Wireless Transceiver Research Articles

Design of a Simulation and Evaluation System for Athlete Technical and Tactical Training Based on Virtual Reality Technology

In order to avoid the influence of external environmental factors on athletes’ physical fitness and technical tactics, the author proposes the design and research of an integrated simulation training system for athletes’ physical fitness and technical tactics based on virtual reality. The hardware unit of the design system includes a 3D scanner module, VR glasses module, locator module, tracker module, and wireless transceiver device. The software module introduces virtual reality technology and designs a visual simulation module, trained object detection module, trained object tracking module, and overall control module. The simulation experiment results show that compared with existing systems, the training scene output clarity and frame rate of the designed system are better, and the thread switching time and signal mixing time are shorter, which fully proves that the designed system has higher operating efficiency and better application performance.

Exploring distance-based wireless transceiver placements for wireless network-on-chip architecture with deterministic routing algorithms

Network-on-chip (NoC) technology is crucial for integrating multiple embed-ded computing cores onto a single chip. Consequently, this has led to the de-velopment of the wireless network-on-chip (WiNoC) concept, seen as a promis-ing strategy to overcome scalability issues in communication systems withinchips for future many-core architectures. This research analyses the impactof wireless transceiver subnet clustering on the hundred-core mesh-structuredWiNoC architecture. The study aims to examine the effects of distance-basedwireless transceiver placements on the transmission delay, network throughput,and energy consumption within a mesh wireless NoC architecture featuring ahundred cores, under specific routing strategies: X-Y, west-first, negative-first,and north-last. This research investigates the impact of positioning radio sub-nets at the farthest, farther, nearest, and closest positions within an architectureequipped with four wireless transceivers. The Noxim simulator was utilised tosimulate the analysed wireless transceiver placements within the hundred-coremesh-structured WiNoC designs, with the objective of validating the results.The architecture with the wireless transceivers positioned at midway proxim-ity (nearer and further) demonstrated the best performance, as evidenced by thelowest latencies for all evaluated deterministic routing algorithms, according tothe simulation outcomes.

Effects of electrical stimulation with alternating fields on the osseointegration of titanium implants in the rabbit tibia - a pilot study.

Introduction: Electrical stimulation has been used as a promising approach in bone repair for several decades. However, the therapeutic use is hampered by inconsistent results due to a lack of standardized application protocols. Recently, electrical stimulation has been considered for the improvement of the osseointegration of dental and endoprosthetic implants. Methods: In a pilot study, the suitability of a specifically developed device for electrical stimulation in situ was assessed. Here, the impact of alternating electric fields on implant osseointegration was tested in a gap model using New Zealand White Rabbits. Stimulation parameters were transmitted to the device via a radio transceiver, thus allowing for real-time monitoring and, if required, variations of stimulation parameters. The effect of electrical stimulation on implant osseointegration was quantified by the bone-implant contact (BIC) assessed by histomorphometric (2D) and µCT (3D) analysis. Results: Direct stimulation with an alternating electric potential of 150mV and 20Hz for three times a day (45min per unit) resulted in improved osseointegration of the triangular titanium implants in the tibiae of the rabbits. The ratio of bone area in histomorphometry (2D analysis) and bone volume (3D analysis) around the implant were significantly increased after stimulation compared to the untreated controls at sacrifice 84days after implantation. Conclusion: The developed experimental design of an electrical stimulation system, which was directly located in the defect zone of rabbit tibiae, provided feedback regarding the integrity of the stimulation device throughout an experiment and would allow variations in the stimulation parameters in future studies. Within this study, electrical stimulation resulted in enhanced implant osseointegration. However, direct electrical stimulation of bone tissue requires the definition of dose-response curves and optimal duration of treatment, which should be the subject of subsequent studies.

A hexagonal shape fractal flexible UWB antenna based on jeans material for healthcare applications

This work aims to provide a compact, flexible, lightweight ultra-wideband antenna design with enhanced bandwidth for medical applications. The proposed antenna features fractal geometry and is made by iterating a hexagonal slot within a circular copper construction. The basic radiator’s partial ground plane is defective with a slit at the centre and a down ramp on both sides of the plane. A stub in the feed line improves impedance matching and provides enhanced −10dB bandwidth of 10.6 GHz (1.9 GHz to 12.5 GHz). The antenna is built on a black jeans textile substrate of dielectric constant 1.7 and size of 48 mm × 36 mm × 1.7 mm . The maximum gain of 6.75 dB at the frequency of 2.3 GHz is reported. In the operational band, the developed antenna provides steady radiation properties. Furthermore, the antenna has been verified for use in practical applications by setting up the proposed antenna as a receiver with an NRF24L01 wireless transceiver module and given coverage up to 50 feet in an open environment. The designed prototype is analysed for flexibility with different bending radii. A SAR analysis is also carried out for 1 gram and 10-gram of tissue along with the extensive time domain analysis for wearable UWB applications.

Error analysis of OFDM‐IM systems for beyond 5G: The effect of IQI at transceiver

SummaryIt is well known that hardware impairments (HWIs) can worthy reduce the wireless system performance at high carrier frequencies by showing random effects. Most current researches for 5 GB systems assume that transmitters and receivers (transceivers) are perfectly equipped. But wireless transceivers ( ) are affected by HWIs in practice. Considering the previous studies in the literature, it is reported that HWIs have devastating effects on the performance of OFDM and OFDM‐index modulation (IM) systems with fading channels. In this paper, in‐phase and quadrature phase imbalance (IQI), which is the one of most HWIs between transmitter and receiver in wireless communication systems, is examined on OFDM‐IM system over Rayleigh and Nakagami‐ fading channels. Two well‐known detectors, the maximum likelihood (ML) detector and the log‐likelihood ratio (LLR) detector are used under the effect of the IQI at . Error performance analyzes over fading channels of the IQI effect on OFDM‐IM system are realized first theoretically and then by computer simulations. Results obtained for the presence of IQI at show that a performance evaluation based only on the presence of IQI in the receiver would be optimistic and misleading in terms of the performance of real‐life OFDM‐IM systems.

MSAIL: Milligram-Scale Multi-Modal Sensor Platform for Monarch Butterfly Migration Tracking

Each fall, millions of monarch butterflies across the northern US and Canada migrate up to 4,000km to overwinter in specific mountain peaks in central Mexico. To track monarchs precisely and study their navigation, a monarch tracker must obtain daily localization of the butterfly as it progresses on its three-month journey. And, the tracker must perform this task while having a weight in the tens of milligrams (mg) and measuring a few millimeters (mm) in size to avoid interfering with the monarch's flight. This paper proposes mSAIL, 8 × 8 × 2.6mm and 62mg embedded system for monarch migration tracking, constructed using 8 prior custom-designed ICs providing solar energy harvesting, an ultra-low power processor, light/temperature sensors, power management, and a wireless transceiver, all integrated and 3D stacked on a micro PCB with an 8 × 8mm printed antenna. The proposed system is designed to record and compress light and temperature data during the migration path while harvesting solar energy for energy autonomy, and wirelessly transmit the data at the overwintering site in Mexico, from which the daily location of the butterfly can be estimated using a deep learning-based localization algorithm. A two-day trial experiment of mSAIL attached to a live butterfly in an outdoor botanical garden demonstrates the feasibility of individual butterfly localization and tracking.

Secure UAV adhoc network with blockchain technology.

Recent advances in aerial robotics and wireless transceivers have generated an enormous interest in networks constituted by multiple compact unmanned aerial vehicles (UAVs). UAV adhoc networks, i.e., aerial networks with dynamic topology and no centralized control, are found suitable for a unique set of applications, yet their operation is vulnerable to cyberattacks. In many applications, such as IoT networks or emergency failover networks, UAVs augment and provide support to the sensor nodes or mobile nodes in the ground network in data acquisition and also improve the overall network performance. In this situation, ensuring the security of the adhoc UAV network and the integrity of data is paramount to accomplishing network mission objectives. In this paper, we propose a novel approach to secure UAV adhoc networks, referred to as the blockchain-assisted security framework (BCSF). We demonstrate that the proposed system provides security without sacrificing the performance of the network through blockchain technology adopted to the priority of the message to be communicated over the adhoc UAV network. Theoretical analysis for computing average latency is performed based on queuing theory models followed by an evaluation of the proposed BCSF approach through simulations that establish the superior performance of the proposed methodology in terms of transaction delay, data secrecy, data recovery, and energy efficiency.

Design and Simulation of VCO for RF Transceivers with Low Power, Low Phase Noise and Wider Tuning Range using Silterra 130nm CMOS Technology

The performance of low-power transceivers is required to meet stringent specifications for an advanced wireless radio frequency (RF) application. The design topology in this paper is simulated to meet the specifications and operation of VCO for low power, low phase noise and wide tuning range in complementary metal oxide semiconductor (CMOS) 130nm technology for RF transceivers. The relationship between the phase noise, power consumption and frequency turning range is fully analyzed to further improve the performance of the voltage-controlled oscillator (VCO). The architecture of the VCO employs two sets of symmetrical cross-couple split NMOS and PMOS with biased current sources operating in the triode region, and a resonator tank that achieves the desired low phase noise performance of about -110 dB/Hz at a tuning range of 4.1 to 4.5 GHz with a supply of 0.9 V. The control of the DC bias point reduces the conduction angle, which improves the current efficiency, power consumption and phase noise. The topology generates sufficient –gm for the oscillator incorporation to mitigate the start-up issue of the VCO. At the center frequency of 4.38 GHz, the VCO serves as a promising solution for improving low power and low phase for wireless communication systems and RF transceiver applications. The design consumes a very low power of 0.138 mW, achieves a phase noise of -110.53 dBc/Hz at 1 MHz offset, and a figure of merit (FoM) of -191.90 dBc/Hz.

Metasurface-based wireless communication technology and its applications

Metasurfaces, due to their outstanding ability to control electromagnetic waves, have great application prospects in the field of wireless communication. This paper provides a comprehensive review of research work based on metasurface in three aspects: wireless power transfer, wireless information transmission, and novel wireless transceiver architectures. In the domain of wireless power transfer, several focusing metasurfaces and systems with unique performance are presented along with a new formula for calculating wireless power transfer. Concerning wireless information transmission section, the direct digital information transmission based on metasurface and the information transmission based on space-time-coding digital metasurface are introduced. Lastly, a simplified wireless transceiver with metasurfaces was introduced. The paper concludes with a discussion on the future directions of metasurfaces in the wireless communication domain.

Graphene nanomechanical vibrations measured with a phase-coherent software-defined radio

Software-defined radios (SDRs) are radio frequency transceivers designed to facilitate digital signal processing through the use of vast libraries of open-source software. Here, we assemble a simple data acquisition system whose architecture, based on SDR, allows us to develop a comprehensive suite of tools to study the vibrations of a few-layer graphene nanomechanical resonator. Namely, we measure the cross-spectrum of vibrations in the frequency domain, we measure their energy decay rate in the time domain, we perform vector measurements of their in-phase and quadrature components, and we control their phase using a time-dependent strain field –all with a single measurement platform. Our approach allows us to tailor our experiments at will and gives us control over every stage of data processing. Overall, our versatile system enables measuring a wide range of nanomechanical properties of graphene by customizing the signal acquisition and replacing some analog electrical circuits, such as filters, mixers, and demodulators, by blocks of code.

A Reliable Algorithm for Efficient Water Delivery and Smart Metering in Water-Scarce Regions

Smart water meters play a significant part in the interactive control of water supply networks required for smart cities. Opposed to completely mechanical water meters, electro-mechanical water meters or fully electronic water meters can capture real-time data via an automated meter reading process, making them more appropriate for smart city applications. However, the depletion of fresh water supplies as a result of climate change, as well as the rising demand associated with population increase, are some growing concern in many regions globally. Monitoring water distribution and delivery is a critical strategy for increasing distribution efficiency. This paper presents a wireless transceiver unit that can be integrated with existing electronic water meters. The unit utilises a reliable communication algorithm for real-time data exchange. Metering data is transmitted using cutting-edge narrow-band Internet of Things technology that operates using low power whilst covering a wide range with effective penetration.

ACTIVE TRANSMITTER SIGNAL CANCELLATION IN RECEIVE SIGNAL PATH FOR SDR

Elimination of receiver (RX) band-pass filters is actual task for construction of next generation New Radio Wireless Transceivers and other modern equipment (Multiple Input Multiple Output systems, radar applications, etc.) based on software-defined radio. Unfortunately, some new problems with electromagnetic compatibility arise. Main problem start up with Frequency Division Duplex mode, were part of high power transmitter (TX) signal came to high sensitivity RX input through duplexer with limited isolation. In presence of high TX signal RX mixer could come into non-linear working area and RX sensitivity is decreases. This problem may be solved by cancellation of TX signal from RX path. This article provides a preliminary approach to the problem of active TX signal cancellation in RX signal path with cancellation is at least 25 dB, and relatively small additional power consumption and noise. After critical parameters identifying, based on mathematical expressions, the requirements for cancellation blocks parameters are determined. Simplest implementations of the proposed structure are simulated.

Distributed Model Predictive Control via Separable Optimization in Multiagent Networks

We present a distributed model predictive control method which enables a group of agents to compute their control inputs locally, while communicating with their neighbors over a communication network. While many distributed model predictive control methods require a central station for some coordination or computation of the optimization variables, our method does not require a central station, making our approach applicable to a variety of communication network topologies. With our method, each agent solves for its control inputs without solving for the control inputs of other agents, allowing for efficient optimization by each agent, unlike some other distributed methods. Further, our method attains linear convergence to the optimal control inputs in convex model predictive control problems, improving upon the sub-linear convergence rates provided by some other distributed methods such as dual decomposition methods. Moreover, our algorithm provides a closed-loop controller for convex model predictive control problems with affine constraints. We demonstrate our method in both convex and non-convex model predictive control problems in wireless transceiver alignment and satellite deployment, where we show robustness of our method to time delays.

Signal Processing Algorithms for Mean Square Error Analysis in MIMO Wireless Transceivers

Signal Processing Algorithms for Mean Square Error Analysis in MIMO Wireless Transceivers

CMOS Wireless Hybrid Transceiver Powered by Integrated Photodiodes for Ultra-Low-Power IoT Applications

In this article, a communication platform for a self-powered integrated light energy harvester based on a wireless hybrid transceiver is proposed. It consists of an optical receiver and a reconfigurable radio frequency (RF) transmitter. The hybrid optical/RF communication approach improves load balancing, energy efficiency, security, and interference reduction. A light beam for communication in the downlink, coupled with a 1 MHz radio frequency signal for the uplink, offers a small area and ultra-low-power consumption design for Smart Dust/IoT applications. The optical receiver employs a new charge-pump-based technique for the automatic acquisition of a reference voltage, enabling compensation for comparator offset errors and variations in DC-level illumination. On the uplink side, the reconfigurable transmitter supports OOK/FSK/BPSK data modulation. Electronic components and the energy harvester, including integrated photodiodes, have been designed, fabricated, and experimentally tested in a 0.18 µm triple-well CMOS technology in a 1.5 × 1.3 mm2 chip area. Experiments show the correct system behavior for general and pseudo-random stream input data, with a minimum pulse width of 50 µs and a data transmission rate of 20 kb/s for the optical receiver and 1 MHz carrier frequency. The maximum measured power of the signal received from the transmitter is approximately −18.65 dBm when using a light-harvested power supply.

An Uplink Cooperative NOMA Based on CDRT With Hardware Impairments and Imperfect CSI

Hardware impairments in wireless transceivers can cause severe performance degradation, particularly for high-rate communication networks. Few studies have explored the impact of these frameworks on recent wireless networks, such as uplink nonorthogonal multiple access (NOMA) with imperfect channel estimation. In this article, we investigate the effect of two practical and malignant imperfections on the performance of coordinated direct and relay transmission (CDRT) using uplink NOMA. Based on these imperfections, we derive an exact closed-form expression for the ergodic sum capacity and outage probability of an uplink NOMA CDRT network. Our model accounts for all the hardware distortions caused by nonideal transceiver nodes as well as residual interference from imperfect channel estimates and imperfect successive interference cancellations. Furthermore, in order to establish a benchmark, we provide analytical expressions and numerical results that demonstrate the superiority of the CDRT-assisted uplink NOMA system with respect to an orthogonal multiple access system. To verify the accuracy of the derived analytical expressions, Monte Carlo simulations are performed.

IQ Imbalance Correction in Wideband Software Defined Radio Transceivers

IQ Imbalance Correction in Wideband Software Defined Radio Transceivers

Measuring Received Signal Strength of UWB Chaotic Radio Pulses for Ranging and Positioning

The use of ultra-wideband (UWB) signals for local positioning is very attractive for practice, because such signals have the potential to provide centimeter precision. In this paper, we consider wireless ranging (distance measurement) and positioning, using one of the kinds of UWB signals, i.e., chaotic radio pulses, which are noise-like signals with no constant shape. The distance measurement is based on an assessment in the receiver of the power of UWB chaotic radio pulses emitted by the transmitter. A new method for estimating their power and its experimental implementation is proposed and described. Experimental layouts of the transmitter and receiver and the principles of their operation are described. To determine the main features of this method under real signal propagation conditions, full-scale indoor measurements were carried out, and statistical estimates of the accuracy were made. We present the results of experimental testing of the proposed approach for positioning the emitter relative to a system of anchors in an office space 6 × 6.5 m2 in the mode of measuring object coordinates on a line and on a plane. The mean absolute error (MAE) of distance measurement (1D) was 25 cm, and the root mean squared error (RMSE) was 39 cm. When positioning on a plane (2D), the MAE of coordinate estimation was 34 cm and the RMSE was 42 cm. The proposed distance measurement method is intended for use in wireless UWB transceivers used in wireless sensor networks.

A 1-V 9.6-GHz charge-pump PLL with low RMS-integrated jitter

A low-power low-jitter phase-locked loop (PLL) with phase noise improvement for radio frequency transceivers is presented in this paper. The in-band phase noise and out-of-band phase noise are both reduced due to the time-amplifying technique and the class-C voltage-controlled oscillator (VCO), respectively. In addition, a low current mismatch charge pump (CP) is used here to guarantee a low reference spur. The proposed PLL is fabricated in a 65-nm CMOS mixed-signal process with an area of 0.220 mm2, and the reference clock is 150 MHz. The measurement results show that this PLL operates at 1-V supply voltages and achieves 8.5–10.3-GHz tuning range, 407.807-fs integrated jitter at 9.6 GHz, 7.20-mW total power consumption, resulting in a −239.22-dB figure-of-merit (FoM). The measured reference spur is −51.27 dBc at a 150-MHz offset frequency.

Performance Evaluation of VANET using Directional Location Aided Routing (D-LAR) Protocol with Sleep Scheduling Algorithm

Neighboring radio networks are those that do not instantly supply communications infrastructure after deployment, have radio transceivers with restricted transmission range, and are unaware of possible neighbors. Vehicle-to-vehicle communication is an effective means to convey information through an asymmetric vehicle ad hoc network, and it can provide high security while also reducing energy usage. A new protocol is known as energy efficiency, the D-LAR (Directed Location Assist) protocol, is used to determine a node's energy efficiency. To determine the sleep and active states of nodes, propose a sleep scheduling technique. It can also provide a more accurate location of a moving vehicle than existing location support protocols. In comparison to other current systems, the simulation results suggest that the proposed D-LAR technique has the advantages of decreasing the collision attack detection delay time and enhancing security.