Diode Switch Research Articles

A Single-Phase Switching Diode Cascade Multistandard Inverter Based on H-Bridge

Cascaded multistandard inverter is needed in traditional high-voltage occasions, but a large number of electricitys switching devices in cascaded topology make its control complex and can lead to reduced efficiency and increased cost of inverter operation. In my text, a new basic switching diode topology proposed. It contains three switching devices, three electricity diode elements, and three DC voltage source devices with a voltage ratio of 1:1:2. In the way, five correct voltage standards can be output can be generated. Based on the combination of H-bridge topology, a new cascade topology is proposed. They increase the number of voltage standards and can work in asymmetric DC electricity supply. Therefore, different DC voltage source amplitudes can be provided, thereby reducing the number of electrical and electronic components. Compared with other most advanced cascaded topologies, The main advantage of the proposed cascade topology is the reduction where the number of electricity switche, is determined by a reasonable number of DC voltage source and the reduction in cost. At the same time, the rationality and working principle of the proposed topology are discussed, and the corresponding carrier cascade modulation method is proposed. By comparing the export voltage wave with the target waveform, the driving signal of the switch is obtained from the PWM pulse signal. The correctness and feasibility of the topology are verified by matlab2018 / Simulink simulation.

Development and Analysis of a Novel High-Gain CUK Converter Using Voltage-Multiplier Units

High conversion gain is often required for the grid integration of renewable energy resources such as PV, fuel cells, and wind. It is desired that the stress across switches is lower when higher voltage gain is attained. Similarly, it is also preferred that the converter can achieve high voltage gain without operating at higher duty cycle values. This article presents a novel high-gain CUK converter (HGCC) that uses voltage-multiplier units. The HGCC is a combination of a modified CUK converter and voltage-multiplier units (VMUs). The converter utilizes a boost converter as an input to the modified CUK converter, resulting in an increase in the gain value. The voltage gain of HGCC is increased further by placing VMUs. Based on its overall design, the HGCC inherits various advantages of the CUK converter, such as continuous input and output current, resulting in low input and output current ripples. A mathematical model is developed for the HGCC, which helps calculate its voltage gain at different stages. The model is developed considering ideal elements without conduction and switching losses. Generalized equations for output voltage and gain are derived for n level converter. A simulation study was performed in MATLAB/Simulink that further highlights the advantages of the HGCC. Voltage stresses across different components and the switching of MOSFET and diodes are studied in simulations. An experimental setup is established for hardware prototyping of the converter and validation with the simulation and Mathematical models.

Multi-band frequency reconfigurable antenna using EBG and parasitic patches

ABSTRACT This article demonstrated a compact reconfigurable microstrip antenna with a multi-band configuration. It resonates for three different frequency configurations, including the single and dual bands. The primary rectangular patch antenna resonates for WLAN (5.2 GHz center frequency) band. The reconfigurable electromagnetic bandgap (EBG) and parasitic patches near the feed line produce 4 and 6.33 GHz resonance. The defected ground structure is integrated with a PIN diode to make reconfigurable EBG, and it resonated at C band (4 GHz). The PIN diode switching configuration embedded with EBG and one square patch creates dual-band characteristics in wireless local-area network (WLAN) and International Telecommunication Union (ITU) bands. Other PIN diodes switching configurations with primary antenna and two other patches work for C and WLAN bands. The proposed antenna resonated at 4, 5.2, and 6.33 GHz frequencies with different switching configurations of the PIN diode. The simulated results of this novel antenna configuration verified with measured consequences for antenna parameters like reflection coefficient and radiation characteristics are also presented.

Wide tunable range bandpass filter with three transmission zeros

This paper proposes a reconfigurable bandpass filter with a wide tunable range, which is achieved by connecting two tunable passbands with switching diodes. A pair of transmission zeros (TZs) are introduced through the cross-coupling structure to improve the passband selectivity of the filter, and one more transmission zero is added by the interdigital coupling line to enhance the out-of-band suppression and broaden the upper stopband. The simulation and experimental results show that the designed filter with an absolute bandwidth of 100 MHz realizes a tunable frequency band covering 1.5–3 GHz, corresponding to a fractional tunable range of 66.7%. The dimension of the fabricated filter is 0.32 λg × 0.34 λg.

Ionic diode desalination: Combining cationic Nafion™ and anionic Sustainion™ rectifiers

Microscale ionic rectifier effects are commonly observed in devices based on semipermeable ionomer coated on an array of microholes with potential applications in alternating current (AC) driven desalination and/or electroosmotic pumping. The efficiency of devices is dependent on ionic diode switching speed, the rectification ratio, and the design of materials and the ionic circuit. Here, a new circuit is proposed based on coupling in parallel (i) a cationic diode based on the cation conductor Nafion and (ii) an anionic diode based on the anion conducting Sustainion. With an alternating driving voltage, a net desalination effect is observed without any moving parts and without significant side reactions. Experimentally, a 4-electrode configuration and a 2-electrode configuration are compared. The ionic diode desalination system is shown to work with only two carbon mat driver electrodes, but the performance in particular at higher ionic strengths (>10 mM) still needs to be improved. Based on the experimental prototype, the current/power efficiency are investigated and challenges for future improvements are discussed.

A phase‐shift modulated series resonant converter achieving zero‐voltage and zero‐current switching for wide output voltage range battery charging applications

In this article, a phase-shift modulated zero-voltage and zero-current switching (ZVZCS) series resonant converter (SRC) was proposed for constant current (CC) and constant voltage (CV) charging operating at the series resonant frequency. Wide output voltage range is achieved by adjusting the duty cycle of the primary inverter for CC charging and unity gain is for CV charging at full duty cycle. By tuning resonant tank parameters, discontinuous conduction mode (DCM) and boundary conduction mode (BCM) are obtained in CC charging and CV charging, respectively, which ensures zero-current switching (ZCS) of rectifier diodes and nearly ZCS of leading leg in whole charging profile. Meanwhile, a constant triangular current provided by a novel auxiliary circuit is used to implement zero-voltage switching (ZVS) for all primary MOSFETs with a reduced conduction loss. The auxiliary current is independent of duty cycle and load variation. Compared with the conventional ZVZCS phase-shift full-bridge converter with capacitive output filter, smaller conduction loss and turn-off loss can be obtained in battery charging profile. Detailed circuit operation principles and model analysis are presented. A 100 kHz/1 kW prototype is built to verify the performance.

Machine learning assisted metamaterial-based reconfigurable antenna for low-cost portable electronic devices

Antenna design has evolved from bulkier to small portable designs but there is a need for smarter antenna design using machine learning algorithms that can meet today’s high growing demand for smart and fast devices. Here in this research, main focus is on developing smart antenna design using machine learning applicable in 5G mobile applications and portable Wi-Fi, Wi-MAX, and WLAN applications. Our design is based on the metamaterial concept where the patch is truncated and etched with a split ring resonator (SRR). The high gain requirement is met by adding metamaterial superstrates having thin wires (TW) and SRRs. The reconfigurability is achieved by adding three PIN diode switches. Multiple designs have been observed by adding superstrate layers ranging from one layer to four layers with interchanging TWs and SRRs. The TW metamaterial superstrate design with two layers is giving the best performance in gain, bandwidth, and the number of bands. The design is optimized by changing the path’s physical parameters. To shrink simulation time, Extra Tree Regression based machine learning model is used to learn the behavior of the antenna and predict the reflectance value for a wide range of frequencies. Experimental results prove that the use of the Extra Tree Regression based model for simulation of antenna design can cut the simulation time, resource requirements by 80%.

Design and Performance Analysis of MIMO Patch Antenna Using Superstrate for Minimization of Mutual Coupling

For 5G communications, An different types Antennas are plays major role to minimize mutual couplings and here MIMO is important technology which uses patch antenna’s. Where the existing design focuses only on frequency reconfiguration, but it does not take advantage of the entire frequency and power spectrum. Therefore, the honeycomb-shaped Metamaterial cells used in the suggested antenna design serve as a superstrate for micro-strip patch antennas with a extensive range of actual negative permittivity and permeability, as well as a refractive index feature. Also, to reduce mutual coupling in current printed and other antennas. A metamaterial superstrate-based micro-strip antenna with RF MEMS Varactor diode switching is proposed in this paper. Based on a micro-strip antenna, metamaterials in the shape of circular and hexagonal arrays are employed as the superstrate. Also, the superstrate layers serve as a random, providing strength to the entire structure while also improving other antenna metrics such as gain and bandwidth. The design outputs for several metamaterial superstrates in terms of reflection coefficient (S11), gain, and bandwidth are compared by adding varactor diode switches to the metamaterial superstrate, which also allows for frequency reconfiguration. As a result, the suggested antenna was designed to reduce mutual coupling and improve system performance in 5G technology, specifically in mm-wave applications. The obtained results for metamaterial superstrate designs demonstrate high bandwidth and gain behavior.

Velocity Estimation of Target in MIMO Radar Environment with Unknown Antenna Locations

A new algorithm is formulated for MIMO Radar system where positions of target along with that of the transmitter and receiver antennas are unknown. This algorithm considers a widely separated antenna MIMO setup and can be used when transmitters and receivers are either stationary or moving at a very low velocity. Here, the algorithm estimates the location of target with respect to the location of the first transmitter. The TDOA and AOA available for LOS path between the transmitters and receivers along with the reflection path from the target are utilized here. AOA is used only for initialization of antenna positions and target location. Furthermore, accurate estimation using Davidon-Fletcher-Powell (DFP) Algorithm is performed. The paper introduces a new algorithm to compute velocity of a target. Here, first the FDOA is estimated using a novel approach and then velocity is estimated from the FDOA obtained. The velocity estimator for FDOA given tracks CRLB and FDOA estimation tracks its corresponding CRLB upto -12dB. The algorithm uses target and antenna locations to estimate velocity that can be found out from the algorithm introduced in paper.

Demonstration of a superconducting diode-with-memory, operational at zero magnetic field with switchable nonreciprocity

Diode is one of the basic electronic components. It has a nonreciprocal current response, associated with a broken space/time reversal symmetry. Here we demonstrate prototypes of superconducting diodes operational at zero magnetic field. They are based on conventional niobium planar Josephson junctions, in which space/time symmetry is broken by a combination of self-field effect from nonuniform bias and stray fields from a trapped Abrikosov vortex. We demonstrate that nonreciprocity of critical current in such diodes can reach an order of magnitude and rectification efficiency can exceed 70%. Furthermore, we can easily change the diode polarity and switch nonreciprocity on/off by changing the bias configuration and by trapping/removing of a vortex. This facilitates a memory functionality. We argue that such a diode-with-memory can be used for a future generation of in-memory superconducting computers.

A gain enhanced linear polarization switchable array antenna with switching diodes

In this article, an array antenna possessing linear polarization switchable ability with enhanced gain is proposed by employing 4-patch elements in square shape. The 4-elements were arranged on the upper plane of the antenna where edge to edge distances were set to be 0.8λ of its operating frequency. The radio frequency signal was fed to energize the patch elements by means of a feed circuit which was realized by the both-sided microwave integrated circuit technology. In addition, polarization switching is done by simply utilizing diode at the corner of the elements as switching elements to perform beam tilting. The incorporation of extra Magic-T circuit to feed dc bias signal to the diodes helps to achieve improved isolation between feeding signal and the isolation was found to be less than −25 dB. The array antenna was designed to operate at 10.2 GHz and the dimensions of the patch elements was chosen to be 9.4 × 9.4 mm2. A Teflon glass fiber of 0.8 mm was used as the dielectric substrate having dielectric constant 2.15 while simulation. Later the proposed antenna was fabricated performance is validated experimentally. The measured S11 was found to be less than −15 dB at operating frequency with a neat measured gain of 13.1 dBi, higher compared with 7.1 dBi gain of single antenna, with minimized sidelobe levels of less than −10 dB. The crosspolarization for the radiation pattern was found better than 20 dB which was an excellent result. The measured polarization angle was found to be −44.24° and +46.20° for negative and positive bias respectively at operating frequency with a neat efficiency of more than 80% in its operating bandwidth. The proposed array antenna is a suitable candidate for the application in polarimetric Radar, X-band radar, and polarization diversity applications for being lightweight in structure which was made possible using this novel technology. The antenna simulation is done by the advanced design system and the optimized along with experimental data are discussed in this article.

Design of an Aerospace Langmuir Probe Volt-ampere Characteristic Load Simulator

The development process of space Langmuir probe needs to complete a large number of tests and calibration tests on the ground. Due to the long calibration period, complexity and high cost of plasma environment calibration, calibration tests are usually carried out after the instrument has been developed, in order to conduct preliminary tests on Langmuir probe during the instrument development process to verify the performance, as well as to save the cost of calibration tests and increase the reliability of the instrument, An advanced spatial Langmuir probe volt-ampere(I-V) load simulator was designed in this paper. Based on the positive and negative polarity of the external bias voltage, the I-V characteristic curve of the Langmuir probe was divided into positive and negative characteristic curves, which were realized by the combination of the output characteristic curves of NPN and PNP transistors, and the diode switching selectivity. The laboratory test results were consistent with the theoretical curve, verifying the validity and compliance of the design, which can play an important role in supporting the development of the space Langmuir probe and the calibration of the plasma environment.

A Power Quality Improved EV Charger by Using Bridgeless CUK Converter

Abstract: This study designs and develops an improved bridgeless (BL) Cuk converter-based electric vehicle (EV) battery charger with a high-power factor and higher efficiency. It offers a low-cost, high-power-density-based charging solution for EVs. This charger has fewer components functioning during a single switching cycle, which decreases the extra conduction loss experienced by the typical charger's diode bridge rectifier. As a result, it boosts the charger's efficiency. The suggested topology also avoids the undesired capacitive coupling loop and unwanted conduction via the body diode of the inactive switch in the previously developed BL Cuk converter. This considerably enhances the charger's efficiency. A flyback converter synchronises the orders for constant current and constant voltage charging. The suggested charger draws a sinusoidal current from an alternating current main, and the overall harmonic distortion in the supply current is kept within the IEC 61000-3-2 requirements. The suggested charger's increased efficiency and power quality indices are studied to verify its good charging performance under all operational situations. Keywords: Bridgeless (BL) Cuk converter, discontinuous conduction mode (DCM), flyback converter, power factor correction (PFC), and power quality are all terms used to describe a battery charger (PQ).

Optimal design of cascaded Wiener-Hammerstein system using a heuristically supervised discrete Kalman filter with application on benchmark problems

Block oriented models are recurrently employed to describe the dynamic characteristics of nonlinear systems. This paper adopts an efficacious block-oriented model called cascaded Wiener-Hammerstein (W-H) structure to model a nonlinear system. The parameters of the W-H model are identified using a nature-inspired evolution algorithm-supported Kalman filter (KF). In the proposed technique, the utility of the employed optimisation algorithm named Harris Hawks optimiser (HHO) is to acquire the optimal global solution of initial state KF parameters for the W-H system identification problem. Then, the conventional KF algorithm utilises these optimised KF parameters to beget the near-global estimated W-H system parameters. The effectiveness of the proposed HHO-based KF algorithm is verified through a comparison study with other variants of particle swarm optimisation (PSO) and harmony search (HS) algorithms-supported KF methods on two numerical W-H problems with different nonlinearity levels and two practical benchmark plants, namely, real electronic diode switching network and flutter clearance of F-18 systems research aircraft. The simulation results ensure that the proposed HHO-KF approach offers significantly improved results over other competing methods in terms of various well known standard metrics. The hypothesis test verifies the stability and consistency of the proposed identification method. Moreover, the proposed approach provides a faster convergence rate and the lowest estimation precision compared with other reported techniques.

Design of an Absorptive High-Power PIN Diode Switch for an Ultra-Wideband Radar

This paper details the development of a low-loss, PIN diode single-pole double-throw (SPDT) absorptive switch for an ultra-wideband radar. The fabricated switch operates with a peak power of 200 watts at a 10% duty cycle. It has an insertion loss of less than 0.8 dB, a return loss greater than 19 dB, and isolates the transmitter and receiver beyond 37 dB over the frequency band (170 MHz-470 MHz) for sensitive radar measurements. An external RF limiter and a low-power CMOS switch at the receiving end are used to reduce video leakage from the PIN diode switch and enhance the isolation up to 80 dB. In addition, a fast-switching MOSFET-based PIN diode driver circuit is designed with a dead-time control circuit to minimize the cross-conduction currents for the PIN diode switch. The rise and fall times for the PIN diode switch are less than 200 ns. The switch-driver includes integrated low-noise power supplies that generate −50 V, 15 V, and 5 V from a common rail 50 V input source.

A low profile single feed compact dual-band penta-polarization agile microstrip antenna for interference mitigation in point to point link in Ultra-Dense environment

This study takes an antenna perspective approach to mitigate signal interference issues in ultra-dense environment along with communication and signal processing domain. A compact single layered dual-band penta-polarization agile microstrip patch antenna (MSA) using single feed is studied and proposed. Each band switches between five distinct polarization states. Additionally, the proposed antenna possesses a very low profile of less than 0.01λ (λ free-space wavelength). A square patch is enclosed by a square ring to attain two distinct reconfigurable frequency bands by using switching diodes and biasing networks. Orthogonal microstrip lines connected with a single coax feed are selectively chosen by biasing network to excite the adjacent patch edges to achieve dual linear polarization (LP). Circular polarization (CP) with dual sense of rotation at each band is attained by switchable diagonal-truncated corners of outer ring. Subsequently, 45° slant polarization is achieved by simultaneous activation of the orthogonal feed lines with equal phases and amplitude. A penta-polarized antenna prototype is designed and fabricated to operate at 5.2 GHz and 5.8 GHz bands respectively. Simulation results of all ten reconfigurable states are found to be consistent with the measurement.

Presenting of the Magnetic Coupling-Based Transformer-Less High Step-Up DC-DC Converter for Renewable Energy Applications

This study presents a new high step-up converter based on the voltage multiplier cell and coupled inductor for renewable energy applications such as fuel cell and photovoltaic power systems. This converter achieves a high voltage conversion ratio using a coupled inductor and voltage multiplier cell (VMC). The voltage multiplier cell acts as a passive clamp circuit and reduces the maximum voltage across the power switch. The suggested topology has only one power switch in its structure, which leads to low cost and volume. The other benefits of the proposed structure are low components count, low input current ripple, low voltage stress throughout the semiconductors, high efficiency, zero-current switching (ZCS), and zero-voltage switching (ZVS) of diodes. Besides, due to the soft-switching condition of the diodes, the reverse recovery problem can be decreased. To show the effectiveness of the suggested topology, operation survey, steady-state analysis, and efficiency calculation are provided. Additionally, the comparison study with other similar converters illustrates the superiority of the proposed structure. Finally, an experimental prototype with 150 W rated power, 50 kHz switching frequency, and 24 V input voltage is implemented to prove the mathematical analysis and effectiveness of the proposed DC-DC converter.

Low profile multiband microstrip patch antenna with frequency reconfigurable feature using PIN diode for S, C, X, and Ku band applications

SummaryThe proposed work represents a simple and effective approach to achieve frequency tunability. The tunability is attained by the switching mechanism of the two PIN diodes. The biasing issue is reduced due to the usage of two PIN diodes. Simulation is carried by a high‐frequency structure simulator tool and compared with the fabricated structure for the authentication. Antenna fabrication is performed by low‐profile material FR‐4. Three modes were analyzed and compared in terms of resonating frequency, reflectance response, gain, bandwidth, and electric field based upon switching of PIN diodes. The proposed antenna structure provides a multiband response with the four frequency tunable bands along with maximum frequency tunability of 700 MHz and a minimum reflectance response of −28.22 dB. The proposed structure opens a new door of applications like satellite communication, military, and a sensor for the S, C, X, and Ku bands. The presented design was also compared with the previously published papers to identify the improvement.

Wideband RF Transmit-Receive Switch for Multi-Nuclei NMR Spectrometers

The utility of wideband high field nuclear magnetic resonance (NMR) spectrometers is significant in many applications. Wideband radio frequency (RF) front-ends are critical for the realization of multi-nuclei spectrometers. To realize such systems, wideband Transmit-Receive (TR) switches and low noise amplifiers (LNA) should be implemented at the RF front-end (FE) of the system. Most of the common designs used nowadays on NMR spectrometers are either inherently narrowband and/or of relatively high noise-figure which limit the overall system performance to a large extent. To improve upon the conventional FE performance, a new design of wideband high-power TR switch which could be devised for multi-nuclei NMR spectrometers is introduced in this brief. The developed wideband TR switch employs PIN diode switching technique and a dual-driver circuit. A prototype was constructed and experimentally characterized. The small-signal measurement results show that the switch has a bandwidth from 30 – 200MHz where the return loss is maintained below 18 dB with insertion loss of 0.09 - 0.2dB in the transmit mode and 0.11 – 0.37dB in the receive mode. It also exhibits a very high isolation of 63 - 80dB over the entire bandwidth. It is demonstrated that the switch can withstand continuous-wave RF input with power levels as high as 125 W while maintaining low insertion loss and high isolation.

Design and analysis of frequency reconfigurable antenna for global positioning system applications

A compact frequency reconfigurable antenna is designed and analyzed in this paper to operate with global positioning system (GPS) and worldwide interoperability for microwave access (WiMAX) applications. The designed antenna is printed on flame resistant 4 (FR4) epoxy substrate with relative permittivity is 4.3, loss tangent of 0.03 and overall substrate with ground (GND) plane dimensions of (54.6x54.6x1.6) mm3 and patch dimensions of (45x45) mm2. The antenna is designed and optimized using computer simulation technology (CST) package through series of parametric studies in order to cover the GPS, WiMAX bands with resonant frequency of 1.229 GHz, 1.575 GHz, and 3.34 GHz. Two triangular slots at the patch sides and single elliptical slot at the middle are etched for the best antenna performance. The designed antenna performs frequency re-configurability by using PIN diode switch at the inset feed to change the operating frequencies from double band operation at (1.575 and 3.34) GHz to single band at 1.229 GHz under S11 ≤-10 dB. The proposed antenna produces accepted simulation results with voltage standing wave ratio (VSWR), maximum radiation efficiency and gain of less than 2.76% and 7.035 dBi respectively.