Short-range Wireless Systems Research Articles

Numerically Optimized Fourier Transform-Based Beamforming Accelerated by Neural Networks

Conventional beamforming methods for reconfigurable reflector antennas assume full control over the amplitude and phase of the reflected field. Here, we develop a novel beamforming methodology for reflecting Programmable Metasurfaces (PMS) with capacitive memory. Although utilizing such fully reactive PMS simplifies antenna design and reduces energy consumption, the PMS reflection magnitude is unity and thus a global optimization of the reflection phases over the PMS unit cells is required in each beamforming scenario. We propose an implementation of such an optimization method rooted in the traditional Fourier transform-based beamforming and evaluate its performance. Additionally, we show that a pair of trained feed-forward neural networks (FFNN) with one input, one hidden, and one output layer can replace time-consuming global optimizations in the case of a PMS comprising 3×10 unit cells. We train the FFNNs on a dataset obtained for typical single- and dual-beam beamforming scenarios. After training, the FFNNs perform requested beamforming tasks within a fraction of second and with about the same accuracy as the original optimization algorithm. The proposed methodology may find applications in future mobile telecommunication systems that require real-time beamforming on low-end hardware. The same beamforming methodology can be also employed in short-range wireless power transfer systems.

Investigations of the Wireless M-Bus System Resilience under Challenging Propagation Conditions

Wireless M-Bus is a short-range wireless telemetry system that plays a vital role in the capillary sector of the Internet of Things (IoT) ecosystem. Similar to any other IoT technology, it is meant to operate in harsh environmental conditions such as production plants, cellars, or other under-ground or indoor metering installations. This paper describes the methodology and outcomes of a carefully designed measurement campaign targeted at investigating this system’s immunity to jamming and extremely fading channels. The former was carried out in an anechoic chamber and the latter in a reverberation chamber, both specifically adapted for these types of measurements. The presented methodology allows for reproducible research. The article demonstrates PER measurements results as a function of CNIR for all throughput modes offered by the tested devices (ranging from 4.8 kb/s to 100 kb/s). The threshold CNIR values are universal and may prove useful in an IoT network design that is based on the Wireless M-Bus technology.

Perfectly matched inhomogeneous receiving metasurface for line source incidence

This paper presents a perfectly matched inhomogeneous receiving metasurface for line source incidence, based on the effective medium equivalency. Each building block of the inhomogeneous metasurface has effective constitutive parameters that satisfy a specific relationship dependent on the location of the line source. By doing so, the reflection from the receiving metasurface for the cylindrical wave incidence can be significantly suppressed, improving the total reception efficiency greatly. Theoretical analysis, numerical calculation, full-wave simulations and experimental results are consistent with each other, showing promising applications in some short-range wireless power transmission systems, where the incident wave is non-planar.

Mechanism to Estimate Effective Spectrum Availability Inside Smart Buildings

Smart cities and smart buildings must provide their customers with many services, including those associated with health, productivity, and energy efficiency, among others. Short-range wireless systems can provide all of these services, but the significant growth of wireless networks operating within a smart building (SB) can produce the phenomenon of spectrum shortages. Spectrum shortages could be resolved using Cognitive Radio (CR)-based systems to improve the efficiency of electromagnetic spectrum use by taking advantage of the reusable spectrum available in the building’s interior. This study proposes a mechanism using two interference conditions to quickly estimate the minimum amount of effective spectrum availability (ESA) inside an SB. The results show that an SB contains ESA distributed across 36% to 98% of the building’s area for reuse, as a function of the height of the building and of the distance from the base station (BS) of the primary system.

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.

A Wide-Angle Scanning Switched-Beam Antenna System in LTCC Technology With High Beam Crossing Levels for V-Band Communications

Wide-angle coverage, fine angular resolution, and low-power consumption are the key characteristics of millimeter-wave short-range wireless systems, such as access points in fifth-generation cellular networks and automotive radars. In this paper, we present a 60 GHz switched-beam antenna system addressing all these requirements. It consists of two identical parallel-fed arrays of eight slots, each fed by a passive pillbox beamformer. A switch network comprising four single-pole-multiple-throw switches excites one of the two arrays at a time and selects the radiated beam. The whole system is fully integrated into a multilayer low-temperature cofired ceramic module. The antenna covers a scan range of about ±39° in one plane using 11 beams between 57 and 66 GHz. The proposed architecture enables the simultaneous achievement of continuous coverage (beam crossover levels of about −3 dB) and of low sidelobe levels. Dedicated numerical tools are used for a preliminary design of the antenna. The design procedure, the technological development, and the experimental results are discussed in detail.

Solver Device for Powdery Drugs.

Pharmacotherapy is a major treatment method in healthcare centers, and the injection of powdered drugs is among common pharmacotherapy techniques. Medication errors and nosocomial infections are among major health issues in the world. On the other hand, powdered drugs are widely used in hospitals; however, drug mixture is a very time-consuming process. The objective of this invention was to accelerate drug vial mixture, reduce medication errors and nosocomial infections, and save time. There are different drug mixing devices, each with specific abilities. The present invention not only possesses the abilities of other devices but also can mix drugs [with a diluent] with higher quality and accuracy. The drug vial mixing device can mix 20 vials at adjustable time and speed with high quality and accuracy. This device is equipped with an infrared system to ensure a complete mixture of powder, and a Bluetooth short range radio system to remotely control all monitoring options of the device. This is a small and simple-to-use device. The drug vial mixing device can effectively reduce medication errors and nosocomial infections, and save time.

Smart Sensor Systems for Wearable Electronic Devices.

Wearable human interaction devices are technologies with various applications for improving human comfort, convenience and security and for monitoring health conditions. Healthcare monitoring includes caring for the welfare of every person, which includes early diagnosis of diseases, real-time monitoring of the effects of treatment, therapy, and the general monitoring of the conditions of people’s health. As a result, wearable electronic devices are receiving greater attention because of their facile interaction with the human body, such as monitoring heart rate, wrist pulse, motion, blood pressure, intraocular pressure, and other health-related conditions. In this paper, various smart sensors and wireless systems are reviewed, the current state of research related to such systems is reported, and their detection mechanisms are compared. Our focus was limited to wearable and attachable sensors. Section 1 presents the various smart sensors. In Section 2, we describe multiplexed sensors that can monitor several physiological signals simultaneously. Section 3 provides a discussion about short-range wireless systems including bluetooth, near field communication (NFC), and resonance antenna systems for wearable electronic devices.

Demonstration of 60 GHz millimeter-wave short-range wireless communication system at 3.5 Gbps over 5 m range

Millimeter-wave communication has received considerable attention for use in new-generation broadband wireless communication because of the scarcity of microwave band spectrum resources. The unlicensed frequency band at 60 GHz is suitable for indoor short-range broadband communication. In this paper, we introduce a 60 GHz millimeter-wave short-range wireless communication demo system adhering to the IEEE 802.11ad standard and targeting high-definition video streaming transmission. The system uses single-carrier transmission with frequency-domain equalization. The hardware prototype consists of a 65-nm CMOS radio-frequency front-end and a baseband transceiver for the physical layer functions. Important baseband technologies such as carrier synchronization, phase noise compensation, frequency-domain equalization, and low-density parity-check decoding based on probability calculation are also discussed. The system performance is demonstrated in an experiment on high-definition video transmission, where a data rate of 3.52 Gbps is achieved with a quadrature phase-shift keying signal over a distance of 5.109 m.

Frequency Split Elimination of Short Range Wireless Power Transfer System by Active Matching Tuning Circuit

Objective: The main theme of this paper is to eliminate the frequency split in short range Wireless Power Transfer (WPT) system by magnetic resonance coupling. Analysis: The common basic two coils based magnetic resonance WPT system is taken for the analysis; the frequency and transfer coefficient are plotted for different dimensions of the coil. Using genetic algorithm, the lumped impedance parameters are determined, which is used for the tuning of the active matching circuit. Based on the experimental results it has been observed that the frequency split can be eliminated by tuning the matching circuit properly for the corresponding distance and higher efficiency can be achieved for short range. Findings: The frequency split elimination techniques can be used in dynamic transmitter and receiver wireless charging system. Application: This system can be employed in short range wireless power transfer such as neural implants, capsule robots, micro-robots and electric vehicle charging and so on.

Semi-physical simulation method and technology for on-board phase-Doppler short-range radio systems

The article examines methods and technology behind semi-physical simulation of short-range radio systems, accounting for performance features and usage specifics of on-board phase-Doppler systems. An example of implementing a semi-physical test bench is shown, along with its structural and functional chart and a sample of simulation results for one of the short-range radio systems.

Energy Efficient Cooperative Communication with Grouped Relay in MB-OFDM for UWB Systems

Ultra Wide Band (UWB) technology is a fast emerging technology for short distance wireless communication. UWB plays a preeminent role in the short range wireless systems, due to the advantages of high speed, low power consumption and very high security. Methods/Statistical Analysis: With cooperative communication as a decisive member in its side this paper proposes cooperative MB-OFDM communication using effective grouped relays in multichannel with use of Dual Carrier Modulation (DCM) for UWB systems. We can attain maximum diversity by using simple Maximum Likelihood (ML) receiver without reduction of data rate as its found using almounti coding which is most used to provide diversity in cooperative communication. Findings: The Proposed method’s resulting diversity is observed using outage probability as a basic parameter and also how the outage probability varies in accordance to threshold power. Application/Improvements: The results shows an improved BER versus SNR with effect of CFO is considered and the improvement in channel capacity and data rate of various different modulation schemes is obtained by varying SNR and distance.

The road to 100 Gb/s wireless and beyond: basic issues and key directions

This work addresses the blueprint of shortrange wireless systems supporting data rates of 100 Gb/s and beyond. A number of usage models are identified for such ultra-high data rates, including wireless communication within electronic equipment enabling possibilities such as wireless reconfigurable chip-to-chip communication. The 300 GHz band spanning about 55 GHz of contiguous bandwidth is identified as the most suitable candidate to accommodate these bandwidth- demanding applications. Furthermore, the main bottleneck issues are discussed: power consumption and antenna integration. With the help of basic link budget considerations, we indicate the technical feasibility of the proposed concept with compact low-cost antenna solutions. Finally, we discuss the overall system architecture to be standardized and indicate a number of key research topics.

On Calibrating the Sensor Errors of a PDR-Based Indoor Localization System

Many studies utilize the signal strength of short-range radio systems (such as WiFi, ultrasound and infrared) to build a radio map for indoor localization, by deploying a large number of beacon nodes within a building. The drawback of such an infrastructure-based approach is that the deployment and calibration of the system are costly and labor-intensive. Some prior studies proposed the use of Pedestrian Dead Reckoning (PDR) for indoor localization, which does not require the deployment of beacon nodes. In a PDR system, a small number of sensors are put on the pedestrian. These sensors (such as a G-sensor and gyroscope) are used to estimate the distance and direction that a user travels. The effectiveness of a PDR system lies in its success in accurately estimating the user's moving distance and direction. In this work, we propose a novel waist-mounted based PDR that can measure the user's step lengths with a high accuracy. We utilize vertical acceleration of the body to calculate the user's change in height during walking. Based on the Pythagorean Theorem, we can then estimate each step length using this data. Furthermore, we design a map matching algorithm to calibrate the direction errors from the gyro using building floor plans. The results of our experiment show that we can achieve about 98.26% accuracy in estimating the user's walking distance, with an overall location error of about 0.48 m.

MULTIPLE-INPUT MULTIPLE-OUTPUT TRANSMISSION OVER A MULTIPATH FADED CHANNELS

The use of multiple antennas at the transmitter as well as at the receiver can greatly improve the capacity of a wireless link when operating in a rich scattering environment. In such an arrangement all transmitting antennas radiate in the same frequency band so the overall spectral efficiency becomes very high. Such a multiple antenna scheme, popularly known as Multiple Input Multiple Output (MIMO) has potential application in Wireless Local Area Networks (WLAN) and cellular micro-cells. One reason is that the WLANs and other short range wireless systems often operate in an indoor environment, which offers rich scattering. The other reason is the demand for higher data rates in cellular and WLAN systems to scater for multimedia services. Also to meet the requirement of very high data rates for wireless Internet and multimedia services, multiple transmitting and multiple receiving antennas have been proposed for fourth generation wireless systems. In cellular systems, performance is limited by fading and co channel interference from other users. Most of the current studies on Multiple-Input Multiple-Output (MIMO) systems assume that the co-channel interference is both spatially and temporally white. Recently researchers have proposed different architectures for materializing the potential of the MIMO scheme. We consider three different types of channels: AWGN, Rician fading and Rayleigh fading. The entire work will be simulated in the Monti Carlo simulations. The main contribution of this study includes: A comparative study and a head to head comparison of the different modulation types based MIMO systems. The application of adaptive modulation in the MIMO system will be considered.

Ultralow Power Injection-Locked GFSK Receiver for Short-Range Wireless Systems

This brief presents a novel CMOS Gaussian frequency-shift keying (GFSK) receiver with an ultralow power consumption, which is based on the injection-locking technique for short-range wireless systems. Additionally, through reducing the oscillation current amplitude of the injection-locked oscillator, the GFSK receiver sensitivity is significantly improved. While comprising a submilliwatt low-noise amplifier, a trifilar transformer splitter, and an injection-locked self-oscillating mixer, the proposed receiver is fabricated using a 90-nm CMOS 1P9M technology. Measurement results indicate a sensitivity of -81 dBm, with a power consumption of 1.8 mW, when a Bluetooth GFSK signal with a data rate of 1 Mb/s is received.

The Roundup

The Roundup

A 60GHz CMOS Transceiver IC for a Short-Range Wireless System with Amplitude/Phase Imbalance Cancellation Technique

A 60GHz CMOS Transceiver IC for a Short-Range Wireless System with Amplitude/Phase Imbalance Cancellation Technique

Frequency-Domain Analysis of Super-Regenerative Amplifiers

Since its invention in 1922, the super-regenerative amplifier (SRA) has been used in a variety of short-range, low-power, and/or low-cost wireless systems due to its simple implementation and excellent performance for a given power budget. Growing demand for ultralow-power receivers for short-range radios has recently reawakened an interest in the theory and design of SRAs. Building on recent work and using reasonable assumptions and approximations, we present a frequency-domain model for analyzing SRAs. We then use these models to predict the response of an SRA to arbitrary deterministic and stochastic signals including sinusoids, pulsed-sinusoids, and additive white Gaussian noise. Using the results, we present formulas for calculating the sensitivity and selectivity of SRAs. We also introduce the concept of a trigger-time that is particularly useful for accurately determining the optimal threshold in on-off keying (OOK) receivers and helps avoid the problems introduced by nonlinearity in SRAs. Finally, we present a prototype OOK SRA that achieves a sensitivity of -90 dBm at a bit rate of 300 kbps (BER of 10-3) while consuming 500 ?W, and show that its measured sensitivity matches theory within 1 dB.

Vehicle Infrastructure Integration Test Beds Planned for Detroit

In this article, the author describes a number of tests conducted by the Michigan Department of Transportation (MDOT) regarding Vehicle Infrastructure Integration (VII). The tests, conducted in the Detroit area, collect vehicular information such as speed of travel, road surface conditions, windshield wiper use, air temperature, and shock and antilock brake use. Intelligent Transportation Systems (ITS) concepts such as VII are implemented in order to increase both mobility and safety. Using a dedicated short-range radio system (DSRC), which links cars to one another via vehicle-to-vehicle as well as to wayside hubs, researchers hope to determine whether a fast moving vehicle can engage in local wireless network communications as effectively as stationary objects. Other such VII tests are being conducted in the San Francisco Bay Area by the California Department of Transportation (Caltrans) and the University of California, Berkeley.