Short-range Wireless Communication Research Articles

Water Spiral Dielectric Resonator Antenna for Generating Multimode OAM

This letter presents a novel water spiral dielectric resonator antenna (DRA) to generate multimode orbital angular momentum (OAM) waves. The shell of the spiral DRA filled with distilled water is designed as a cylinder with a spiral paraboloid on one side produced by a 3-D printer, and fed with two orthogonal signals at the other (bottom) side to excite higher order modes. By changing the radius, height, and notch height of the spiral DRA, l = ±1 OAM modes can be generated at 4.8 and 5.6 GHz, and l = ±3 OAM modes can be generated at 5.11, 5.66, and 6.36 GHz, respectively. The measurement results show that the 10 dB frequency bandwidth of the spiral DRA from 5.07 to 5.14 GHz and isolation excess of 20 dB can be achieved. The proposed spiral DRA with low cost, compact construction, and easy processing has the potential in a short-range OAM wireless communication.

A Compact UWB Bandpass Chip Filter on a GaAs Substrate with Modified Chebyshev Structure

Ultra-Wideband (UWB) systems are widely used in low-power, high-speed, high-security short-range wireless communication systems throughout digital homes and offices. In the RF front-end of a UWB system, bandpass filters (BPFs) are used to put through the passband signals and reject the stopband signals. Most UWB BPFs are designed with dielectric materials on circuit boards or LTCC technology. In this paper, a very compact fully integrated UWB chip filter is proposed and designed on a GaAs substrate with nitride as dielectric layers to meet the small size requirement of portable devices for next-generation UWB applications. The filter is constructed with a modified Chebyshev structure. The final filter circuit contains only four inductors instead of six for the conventional Chebyshev filter, which makes the chip more compact and cost effective. The filter is designed and fabricated on a 0.25 μm GaAs pHEMT technology with a chip size of only 0.73 mm × 0.51 mm including the chip edge and scribe line area, while the filter core area is only 0.61 mm × 0.39 mm, including bonding PADs. The measurement results illustrated that the proposed BPF shows a passband covering the frequency range of 3.1–9.0 GHz, the minimum passband insertion loss is only 1.5 dB, the stopband rejection is better than −30 dB throughout frequencies below 2 GHz and above 12 GHz, S11 is less than −16 dB, and S22 is better than −11 dB during the whole passband range. It demonstrated that the proposed filter can be considered as one of the most compact UWB filters.

Design of a Superposition Coding PPM-DCSK System for Downlink Multi-User Transmission

The conventional orthogonal multiple-access-based downlink transmission for the differential chaos shift keying system with pulse-position modulation (PPM-DCSK) suffers from lower energy efficiency and data rate. To tackle this problem, a low-complexity superposition coding PPM-DCSK (SC-PPM-DCSK) system for downlink multi-user chaotic communication is proposed in this paper. The proposed system exploits the superposition coding principle on the reference signal and the information-bearing signal to achieve multi-user simultaneous information transmission for the downlink scenario, thus significantly improving the energy efficiency and transmission rate. Furthermore, the analytical expression for the error performance and the throughput of the proposed system are precisely derived over additive white Gaussian noise and multipath Rayleigh fading channels. Simulation results not only verify the accuracy of the analytical method but also illustrate the proposed transmission scheme in achieving significant performance gain compared with the time-sharing-based PPM-DCSK and multiresolution DCSK systems. Due to such superiority, the proposed SC-PPM-DCSK system can be deemed to be an outstanding scheme for downlink multi-user short-range wireless communications.

Design and Implementation of 802.15.4 Transceiver for Wireless Personal Area Networks (WPANs) on FPGA

The IEEE 802.15.4 standard provides mainly accessing, monitoring, and controlling capability of the Wireless devices. This standard supports short-range wireless communications and Low Rate (LR) - Wireless Personal Area Networks (WPANs). This manuscript presents the fully integrated digital 802.15.4 Transceiver, which suitable to ZigBee Device Standard at 2.4GHz range. The 802.15.4 Transceiver design includes an 8-bit input data sequence mapped to lower and Upper Symbols followed by Chip-sequence conversion as per the IEEE standard. The chip sequences are mapped separately as even and odd sequences used for the Offset-QPSK Modulation. The chip synchronization achieved by using a proper clocking mechanism on the receiver side. The 802.15.4 Transceiver design is implemented on Artix-7 FPGA using Xilinx Environment. The hardware constraints like Area (Slices), Frequency, and Power are analyzed. The proposed work also compared with existing similar approaches with more significant improvements in chip area and Power.

Optimal Real-time Static and Dynamic Air Quality Monitoring System

Objective: The objective of this study is to design and implement an effective low-cost air quality monitoring system that has the ability to monitor real-time air quality over a wide geographical area. Methodology: The proposed system is developed for CO and NO2. As a test case, our developed system is deployed in Quetta city, both in static and dynamic situations and the concentration level of CO and NO2 in the air are measured and stored, along with their time, date, and location. In order to analyze this information, the stored data are then transferred to a data collection center via short-range wireless communication. Findings: Many air quality monitoring systems exits in the market; however, most of these systems have several design limitations such as size, cost, inability to move, and demand for continuous internet connectivity. Therefore, in this study, we have designed and implemented an effective low-cost air quality monitoring system that has the ability to monitor real-time air quality over a wide geographical area. Moreover, unlike existing air quality monitoring systems, the proposed system does not require any continuous internet connection and it can monitor the concentration level of pollutants in the air both in a static position and in mobile situations. The test results show that our proposed system can perform very well in both static and mobile situations. Applications: The proposed monitoring mechanism can help environmental experts and the general public to develop a more robust strategy against the adverse effects of air pollution. Keywords: Sensors, Pollution, Air-Quality, Global Positioning System (GPS), Zigbee.

IoT methodologies: comparative study

Abstract The Internet of Things or the Internet of Everything is a new and a potentially disruptive technology paradigm. It describes several technologies such as RFID, short range wireless communications, and research disciplines that can connect physical objects from the real world to the internet. To implement IoT solutions, they exist software development approaches like Scrum and Kanban, also, others are adapted viz; Large-Scale Scrum, Scaled Agile Framework and so on., and many methods have proposed such as Ignite | IoT Methodology and IoT Methodology. Most of them have taken agile thinking as a strategy. However, they are monolithic, which are not easy to adopt. Then, a new method is needed to handle the real nature of IoT, particularity, to handle distributed, mobile and human out-of-the-loop concerns, and that can grow as new product evolve and new problems emerge. This research studies and analyses some of the existing IOT methodologies. Particularly, it focuses on these methodologies Scrum, Kanban, Scaled Agile Framework, Ignite | IoT Methodology and IoT Methodology. Our study evaluates their capabilities and compares their main characteristics and behaviors in terms of various methodologies of IoT. The comparison presented in this paper would benefit in selecting an appropriate methodology for the IoT projects. In addition, it identifies their advantages and limits in order to suggest a new approved IoT methodology.

Analysis and Performance Evaluation of Bluetooth Low Energy Piconet Network

This paper presents the performance analysis of Bluetooth Low Energy (BLE) IEEE 802.15.1 standard in the piconet topology networks. The performance of the BLE network is analyzed in terms of connection interval (CI) and the number of slaves (NS) by using OMNET++ (v4.6) simulator. In the performance investigation process Data Length Extension (DLE) features is used with an application payload size of 60 bytes in order to achieve the best performance in a BLE (P2P) network. The modeled networks and due to the nature of short-range BLE wireless communication show a good matching between analytical and simulation results. For Single-Slave (or one like) piconet the obtained maximum simulation throughput is 478.7 kbps when a connection interval of (7.5) ms is used.

Attacks and Defenses in Short-Range Wireless Technologies for IoT

The Internet of Things, abbreviated as IoT, is a new networking paradigm composed of wireless and wired networks, geographically distributed and interconnected by a “secured” backbone, essentially, the Internet. It connects billions of heterogeneous devices, called Things, using different communication technologies and provides end-users, all over the world, with a variety of smart applications. IoT constitutes a new evolution for the Internet in terms of diversity, size, and applications. It also invites cybercriminals who exploit IoT infrastructures to conduct large scale, distributed, and devastating cyberattacks that may have serious consequences. The security of IoT infrastructures strongly depends on the security of its wired and wireless infrastructures. Still, the wireless infrastructures are thought to be the most outspread, important, and vulnerable part of IoT. To achieve the security goals in the wireless infrastructures of IoT, it is crucial to have a comprehensive understanding of IoT attacks, their classification, and security solutions in such infrastructures. In this paper, we provide a survey of attacks related to the wireless infrastructures of IoT in general, and to the most used short-range wireless communication technologies in the resource-constrained part of IoT in particular. Namely, we consider Wi-Fi, Bluetooth, ZigBee, and RFID wireless communication technologies. The paper also provides a taxonomy of these attacks based on a security service-based attack classification and discusses existing security defenses and mechanisms that mitigate certain attacks as well as the limitations of these security mechanisms.

ULTRAWIDEBAND ANTENNA IN WIRELESS COMMUNICATION: A REVIEW AND CURRENT STATE OF THE ART

Ultrawideband (UWB) systems offer a unique solution to attain high-speed short-range wireless communication and high precision location applications. Designing an UWB antenna with optimal characteristics is a major challenge because it needs to cover broader bandwidth, stable gain, good time-domain characteristics, and impedance matching over operational bandwidth. From the last decade, UWB technology is one of the key components of the research area and a lot of UWB antennas are designed and developed. The proposed paper highlights the promising applications and design challenges associated with the UWB antenna. It narrates the implications in developing planar UWB antenna and fine-tuning its parameters. The challenges, future perspective and wide range of UWB antenna applications are also discussed in this paper to make it useful for further research

Complex-Valued Neural Networks for Noncoherent Demodulation

Noncoherent demodulation is an attractive choice for many wireless communication systems. It requires minimal protocol overhead for carrier synchronization, and it is robust to radio impairments commonly found in low-cost transceivers. Machine learning techniques, such as neural networks and deep learning, offer additional benefits for these systems. Practical communication systems often include nonlinearities, non-stationarity, and non-Gaussian noise, which complicate mathematical derivation of optimum demodulators. Learning approaches can optimize demodulator performance directly from simulated or measured radio data, which is often plentiful in the design and verification of today’s integrated transceivers. This paper examines several candidate neural network topologies for use in noncoherent demodulation and provides a mathematical framework for their comparison. Each is based on a complex-valued feature detection layer, which may be characterized as coherent or noncoherent, followed by one or more real-valued classification layers. Backpropagation equations for the noncoherent feature layer include a synchronization term that facilitates training with noncoherent input data. The coherent layer does not synchronize training data, however a noncoherent demodulator can still be constructed by increasing the coherent layer capacity and adding a max pooling layer to marginalize the unknown signal phase. A frequency classification example highlights the differences between the topologies and confirms that optimum noncoherent demodulation can be learned in the presence of AWGN and random phase offsets. The topologies considered here are suitable for noncoherent demodulation of power-efficient modulations such as FSK and ASK, which are typical in today’s short-range wireless communication systems. It is hoped that such topologies will lead to a future common architecture that can support the wide range of modulation formats in this space.

Antenna Selection and Designing for THz Applications: Suitability and Performance Evaluation: A Survey

Imperceptible latency, uninterrupted communication, and the availability of inexhaustible bandwidth are conceptualized as essential milestones to revolutionize the modes by which societies generated, circulate, receive, and perceive information. The exponential increase in wireless data traffic has raised concerns to investigate suitable bands in the radio spectrum to satisfy the intensifying user's data rate requirements. Overall the wireless infrastructure needs development and exploitation to synchronize with the massive capacity and connectivity demands. The Terahertz (THz) frequency band (0.1-10 THz) is considered as a pivotal solution to fulfill the needs of applications and devices requiring the high speed transmission, and have received noticeable attention from the research community. Technologies in this spectrum are facing rapid development and hold high potentials in applications like ultra-fast short-range wireless communications, remote sensing, biological detection, and basic material research. The antenna is one of the critical components to support the THz systems and require a considerable attention in terms of precision. Compact high-gain antennas are desirable for low latency and high data rate THz wireless communication systems, specifically for applications having space limitation, for example, in the high speed interlink inside the high density wireless communication base station (BS). Nevertheless, there still exist many challenges, while designing the antenna for THz communications requiring innovative solutions. This paper serves an introductory guideline to address the challenges and opportunities, while designing a THz enabled antenna.

Design and Implementation of an IoT-Based Indoor Air Quality Detector With Multiple Communication Interfaces

Indoor air quality (IAQ) monitoring has attracted increasing attention with the rapid development of industrialization and urbanization in the modern society as people typically spend more than 80% of their time in indoor environments. A novel IAQ detector (IAQD) integrated with multiple communication interfaces has been designed, built, programmed, deployed, and tested in order to meet the requirements of wide variety of scenarios. The IAQD measures the IAQ data, including temperature, humidity, CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , dust, and formaldehyde timely. With state-of-the-art Internet of Things (IoT) technologies, the IAQD is integrated with Modbus, LoRa, WiFi, general packet radio service, and NB-IoT communication interfaces, which enables to be applied to wired communications, short-range wireless communications, and remote transmission to the cloud. The designed software in cloud allows users to track the IAQ of their home or office or industries everywhere. The performance IAQD is evaluated in terms of packet loss rate and time delay. The evaluation of IAQD are demonstrated and analyzed within the office environment over a week. Experimental results show that the proposed system is effectiveness in measuring the air-quality status and provide excellent consistency and stability.

Short-range optical wireless communications for indoor and interconnects applications

Optical wireless communications have been widely studied during the past decade in short⁃range applications, such as indoor high⁃ speed wireless networks and interconnects in data centers and high⁃performance computing. In this paper, recent developments in high⁃speed short⁃range optical wireless communications are reviewed, including visible light communications (VLCs), infrared in-door communication systems, and reconfigurable optical interconnects. The general architecture of indoor high⁃speed optical wire⁃ less communications is described, and the advantages and limitations of both visible and infrared based solutions are discussed. The concept of reconfigurable optical interconnects is presented, and key results are summarized. In addition, the challenges and potential future directions of short⁃range optical wireless communications are discussed.

Examination and Design of Bi-Phase Encoder for Short Range Wireless Communication

In today’s digital era, Communication systems have become ubiquitous in our everyday life. In data communication various protocols are employed to encode information bits in short range wireless communication technologies. Different types of baseband encoding schemes have been in practice for improving performance of communication which comprises of Manchester, differential Manchester and FMO codes.The transmitted signal is predicted to have zero mean for vigor issue and this is also called as dc balance. The design has been tested in Tanner EDA Tool using different logics such as CMOS logic, Pass Transistor logic and transmission gate logic.

Acoustic-Based Security: A Key Enabling Technology for Wireless Sensor Networks

Technological advances have proliferated in several sectors by developing additional capabilities in the field of systems engineering. These improvements enabled the deployment of new and smart products. Today, wireless body area networks (WBAN) are commonly used to collect humans’ information, hence this evolution exposes wireless systems to new security threats. Recently, the interest by cyber-criminals in this information has increased. Many of these wireless devices are equipped with passive speakers and microphones that may be used to exchange data with each other. This paper describes the application of the watermark-based blind physical layer security (WBPLSec) to acoustic communications as unconventional wireless link. Since wireless sensors have a limited computation power the WBPLSec is a valuable physical layer standalone solution to save energy. Actually, this protocol does not need any additional radio frequency (RF) connection. Indeed, it combines watermarking and a jamming techniques over sound-waves to create secure region around the legitimate receiver. Due to their nature, wireless communications might experience eavesdropping attacks. The analysis proposed in this paper, addresses countermeasures against confidentiality attacks on short-range wireless communications. The experiments over the acoustic air-gap channel showed that WBPLSec can create a region two meters wide in which wireless nodes are able to communicate securely. Therefore, the results favor the use of this scheme as a key enabling technology to protect the confidentiality in wireless sensor networks.

Smart Textile Integrated Wireless Powered Near Field Communication Body Temperature and Sweat Sensing System

Near field communication (NFC) is a short-range wireless communication technique that has become an attractive device for healthcare and wellbeing monitoring. The work reported here demonstrates the development of a battery free wearable sensing system with temperature and sweat sensors embedded into and powered by a smart textile NFC antenna. The NFC antenna is seamlessly integrated with closed-body garments, and the sensor data can be easily acquired by NFC readers and smart phones in order to achieve real time and wireless monitor of health status in a convenient and nonintrusive way. A Dickson charge pump circuit has been designed and implemented in order to pump up the voltage and ensure a steady voltage supply for the sweat sensor. The maximum read range for accessing sensor data is 6 cm. The on-body measurement accuracy of the temperature sensor and sweat sensor are able to achieve ±0.14 °C and ±0.2%, respectively. The presented system can provide wearable battery-free ubiquitous wireless connectivity for point-of-care and any time healthcare and wellbeing monitoring.

A Dual Interference-Canceling Active Quasi-Circulator Achieving 36-dB Isolation Over 6-GHz Bandwidth

Circulator is a key component in full-duplex wireless and radar detection systems. In this letter, a dual interference-canceling active quasi-circulator is proposed to enhance the isolation capability over the range of 1–7 GHz. The circulator is fabricated in the standard 0.18- $\mu \text{m}$ CMOS process occupying 1.03 mm $\times0.55$ mm including the pads. Measurement results demonstrate more than 36-dB isolation from the Tx to the Rx within 6-GHz bandwidth. The designed circulator is a good candidate for duplexers to allow the integrated transmitter and receiver to share a single antenna in the certain short-range wideband wireless communication systems, where noise figure (NF) is not strictly demanded but low cost and high integration are urgently required.

Survey and Perspectives of Vehicular Wi-Fi versus Sidelink Cellular-V2X in the 5G Era

The revolution of cooperative connected and automated vehicles is about to begin and a key milestone is the introduction of short range wireless communications between cars. Given the tremendous expected market growth, two different technologies have been standardized by international companies and consortia, namely IEEE 802.11p, out for nearly a decade, and short range cellular-vehicle-to-anything (C-V2X), of recent definition. In both cases, evolutions are under discussion. The former is only decentralized and based on a sensing before transmitting access, while the latter is based on orthogonal resources that can be also managed by an infrastructure. Although studies have been conducted to highlight advantages and drawbacks of both, doubts still remain. In this work, with a reference to the literature and the aid of large scale simulations in realistic urban and highway scenarios, we provide an insight in such a comparison, also trying to isolate the contribution of the physical and medium access control layers.

An Energy Efficient Multi-User Asynchronous Wireless Transmitter for Biomedical Signal Acquisition.

The paper presents a novel transmitter architecture for short-range asynchronous wireless communication, applicable to simultaneous multi-user wireless acquisition of biological signals. The analog signal, provided from an analog biosensor, is transformed to time information using an Integral Pulse Frequency Modulator (IPFM) as a Time-Encoding Machine. The IPFM generates a time-encoded unipolar pulse train, maintaining the linear dependence of the output pulse distance on analog input voltage. The system enables continuous acquisition of the signals from multiple sensors in which each transmitter has unique feedback loop delay used for multi-user coding. IPFM pulses trigger the Impulse Radio Ultra-Wideband pulse generator directly, providing two ultra-wideband (UWB) pulses per each IPFM pulse. Due to the lack of internal clock signal and microprocessor-free multi-user coding, the circuitry satisfies the requirements of multi-user coding energy efficiency and size reduction, which are crucial demands in biomedical applications. The proposed Time-Encoded UWB (TE-UWB) transmitter is implemented in 0.18 [Formula: see text] CMOS technology. Measurement results of the IPFM transfer function for input voltage ranging from 0.15 to 1.5 V are presented, providing the dependence of the IPFM pulse time distance on analog input voltage and power consumption dependence on the input voltage level. For continuous monitoring operation, total power consumption of the transmitter circuitry for the maximum input voltage is 10.8 [Formula: see text], while for the lowest input voltage it increases to 40.48[Formula: see text]. The circuit occupies 0.14 [Formula: see text].

Implementation of New Combiner for Indoor UWB Wireless Rake Receiver

In wireless systems, the multipath components (MPCs) are propagated through direct line of sight (LOS) and indirect non line of sight (NLOS). Multipath occurs due to reflection, diffraction, and scattering of transmitted signal. MPCs are considered one of the main problems in wireless communication system especially in ultra-wideband UWB system because these MPCs have a different amplitudes, phases, and delays with respect to the transmitted signals and cause signal distortions and fading that degrade the quality of the received signal and lead to poor performance in wireless communication systems. However multipath phenomena is used to enhance system performance by using a dedicated wireless receiver such as wireless rake receiver to resolve the MPCs and reduce multipath fading effects to improve system performance. The combiner is a main part of rake receiver and used to capture most of the energy of the received signal. Using this combiner, the system can achieve better performances that lead to maximize the average signal to noise ratio (SNR) to recover the transmitted signal with lower bit error rate (BER). This technique is suitable for UWB wireless devices that are commonly used for high-speed data rate through short-range indoor wireless communication. In this paper, a new combiner was proposed to enhance the combining performance of UWB wireless rake receiver named adaptive partial-hybrid (AP-H) combiner. For comparison, the two conventional combiners: selective combiner and partial combiner were designed. The simulation results were obtained by using MATLAB software; these results show higher system performance when using the proposed AP-H combiner than other conventional combiners. For this work, UWB signal was used with binary phase shift keying-Time Hopping (BPSK-TH) multiple access modulation scheme.