstruction. In this paper, a novel sparsity-inducing DOA estimation method is proposed to adapt to such a challenging scenario. To mitigate the nonuniform noise, its power components are first eliminated by a linear transformation. Then, leveraging the steering vector parametrization based on the banded symmetric Toeplitz structure of the mutual coupling matrix (MCM), a reweighted l 1 -norm minimization subject to an error-constrained l 2 -norm is designed to determine the DOA estimates, further enhancing the sparsity and providing robustness against the noise. In addition, a new stochastic Cramer-Rao lower bound (CRLB) of the DOA estimation is derived for the considered adverse condition. The simulation results demonstrate the superiority of the proposed method over its state-of-the-art counterparts.

Medium Access Control for Unmanned Aerial Vehicle Based Mission Critical Wireless Sensor Networks in 3D Monitoring Networks

Abstract: In this paper, a novel medium access control (MAC) layer protocol is introduced for unmanned aerial vehicle (UAV)-based mission critical wireless sensor networks (MC-WSN), which is an important application of mission critical sensor and sensor networks (MC-SSN). The UAVs hovering in the three-dimensional monitoring networks are distributed in subsets according to their distance from the center station. UAVs in the same subset are contending for access and transmission, while each subset is allotted a slot based on adaptive time division multiple access (TDMA) scheme. As a multi-channel system, a novel channel allocation algorithm is presented for subset relay transmission period to optimize the performance of networks. The UAV returning period for charging is utilized in the protocol to enhance the transmission throughput and mitigate delay. Detection slot and position prediction algorithm are designed in the UAV returning period to improve the throughput and reduce the delay. The simulation results verify the improvement on throughput and delays of the proposed protocol for UAV-based MC-WSN.

A Radio Signal Recognition Approach Based on Complex-Valued CNN and Self-Attention Mechanism

Abstract: Automatic modulation recognition (AMR) of radio signals is becoming increasingly important due to its key role in wireless communication system management, monitoring, and control. In this paper, we propose an end-to-end AMR framework based on deep learning (DL), named CCNN-Atten. First, the complex-valued convolutional neural network (CCNN) extracts the features of the radio signal, and the feature calibration (FC) module selectively enhances the important features and suppresses irrelevant features. Then, a temporal context capture (TCC) module uses a modified multi-head attention mechanism (MHA) to capture the temporal dependence in the extracted features. The improved MHA mechanism, as a kind of self-attention mechanism, deploys causal convolutions to encode the temporal information of the input features and captures their local temporal relationship. In addition, due to the limited hardware resources in the real scenarios, we also considered a good compromise between recognition accuracy and computational complexity. Experiments were performed with the RadioML2016.10B, RadioML2016.10A, and RadioML2018.01A datasets, demonstrating the ability of the proposed CCNN-Atten to learn more robust features than other state-of-the-art (SOTA) techniques with 1 ~ 10% higher accuracy and a lower computational complexity than the SOTA models. The experimental results also show that CCNN-Atten achieves outstanding performance in dealing with radio signals with a lower sampling rate and small signal observation window.

The state-of-the-art wireless body area sensor networks: A survey:

Abstract: Wireless body area sensor network is a sub-field of wireless sensor network. Wireless body area sensor network has come into existence after the development of wireless sensor network reached some ...

A Novel Slot-Array Defected Ground Structure for Decoupling Microstrip Antenna Array

Abstract: In this article, a novel slot-array defected ground structure (DGS) for decoupling microstrip antenna array is proposed. The slot-array DGS is etched surrounding each antenna element on the ground plane and parallel to the radiating edges of each antenna element. The decoupling mechanism is elucidated via an equivalent circuit model and the coupled current field analysis, which reveals slot-array DGS has the spatial band-stop characteristic and changes the direction of the partially coupled current, respectively. Both characteristics of the slot-array DGS contribute to mutual coupling reduction. Three practical design examples of applying slot-array DGS to single-linearly polarized (LP), dual-LP, and compact circularly polarized (CP) antenna array are given to illustrate the design process and considerations. The simulated and measured results show that about 50 dB isolation enhancement is obtained by using the slot-array DGS when the edge-to-edge spacing between CP antenna elements is 0.057 wavelength. Additionally, a wheel-shaped absorber based on the electromagnetic loss material is designed and fabricated to reduce the backward radiation caused by slot-array DGS. The absorber has an absorptivity of more than 95% in the frequency range of 1.2–1.35 GHz and suppresses the backward radiation over 12.5 dB in the plane phi = 0° and 16.1 dB in the plane phi = 90° without deteriorating other antenna performances.

Centralized Routing Protocol for Detecting Wormhole Attacks in Wireless Sensor Networks

Abstract: Nodes in wireless sensor networks (WSN) are resource and energy-constrained because they are generally batteries powered and therefore have limited computational capability. Due to the less secure environment in WSN, some malicious nodes at one point can tunnel packets to another location to damage the network in terms of packets dropping and eavesdropping and this is a so-called wormhole attack. Many of the current protocols solve the wormhole attack problem in isolation from the node energy consumption. However, some other proposed solutions consider reducing the energy consumption to detect such attacks but still it is needed to probe better performance. In this paper, we present a lightweight multi-hop routing protocol for 802.15.4 WSN that aims to minimize the energy consumption and also to detect the wormhole attacks. Simulation results prove that our MAC Centralized Routing Protocol (MCRP) outperforms other existing similar protocols.

Cellular Clustering-Based Interference-Aware Data Transmission Protocol for Underwater Acoustic Sensor Networks

Abstract: Recently, the development of three-dimensional interference-aware data transmission methods has attracted the attention of scholars due to the increased interest in exploiting and studying the underwater acoustic sensor networks (UASNs). In this paper, an interference aware data transmission protocol based on cellular clustering architecture is proposed. The protocol involves two steps. The first one is an inter-cell time division multiple access (TDMA) scheduling, which reduces acoustic interference by restricting simultaneous data transmission via adjacent routing paths; and the second one is an intra-cell hierarchical routing, which targets efficient data collection in the submarine and reliable data transmission from the seabed to the surface. Moreover, a novel Ekman spiral-based low-cost location prediction method and a void hole recovery scheme are adopted in each step to support the practicability of proposed protocol. Theoretical analysis and simulations indicate that the proposed protocol has advantages related to the quality of service (QoS) of UASNs because the signal interference is significantly mitigated.

A Hybrid Multi-Class MAC Protocol for IoT-Enabled WBAN Systems

Abstract: This study proposes a hybrid MAC protocol that can efficiently and effectively optimize the communication channel access of a WBAN multi-class system. The proposed protocol consists of two major processes that include the contention phase (CP) and the transmission phase (TP). In the CP, only the biomedical devices that have health packets to transmit randomly contend with equal probabilities using a slotted ALOHA scheme for transmission opportunities and the successful biomedical devices are allocated a transmission time-slot by employing a reservation-based time division multiple access (TDMA) scheme in the transmission phase. A multi-objective optimization problem was formulated to maximize the system sum-throughput, packet success-access-ratio, as well as the reservation ratio, and solved by the controller (i.e., access point) to determine the optimal length of the CP and the number of biomedical devices that can transmit in the TP. Monte Carlo simulation was performed and the optimization solution improved the proposed protocol’s performances. For validation purposes, the simulated results in MATLAB revealed that the proposed protocol performs better than the contemporary system in the context of the system sum-throughput, reservation ratio, and the average health packet delay with performance gains of about 9.2%, 9.5%, and 9.6% respectively.