Impedance Matching Device Research Articles

The novel impedance matching device realized by the structure of air-gap ring based on the doping method at microwave frequency

The doping method enabled the epsilon-near-zero (ENZ) medium to adjust its permeability effectively. In this study, we theoretically analyze that the gap ring structure formed by the ENZ medium doped with perfect electrical conductor (PEC) can be equivalent to the controllable series reactance. Based on this concept, a universal matching network that can match any complex impedance load by adjusting the gap ring spacing is constructed. We used the above universal matching network to carry out theoretical and simulation calculations on the matching effect of a random-sized stepped waveguide and horn antenna, and the results show that the impedance-matching technology has a good matching effect for different loads. Finally, experimental verification is carried out. Compared with traditional impedance-matching networks, the proposed structure has the characteristics of simplicity, reliability, low loss, high carrying power, low preparation requirements, and good application prospects. This work is a good example of the practicality of ENZ media and also provides a very meaningful idea for the development of new electromagnetic matching devices.

Electromechanical ice protection system: de-icing capability prediction considering impedance matching effect

Abstract Due to the safety threats caused by icing, the de-icing system is essential in the aviation industry. As an effective method, the electromechanical de-icing system (EDS) is a new ice-protection system based on mechanical vibration principles. For the majority of the current research on system de-icing capability estimation, the effect of impedance-matching is not considered. Impedance matching plays a very important role in improving the performance of the electromechanical system, so we must also consider the impact of impedance matching when designing the EDS. In the present study, a de-icing capability prediction method considering the impact of an impedance-matching device is established based on experimental and numerical methods. The results indicate that the impedance-matching effect has no impact on the mechanical vibration of the structure for the same load power. Meanwhile, impedance-matching devices can significantly improve the power factor and increase the interface shear stress/strain for de-icing. Eight different vibrational modes were tested, and the experimental results showed that the actual interface shear strain after impedance matching is inversely proportional to the de-icing time. The verification experiments were conducted and the accuracy of the proposed prediction method was verified.

Design of an optimized load-resilient conjugate T for the ICRH system in the LHD using a novel hybrid circuit/3DLHDAP code and experimental results

It is crucial to correctly predict the S-matrix with plasma and set the optimal impedance matching device in the ion cyclotron resonance heating (ICRH) antenna system design. In this paper, a hybrid circuit/3DLHDAP code to verify the S-matrix measurements in the presence of plasma and optimize the load-resilient conjugate-T circuit for Large Helical Device (LHD) ICRH antennas has been developed and benchmarked. The variation of S-matrices for handshake form (HAS) and field-aligned-impedance-transforming (FAIT) antenna systems with density, magnetic field and coupling distance during heating obtained by the code’s simulations agrees with that of with the LHD ICRH experiments. The mutual coupling of toroidally aligned HAS antennas is larger than that of poloidally aligned FAIT antennas over a wide range of densities. When the density and coupling distance increase, under a magnetic field on the magnetic axis of 2.75 T and 1.0 T, within a certain density change range, at the minimum voltage position with vacuum injection, the change rule of the antennas’ Sa_minV_ 11 and Sa_minV_ 22 with density is opposite to that with coupling distance, which means that under certain conditions, adjusting the coupling distance may make up for the S-parameters changes caused by plasma density variation, keeping the minimum voltage position fixed, and may make impedance matching easier to achieve during long-pulse operation. Based on obtaining the S parameters, conjugate-T circuits for the HAS and FAIT antennas are designed with the hybrid circuit/3DLHDAP code, which can keep the reflection coefficients low without controlling impedance matching device over a wide range of plasma parameters region. The related results in this paper may provide some guidance for the high-power long-pulse operation of the ICRH antenna system on the fusion device.

Dual-Band Impedance Matching Using Folded Stubs Composed Of Periodic Structures

Impedance matching devices are essential elements in telecommunication systems. They avoid the reflection of the electromagnetic waves and promote the maximum power transference among circuits with different electric impedances. In dual-band telecommunication systems, new impedance matching techniques have been developed. In this article, the use of folded stubs composed of periodic structure is investigated. This methodology uses two stubs, one for each frequency bands. The isolation between them is achieved by the prohibited electromagnetic bands and the use of folds in the conductive strip, which form the periodic structures, allows reducing the dimensions of the device.

Design of Coaxial TGV Substrates; Enhancing RF Via to Via Isolation

ABSTRACT Enhanced electronic substrate design objectives for higher frequency products (5G telecom systems) can now be achieved with the use of novel coaxial-thru-via configurations in glass (TGVs). When compared with standard pillar filled thru-vias in glass, coaxial-thru-vias exhibit greater than 40dB improvement in via-to-via crosstalk isolation and 0.5dB improvement in insertion loss both at 30 GHz. Coaxial-Thru-Vias provide precise unadjusted 50 Ohm impedance matching device designs at the 5G product frequencies. The coaxial dielectric core chemistry is modifiable to tune electrical parameters to meet specific design requirements. This paper summarizes all designs, simulations, and modeling performed to date. The superior properties of coaxial vias in glass and fused silica over standard pillar vias are documented and captured in sweeps to 100 GHz. Via and pitch dimensions of 100/200 and 50/100 um have been assessed. Manufacturing methods have been demonstrated using thick film conductor materials in prototype designs. Coaxial vias can optionally be fabricated as dual-purpose configurations reducing thru-via count requirements, substrate footprints, and package/module costs.

Implementation of vibration signals receiving unit on Raspberry single-board computers

The paper dedicated to vibration measurement system development on the Raspberry Pi basis. Main features of the solution are low-cost, easy access to components and functionality and flexibility provided by Raspberry Pi usage. Circuit solution and configuring procedures are presented and described. In particular, block diagram of the vibration measurement system with piezo-electric sensors. Two variants of the vibration measurement system, on the Raspberry Pi B+ and Raspberry Pi 3B correspondingly, were implemented and tested as well. In addition, two variants of impedance-matching device were implemented. Conducted and described experiments confirm performance both separate components and the whole solution. Presented results are applicable for correlation leak detectors new algorithmic solutions and in educational process.

A dynamic impedance matching algorithm of three-stub tuners based on equivalent circuit analysis

Three-stub waveguides are common impedance matching devices which are essential for a wide range of high-power microwave applications. Based on equivalent circuit analysis method, this article presents a novel matching algorithm which can be applied for three-stub tuners to implement continuous, automatic and real-time impedance matching. Equivalent model of a stub waveguide is firstly established by using transmission lines in series and capacitors in parallel. Then, according to the proposed model, the mathematical expression of reflection coefficient at different stub depth is derived by using currently detected reflection coefficient and stub depth. Later, based on the derived expression, an algorithm is developed to determine the optimum insertion depths of the stubs when VSWR is minimum. The S 11 parameters of the stub waveguide which are calculated by the method agree well with those measured by vector network analyser. Meanwhile, the algorithm is able to limit reflection coefficient under –10 dB and can easily be redesigned for waveguides of different sizes. Thus, it shows a promising future in industrial impedance matching applications.

Bioinspired metagel with broadband tunable impedance matching.

To maximize energy transmission from a source through a media, the concept of impedance matching has been established in electrical, acoustic, and optical engineering. However, existing design of acoustic impedance matching, which extends exactly by a quarter wavelength, sets a fundamental limit of narrowband transmission. Here, we report a previously unknown class of bioinspired metagel impedance transformers to overcome this limit. The transformer embeds a two-dimensional metamaterial matrix of steel cylinders into hydrogel. Using experimental data of the biosonar from the Indo-Pacific humpback dolphin, we demonstrate through theoretical analysis that broadband transmission is achieved when the bioinspired acoustic impedance function is introduced. Furthermore, we experimentally show that the metagel device offers efficient implementation in broadband underwater ultrasound detection with the benefit of being soft and tunable. The bioinspired two-dimensional metagel breaks the length-wavelength dependence, which paves a previously unexplored way for designing next-generation broadband impedance matching devices in diverse wave engineering.

Uncovering the secreted signals and transcription factors regulating the development of mammalian middle ear ossicles

The mammalian middle ear comprises a chain of ossicles, the malleus, incus, and stapes that act as an impedance matching device during the transmission of sound from the tympanic membrane to the inner ear. These ossicles are derived from cranial neural crest cells that undergo endochondral ossification and subsequently differentiate into their final functional forms. Defects that occur during middle ear development can result in conductive hearing loss. In this review, we summarize studies describing the crucial roles played by signaling molecules such as sonic hedgehog, bone morphogenetic proteins, fibroblast growth factors, notch ligands, and chemokines during the differentiation of neural crest into the middle ear ossicles. In addition to these cell-extrinsic signals, we also discuss studies on the function of transcription factor genes such as Foxi3, Tbx1, Bapx1, Pou3f4, and Gsc in regulating the development and morphology of the middle ear ossicles.

A Critical Analysis of a Wireless Power Transmission (WPT) with an Improvement Method for a Non-Radiative WPT

This paper describes the analysis of the wireless power transmission including recent progresses in non-radiative wireless power transmission (WPT) and the improvement methods. Generally, WPT transmitter side consists of a DC supply voltage source, inverter/power amplifier, transmitter impedance matching device (IMD), source resonator and primary coil. The WPT receiver meanwhile consists of the secondary coil, device resonator, receiver IMD, rectifier and load. In order to achieve an efficient WPT, the WPT transmitter must transmit energy with minimum loss at the receiver side. This setup can be achieved by employing the power amplifier (PA). In this paper, the power amplifier in wireless power transmission for portable devices was designed. A Class E power amplifier was proposed and designed to improve the WPT transmitter side. The effects of zero voltage and zero derivative voltage switching on PA with optimization method was also discussed.

A Critical Analysis of a Wireless Power Transmission (WPT) with an Improvement Method for a Non-Radiative WPT

This paper describes the analysis of the wireless power transmission including recent progresses in non-radiative wireless power transmission (WPT) and the improvement methods. Generally, WPT transmitter side consists of a DC supply voltage source, inverter/power amplifier, transmitter impedance matching device (IMD), source resonator and primary coil. The WPT receiver meanwhile consists of the secondary coil, device resonator, receiver IMD, rectifier and load. In order to achieve an efficient WPT, the WPT transmitter must transmit energy with minimum loss at the receiver side. This setup can be achieved by employing the power amplifier (PA). In this paper, the power amplifier in wireless power transmission for portable devices was designed. A Class E power amplifier was proposed and designed to improve the WPT transmitter side. The effects of zero voltage and zero derivative voltage switching on PA with optimization method was also discussed.

A HOMER autotuner alkalmazása az aktív szenek mikrohullámú vizsgálata során

The author presents the microwave characteristics of active carbon, measured by the S-TEAM manufacturer HOMER Autotuner STHT V1.4 using an automatic measuring and impedance matching device for industrial microwave systems.

Advances on multi-scale MbD synthesis of WAIMs for advanced phased arrays

The most recent advances on the synthesis of wide-angle impedance matching (WAIM) devices for next-generation phased arrays are discussed. Towards this end, the WAIM design problem is formulated within the Material-by-Design (MbD) framework with the objective of minimizing the antenna input reflections caused by mutual coupling (MC) effects arising at the antenna aperture when steering the main beam in a wide angular region. Accordingly, the degrees-of-freedom (DoFs) are represented by the constituent materials of the synthesized structure and/or the micro-scale geometrical descriptors of the considered unit cells. Selected illustrative results will be shown in order to assess the effectiveness and the potentialities of leading-edge MbD solutions for the design of reliable and easy-to-implement WAIMs.

Pre-Stub Tuner for Reduction of Radio-Frequency Voltage Along Transmission Line in EAST-ICRF System

The ion cyclotron range of frequency (ICRF) heating system of the Experimental Advanced Superconducting Tokamak (EAST) is characterized by high radio-frequency (RF) power up to 12 MW and wide frequency range over 25 to 70 MHz. A high RF power transmission system composed of a liquid impedance matching device, ceramic feedthrough, decoupler, and ICRF heating antenna with four straps has been in operation for some years. In a high-power ICRF experiment, one issue that needs to be solved is the high RF voltage on the coaxial transmission line between the ICRF antenna and the impedance matching device, which is caused by low antenna loading resistance compared to the characteristic impedance of the transmission line. A stub tuner is employed to reduce the RF voltage in the EAST ICRF power transmission system. Two methods to reduce RF voltage using short-circuited and open-circuited stub tuners are introduced in detail. The optimized position and length of the stub tuner are analyzed and calculated to achieve a smaller voltage reduction ratio (VRR) on the transmission line. The test with the stub tuner to reduce the RF voltage of the transmission line is carried out, and a RF VRR of ∼0.57 is achieved. The RF voltage on the transmission line is significantly reduced, and the capability of the transmission power is obviously improved. Ohmic losses caused by the surface resistance of the conductor of the coaxial transmission line are also decreased, and the probability of breakdown within the transmission line is reduced under high RF power operation.

Reviewing the Effectiveness of Contribution of Microstrip Antenna in the Communication System

The wireless communication serves the efficient information among two or more points wirelessly. Antenna is the main component in the communica-tion, which radiates and receives the radio waves or in broad way. The an-tenna also plays a role of impedance matching device, which performs the mat- ching of impedances like free-space & transmitter and receiver im-pedances at receiver end. The antennas can be categorized as Wire Antenna, Reflector Antenna, Multi-strip Antenna, Aperture Antenna, Lens Antenna, and Array Antenna. In this paper, the Multi-strip Antenna fundamentals are discussed with its categorization. In this paper various aspects of the Multi-strip antenna are discussed along with the existing researches in it. A research gap is formulated based on the research survey and presents a future scope of research. The existing research gap in Multi-strip Antenna is formulated along with the future line of research in order to overcome the existing research gap.

Mechanical Impedance Matching Using a Magnetic Linear Gear

As part of the Fp7 Clean Sky Project, a linear magnetic gear prototype, called Z-transmitter, for aerospace application was designed, built, and tested. It demonstrates a maximum force capacity of 4700 N at 25°C and 4500 N at 90°C. Force ratio between slow and fast stages remains constant and equal to the design value: 7.0. The behavior of the real Z-transmitter as a mechanical impedance matching device when any stiffness is attached to the fast stage including the limit cases of a blocked fast stage or a free to move fast stage is experimentally explored. Although the real Z-transmitter deviates from the ideal, frictionless and massless, device, it still provides an impedance matching effect large enough to potentially become an extremely useful technology for vibration control when combined with other elements such as dampers, springs, or active elements.

An Appraisal of Matching Devices for Measurements of Asymmetrical Industrial Radio Interference

The justification for using a TK11 probe as an impedance matching device for measurements of asymmetrical industrial radio interference, for the purpose of supplies in the 0.15–30 MHz frequency band with a current strength of less than 25 A, is investigated. The conditions under which it is possible to use this probe for regulated measurements are determined.

A 130 nm wideband fully differential linear low noise amplifier

In this paper, a wide-band fully differential linear low noise amplifier (LNA) in a standard 130nm CMOS process is presented. The LNA utilizes Active Post Distortion (APD) as a voltage combiner that prepares a linear transconductance for enabling harmonic cancellation, which can also mitigate the impedance matching device noise. The impedance matching device is connected to the output transistors to ensure the harmonic cancellation at output node while preserving NF and input return loss at input node. This harmonic cancelation is also APD that guarantees an IIP2 and IIP3 of about 26dBm and 4dBm respectively at output node. Operating in a wide bandwidth of about 1.5GHz from 3.5 to 5GHz, the LNA obtains a maximum power gain (S21) of about 14dB, input reverse isolation (S11) and NF of less than -15dB and 3.9dB respectively. From a 1V power supply it dissipates about 21mW and occupies 0.557×0.567mm2 of chip area.

Field-aligned-impedance-transforming ICRF antenna in the LHD

Newly developed ion cyclotron range of frequencies (ICRF) antennas were fabricated and installed in the Large Helical Device (LHD). The antennas, called field-aligned-impedance-transforming (FAIT) antennas, were designed based on former handshake form (HAS) antennas for high power and steady-state operation. The FAIT antennas demonstrated higher loading resistance and lower temperature on ceramic feed-through than HAS antennas. Antenna impedance and injected power were measured precisely using a directional coupler installed between the impedance matching device and antenna. It was shown that an injection power of 1.8MW or a power density of 15MW/m2 would be possible for short-pulse discharges. The mutual coupling between two FAIT antennas is small enough, since any current phase is possible without adjusting the impedance matching device. Although the FAIT antennas are aligned in a poloidal direction, a high heating efficiency of 85% was achieved with the proper minority concentration ratio.

Coupling Enhancement of Waveguide fed Dielectric Resonator Antenna using Tapered Section of Waveguide

A novel technique for coupling enhancement of waveguide fed hemispherical dielectric resonator antenna (DRA) is proposed in this paper. A tapered section of waveguide is inserted between the rectangular waveguide and the ground plane to improve coupling. The tapered section acts as an impedance matching device that increases the coupling from waveguide to DRA. The proposed structure has been simulated using Ansoft HFSS and compared the results with CST Microwave Studio. The effect of various design parameters of the antenna on return loss characteristics is studied.