{{Short description|Microwave network module}} {{Prose|date=July 2019}} {{about|the microwave device|the guitar effect|Phaser (effect)}} {{redirect|Phase shifter|the type of electric utility transformer|quadrature booster}} thumb|right|A microwave (6 to 18 GHz) Phase Shifter and Frequency Translator

A '''phase shift module''' is a microwave network module which provides a controllable phase shift of the RF signal.<ref>Microwave Solid State Circuit Design, 2nd Ed., by Inder Bahl and Prakash Bhartia, John Wiley & Sons, 2003 (Chapter 12)</ref><ref>RF MEMS Theory, Design and Technology by Gabriel Rebeiz, John Wiley & Sons, 2003 (Chapter 9-10)</ref><ref>Antenna Engineering Handbook, 4th Ed., by John Volakis, McGraw-Hill, 2007 (Chapter 21)</ref> Phase shifters are used in phased arrays.<ref>Phased Array Antennas, 2nd Ed., by R. C. Hansen, John Wiley & Sons, 1998</ref><ref>Phased Array Antenna Handbook, 2nd Ed., by Robert Mailloux, Artech House, 2005</ref><ref>Phased Array Antennas by Arun K. Bhattacharyya, John Wiley & Sons, 2006</ref>

==Classification==

===Active versus passive=== Active phase shifters provide gain, while passive phase shifters are lossy. * Active: ** Applications: active electronically scanned array (AESA), passive electronically scanned array (PESA) ** Gain: The phase shifter amplifies while phase shifting ** Noise figure (NF) ** Reciprocity: not reciprocal * Passive: ** Applications: active electronically scanned array (AESA), passive electronically scanned array (PESA) ** Loss: the phase shifter attenuates while phase shifting ** NF: NF = loss ** Reciprocity: reciprocal

===Analog versus digital=== * Analog phase shifters provide a continuously variable phase shift or time delay.<ref>[http://www.herley.com/index.cfm?act=app_notes&notes=iqv_phaseshift Microwave Phase Shifter] {{Webarchive|url=https://web.archive.org/web/20030327163207/http://www.herley.com/index.cfm?act=app_notes&notes=iqv_phaseshift |date=2003-03-27 }} information from Herley General Microwave</ref> * Digital phase shifters provide a discrete set of phase shifts or time delays. Discretization leads to quantization errors. Digital phase shifters require parallel bus control. * '''Differential, single-ended or waveguide''': ** Differential transmission line: A differential transmission line is a balanced two-conductor transmission line in which the phase difference between currents is 180 degrees. The differential mode is less susceptible to common mode noise and cross talk. ** Antenna selection: dipole, tapered slot antenna (TSA) ** Examples: coplanar strip, slotline * Single-ended transmission line: A single-ended transmission line is a two-conductor transmission line in which one conductor is referenced to a common ground, the second conductor. The single-ended mode is more susceptible to common-mode noise and cross talk. ** Antenna selection: double folded slot (DFS), microstrip, monopole ** Examples: CPW, microstrip, stripline * Waveguide ** Antenna selection: waveguide, horn ===Frequency band=== ===One-conductor or dielectric transmission line versus two-conductor transmission line=== * One-conductor or dielectric transmission line (optical fibre, finline, waveguide): ** Modal ** No TEM or quasi-TEM mode, not TTD or quasi-TTD ** Higher-order TE, TM, HE or HM modes are distorted * Two-conductor transmission line (CPW, microstrip, slotline, stripline): ** Differential or single-ended ** TEM or quasi-TEM mode is TTD or quasi-TTD * '''Phase shifters versus TTD phase shifter''' ** A phase shifter provides an invariable phase shift with frequency, and is used for fixed-beam frequency-invariant pattern synthesis. ** A TTD phase shifter provides an invariable time delay with frequency, and is used for squint-free and ultra wideband (UWB) beam steering. ===Reciprocal versus non-reciprocal=== *Reciprocal: T/R *Non-reciprocal: T or R ===Technology=== * Non semi-conducting (ferrite, ferro-electric, RF MEMS, liquid crystal): ** Passive * Semi-conducting (RF CMOS, GaAs. SiGe, InP, GaN or Sb): ** Active: BJT or FET transistor based MMICs, RFICs or optical ICs ** Passive: PIN diode based hybrids

===Design=== * Loaded-line: ** Distortion: *** Distorted if lumped *** Undistorted and TTD if distributed * Reflect-type: ** Applications: reflect arrays (S<sub>11</sub> phase shifters) ** Distortion: *** Distorted if S<sub>21</sub> phase shifter, because of 3&nbsp;dB coupler *** Undistorted and TTD if S<sub>11</sub> phase shifter * Switched-network ** Network: *** High-pass or low-pass *** <math>\pi</math> or T ** Distortion: *** Undistorted if the left-handed high-pass sections cancel out the distortion of the right-handed low-pass sections * Switched-line ** Applications: UWB beam steering ** Distortion: undistorted and TTD * Vector summing

==Figures of merit==

* Number of effective bits, if digital [bit] * Biasing: current-driven, high-voltage electrostatic [mA, V] * DC power consumption [mW] * Distortion: group velocity dispersion (GVD) [ps<sup>2</sup>/nm] * Gain [dB] if active, loss [dB] if passive * Linearity: IP3, P1dB [dBm] * Phase shift / noise figure [°/dB] (phase shifter) or time delay / noise figure [ps/dB] (TTD phase shifter) * Power handling [mW, dBm] * Reliability [cycles, MTBF] * Size [mm<sup>2</sup>] * Switching time [ns]

==References==

{{reflist}}

==External links== *[https://www.microwaves101.com/encyclopedias/phase-shifters "Phase Shifters"], Microwaves101.com *[https://web.archive.org/web/20030327163207/http://www.herley.com/index.cfm?act=app_notes&notes=iqv_phaseshift Microwave Phase Shifter] information from Herley General Microwave *[http://www.activefrance.com/Antennas/Phase_Shifter8.pdf] A low cost electro-mechanical phase shifter design, including a brief summary of solid state methods @ www.activefrance.com{{deadlink|date=July 2019}}

{{DEFAULTSORT:Phase Shift Module}} Category:Radar Category:Microwave technology