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Micromachined Microwave Phase Shifters
Published in Shiban Kishen Koul, Sukomal Dey, Radio Frequency Micromachined Switches, Switching Networks, and Phase Shifters, 2019
Shiban Kishen Koul, Sukomal Dey
A phase shifter is one of the most essential microwave components in modern phased arrays and provides a controllable phase shift of the radio frequency (RF) signal. The primary job of a phase shifter is to change the transmission phase of the input microwave signals with the electrical control signal applied to the component to get the phase shifted output signal. Based on the applications, phase shifters are broadly classified into two categories: active and passive. Besides providing controlled phase shift, active phase shifters provide gain, whereas passive phase shifters are lossy. The gain of the active phase shifter is defined when the phase shifter amplifies while phase shifting, whereas in passive phase shifters the loss is defined when the phase shifter attenuates while phase shifting. The active phase shifters are generally nonreciprocal in nature, whereas passive phase shifters can be both reciprocal as well as nonreciprocal. Phase shifters are widely employed in active or passive electronically scanned arrays that are based on phased antenna arrays. In addition, RF and microwave phase shifters find applications in subsystems such as phase discriminators, beam-forming networks, variable power dividers and linearization of power amplifiers.
TV Antennas for Cars
Published in Victor Rabinovich, Nikolai Alexandrov, Basim Alkhateeb, Automotive Antenna Design and Applications, 2010
Victor Rabinovich, Nikolai Alexandrov, Basim Alkhateeb
Figure 6.3 illustrates a linear passive phase array with electronic beam control. The system consists of N linear equally spaced identical antenna receiving elements. Each element has a phase shifter controlled electronically by a special beam control block with computer. Each phase shifter has a special electrical control circuit (for example, a pin diode) that can change the phase of the received signal. The computer calculates the phases for each element in such a way to direct the beam (maximum receiving) at a predetermined angle. The control block converts the calculated phases into the electrical signals, and these control signals change the phase shifter states, collimating maximum energy received by the array at the given direction.
Signal Conversion Methods
Published in Clarence W. de Silva, Sensor Systems, 2016
A phase shifter changes the phase angle of a signal. Consider a sinusoidal signal given by () v=vasin(ωt+ϕ)
Determination of Maximum Loadability by a Mixed Complementarity Formulation of the Adjusted Power Flow Problem
Published in Electric Power Components and Systems, 2018
Sunil S. Damodhar, Krishna Suryanarayan
The method of fixing the constrained variables at their limits is employed in several other methods devised to deal with transformer taps and phase-shifter angles such as in [4]–[6]. Generalized nodal admittance models for series compensators, phase-shifters, and other power flow controllers, and their inclusion in the power flow problem is presented in [4]. In [5], the effect of phase-shifter is modeled using the injected complex powers at the terminal buses. The phase-shifter angle is treated as a variable. While the augmented Jacobian method in [3] seems to be the most attractive way, the method is limited to cases where the voltages and active power flows are held at specified values. It is straightforward to incorporate limits in an optimization problem such as optimal power flow; the limits are incorporated in the form of inequality constraints [6].
Design of compact wideband 90° Schiffman phase shifter incorporating CSRR
Published in Electromagnetics, 2020
Partha Kumar Deb, Tamasi Moyra, Bidyut Kumar Bhattacharyya
In RF and microwave engineering, phase shifter is one of the most essential components that are used extensively in phase discriminators, beamforming networks, power dividers, electronic beam-scanning phased arrays, etc. A phase shifter is a two-port device whose basic function is to provide a change in phase of an RF signal with practically negligible attenuation. Schiffman phase shifter is one of the most popular ones because of its simple design and broadband characteristics (Pozar 2011).