Signal Wires Research Articles

A novel coplanar waveguide resonator on flexible substrate

In this paper a flexible coplanar waveguide resonator with high quality factor is proposed and fabricated. The device consists of a compact coplanar waveguide (CPW) and two complementary split rectangle resonators (CSRR) locating between the central signal wire and the ground plane of the CPW. The designed and measured values of frequency, attenuation, and quality factor of the resonant dips are 31.9GHz and 31.8GHz, −45dB and −12dB, and 115.7 and 35.1, respectively. The differences between the simulated and measured values of attenuation and quality factor are due to the imperfectmetal structure. The frequency of the resonant dip is very sensitive to dielectric environment. This chip device is very promising for biomedical and sensing applications.

Experimental Results of Simplified Balance Bridges for the KSTAR Quench Detection System

The primary quench detection system of the Korea Superconducting Tokamak Advanced Research (KSTAR) device has been operated in technical and plasma experiments for eight years. Cowound-type quench detectors have exhibited distinct performance of compensation for both self-induction and mutual induction; on the other hand, some cowound strips tended to break in the long-term operation. In contrast, Wheatstone bridge (WB)-type quench detectors had no wire breakage, and their signal wires are still accessible and repairable. Therefore, WB-type quench detectors are very important to be a backup method of quench detection for the coils. New WBs using a half-bridge at a fixed ratio of resistances of 1:1 were tested in the KSTAR operation. Upper-lower comparison of the new WBs performed good compensation for induced voltage. The new WBs clearly demonstrated that the bridge circuits may become very simple, and in situ calibration may be unnecessary if the arrangement of voltage taps and quench detectors is optimized with respect to the magnetic field of the tokamak device.

Multiplex transmission system for gate drive signals of inverter circuit using surface acoustic wave filters

We propose and fabricate a multiplexed transmission system based on frequency-division multiple access (FDMA) with surface acoustic wave (SAW) filters. SAW filters are suitable for use in wide-gap switching devices and multilevel inverters because of their capability to operate at high temperatures, good electrical isolation, low cost, and high reliability. Our proposed system reduces the number of electrical signal wires needed to control each switching device and eliminates the need for isolation circuits, simplifying the transmission system and gate drive circuits. We successfully controlled two switching devices with a single coaxial line and confirmed the operation of a single-phase half-bridge inverter at a supply voltage of 100 V, and the total delay time to control the switching devices was less than 2.5 µs. Our experimental results validated our proposed system.

Fundamental Research on Control Method for Power Conversion Circuit of Wireless In‐Wheel Motor Using Magnetic Resonance Coupling

SUMMARYThe in‐wheel motor (IWM) is the most preferred driving mechanism of electric vehicles for its advantages of vehicle motion control, energy efficiency, and vehicle design flexibility. One of the technical problems of the IWM is the reliability of power and the signal wires. Wireless power transfer technology is the best solution to this problem. In this paper, a bidirectional wireless power transfer circuit using a primary inverter and a secondary converter is proposed. We propose a control method for both the inverter and the converter to stabilize the secondary dc‐link voltage. The proposed method is verified by simulation and experiment using simulated test equipment.

Real-time monitoring instrument designed for the deformation and sliding period of colluvial landslides

A real-time monitoring instrument for colluvial landslides that can capture horizontal displacement during the deformation period of the slope, deep dislocation displacement, accurate depth of the slip surface, and sliding direction during the initial sliding period has been developed. The horizontal displacement monitoring system is a monitoring apparatus assembled in an array based on the MEMS (Micro-Electro-Mechanical System). Horizontal displacement is obtained by integration of the X- and Y-direction angles along the drilling direction, and the sliding direction is simultaneously measured via vector composition of the X- and Y-direction angles obtained from the MEMS sensor. Deep dislocation displacement is calculated based on the relative displacement between the base point embedded in the bedrock and measuring point above the sliding surface, and measurement of relative displacement is executed by an angular displacement sensor fixed on top of the inclinometer tube. The accurate depth measurement of the slip surface is transferred to the judgment about the on-off state of the signal wire. Based on the long-term monitoring of the Yu Jiaba landslide at the Three George dams, an open-pit mine in Inner Mongolia province, and an Anshan open-pit mine, the results reveal that the reliability of the instrument is very high. High accuracy, ability to capture the entire landslide process, large deformation monitoring, autonomous data collection, and reusable characteristics could be implemented.

Processing and Interpretation of Crack-Propagation Sensors


 
 
 The goal of gearbox prognostics, once a failure has been detected, is to estimate the degree of damage. Development of probabilistic damage assessment requires high quality ground truth. The present report describes practical analysis, processing, and interpretation of signals from crack-propagation sensors and damage estimation during gear teeth crack propagation. The study considers two types of crack propagations: one for a fatigue-tester-based crack propagation, and the other for a propagation in a gearbox. Crack closing occurs in both types of crack propagation and must be accounted for in assessing the damage. The analysis is conducted for sensors connected as a voltage divider. Signal conditioning and wire breakage inference are examined in detail. In addition, we discuss how equipping each gear tooth with two crack- propagation sensors, one on each gear face, can provide a better damage estimation.
 
 

Front-end electronics and data acquisition system for a multi-wire 3D gas tracker

This paper presents the design and implementation of the front-end electronics and the data acquisition (DAQ) system for readout of multi-wire drift chambers (MWDC). Apart of the conventional drift time measurement the system delivers the hit position along the wire utilizing the charge division technique. The system consists of preamplifiers, and analog and digital boards sending data to a back-end computer via an Ethernet interface. The data logging software formats the received data and enables an easy access to the data analysis software. The use of specially designed preamplifiers and peak detectors allows the charge-division readout of the low resistance signal wire. The implication of the charge-division circuitry onto the drift time measurement was studied and the overall performance of the electronic system was evaluated in dedicated off-line tests.

Measurement-Based Modeling and Worst-Case Estimation of Crosstalk Inside an Aircraft Cable Connector

Crosstalk within cable bundles can degrade system performance. In aircraft systems that use shielded twisted pairs, the crosstalk occurs primarily in the connector where individual signal wires are not shielded or twisted. In many cases, the parameters which determine crosstalk within the connector are unknown because the connector is closed and wires cannot be easily accessed. Expanding on prior research [14] , a methodology for measuring coupling parameters and modeling crosstalk within aircraft cable connectors at low frequencies (<400 MHz) was developed. The values of mutual inductance and capacitance were extracted from measurements made with a vector network analyzer (VNA). The characteristics of the individual wires were extracted from VNA-measured TDR response. The accuracy of the model was evaluated through comparison of simulated and measured results. Additionally, a closed-form solution was developed to estimate the worst-case envelope of the differential crosstalk. The calculated results match the measured peak values well. This worst-case crosstalk estimate allows effective evaluation of the impact of crosstalk within different connectors. The developed method can be effective for analyzing complex aircraft cable assemblies and connectors without requiring extensive knowledge of the assembly procedure.

Quench Detection Method for HTS Coils Using Electromagnetically Coupled Coils

Generally, in order to detect the quench of the superconducting field coil for the superconducting rotating machine, signal wires for voltage taps are indispensably needed. However, the problem of the conventional method is wire twisting as the superconducting field coil rotates. Therefore, in this paper, authors suggest a new method to detect the quench of the superconducting field coil using electromagnetically coupled coils. The suggested method consists of two superconducting pancake and copper solenoid coils. Two superconducting pancake coils play roles of a field coil and external (alternating) field generation for the rotating machine. In addition, two copper solenoid coils are used to transmit the voltage wirelessly and receive the transmitted voltage using electromagnetic induction. In order to verify the feasibility of this method, experiments are performed according to the transporting current flowing through two superconducting pancake coils and separation distance between two copper solenoid coils. The result shows that it is expected to apply this method to the superconducting rotating machines for the detection of quench without direct connection of voltage taps.

磁界共振結合によるワイヤレスインホイールモータの電力変換回路の制御に関する基礎研究

The in-wheel motor (IWM) is the most preferred driving mechanism of electric vehicles for its advantages of vehicle motion control, energy efficiency, and vehicle design flexibility. One of the technical problems of the IWM is the reliability of power and the signal wires. Wireless power transfer technology is the best solution to this problem. In this paper, a bidirectional wireless power transfer circuit using a primary inverter and a secondary converter is proposed. We propose a control method for both the inverter and the converter to stabilize the secondary DC-link voltage. The proposed method is verified by simulation and experiment using simulated test equipment.

In vivo real-time 3-D intracardiac echo using PMUT arrays.

Piezoelectric micromachined ultrasound transducer (PMUT) matrix arrays were fabricated containing novel through-silicon interconnects and integrated into intracardiac catheters for in vivo real-time 3-D imaging. PMUT arrays with rectangular apertures containing 256 and 512 active elements were fabricated and operated at 5 MHz. The arrays were bulk micromachined in silicon-on-insulator substrates, and contained flexural unimorph membranes comprising the device silicon, lead zirconate titanate (PZT), and electrode layers. Through-silicon interconnects were fabricated by depositing a thin-film conformal copper layer in the bulk micromachined via under each PMUT membrane and photolithographically patterning this copper layer on the back of the substrate to facilitate contact with the individually addressable matrix array elements. Cable assemblies containing insulated 45-AWG copper wires and a termination silicon substrate were thermocompression bonded to the PMUT substrate for signal wire interconnection to the PMUT array. Side-viewing 14-Fr catheters were fabricated and introduced through the femoral vein in an adult porcine model. Real-time 3-D images were acquired from the right atrium using a prototype ultrasound scanner. Full 60° × 60° volume sectors were obtained with penetration depth of 8 to 10 cm at frame rates of 26 to 31 volumes per second.

Cable Effects Study: Tangents, Rabbit Holes, Dead Ends, and Valuable Results

Lessons learned during a study on the effects that electrical power and signal wiring harness cables introduce on the dynamic response of precision spacecraft is presented, along with the most significant results. The study was a three year effort to discover a set of practical approaches for updating well-defined dynamic models of harness-free structures where knowledge of the cable type, position, and tie-down method are known. Although cables are found on every satellite, the focus was on precision, low damping, and very flexible structures. Obstacles encountered, classified as tangents, rabbit holes, and dead ends, offer practical lessons for structural dynamics research. The paper traces the historical, experiential progression of the project, describing how the obstacles affected the project. First, methods were developed to estimate cable properties. Problems were encountered because of the flexible, highly damped nature of cables. A beam was used as a test article to validate experimentally derived cable properties and to refine the assumptions regarding boundary conditions. A spacecraft bus-like panel with cables attached was designed, and finite element models were developed and validated through experiment. Various paths were investigated at each stage before a consistent test and analysis methodology was developed.

Development of a Monitoring System for Multichannel Cables Using TDR

The purpose of this paper is to improve the management of cables that need much time and work in the measurement environment that has many multichannel cables. Therefore, a monitoring system that inspects faults and connection states of multichannel cables is suggested and designed. The system is based on time-domain reflectometry (TDR) and has two features that distinguish it from the precedent researches. One of them is a hardware interface for the multipair cable, which is a channel distributor designed using a switch. The other is the TDR-signal analysis algorithm based on the database. In other words, the system can check a number of signal wires included in a multichannel cable automatically with one step. In addition, it is able to show results of the signal analysis immediately. The performance of such a system is verified through tests. As a result, it is shown that the monitoring system is fast and reliable and it provides a reasonable analysis result on the TDR signal.

A Review of Three‐Dimensional Resistive Switching Cross‐Bar Array Memories from the Integration and Materials Property Points of View

Issues in the circuitry, integration, and material properties of the two‐dimensional (2D) and three‐dimensional (3D) crossbar array (CBA)‐type resistance switching memories are described. Two important quantitative guidelines for the memory integration are provided with respect to the required numbers of signal wires and sneak current paths. The advantage of 3D CBAs over 2D CBAs (i.e., the decrease in effect memory cell size) can be exploited only under certain limited conditions due to the increased area and layout complexity of the periphery circuits. The sneak current problem can be mitigated by the adoption of different voltage application schemes and various selection devices. These have critical correlations, however, and depend on the involved types of resistance switching memory. The problem is quantitatively dealt with using the generalized equation for the overall resistance of the parasitic current paths. Atomic layer deposition is discussed in detail as the most feasible fabrication process of 3D CBAs because it can provide the device with the necessary conformality and atomic‐level accuracy in thickness control. Other subsidiary issues related to the line resistance, maximum available current, and fabrication technologies are also reviewed. Finally, a summary and outlook on various other applications of 3D CBAs are provided.

Screen-offset printing for fine conductive patterns

Screen printing is a useful method for fabricating electrodes or signal wires of electronic devices. However, finer patterns, e.g., 50-μm-wide, are difficult to form. Herein, we introduce a newly developed printing technique called “screen-offset printing,” as a candidate method for solving this problem. In this process, first, ink patterns are screen-printed on a silicone-resin blanket; they are then transferred from the blanket to an object. In the present study, we analyze the features of screen-offset printing by observing printed conductive patterns, and elucidate the impact of this method by comparing the experimental results of screen-offset printing and conventional screen printing. In addition, we demonstrate the fabrication of fine patterns with a line and space (L/S) of 50/50 and 30/30μm.

Voltage disturbance detection method for HTS tape using electromagnetically coupled coils

This paper represents the detection method of voltage disturbance for high temperature superconducting (HTS) tape using electromagnetically coupled coils. In order to detect the voltage as the superconductor transits from the superconducting state to the normal conduction state, voltage taps are widely used to get the voltage signal. And voltage taps are connected to data acquisition device via signal wires. However this new suggested method can detect the superconducting transition voltage without signal wires between voltage taps and data acquisition device by using electromagnetically coupled coils. This system consists of two electromagnetically coupled coils, the first coil to detect and transmit the voltage of HTS tape and the second coil to pick up the transmitted voltage from the first coil. By using this new suggested method, we can build the `separated voltage-detection system`. HTS tape and first coil are located under liquid nitrogen vessel and the second coil is located under room temperature condition. In this paper, experiments are performed to verify the feasibility of the proposed method. As the result of the experiment, the separated voltage-detection system using electromagnetically coupled coils can successfully observe superconducting-normal transition of HTS tapes.

Electromigration-aware analog Router with multilayer multiport terminal structures

The combined effects of current densities and temperature in the interconnects may cause the failure of a circuit due to electromigration (EM). EM becomes increasingly more relevant with the ongoing reduction in circuit sizes caused by the evolution of nanoscale integration processes. Therefore EM effects must be taken into account in the design of both power networks and signal wires of analog or mixed-signal integrated circuits (ICs), to make their impact on the circuits’ reliability negligible. In previous EM-aware analog IC routing approaches, ‘dot-models’ are assumed for the terminals, i.e. each terminal has only one port that needs to be routed; however, in practice, analog standard cells usually contain multiple electrically-equivalent locations, often distributed over different fabrications layers, where legal connections can be made, multiport terminals, which need to be properly explored. This paper describes an EM-aware routing methodology considering multiport multiterminal signal nets of analog ICs. The complete design flow is detailed and demonstrated with experimental results and also, by generating the routing for two typical analog circuit structures for the UMC 130nm design process; the automatically generated layouts are validated using the industrial grade Calibre® tool.

A Proposal for a Novel Hybrid Interconnect Technology for the End of Roadmap

To suppress the impact of size effects on sub-20 nm wide wires, a novel aluminum-copper hybrid interconnect architecture is proposed and its potential performance has been quantified. Al wires offer lower resistivities at nanoscale dimensions because they do not need diffusion barriers, and size effects are less prominent in them due to their smaller bulk mean free path. However, their current conduction capacity is substantially lower than that of Cu wires. To get around this limitation, this letter proposes a hybrid interconnect technology to replace only short narrow local signal wires by Al wires. This scheme takes advantage of the fact that signal wires conduct bi-directional currents and are therefore virtually immune to electromigration. The improvement in chip clock frequency is predicted to be between 50% and 100% for the 7 nm technology node.

State-Dependence of On-Chip Power Distribution Network Capacitance

SUMMARY In this paper, the measurement of capacitance variation, of an on-chip power distribution network (PDN) due to the change of internal states of a CMOS logic circuit, is studied. A state-dependent PDNcapacitance model that explains measurement results will be also proposed. The model is composed of capacitance elements related to MOS transistors, signal and power supply wires, and substrate. Reflecting the changes of electrode potentials, the capacitance elements become state-dependent. The capacitive elements are then all connected in parallel between power supply and ground to form the proposed model. By using the proposed model, state-dependence of PDN-capacitances for different logic circuits are studied in detail. The change of PDN-capacitance exceeds 12% of its total capacitance in some cases, which corresponds to 6% shift of antiresonance frequency. Consideration of the state-dependence is important

Good as ‘Gold’? Portable Sleep Study Devices for Sleep-Disordered Breathing in Children

Good as ‘Gold’? Portable Sleep Study Devices for Sleep-Disordered Breathing in Children