Phase Shifter


Also found in: Acronyms.

phase shifter

[′fāz ‚shif·tər]
(electricity)
A device used to change the phase relation between two alternating-current values.

Phase Shifter

 

a device used in automation, conversion technology, and measuring technology to change the phase of electromagnetic oscillations. The design of a phase shifter depends on the range of operating frequencies, the limits of the phase change, and the accuracy of the equipment. Four-pole networks consisting of resistors, induction coils, and capacitances are usually used as phase shifters for low frequencies and in the radio-frequency range (up to several megahertz).

The simplest type of phase shifter consists of a phase-shift circuit composed of a resistor and a capacitor or of a resistor and an induction coil. Such phase shifters are usually used to produce a fixed phase shift within a range from 0° to 90°. More advanced types consist of a bridge circuit with three resistors and one capacitor; such designs produce an adjustable phase shift in the range from 0° to 180° with small changes in the magnitude of the output signal. Transistor and electron-tube phase shifters with bridge circuits are also used; they feature a phase inverter with a divided load as one of the network components. The phase shift produced is 180°. In the designs mentioned, the phase shift obtained depends on the frequency. This drawback is eliminated in follow-up phase shifters, in which any deviation of the phase shift from a specified value is automatically corrected by changing the parameters in such a way that the deviation is reduced.

Rotary transformers, selsyns, and three-phase asynchronous electric motors with blocked rotors are used for phase adjustment in AC circuits powered from mains rated at frequencies standardized for industry. Phase shifters for decimeter and shorter wavelengths are assembled from sections of coaxial lines and waveguides. The error of phase adjustment is from 0.5° to 1° for electromechanical phase shifters and from 0.05° to 0.1° for electronic phase shifters.

REFERENCES

Valitov, R. A., and V. N. Sretenskii. Radiotekhnicheskie izmereniia. Moscow, 1970.
Avramenko, V. L., Iu. P. Galiamichev, and A. A. Lanne. Elektricheskie linii zaderzhki i fazovrashchateli (handbook). Moscow, 1973.
Kushnir, F. V. Radiotekhnicheskie izmereniia, 3rd ed. Moscow, 1975.
References in periodicals archive ?
Ferrari, "Compact and broadband millimeter-wave electrically tunable phase shifter combining slow-wave effect with liquid crystal technology," IEEE Transactions on Microwave Theory and Techniques, vol.
The quadrature booster is a type of the phase shifter which allows obtaining the phase shift between voltage [[bar.V].sub.BT] and voltage [[bar.V].sub.i] equal to -90[degrees] or 90[degrees].
where i is an iteration count, PF(i) is the i-th measured power factor, y is the phase shift generated by the variable phase shifter, [f.sub.L](i) is the i-th measured line frequency, and [f.sub.AFE] is the sampling frequency used for the AFE, i.e.
Two-dimensional periodic modulations are utilized by the DRFP discussed in last sub-section, where a phase shifter and a DDS are needed.
The starting circuit in this modeling is the fully-distributed CRLH based phase shifter shown in Fig.
From Table 2, we can find that the points of [P.sub.1] and [P.sub.3] are two solutions of T model for 90[degrees] dual frequency phase shifter, and [P.sub.2] = [P.sub.4] = 0 means that T-model can be as transmission line without stub loaded.
The predistortion circuit consists of a power divider, two power combiners, three variable phase shifters, a variable attenuator, a directional coupler and an auxiliary amplifier.
By this we mean the following procedure: for a fixed phase shifter position, neutrons are counted in both cell positions, first in the sample and thereafter in the reference position, say.
There are linear arrays in which the antennas are in a single line - which is narrowed and directed by the phase shifters in a plane (for example, the horizontal plane).
The telecommunications segment in the global analog phase shifter market is expected to pick up pace in 2020, when the segment is anticipated to reach a valuation of over US$ 60 Mn by the end of 2020.
[ClickPress, Mon Jan 07 2019] A new report titled " Global Analog Phase Shifter Market Prospects and Growth Assessment Presented Until the End of 2027 " has been included in the enormous research repository of Market Research Reports Search Engine (MRRSE) that compiles various facets of the Analog Phase Shifter market at a global level portraying a holistic analysis of the marketplace along with intelligence on key participants.