Wire Channel Research Articles

A Low-Power Impedance-to-Frequency Converter for Frequency-Multiplexed Wearable Sensors.

We propose a low-power impedance-to-frequency (I-to-F) converter for wearable transducers that change both its resistance and capacitance in response to mechanical deformation or changes in ambient pressure. At the core of the proposed I-to-F converter is a fixed-point circuit comprising of a voltage-controlled relaxation oscillator and a proportional-to-temperature (PTAT) current reference that locks the oscillation frequency according to the impedance of the transducer. Using both analytical and measurement results we show that the operation of the proposed I-to-F converter is well matched to a specific class of sponge mechanical transducer where the system can achieve higher sensitivity when compared to a simple resistance measurement techniques. Furthermore, the oscillation frequency of the converter can be programmed to ensure that multiple transducer and I-to-F converters can communicate simultaneously over a shared channel (physical wire or virtual wireless channel) using frequency-division multiplexing. Measured results from proof-of-concept prototypes show an impedance sensitivity of 19.66 Hz/ Ω at 1.1 kΩ load impedance magnitude and a current consumption of [Formula: see text]. As a demonstration we show the application of the I-to-F converter for human gesture recognition and for radial pulse sensing.

EFFECT OF THICK VEGETATION COVER, BUILDING OBSTRUCTIONS, AND EARTH TERRAIN ON THE QUALITY AND PERFORMANCE OF THE GSM SIGNAL AT THE FEDERAL POLYTECHNIC ADO-EKITI

Wireless communication system performance is fundamentally constrained by the mobile radio channels such as the Global System for Mobile Communication (GSM). The transmission path between the base transceiver station and the mobile station can range from line-of-sight to substantially obstructed environmental situations such as buildings, earth undulation valleys, and thick vegetation being the primary cause of poor network performance in and around the school perimeter. Mobile radio channels are incredibly unpredictable and do not provide simple analysis, in contrast to stationary and reliable wired channels. This research work, therefore, investigates the effect of thick vegetation cover, building obstructions, and earth terrain on the quality and performance of the GSM signal at the Federal Polytechnic Ado-Ekiti environs. A model for path loss (attenuation) is developed according to the Longley-Rice propagation model that forecasts the long-term median transmission loss over uneven terrain in comparison to the free-space transmission loss. The model was created for frequencies in the 20 MHz to 40 GHz range and path lengths in the 1 to 2,000 km range. The analysis of the results obtained shows that the path loss (attenuation) produced due to the effect of vegetation, building obstructions, and the earth undulation structures are quite significant. The solution of cell creation as a primary way of improving the quality of the GSM signal reception in the school perimeter without necessarily destroying the natural environment or demolishing any existing building is proposed.

Decision Algorithm Based on the Modified Bellman Equation to Deal With EMI-Induced Errors in Hamming-Based Communications

This article presents a decision-making algorithm based on a modified version of the Bellman equation to deal with electromagnetic interference errors in a communication channel inside a harsh electromagnetic reverberant environment. The Bellman equation is a fundamental concept in decision-making problems such as Markov decision processes. Such processes model decision making in situations where the outcomes are partly random and partly controlled by an agent (decision maker). Recent studies have implemented Markov decision processes as a tool for risk assessment in areas such as robotics or aviation. However, so far, no research has been reported that uses the Bellman equation or Markov decision processes to deal with risks related to electromagnetic disturbances. In our study, a wired communication channel that uses non-return-to-zero-level data encoding and Hamming code for error detection and correction is disturbed. First, the packet error rate (PER) is calculated and compared with and without the proposed algorithm for different electromagnetic disturbance frequencies and bit rates. The gain is compared at different PERs when the algorithm's parameters (called rewards) are optimized and when these are set as random. Finally, the influence of the rewards and the maximum number of resends on the algorithm's performance is also studied.

Advanced Design of a Robust and Effective EMI Detector for Wired Communication Channels

In this letter, an advanced design of an electromagnetic interference (EMI) detector for wired communication channels is proposed and analyzed. A Monte-Carlo-based simulation framework is used to evaluate the performance of the EMI detector under harsh electromagnetic environments. Based on this analysis, it is concluded that the proposed advanced EMI detector works effectively as long as the two involved data transmission lines are sufficiently close to each other.

Experiments on direct chaotic differentially coherent data transmission in a wired communication channel

Methods of differentially coherent information transmission using noise signals are of interest because of the impossibility of implementing the known methods of correlation reception for such signals. With a potentially higher noise immunity compared to the methods of information transmission based on chaotic synchronization, however, they have a feature that does not allow transceivers to be implemented in practice. The transmitter and receiver of the scheme, based on already known methods of differentially coherent transmission, require a time delay comparable to the duration of the transmitted bits. With an analog implementation of the scheme this leads to a physical length of the delay line of tens of meters or more. Previously, the authors proposed and studied a differentially coherent transmission scheme in which there are no long delays. In this scheme, the duration of delays in the transmitter and receiver is determined not by the duration of the bit, but by the decay time of the autocorrelation function of the chaotic signal. Purpose of this work is to experimentally demonstrate the possibility of physical implementation of a direct-chaotic differentially coherent information transmission scheme in a wired communication channel. Methods. For this, a layout of the communication scheme, transmitting a binary data stream in the frequency range from 200 to 500 MHz, was designed and assembled. The layout is an ultrawideband differentially coherent transmitter and receiver connected via a wired channel. Results of the experiment are in full agreement with the previously obtained results of the analytical evaluations, as well as with the data of computer simulation. Conclusion. In the course of the research, a transceiver layout of a differentially coherent ultra-wideband direct chaotic communication scheme was developed, designed and manufactured. For the first time, experiments on the transmission of digital information were carried out on it, and thereby the practical feasibility and operability of the proposed direct chaotic differentially coherent transmission scheme were proved.

Performance Limit of Gate-All-Around Si Nanowire Field-Effect Transistors: An Ab Initio Quantum Transport Simulation

The gate-all-around (GAA) $\mathrm{Si}$ nanowire (NW) field-effect transistor (FET) is considered one of the most promising successors of the current mainstream $\mathrm{Si}$ fin FET (FinFET) owing to its better electrostatic gate control. Experimentally, the diameter of $\mathrm{Si}$ NWs has been scaled down to 1 nm. In this paper, the performance limit of the GAA $\mathrm{Si}$ NWFET with a 1-nm diameter is investigated by utilizing ab initio quantum transport simulations. We prove that the electrical conduction is concentrated in the core of the ultranarrow wire channel. The minimum gate length (${L}_{g}$) at which the n- and p-type GAA $\mathrm{Si}$ NWFET can satisfy the high-performance application requirements (on-state current, gate capacitance, delay time, and power dissipation) of the International Technology Roadmap for Semiconductors is 3 nm. The best-performing 5-nm-${L}_{g}$ n-type GAA $\mathrm{Si}$ NWFET exhibits an energy-delay product comparable with typical monolayer two-dimensional FETs. Compared with the similar-sized trigate $\mathrm{Si}$ NW FinFET, an approximately 200% increase in the on-state current and about 15% decrease in the subthreshold swing are witnessed in GAA $\mathrm{Si}$ NWFET at the same 5-nm ${L}_{g}$. Through strain engineering, about an 80% increase of on-state current is observed in the 5-nm-${L}_{g}$ p-type GAA $\mathrm{Si}$ NWFET. Our research demonstrates the vast potential of the GAA $\mathrm{Si}$ NWFET in the sub-3-nm gate-length region.

Various transmission codes for the control of bit error rate in both optical wired and wireless communication channels

Abstract This study clarifies the data error rates optimization for OFC/OWC channels based on different transmission codes. These codes that are namely multi bits/symbol digital pulse interval modulation (DPIM), multi bits/symbol pulse position modulation (PPM), nonreturn to zero inverted (NRZI), 4 bit data symbol/5 bit code (4B5B), and Manchester for upgrading optical wired/wireless communication systems. The optical power through OFC/OWC channels, S/N ratio, the output power at the receiver side are stimulated with high bit transmission rates. The effects of coding complexity on the Q-factor, BER, optical power, and electrical received power are also stimulated using both DPIM and PPM coding.

Insights from the Experimentation of Named Data Networks in Mobile Wireless Environments

The Information-Centric Network (ICN) paradigm has been touted as one of the candidates for the Internet of the future, where the Named Data Network (NDN) architecture is the one leading the way. Despite the large amount of works published in the literature targeting new implementations of such architecture, covering different network topologies and use cases, there are few NDN implementations in real networks. Moreover, most of these real-world NDN implementations, especially those addressing wireless and wired communication channels, are at a small scale, in laboratory environments. In this work, we evaluate the performance of an NDN-based implementation in a mobile wireless network, as part of a smart city infrastructure, making use of multiple wireless interfaces. We start by showing how we have implemented the NDN stack in current network nodes of the smart city infrastructure, following a hybrid solution where both TCP/IP and NDN paradigms can coexist. The implementation is evaluated in three scenarios, targeting different situations: mobility, the simultaneous use of different wireless interfaces and the network characteristics. The results show that our implementation works properly and insights about the correct NDN parameterization are derived.

Modeling Self-Assembly of Polymer-Based Wired Nano-Communication Channel

Modeling Self-Assembly of Polymer-Based Wired Nano-Communication Channel

A Comparative Study of Speech Coding Techniques for Electro Larynx Speech Production

Speech coding is a method of earning a tight speech signals representation for efficient storage and efficient transmission over band limited wired or wireless channels. This is usually achieved with acceptable representation and least number of bits without depletion in the perceptual quality. A number of speech coding methods already developed and various speech coding algorithms for speech analysis and synthesis are used. This paper deals with the comparison of selected coding methods for speech signal produced by Electro Larynx (EL) device. The latter is a device used by cancer patients with their vocal laryngeal cords being removed. The used methods are Residual-Excited Linear Prediction (RELP), Code Excited Linear Prediction (CELP), Algebraic Code Excited Linear Predictive (ACELP), Phase Vocoders based on Wavelet Transform (PVWT), Channel Vocoders based on Wavelet Transform (CVWT), and Phase vocoder based on Dual-Tree Rational-Dilation Complex Wavelet Transform (PVDT-RADWT). The aim here is to select the best coding approach based on the quality of the reproduced speech. The signal used in the test is speech signal recorded either directly by normal persons or else produced by EL device. The performance of each method is evaluated using both objective and subjective listening tests. The results indicate that PVWT and ACELP coders perform better than other methods having about 40 dB SNR and 3 PESQ score for EL speech and 75 dB with 3.5 PESQ score for normal speech, respectively.

Enhancing Absorption Performance of CO2 by Amine Solution through the Spiral Wired Channel in Concentric Circular Membrane Contactors.

The CO2 absorption rate by using a Monoethanolamide (MEA) solution through the spiral wired channel in concentric circular membrane contactors under both concurrent-flow and countercurrent-flow operations was investigated experimentally and theoretically. The one-dimensional mathematical modeling equation developed for predicting the absorption rate and concentration distributions was solved numerically using the fourth Runge–Kutta method under various absorbent flow rate, CO2 feed flow rate and inlet CO2 concentration in the gas feed. An economical viewpoint of the spiral wired module was examined by assessing both absorption flux improvement and power consumption increment. Meanwhile, the correlated average Sherwood number to predict the mass-transfer coefficient of the CO2 absorption mechanisms in a concentric circular membrane contactor with the spiral wired annulus channel is also obtained in a generalized and simplified expression. The theoretical predictions of absorption flux improvement were validated by experimental results in good agreements. The amine solution flowing through the annulus of a concentric circular tube, which was inserted in a tight-fitting spiral wire in a small annular spacing, could enhance the CO2 absorption flux improvement due to reduction of the concentration polarization effect. A larger concentration polarization coefficient (CPC) was achieved in the countercurrent-flow operations than that in concurrent-flow operations for various operations conditions and spiral-wire pitches. The absorption flux improvement for inserting spiral wire in the concentric circular module could provide the maximum relative increment up to 46.45%.

On the assessment of the reliability of the train radio communication channel

The research purposeis to develop an approach to assessing the reliability of a train radio communication channel based on the representation of a radio communication network in the form of a model that includes both traditional elements (various types of equipment, a wire channel) and a radio channel, which is proposed to be described by the availability of radio coverage, which varies depending on the location of the mobile subscriber. In the research methods of the theory of reliability, and, in particular, the assessment of the availability factor of the elements of the radio communication system and communication channels, dynamically changing during the movement of the mobile radio station. In addition, to assess the energy of radio channels, the theory of radio wave propagation was applied, including on the basis of industry recommendations for calculating radio communication networks of JSC Russian Railways. As result of the research, a method was proposed for assessing the dependence of the reliability of a train radio communication channel (in terms of readiness) on the track coordinate. In this case, the radio communication channel dynamically changes the composition of the elements when the mobile subscriber moves along the railway section. Simultaneously, for each point of the section, the calculation formula is also dynamically changed, which makes it possible to find the value of the readiness of the communication channel. The proposed approach allows to identify the sections of technological radio communication networks that are weakest from the point of view of communication reliability and take this information into account when planning work to improve the reliability of communication networks.

Multifuctional Janus Materials for Rapid One-Way Water Transportation and Fog Collection.

A novel micronano wire channels Janus membrane (WCJM) was fabricated by a convenience spraying method. We prepared a series of samples with different (super)hydrophobic energy barriers and studied the effects of WCJMs on one-way transportation and fog collection. The droplets can be one-way transported from the (super)hydrophobic side to the superhydrophilic side, forming a transport channel when they contact the superhydrophilic micronano wire under hydrostatic pressure. In the experiment, when droplets touch the exposed micronano wires, they will be rapidly absorbed by the superhydrophilic side. However, when the superhydrophobic energy barrier is thick and the superhydrophobic layer completely covers the micronano wires on the substrate surface, the droplets cannot achieve one way transport behavior. Besides, we observed three different fog collection modes. They have a significant difference in fog collection efficiency. In WCJM-3, the superhydrophobic side collects fog in a dropwise condensation mode, and then transported to the superhydrophilic side through the micronano wire channels for storage, with the highest fog collection efficiency (1.1 g/cm2·h). The results show that the WCJM surface not only makes full use of the difference in wettability and micronano wire structure to promote the droplets one-way transportation, but also improves the fog collection performance by accelerating surface regeneration, which has potential application value in fog collection, droplet treatment and related engineering.

Оцінювання надійності провідного керуючого каналу із трикратним резервуванням для спільної, роздільної та комбінованої кабельних оболонок

Aim. To develop an approach for quantifying the reliability of the wired tripled control channel with common, mixed, and separate cable jackets. Method. Reliability is formalized using block diagrams and dynamic fault trees. Static and dynamic models have been developed to evaluate the reliability indicators of the wired control channel with triple redundancy. The basis for obtaining these models is the state and transitions diagram. Static models are formed using logical-probabilistic expressions. Dynamic models are based on the principles of Markov analysis. Results. For the core failure intensity, which is higher than the intensity of the cable jacket failure, it is shown that a separate cable jacket provides the highest reliability, and a common cable jacket provides the lowest. Accordingly, the mixed cable jacket in terms of reliability occupies an intermediate position with a slight approximation to the separate. Reliability indicators calculated from static models are understated in all three cases compared to those calculated from dynamic models. Although static models give less accuracy, they do not require the structure of sophisticated Markov models. Scientific novelty. The approach for modeling the reliability of control channels with triple core redundancy for cases of separate, mixed and common cable jackets has been improved. Practical significance. The proposed approach is recommended to be used to assess the reliability during the equipment design, the operation of which may endanger the life and health of service personnel. The obtained results are a mathematical basis for studying the reliability of a wired cable channel with three cores, which are protected by reinforcement and cable jacket in different combinations.

Improving the functioning efficiency of 6-10 kV electrical networks with isolated neutral in conditions of single-phase ground faults

The main objectives of this publication are: 1) to attract the attention of energy specialists to the problems of reliability and electrical safety of 6-10 kV overhead electrical networks with isolated neutral, operating in conditions of single-phase insulation damage; 2) substantiation of the feasibility of introducing a fundamentally new way to improve the efficiency of 6-10 kV distribution networks, based on the resonanceless limitation of the single-phase ground fault current arising from the breakdown of the insulator and the use of its own infrastructure of the electrical network for remote identification of the place of its occurrence. The expediency of including a nonlinear surge suppressor between the traverse and the grounding outlet of the reinforced concrete support is confirmed by the positive results of experimental studies carried out on the basis of high-voltage testing laboratories of IDGC of Center PJSC - Orelenergo and EnerGarant LLC. The use of deductive analysis allowed the authors to select a reliable and affordable electrical insulating material installed between the support and the traverse, as well as to formulate the main requirements for it, including taking into account weather and climatic factors. The analysis of various methods of transmitting information about the place of occurrence of the insulator damage made it possible to establish the predominant advantage of a wired communication channel using its own 6-10 kV electric network infrastructure. The authors have developed an original circuitry solution that provides remote identification of the insulator damage location using a thyristor shunting the nonlinear surge suppressor, according to a given switching algorithm, and also provides local identification of the insulator breakdown by means of special signaling devices with volatile power supply. It is expected that the proposed method, with relatively low investment, will significantly reduce the level of accidents and electrical hazards in overhead distribution networks of 6-10 kV, as well as minimize the costs associated with their operation and undersupply of electrical energy.

Simulation and assessment of battery depletion attacks on unmanned aerial vehicles for crisis management infrastructures

The article discusses the problem of simulation and assessment of battery depletion attacks on unmanned aerial vehicles (UAVs) in crisis management systems. These devices operate in security sensitive infrastructures, thus, they are subject to accidental incidents or intentional ones performed by an attacker, such as natural disasters, terrorist attacks or sabotage accidents. The drones are particularly subject to battery depletion attacks, which exploit their autonomy, their physical movements in space, their wire and wireless communication channels, or even all together. The article classifies, first, various battery depletion attacks on an UAV and presents their analysis. Next, we describe how we adapted a Parrot AR.Drone 2.0 to the needs of a crisis management scenario by adding specific hardware control and monitoring units as well as made empirical studies on it. Simulation and experiments allowed us to confirm the feasibility of such attacks in practice, evaluate and compare their effect.

Topological quantum switch and controllable one-dimensional conducting paths in antimonene facilitated by breaking the inversion symmetry

Based on the recently found non-trivial topology of buckled antimonene, we propose the conceptual design of a quantized switch that is protected by topology and a mechanism to create configurable 1D wire channels. We show that the topologically required edge states in this system can be turned on and off by breaking the inversion symmetry (reducing the symmetry from $S_6$ to $C_3$), which can be achieved by gating the system. This is shown to create a field-effect quantum switch projected by topology. Secondly we show that by locally gating the system with different polarity in different areas, a soliton-like domain wall is created at their interface, which hosts a protected electronic state, in which transport could be accessed by gated doping.

Review of Duodenoscope Infection Prevention Practices at the Medical University of South Carolina.

A rise in duodenoscope-associated infections, especially in regard to multidrug-resistant organisms, has led to an increase in scrutiny regarding duodenoscope reprocessing. Endoscopic retrograde cholangiopancreatography scopes have a specialized elevator wire channel, allowing more flexible duct cannulation; however, this channel can be difficult to reprocess with standard techniques. Although strict adherence to manufacturer reprocessing protocols remains the primary means of infection prevention, periodic microbiological surveillance is a Food and Drug Administration-recommended practice that the Medical University of South Carolina has implemented to further prevent duodenoscope-associated infections. The Medical University of South Carolina obtains 2 separate cultures from 2 duodenoscopes every 2 months, which undergo standard speciation and sensitivity and are returned to use once negative at 48 hours. The initial results of the Medical University of South Carolina's surveillance cultures are negative for any multidrug-resistant organisms; however, other centers should consider implementing surveillance cultures into their reprocessing practices and closely monitoring for future endoscope infection prevention modalities.

The “two-cut monorail” technique, for the over-the-wire removal of the Impella CP device

The Impella is a percutaneously placed intra-arterial flow pump positioned across the aortic valve for circulatory support. A limitation of the Impella is that it lacks a central wire channel, to maintain intra-arterial wire access when removing the device. Open surgical arterial cutdown is needed for the removal of the Impella CP placed emergently, without the use of preclose sutures. This case review describes an alternative removal method for the aforementioned occasions.

Effectiveness of a Matched Filter to Cope With Harsh Phase and Amplitude Modulated EMI

This article investigates the effectiveness of a matched filter to cope with continuous wave electromagnetic disturbances that are phase and amplitude modulated from wireless systems, e.g., binary phase shift keying and quadrature amplitude modulation. A wired communication channel between sender and receiver that uses nonreturn-to-zero-level data encoding is disturbed by those nearby wireless systems. A matched filter is used on the wired communication channel to filter out the additional unwanted wireless disturbance. The bit-error rate (BER) is calculated after filtering and decoding the received voltages and is used as a metric to compare different kinds of disturbances and different levels of sampling frequency. The results show that the matched filter is very effective when the carrier frequency of the disturbance is equal to an integer multiple of the bit frequency and when not equal to the sampling frequency. This sampling frequency is determined by the bit rate of the desired signal and the oversampling factor on which the matched filter is based. Finally, the filter gain at a BER of 0.1% is determined. This gain shows that an oversampling of 4 times per bit and using a matched filter already results in an average filter gain of 10–15 dB.