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This paper presents a novel RF rectifier that compresses RF input impedance fluctuation caused by DC load change for reducing return loss at RF input power. The proposed rectifier connects twin basic RF rectifiers and a quarter-wave impedance transformer. The proposed rectifier automatically switches the two rectifiers according to DC load resistance. As the result, the rectifier can keep low deviation...
This paper discusses the fault classification and detection applying Discrete Wavelet transform (DWT) approach of differential relaying based SVC (Static Var Compensator) compensated transmission line. The SVC is located at middle part of transmission line. Fast detection of faults and fault classification helps restoration of supply, which enhances the economy and reliability of the power supply...
This paper discusses the coupling of two dimensional and one dimensional nano-materials to electromagnetic waves across the spectrum, from RF to light wave.
This work presents an efficient power delivery network design for mitigating the coupling of power supply noise in mixed-signal electronics using power transmission lines. Digital circuitry operating at high data rates generates supply noise that can interfere with sensitive RF circuitry. Currently used methods, such as split planes and ferrite beads, have limited isolation bandwidth and can pose...
This work presents a development of multi-way transmission-line resistance compression networks (TLRCNs) and their application to rf-to-dc conversion. We derive analytical expressions for the behavior of TLRCNs, and describe two design methodologies applicable to both single- and multi-stage implementations. A 2.45-GHz 4-way TLRCN network is implemented and applied to create a resistance-compressed...
The gain/linearity trade-off is exploited to achieve the best linearity performance of a mm-Wave down-conversion system. The achieved linearity (IIP3) for the whole down-conversion chain is better than 11.06dBm for 5.8dB gain at 60GHz. Gain can be adjusted from −15dB to 11dB in 1dB steps depending on the signal level. By adjusting phase matching at RF input and the common-mode impedance of the mixer...
Different kinds of RF power combiner are studied. Wilkinson and hybrid combiner show very good linearity but low power efficiency. Chireix combiner using stubs at the input shows good efficiency and bad linearity of system. This paper shows that an unmatched chireix combiner without stub used at the output of class-B amplifiers can be optimized in transmission line length in order to obtain the same...
Performance of thru-only cascade de-embedding methods and their variants that use a Π- or a T-equivalent to represent and bisect a symmetric THRU is assessed. The results from the Π- and T-based methods are reasonable at low frequencies. However they are shown to deviate noticeably from the correct results as the frequency gets high or, equivalently, when the length of the THRU approaches an effective...
A novel 900 MHz outphasing power amplifier using LDMOS transistors has been developed. It uses a distributed active transformer for high efficiency impedance transformation and lossless power combining. The current mode class-D amplification technique is applied to amplify constant envelope and outphasing signals. The outphasing power amplifier has been tested with the wideband code division multiple...
Phase and ground directional elements are relied on for fast and secure protection throughout the power system. Although directional relays have been applied successfully for many years, several new and unique applications and power system disturbances present challenges. Using field and laboratory data, this paper reviews fundamentals, discusses the limits to sensitivity, and shows how and why directional...
FAST (Fusion Advanced Studies Torus), a new tokamak machine for researches on Fusion Energy, has been proposed to the EU partners by the Italian Fusion Association to support the International Thermonuclear Experimental Torus (ITER) programme and to explore fusion relevant technologies. It is a compact tokamak with high toroidal magnetic field (8.5 T) and plasma current (up to 8 MA). In order to investigate...
A switching mode RF power amplifier that employs a narrowband filter directly connected to the output, is presented. The efficiency improvement compared to a conventional class B PA and the influence of a transmission line between the PA and this filter is investigated. These techniques are illustrated by circuit simulation and verified by measurements. It is shown how the transmission line between...
In recent years there has been great interest in the study of nonlinear lumped element transmission lines for applications in high power RF generation. The line lumped elements account for the line dispersion while reverse varactor diodes or saturated inductors (used as nonlinear elements C & L, respectively) are responsible for the nonlinearity characteristics of the line. Both properties of...
This paper analyzes a 300 ohm primary ground fault, which is an unusually high value for a 525 kV transmission line in southeastern Brazil. This case study emphasizes the techniques used by the analysts. Considering that the fault impedance was larger than those usually observed in single-phase faults on extra-high-voltage (EHV) lines, this paper discusses the probable cause of the fault and mentions...
This paper presents a novel methodology for automated testing of fault locator algorithms and testing their output sensitivity. The proposed methodology is based on Quasi Monte Carlo technique implemented in SIMLAB. The proposed methodology interfaces among SIMLAB, MATLAB and EMTP/ATP programs. A case study with a number of simulated fault locations along a transmission line is presented in the paper...
A reconfigurable phase shifter has been developed with enhanced phase variation without compromising the impedance matching performance. The phase shifter is based on a distributed MEMS transmission line (DMTL). A slow-wave structure is coupled with the DMTL to improve the phase shift and to reduce the dimensions of the device. The optimisation process has been performed using a lumped element model...
Impedance-based fault location methods are the most commonly ones used in practice due to their simplicity and low cost. However, the accuracy of such algorithms can be significantly affected by several sources of error, such as the fault resistance, the fault location, the source impedances, and the transmission line modeling. The aim of this paper is to evaluate the sensitivity of one-terminal and...
This paper presents a novel approach in order to construct low-loss reconfigurable impedance matching networks and tuners using MEMS series-contact switches and periodic defected-ground-structures (DGSs) implemented on coplanar waveguide (CPW) transmission lines. The application of DGSs results in an improved insertion loss and power handling capability compared to the conventional RF MEMS impedance...
This paper presents a novel MEMS-based reconfigurable multi-band power amplifier (PA) that employs a newly proposed reconfigurable biasing network and partitioned LTCC substrates. The biasing network comprises transmission lines, capacitors, and switches. Because DC bias current does not flow through switches, the proposed network functions as a multi-band low-loss biasing network. The partitioned...
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