We present the formulation and experimental results of a new approach to designing internal mode converter reflectors for high-power gyrotrons. The method employs a numerical phase retrieval algorithm that reconstructs the field in the mode converter from intensity measurements, thus accounting for the true field structure in shaping the beam-forming reflectors. An outline for designing a four-...

In direct digital synthesizer (DDS) applications, the drawback of the conventional delta sigma ( ) modulator structure is that its signal band is fixed. In the new architecture presented in this paper, the signal band of the modulator is tuned according to the DDS output frequency. We use a hardware-efficient phase-to-sine amplitude converter in the DDS that approximates the first quadrant of t...

This paper presents a novel method to calculate the reference source current and the referencecompensating current for shunt active power filters (SAPFs). This method first calculates theamplitude and phase of the fundamental load current from a recursive algebraic approach blockbefore calculating the displacement power factor. Next, the amplitude of the reference mains currentis computed with ...

A pipelined analog-to-digital converter (ADC) has been investigated, which has a programmable gain achieved by the gain control in a first-stage multiplying digital-to-analog converter (MDAC). The current consumption reduction under low gain is realized by controlling the transconductance and compensation capacitor of the MDAC circuit according to the input gain. The pipelined ADC designed usin...

Voltage domain ADC architectures require high gain and bandwidth opamps to amplify the signal for successive stages. The opamp design gets a bit challenging due noise, small lower overdrive voltage. Due these limitations, inclination shifted towards high-speed converters which don’t opamps. Time based Analog Digital Converters (TBADC) is one such category of circuits. TBADCs are constituted fro...

This CMOS interface circuit is used in a radar system that digitizes the reflected signal by a multi-gigahertz analog-to-digital converter (ADC) employing Josephson junctions, producing a returnto-zero (RZ) differential binary stream with 2mV peak-to-peak amplitude at 1.2Gb/s. The interface amplifies, detects, and demultiplexes the signal, generating a parallel output with 1Vpp amplitude at 150...

The accuracy of rotor position estimation in the (several kHz), and its amplitude cannot be changed as it is conventional signal injection based sensorless control of determined by the DC-link voltage and the PWM duty cycle, permanent magnet brushless AC drives depends on the load the amplitude of high frequency current will be too small for current. This paper proposes an improved method, whic...

The matrix converter instability can cause a substantial distortion in the input currents and voltages which leads to the malfunction of the converter. This paper deals with the effects of input filter type, grid inductance, voltage fed to the modulation algorithm and the synchronous rotating digital filter time constant on the stability and performance of the matrix converter. The studies are ...