High Gain Capability Research Articles

An Endfire Periodic Leaky Wave Antenna With Wideband and High-Gain Capability by Manipulating Its Higher-Order Space Harmonics

An Endfire Periodic Leaky Wave Antenna With Wideband and High-Gain Capability by Manipulating Its Higher-Order Space Harmonics

Design of High-Gain Magneto-Electric Dipole Antenna by Loading a Magneto-Electric Dipole Director

A high-gain magneto-electric dipole (ME-Dipole) antenna has been designed by adding a ME-Dipole director on top of a conventional cavity-backed ME-Dipole antenna. The purpose of adding the ME-Dipole director is to significantly enhance the gain of the antenna. The proposed design has been both measured and simulated, with an average gain of 12.5 dBi and 12.4 dBi, respectively, demonstrating the design's high gain capabilities. Additionally, the measured and simulated impedance bandwidth (VSWR ≤ 2) are 29.21% (1.90 GHz - 2.55 GHz) and 30.70% (1.93 GHz - 2.63 GHz), respectively, confirming the wideband nature of the design. Other outstanding performance metrics, such as low cross-polarization of - 25 dB and the stable antenna gain of 11.8 ± 1.7 dBi as measured and 12.0 ± 1 dBi as simulated, have also been observed in the current design.

A Millimeter-Wave Resonant Cavity Antenna With Multibeam and High-Gain Capabilities for 5G Applications

In this article, a technique to obtain a high-gain multibeam antenna for millimeter-wave (mmW) fifth-generation (5G) base stations (BSs) is proposed using the Fabry–Pérot Cavity (FPC) structures. A thin single metallodielectric layer is used as the partially reflective surface (PRS) layer to enhance the radiation performance of the FPC antenna (FPCA) and provide an off-axis pencil beam. As the feeding structure illuminating the PRS layer, a cylindrical cavity is designed using a right-angle-type semi-waveguide (RATSW) structure. An array of coaxial probes is used to obtain beam switching at the azimuth plane by exciting different probes. To confirm the functionality of the proposed FPCA, a prototype is fabricated with five coaxial probes to generate five radiation beams; however, the structure can be extended to provide more antenna beams using higher number of probes. The cavity structure of the proposed antenna is fabricated by the 3-D printing technology as an easy manufacturing process. The measurement results show that multiple switchable beams with high antenna gain are obtained over the desired frequency bandwidth of 27–30 GHz. The maximum measured gain is 19 dBi at 27.5 GHz when a single probe is excited. A conceptional scenario for the potential applications of the proposed antenna in the 5G BSs is presented.

Substrate Integrated Waveguide Antenna at Millimeter Wave for 5G Application

This paper presents a dual-band slot antenna using substrate integrated waveguide (SIW) technology at 26 and 28 GHz. High loss is one of the main challenges faced by 5G base station network due to the severe path loss at high frequency. Hence, high gain antennas are required for 5G base station applications to overcome path loss issue. Hence, this work designs a high gain SIW antenna based on slot technology to excite dual-bands with high gain capability. The antenna is designed with two slots shaped to resonate at two different frequencies: 26 and 28 GHz. The antenna is analyzed using CST software and fabricated on Roger RT5880 substrate with permittivity of 2.2 and lost tangent of 0.0009 with thickness of 0.508 mm. The design operates at 26 and 28 GHz with measured reflection coefficients less than -10 dB. Measured high gains of 8 and 8.02 dB are obtained at 26 and 28 GHz, respectively. Overall, the antenna showed good performance that would benefit the fifth-generation applications.

An improved frequency compensation for three‐stageCMOSamplifier

AbstractMulti‐stage operational amplifiers are considered as basic building blocks in modern electronics since advanced Complementary metal–oxide–semiconductor (CMOS) technology limits exploiting cascode structures due to suffering from low voltage swings and the need of high gain capability. In this regard, an improved and high‐performance three‐stage CMOS amplifier is proposed in this work. The presented structure modeled mathematically and simulated via HSPICE circuit simulator with the 0.18‐μm CMOS technology. An straightforward symbolic calculation is explained to obtain linear transfer function. According to the simulation results, the proposed circuit show 149 dB as DC gain while express 7.3 MHz and 380 μW as gain‐bandwidth product and power dissipation, respectively. Such a high‐performance amplifier has great potential to realize more complex analog and mixed mode signal systems such as modulators and data convertors.

High‐gain three‐phase current‐fed push–pull DC–DC converter

In this study, a new three-phase current-fed push–pull DC–DC converter with high-gain capability was proposed. The proposed circuit has the advantages of three-phase converters and the push–pull converter circuit, with small volume and a simplified gate drive circuit with switches connected to the same reference. The converter was analysed for operation in continuous and discontinuous conduction modes. The analysis includes a description of the topological stage, theoretical waveforms, deduction of the voltage gains and the expressions for its practical design. To validate the theoretical analysis, a 700 W prototype was built and tested with an input voltage of 40 V, an output voltage of 400 V and a switching frequency of 40 kHz. Despite using a unity transformer turns ratio, the prototype had an experimental gain of ∼10, which makes the proposed converter suitable for applications as renewable energy sources systems.

Accurate Theoretical Model for the High-Frequency Characteristics of the Ladder Multigap Resonant Cavity

The ladder multigap resonant cavity finds wide application in the terahertz vacuum electric devices. It consists of a single slotted plate (called ladder) enclosed by a rectangular waveguide, which offers advantages in mechanical simplicity as well as the capability of high gain per circuit length and frequency tuning. The theoretical model for the high-frequency characteristics of such circuit was developed. The derivation of the characteristic impedance ( $R/Q$ ) and the intrinsic quality factor ( $Q_{0}$ ) in combination of the established dispersion relation enables a complete analysis for this circuit. Examples at the terahertz frequencies were used to demonstrate the usefulness of the theoretical model with the 3-D finite-element electromagnetic simulation as a benchmark. The formula system is described and the computational results are presented.

A New Hybrid Boosting Converter for Renewable Energy Applications

A hybrid boosting converter (HBC) with collective advantages of regulation capability from its boost structure and gain enhancement from its voltage multiplier structure is proposed in this paper. The new converter incorporates a bipolar voltage multiplier, featuring symmetrical configuration, single inductor and single switch, high gain capability with wide regulation range, low component stress, small output ripple and flexible extension, which make it suitable for front-end PV system and some other renewable energy applications. The operation principal, component stress, and voltage ripple are analyzed in this paper. Performance comparison and evaluation with a number of previous single-switch single-inductor converters are provided. A 200-W 35 to 380 V second-order HBC prototype was built with peak efficiency at 95.44%. The experimental results confirms the feasibility of the proposed converter.

Design of Hybrid Boost Converter for Hybrid Renewable Applications

In this work discuss about hybrid power system generation and its control strategy using Hybrid Boost Converter (HBC) with high boost ratio. The new converter incorporates a bipolar voltage structurer, featuring symmetrical configuration and three switch, high gain capability with wide regulation range, low component stress, small output ripple and flexible extension, which make it suitable for front-end hybrid system and some other renewable energy applications. The operation principal, component stress, and voltage ripple are analyzed in this paper. The proposed HBC system consists of a wind turbine, a battery storage unit, PV cell and a set of loads. The energy management and power regulation system based on wind and PV generation systems. The proposed regulation system also controls the load scheduling operation during unfavorable wind conditions under inadequate energy storage in order to avoid a system blackout. Based on the reference dynamic operating points of the individual subsystems, the local controllers control the wind turbine, and battery storage units. The proposed control system is implemented in MATLAB Simpower software and tested for various wind and load conditions.

Power Stability of Novel Converters using Stochastic Pattern Controller for Hybrid Renewable Energy Applications

This paper proposes a novel converter and a stochastic control strategy for Hybrid Renewable Energy System (HRES) for a stand-alone and grid-connected operation of power systems. The proposed hybrid system consists of a wind turbine, a PV, battery storage unit, inverter and a set of loads. The overall control strategy is based on Neural Network Stochastic pattern controller structure. The control concepts in an HRES and the application of the appropriate control schemes for system stabilization, efficient injection of high-quality power and proper load sharing are implemented. A stochastic pattern control for power stability of different Boost converter with high boost ratio from its regulation voltage structure is designed. The proposed stochastic pattern regulation system control is used to enhance the high gain capability with wide management range, low component stress, small output ripple and flexible extension. These features make the proposed controller to be suitable for renewable energy applications. The proposed controller mode of operation, controller design, and efficiency, losses are analyzed using MATLAB simpower software and tested for variable wind and load conditions.

Performance of Medium-Voltage DC-Bus PV System Architecture Utilizing High-Gain DC–DC Converter

The number of large-scale solar photovoltaic (PV) systems continues to increase, while the size of the largest systems has already reached several hundred megawatts. This trend will challenge existing PV system architectures and will require new PV system architectures with higher power ratings and higher voltage levels at the point of common coupling (PCC). This paper reports a medium-voltage (MV) dc-bus PV system architecture based on a high-gain soft-switched interleaved boost (SSIB) dc-dc converter. The interleaved characteristic increases the flexibility of the converter, allowing for either a higher voltage and/or current rating, thus increasing the power rating of the converter. The high-gain capability of the SSIB converter allows it to be connected directly to an MV dc bus. This will facilitate direct connection of a PV system to an MV ac grid (i.e., 20 kV) using only one step-up transformer. Simulation and experimental results are presented to verify the operation of the SSIB converter and to confirm the steady-state and dynamic performance of the proposed PV system architecture.

Amplifiers for use with photomultipliers—who needs them?

Photomultipliers (pmts) incorporate an electron multiplier to provide high gain with fast response. However, the high gain capability must sometimes be restricted and external gain sought because of performance limitations of the pmt. Amplifiers also perform impedance transformation and pulse shaping which is important to pulse height encoding and timing.

A new multi-grid type MSGC with pad readout

Recently, a new multi-grid type MSGC has been proposed. Between the anode and the cathode, additional grid strips are placed in this new type of MSGC. Gaps between these strips are chosen to be around 10 μm which assure efficient removal of surface charges which even do not need the lower surface resistivity and bare glass can be used up to 10 6 cps/ mm 2 . Another feature of the MSGC is its high gain capability. Owing to the existence of other strips of lower potentials, the field strength around the opposing grid to the anode strip is not so high as conventional small gap detectors. Furthermore, the contribution of the surface streamer is greatly suppressed because the electric field parallel to the surface is screened by the intermediate grid electrodes. However, the existence of additional electrodes also screens all the electric field upper than the substrate and we cannot observe induced signals from backside of the substrate. To overcome the difficulty, we propose another signal readout method using patterning approach. Floating pads are placed close to the cathode strip on the surface of the M-MSGC and induced charges are read out via the pads. If the area of pads is sufficiently large and the positive charges are moving toward the pads, backside electrodes can sense the induced charge. Collected charges on the pads are leaked through the surface resistivity. The basic experiment has been performed and the readout of the position along the cathode strips is successfully ensured.