scholarly journals Investigation of the Two-Mode Regime of Two-Gap Photonic-Crystal Resonance Systems Produced on a Printed Circuit Board with Fractal Elements "Minkowski Island

2021 ◽  
Vol 24 (5) ◽  
pp. 80-88
Author(s):  
V. A. Tsarev ◽  
A. Yu. Miroshnichenko ◽  
A. V. Gnusarev ◽  
N. A. Akafyeva
Keyword(s):  
Photonic Crystal ◽  
Printed Circuit Board ◽  
Low Voltage ◽  
Characteristic Impedance ◽  
Electronic Conductivity ◽  
Interaction Space ◽  
Circuit Board ◽  
Operational Conditions ◽  
Electronic Parameters ◽  
Strip Lines

Introduction. The development of new amplifiers and generators of the Ku- and K-bands (12…27 GHz) for use in onboard equipment is increasingly attracting research interest. Low-voltage multi-beam klystrons (LMBK) can be a promising element base for such devices. Serious problems are associated with the need to suppress parasitic modes of oscillations in NMLK operating in the centimeter and millimeter range. A possible solution is to use double-gap photonic-crystal resonators (DPCR) in LMBK. Another promising direction for improving the characteristics of such resonators is to use resonant segments of strip lines with fractal elements. In this case, the strip lines are placed on a dielectric substrate in the interaction space. Such resonators exhibit new properties that are useful for klystrons (an increase in characteristic impedance, suppression of the spectrum of unwanted frequencies, a reduction in mass and dimensions).Aim. Determination of an optimal set of electrodynamic and electronic parameters of double-gap photonic-crystal resonance systems with fractal elements "Minkowski Island" when operated as part of the LMBK resonator system, excited on π- and 2π-modes of oscillation.Materials and methods. To calculate the electrodynamic parameters of resonators, the method of finite differences in the time domain was used. The well-known Wessel-Berg method was used to calculate electronic parameters, such as the Ge / G0 electronic conductivity and the coupling coefficient M.Results. The main electrodynamic parameters of the resonator – Q-factor, resonant frequency and characteristic impedance – were investigated. The electronic parameters of the resonator, the coefficient of coupling with the electron beam, and the relative electronic conductivity for π- and 2π-modes of oscillations were calculated. In this case, three variants of the resonator with zero, first and second iterations of the fractal element were investigated. The amplitude-frequency characteristics of the resonator were investigated with a change in the pitch of the photonic crystal lattice. An estimation of the inhomogeneity of the high-frequency field in the interaction spaces of the resonator was carried out. Operational conditions were determined simultaneously for two types of oscillations without self-excitation.Conclusion. The results can find application in the development of resonator systems for klystron-type devices in the centimeter and millimeter ranges.

scholarly journals Implementation and Experimental Verification of Smart Junction Box for Low-Voltage Automotive Electronics in Electric Vehicles

2020 ◽  
Vol 10 (7) ◽  
pp. 2214
Author(s):  
Sang Wook Lee ◽  
Soo-Whang Baek
Keyword(s):  
Electric Vehicles ◽  
Printed Circuit Board ◽  
Pulse Width Modulation ◽  
Low Voltage ◽  
Short Circuit ◽  
Circuit Board ◽  
Area Network ◽  
Automotive Electronics ◽  
Overload Protection ◽  
The Impact

In this study, we designed and implemented a smart junction box (SJB) that was optimized for supplying power to low-voltage headlights (13.5 V) in electric vehicles. The design incorporated a number of automotive semiconductor devices, and components were placed in a high-density arrangement to reduce the overall size of the final design. The heat generated by the SJB was efficiently managed to mount an Intelligent Power Switch (IPS), which was used to power the headlights onto the printed circuit board (PCB) to minimize the impact on other components. The SJB was designed to provide power to the headlights via pulse width modulation to extend their lifetime. In addition, overload protection and fail/safe functions were implemented in the software to improve the stability of the system, and a controller area network (CAN) bus was provided for communications with various components in the SJB as well as with external controllers. The performance of the SJB was validated via a load operation test to assess the short circuit and overload protection functions, and the output duty cycle was evaluated across a range of input voltages to ensure proper operation. Based on our results, the power supplied to the headlights was found to be uniform and stable.

scholarly journals Design Impedance Mismatch Physical Unclonable Functions for IoT Security

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Xiaomin Zheng ◽  
Yuejun Zhang ◽  
Jiaweng Zhang ◽  
Wenqi Hu
Keyword(s):  
Transmission Line ◽  
Printed Circuit Board ◽  
Signal Transmission ◽  
Characteristic Impedance ◽  
Circuit Board ◽  
Physical Factors ◽  
Current Feedback ◽  
Impedance Mismatch ◽  
Feedback Amplifier ◽  
Current Feedback Amplifier

We propose a new design, Physical Unclonable Function (PUF) scheme, for the Internet of Things (IoT), which has been suffering from multiple-level security threats. As more and more objects interconnect on IoT networks, the identity of each thing is very important. To authenticate each object, we design an impedance mismatch PUF, which exploits random physical factors of the transmission line to generate a security unique private key. The characteristic impedance of the transmission line and signal transmission theory of the printed circuit board (PCB) are also analyzed in detail. To improve the reliability, current feedback amplifier (CFA) method is applied on the PUF. Finally, the proposed scheme is implemented and tested. The measure results show that impedance mismatch PUF provides better unpredictability and randomness.

scholarly journals Novel Low-Cost Power Divider for 5.8 GHz

Electronics ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 699
Author(s):  
Tso-Jung Chang ◽  
Krishna Pande ◽  
Heng-Tung Hsu
Keyword(s):  
Transmission Lines ◽  
Insertion Loss ◽  
Printed Circuit Board ◽  
Characteristic Impedance ◽  
Past Research ◽  
Size Reduction ◽  
Circuit Board ◽  
Superior Performance ◽  
Published Data ◽  
Coupled Line

This paper presents a new capacitive lump-free structure for power dividers using a printed-circuit board, while maintaining size reduction and physical isolation. The conventional lumped capacitors approach has self-resonant problem and cause worse S 22 and isolation at high frequencies. To overcome such technical issues, the coupled-line structures were introduced in the isolation network. After optimizing the distance between output ports and position of the isolation network, tuning the characteristic impedance and electrical length of transmission lines can decide the value of the lump resistor. The first example was designed at 1 GHz, and the resistor in the isolation network was 330 ohm, having 0.2-dB insertion loss and 19% total bandwidth, while maintaining 80-degree distance between split ports and 180-degree total length, providing 21% to 67% size reduction. The second example was designed at 5.8 GHz, which was five times greater than in past research, using an RO4003C substrate while maintaining a 0.24-dB insertion loss, 17% total bandwidth, and 0.06 dB amplitude imbalance, which was only 0.01 dB more than in recent research. Such superior performance is mainly attributed to the coupled transmission lines in the isolation network featuring a capacitive lump-free isolation network. Our data indicate that amplitude imbalance, bandwidth, and miniaturization are superior to any published data.

The Study of Characteristic Impedance of Conductive Transmission Line in FPC(Flexible Printed Circuit Board) Design and Process

2014 ◽  
Vol 1061-1062 ◽  
pp. 1021-1024
Author(s):  
Bing Li ◽  
Yi Lun Liu ◽  
Xuan Dong Zhang ◽  
Zi Jun Pan
Keyword(s):  
High Speed ◽  
Printed Circuit Board ◽  
Characteristic Impedance ◽  
Circuit Board ◽  
Strip Line ◽  
Effect Factor ◽  
Control Precision ◽  
Testing Technology ◽  
Flexible Printed Circuit ◽  
Optimal Process Parameter

To meet the demand of the signal stable at high speed, the key is control precision for the characteristic impedance of FPC. This article is intended to study the strip-line structure for reducing cross-talk (noise) and their theoretical analysis and calculation. By varying effect factor and countermeasure in the production process of FPC, and the optimal process parameter have been obtained. By using the some testing technology, the impedance of strip-line in FPC have been tested.

An autonomous untethered fast soft robotic insect driven by low-voltage dielectric elastomer actuators

2019 ◽  
Vol 4 (37) ◽  
pp. eaaz6451 ◽  
Author(s):  
Xiaobin Ji ◽  
Xinchang Liu ◽  
Vito Cacucciolo ◽  
Matthias Imboden ◽  
Yoan Civet ◽  
...  
Keyword(s):  
Power Density ◽  
Optical Sensors ◽  
Autonomous Navigation ◽  
Printed Circuit Board ◽  
Low Voltage ◽  
Dielectric Elastomer ◽  
Circuit Board ◽  
Operating Voltage ◽  
Dielectric Elastomer Actuators ◽  
Flexible Printed Circuit

Insects are a constant source of inspiration for roboticists. Their compliant bodies allow them to squeeze through small openings and be highly resilient to impacts. However, making subgram autonomous soft robots untethered and capable of responding intelligently to the environment is a long-standing challenge. One obstacle is the low power density of soft actuators, leading to small robots unable to carry their sense and control electronics and a power supply. Dielectric elastomer actuators (DEAs), a class of electrostatic electroactive polymers, allow for kilohertz operation with high power density but require typically several kilovolts to reach full strain. The mass of kilovolt supplies has limited DEA robot speed and performance. In this work, we report low-voltage stacked DEAs (LVSDEAs) with an operating voltage below 450 volts and used them to propel an insect-sized (40 millimeters long) soft untethered and autonomous legged robot. The DEAnsect body, with three LVSDEAs to drive its three legs, weighs 190 milligrams and can carry a 950-milligram payload (five times its body weight). The unloaded DEAnsect moves at 30 millimeters/second and is very robust by virtue of its compliance. The sub–500-volt operation voltage enabled us to develop 780-milligram drive electronics, including optical sensors, a microcontroller, and a battery, for two channels to output 450 volts with frequencies up to 1 kilohertz. By integrating this flexible printed circuit board with the DEAnsect, we developed a subgram robot capable of autonomous navigation, independently following printed paths. This work paves the way for new generations of resilient soft and fast untethered robots.

Study of Effects of Differential via on Signal Integrity

2013 ◽  
Vol 805-806 ◽  
pp. 1011-1016
Author(s):  
Da Long Wang ◽  
Zheng Bin Wu ◽  
Jian Wang
Keyword(s):  
Transmission Line ◽  
High Speed ◽  
Printed Circuit Board ◽  
Signal Integrity ◽  
Impedance Matching ◽  
Characteristic Impedance ◽  
Circuit Board ◽  
Printed Circuit ◽  
Differential Pair ◽  
Signal Path

If characteristic impedance along a transmission line mismatch on a printed circuit board, high-speed signal has serious signal integrity problems. When signal path of a differential pair jumps layers, mismatched impedance between differential via and differential line will affect the signal integrity. The models of a coupled transmission line and via are presented in this paper. Impedance matching of the coupled transmission line and differential via for differential signals is studied. The effects of differential via dimensions on differential signals is simulated and analyzed.

scholarly journals Investigation of the electron-wave interaction process in the two-gap photonic crystal cavities of a low-voltage two barrel x-band multi-beam klystron.

2020 ◽  
Vol 2020 (12) ◽  
Author(s):  
V.A. Tsarev ◽  
◽  
A.V. Livchina ◽  
Keyword(s):  
Photonic Crystal ◽  
Low Voltage ◽  
Power Level ◽  
Three Dimensional ◽  
Wave Interaction ◽  
Interaction Space ◽  
Output Power Level ◽  
Electromagnetic Modeling ◽  
X Band ◽  
Resonant Systems

This paper presents the results of comparing data from three-dimensional electromagnetic modeling of two designs of double-gap photonic crystal resonators of a two-barrel multi-beam klystron operating in the X-band at an accelerating voltage of 3.6 kV. These resonators are designed to operate on the main π-type oscillation with an output power level of about 2 kW. They are characterized by different profiles of the beam-let tubes. Each of the beam-let tubes in these structures contains 19 beam channels arranged in linear rows. The results of optimization of the complex of electronic and electro-dynamic parameters are presented. The optimal parameters and designs of resonant systems are found, which make it possible to significantly reduce the degree of inhomogeneity of the effective characteristic resistance in the interaction space.

scholarly journals Design and Implementation of High Directivity Directional Coupler at VHF Band Using Grounding Composed of Strip Lines Technics

2021 ◽  
Author(s):  
Atef Merghani Abdallah Abdalmagd
Keyword(s):  
Strong Coupling ◽  
High Power ◽  
Computer Aided Design ◽  
Directional Coupler ◽  
Printed Circuit Board ◽  
Circuit Board ◽  
Design System ◽  
Very High Frequency ◽  
Reflected Signal ◽  
Strip Lines

This paper proposes a design of high directivity directional coupler (D.C) based on grounding composed of strip lines for high power Radar transmitter at Very High Frequency (VHF), (150 – 200 MHz). The directional coupler is used to check and verify the transmitter output high power, frequency, and reflected signal from an antenna connected with the Radar transmitter. The performance requirements of directional couplers are a strong coupling to reduce the effect on the transmitted output power and high directivity to suppress the interference of the reflected signal from the antenna. So far, various architectures have been proposed to gain high directivity, and there have been many studies used to obtain a strong coupling and higher directivity. However, the conventional architecture of the directional coupler has a directivity of only about 20 dB, and there have been difficulties to achieve the higher directivity of more than 20 dB. In this paper, the proposed architecture of directional coupler based on grounding composed of strip lines is discussed and compares the test results of the proposed directional coupler with the conventional one. The high directivity directional coupler is designed using a computer-aided design Simulation program; Advance Design System (ADS 2016), using Rogers 4003 substrate. The directional coupler was fabricated on printed circuit board (PCB) technology and measured using a vector network analyzer (VNA). The results show that the proposed directional coupler has directivity between -25 to -24 dB inside the working bandwidth and is adequate for a high-power radar transmitter.

Reflection Phase Shift for PWB and PCBA Production Testing

2012 ◽  
Vol 9 (1) ◽  
pp. 1-9
Author(s):  
Abdelghani Renbi ◽  
Jerker Delsing
Keyword(s):  
Phase Shift ◽  
Printed Circuit Board ◽  
Low Cost ◽  
Characteristic Impedance ◽  
Process Variations ◽  
Raw Material ◽  
Circuit Board ◽  
Test Time ◽  
Board Stage ◽  
The Cost

Testing of printed wiring boards (PWBs) and printed circuit board assemblies (PCBAs) is part of electronics production that has a great impact on profitability. High throughput and low cost testing is always needed for high quality and reliability. Bare board testing, that is, testing before loading components, is crucial, and can detect such defects as opens, bridges, near-opens, near-bridges, and characteristic impedance mismatches due to process variations and compounding raw material tolerances. If not detected at the bare board stage, the cost of defects can increase 10-fold. Another motivation for an unpopulated board test is that loading expensive components on a set of defective boards could be economically catastrophic. Flying probe systems, which were developed in late 1980s, are commonly used and favorable to perform bare board isolation and continuity testing, especially when the volume is not great enough to justify bed-of-nails purchase. Flying probe system performance for a given bare board depends on the test algorithm, the mechanical speed, and the number of probes. To reduce the cost on expensive test probes and probe maintenance and to accelerate the test time, this paper presents a new and cost-efficient approach to testing both populated and unpopulated boards with open sockets, using a single probe. Specifically, a coaxial probe injects one frequency signal into the PWB trace, and the phase shift between the reflected signal from the trace and the incident wave is detected and compared with the nominal value. This nominal value is determined by testing a defect-free board that already passed direct continuity and isolation testing. By applying this test solution to bed-of-nails equipment, we reduce the amount of probes by 50%. By employing this solution to flying probe systems with two probes, for a given design with NI isolated traces and NA adjacent pairs, we reduce the number of tests from (NI + NA) tests to NI tests as isolation and continuity are performed in one go. Flying probe systems involve mechanical movements that dominate the test time. By reducing the number of mechanical movements, we will dramatically increase test throughput. The experiments demonstrate feasibility for practical use in automatic test equipment (ATE) for PWB and PCBA testing. At the highest sensitivity of the phase shift detector, the prototyped tester is capable of distinguishing between a defective and error-free board with significant margins in case of defects such as opens, DC and RF bridges, and exceeded and different width lines. The margin in the measurement between a defective and a correct board, which depends on the type of the defect, is about 7% to 68%. In the case of loaded board testing, the approach is capable of detecting opens with important margins (our test cases showed 40% and 33%), which makes it a strong candidate approach to be applied officially to PCBA testing where probing is feasible. The approach can be applied to the complete layout or to boost the test strategy where the applied test solutions do not cover 100% of the possible defects.

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