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<title>Reflective array antenna</title>

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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Reflective array antenna</span></span>

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<p>In <a href="Telecommunications" title="Telecommunications">telecommunications</a> and <a href="Radar" title="Radar">radar</a>, a <b>reflective array antenna</b> is a class of <a href="Directional_antenna" title="Directional antenna">directive</a> <a href="Antenna_(electronics)" class="mw-redirect" title="Antenna (electronics)">antennas</a> in which multiple <a href="Driven_element" class="mw-redirect" title="Driven element">driven elements</a> are mounted in front of a flat surface designed to reflect the <a href="Radio_waves" class="mw-redirect" title="Radio waves">radio waves</a> in a desired direction. They are a type of <a href="Array_antenna" class="mw-redirect" title="Array antenna">array antenna</a>. They are often used in the <a href="Very_high_frequency" title="Very high frequency">VHF</a> and <a href="Ultra_high_frequency" title="Ultra high frequency">UHF</a> frequency bands. VHF examples are generally large and resemble a highway <a href="Billboard" title="Billboard">billboard</a>, so they are sometimes called <b>billboard antennas</b>. Other names are <b>bedspring array</b><sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> and <b>bowtie array</b> depending on the type of elements making up the antenna. The <a href="Curtain_array" title="Curtain array">curtain array</a> is a larger version used by <a href="Shortwave" class="mw-redirect" title="Shortwave">shortwave</a> radio broadcasting stations.

</p><p>Reflective array antennas usually have a number of identical driven elements, fed <a href="In_phase" class="mw-redirect" title="In phase">in phase</a>, in front of a flat, electrically large <a href="Reflector_(antenna)" title="Reflector (antenna)">reflecting surface</a> to produce a <a href="Directional_antenna" title="Directional antenna">unidirectional</a> beam of radio waves, increasing <a href="Antenna_gain" class="mw-redirect" title="Antenna gain">antenna gain</a> and reducing <a href="Radiation" title="Radiation">radiation</a> in unwanted directions. The larger the number of elements used, the higher the gain; the narrower the beam is and the smaller the <a href="Sidelobe" class="mw-redirect" title="Sidelobe">sidelobes</a> are. The individual elements are most commonly <a href="Half_wave_dipole" class="mw-redirect" title="Half wave dipole">half wave dipoles</a>, although they sometimes contain <a href="Parasitic_element" class="mw-redirect" title="Parasitic element">parasitic elements</a> as well as driven elements. The reflector may be a metal sheet or more commonly a wire screen. A metal screen reflects radio waves as well as a solid metal sheet as long as the holes in the screen are smaller than about one-tenth of a wavelength, so screens are often used to reduce weight and wind loads on the antenna. They usually consist of a grill of parallel wires or rods, oriented parallel to the axis of the dipole elements.

</p><p>The driven elements are fed by a network of <a href="Transmission_line" title="Transmission line">transmission lines</a>, which divide the power from the RF source equally between the elements. This often has the circuit geometry of a tree structure.

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<div class="mw-heading mw-heading2"><h2 id="Basic_concepts">Basic concepts</h2></div>

<div class="mw-heading mw-heading3"><h3 id="Radio_signals">Radio signals</h3></div>

<p>When a radio signal passes a conductor, it <a href="Electromagnetic_induction" title="Electromagnetic induction">induces an electrical current</a> in it. Since the radio signal fills space, and the conductor has a finite size, the induced currents add up or cancel out as they move along the conductor. A basic goal of antenna design is to make the currents add up to a maximum at the point where the energy is tapped off. To do this, the antenna elements are sized in relation to the wavelength of the radio signal, with the aim of setting up <a href="Standing_wave" title="Standing wave">standing waves</a> of current that are maximized at the feed point.

</p><p>This means that an antenna designed to receive a particular wavelength has a natural size. To improve reception, one cannot simply make the antenna larger; this will improve the amount of signal intercepted by the antenna, which is largely a function of area, but will lower the efficiency of the reception (at a given wavelength). Thus, in order to improve reception, antenna designers often use multiple elements, combining them together so their signals add up. These are known as <i><a href="Antenna_array_(electromagnetic)" class="mw-redirect" title="Antenna array (electromagnetic)">antenna arrays</a></i>.

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<div class="mw-heading mw-heading3"><h3 id="Array_phasing">Array phasing</h3></div>

<p>In order for the signals to add together, they need to arrive <a href="Phase_(waves)" title="Phase (waves)">in-phase</a>. Consider two <a href="Dipole_antenna" title="Dipole antenna">dipole antennas</a> placed in a line end-to-end, or <i>collinear</i>. If the resulting array is pointed directly at the source signal, both dipoles will see the same instantaneous signal, and thus their reception will be in-phase. However, if one were to rotate the antenna so it was at an angle to the signal, the extra path from the signal to the more distant dipole means it receives the signal slightly out of phase. When the two signals are then added up, they no longer strictly reinforce each other, and the output drops. This makes the array more sensitive horizontally, while stacking the dipoles in parallel narrows the pattern vertically. This allows the designer to tailor the reception pattern, and thus the <a href="Antenna_gain" class="mw-redirect" title="Antenna gain">gain</a>, by moving the elements about.

</p><p>If the antenna is properly aligned with the signal, at any given instant in time, all of the elements in an array will receive the same signal and be in-phase. However, the output from each element has to be gathered up at a single feed point, and as the signals travel across the antenna to that point, their phase is changing. In a two-element array this is not a problem because the feed point can be placed between them; any phase shift taking place in the transmission lines is equal for both elements. However, if one extends this to a four-element array, this approach no longer works, as the signal from the outer pair has to travel further and will thus be at a different phase than the inner pair when it reaches the center. To ensure that they all arrive with the same phase, it is common to see additional transmission wire inserted in the signal path, or for the transmission line to be crossed over to reverse the phase if the difference is greater than <style data-mw-deduplicate="TemplateStyles:r1154941027">

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</style><span class="frac"><span class="num">1</span>⁄<span class="den">2</span></span> a wavelength.

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<div class="mw-heading mw-heading3"><h3 id="Reflectors">Reflectors</h3></div>

<p>The gain can be further improved through the addition of a <i>reflector</i>. Generally any conductor in a flat sheet will act in a mirror-like fashion for radio signals, but this also holds true for non-continuous surfaces as long as the gaps between the conductors are less than about <span class="frac"><span class="num">1</span>⁄<span class="den">10</span></span> of the target wavelength.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> This means that wire mesh or even parallel wires or metal bars can be used, which is especially useful both for reducing the total amount of material as well as reducing wind loads.

</p><p>Due to the change in signal propagation direction on reflection, the signal undergoes a reversal of phase. In order for the reflector to add to the output signal, it has to reach the elements in-phase. Generally this would require the reflector to be placed at <span class="frac"><span class="num">1</span>⁄<span class="den">4</span></span> of a wavelength behind the elements, and this can be seen in many common reflector arrays like <a href="Television_antenna" title="Television antenna">television antennas</a>. However, there are a number of factors that can change this distance, and actual reflector positioning varies.

</p><p>Reflectors also have the advantage of reducing the signal received from the back of the antenna. Signals received from the rear and re-broadcast from the reflector have not undergone a change of phase, and do not add to the signal from the front. This greatly improves the <a href="Front-to-back_ratio" title="Front-to-back ratio">front-to-back ratio</a> of the antenna, making it more directional. This can be useful when a more directional signal is desired, or unwanted signals are present. There are cases when this is not desirable, and although reflectors are commonly seen in array antennas, they are not universal. For instance, while UHF television antennas often use an array of <a href="Bowtie_antenna" class="mw-redirect" title="Bowtie antenna">bowtie antennas</a> with a reflector, a bowtie array without a reflector is a relatively common design in the <a href="Microwave" title="Microwave">microwave</a> region.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading3"><h3 id="Gain_limits">Gain limits</h3></div>

<p>As more elements are added to an array, the <a href="Beamwidth" class="mw-redirect" title="Beamwidth">beamwidth</a> of the antenna's main lobe decreases, leading to an increase in gain. In theory there is no limit to this process. However, as the number of elements increases, the complexity of the required feed network that keeps the signals in-phase increases. Ultimately, the rising inherent losses in the feed network become greater than the additional gain achieved with more elements, limiting the maximum gain that can be achieved.

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<p>The gain of practical array antennas is limited to about 25–30 dB. Two half wave elements spaced a half wave apart and a quarter wave from a reflecting screen have been used as a standard gain antenna with about 9.8 dBi at its design frequency.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> Common 4-bay television antennas have gains around 10 to 12 dB,<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> and 8-bay designs might increase this to 12 to 16 dB.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> The 32-element <a href="SCR-270" title="SCR-270">SCR-270</a> had a gain around 19.8 dB.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> Some very large reflective arrays have been constructed, notably the Soviet <a href="Duga_radar" title="Duga radar">Duga radars</a> which are hundreds of meters (yards) across and contain hundreds of elements. <i>Active</i> array antennas, in which groups of elements are driven by separate RF amplifiers, can have much higher gain, but are prohibitively expensive.

</p><p>Since the 1980s, versions for use at <a href="Microwave" title="Microwave">microwave</a> frequencies have been made with <a href="Patch_antenna" title="Patch antenna">patch antenna</a> elements mounted in front of a metal surface.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading2"><h2 id="Radiation_pattern_and_beam_steering">Radiation pattern and beam steering</h2></div>

<p>When driven in phase, the <a href="Radiation_pattern" title="Radiation pattern">radiation pattern</a> of the reflective array is a single <a href="Main_lobe" title="Main lobe">main lobe</a> perpendicular to the plane of the antenna, plus several <a href="Sidelobe" class="mw-redirect" title="Sidelobe">sidelobes</a> at equal angles to either side. The more elements used, the narrower the main lobe and the less power is radiated in the sidelobes.

</p><p>The main lobe of the antenna can be steered electronically within a limited angle by <a href="Phase_shift" class="mw-redirect" title="Phase shift">phase shifting</a> the drive signals applied to the individual elements. Each antenna element is fed through a <a href="Phase_shifter" class="mw-redirect" title="Phase shifter">phase shifter</a> which can be controlled digitally, delaying each signal by a successive amount. This causes the wavefronts created by the superposition of the individual elements to be at an angle to the plane of the antenna. Antennas that use this technique are called <a href="Phased_array" title="Phased array">phased arrays</a> and often used in modern radar systems.

</p><p>Another option for steering the beam is mounting the entire antenna structure on a pivoting platform and rotating it mechanically.

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<ul><li><a href="Mars_Cube_One" title="Mars Cube One">Mars Cube One</a> (2018 spacecraft design with Reflective array antenna)</li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><cite id="CITEREFUS_Navy1998" class="citation book cs1 cs1-prop-long-vol">US Navy (September 1998). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=41vUCgAAQBAJ&q=%22bedspring+array%22+antenna"><i>NAVEDTRA 14183 - Navy Electricity and Electronics Training Series</i></a>. Vol. Module 11 - Microwave principles. Lulu Press. p. 236. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>1-329-66770-0</bdi>.</cite></span>

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<li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://radiojove.gsfc.nasa.gov/class/educ/radio/tran-rec/exerc/iono.htm">"The Effects of Earth's Upper Atmosphere on Radio Signals"</a>. <i>NASA</i>.</cite></span>

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<li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><cite id="CITEREFRaut2014" class="citation book cs1">Raut, S. (July 2014). "Wideband printed bowtie array for spectrum monitoring". <i>2014 IEEE Antennas and Propagation Society International Symposium (APSURSI)</i>. pp. <span class="nowrap">235–</span>236. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FAPS.2014.6904449">10.1109/APS.2014.6904449</a>. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-1-4799-3540-6</bdi>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:42085218">42085218</a>.</cite></span>

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<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.schwarzbeck.de/en/antennas/standard-gain-antennas.html">"Standard Gain Antennas"</a>.</cite></span>

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<li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.channelmaster.com/Digital_HDTV_Outdoor_TV_Antenna_p/cm-4221hd.htm">"ULTRAtenna 60"</a>. <i>Channel Master</i>.</cite></span>

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<li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.channelmaster.com/CM_4228HD_p/cm-4228hd.htm">"EXTREMEtenna 80"</a>. <i>Channel Master</i>.</cite></span>

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<li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><cite id="CITEREFBurrows2013" class="citation book cs1">Burrows, Chas. R. (2013-10-22). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=k7g4BQAAQBAJ&pg=PA460"><i>Radio Wave Propagation</i></a>. Academic Press. p. 460. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-1-4832-5854-6</bdi>.</cite></span>

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<li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><cite id="CITEREFHuang" class="citation book cs1">Huang, john. <i>Reflectarray antennas</i>.</cite></span>

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</ol></div>

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</style><span class="citation FS1037C MS188"><span class="noviewer" typeof="mw:File"><span></span></span> This article incorporates <a href="Copyright_status_of_works_by_the_federal_government_of_the_United_States" title="Copyright status of works by the federal government of the United States">public domain material</a> from <cite class="citation cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20220122224547/https://www.its.bldrdoc.gov/fs-1037/fs-1037c.htm"><i>Federal Standard 1037C</i></a>. <a href="General_Services_Administration" title="General Services Administration">General Services Administration</a>. Archived from <a rel="nofollow" class="external text" href="https://www.its.bldrdoc.gov/fs-1037/fs-1037c.htm">the original</a> on 2022-01-22.</cite> (in support of <a href="MIL-STD-188" title="MIL-STD-188">MIL-STD-188</a>).</span>

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</style><div class="thumb tmulti tleft"><div class="thumbinner multiimageinner" style="width:766px;max-width:766px"><div class="trow"><div class="tsingle" style="width:247px;max-width:247px"><div class="thumbimage"><span typeof="mw:File"></span></div><div class="thumbcaption">A modern form of reflective array is the "bow tie" <a href="Ultrahigh_frequency" class="mw-redirect" title="Ultrahigh frequency">UHF</a> <a href="Television_antenna" title="Television antenna">television antenna</a>. This example has two dipole driven elements in front of a grill reflector. The "bow-tie" dipoles, consisting of two V-shaped elements, have a larger bandwidth than ordinary dipoles, allowing the antenna to cover the wide UHF television band. This example is installed for reception of vertically polarized TV transmissions.</div></div><div class="tsingle" style="width:232px;max-width:232px"><div class="thumbimage"><span typeof="mw:File"></span></div><div class="thumbcaption">Enormous reflective array antenna of the <a href="Duga_radar" title="Duga radar">Duga</a> or "Steel Yard" <a href="Over_the_horizon_radar" class="mw-redirect" title="Over the horizon radar">over-the-horizon</a> (OTH) radar system, Chernobyl, Ukraine, part of the Soviet early-warning network. It transmits at frequencies between 7 and 19 MHz. The pairs of cylindrical cages at right are the <a href="Half_wave_dipole" class="mw-redirect" title="Half wave dipole">half wave dipole</a> driven elements. Behind them is a reflector screen of horizontal wires, just visible in center.</div></div><div class="tsingle" style="width:281px;max-width:281px"><div class="thumbimage"><span typeof="mw:File"></span></div><div class="thumbcaption">An <a href="ALLISS" title="ALLISS">ALLISS</a> antenna, a modular type of <a href="Curtain_array" title="Curtain array">curtain array</a> used by international <a href="Shortwave" class="mw-redirect" title="Shortwave">shortwave</a> stations for broadcasting to distant areas by <a href="Skywave" title="Skywave">skywave</a>.</div></div></div></div></div>

<div class="thumb tmulti tleft"><div class="thumbinner multiimageinner" style="width:694px;max-width:694px"><div class="trow"><div class="tsingle" style="width:187px;max-width:187px"><div class="thumbimage"><span typeof="mw:File"></span></div><div class="thumbcaption">VHF reflective array TV antenna from 1954. The driven elements are folded dipoles, the two long ones cover 54–88 MHz the 4 short ones 174–216 MHz.</div></div><div class="tsingle" style="width:113px;max-width:113px"><div class="thumbimage"><span typeof="mw:File"></span></div><div class="thumbcaption">"Panel array" VHF TV broadcasting antenna. This type is widely used for UHF today</div></div><div class="tsingle" style="width:114px;max-width:114px"><div class="thumbimage"><span typeof="mw:File"></span></div><div class="thumbcaption">"Bowtie" UHF TV antenna from 1954</div></div><div class="tsingle" style="width:272px;max-width:272px"><div class="thumbimage"><span typeof="mw:File"></span></div><div class="thumbcaption">Closeup of SCR-20 reflective array from the 1950s</div></div></div></div></div>

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</style><div id="Antenna_types153" style="font-size:114%;margin:0 4em"><a href="Antenna_(radio)" title="Antenna (radio)">Antenna</a> types</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Isotropy" title="Isotropy">Isotropic</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Isotropic_radiator" title="Isotropic radiator">Isotropic radiator</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Omnidirectional_antenna" title="Omnidirectional antenna">Omnidirectional</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Batwing_antenna" title="Batwing antenna">Batwing antenna</a></li>

<li><a href="Biconical_antenna" title="Biconical antenna">Biconical antenna</a></li>

<li><a href="Cage_aerial" title="Cage aerial">Cage aerial</a></li>

<li><a href="Coaxial_antenna" title="Coaxial antenna">Coaxial antenna</a></li>

<li><a href="Crossed_field_antenna" title="Crossed field antenna">Crossed field antenna</a></li>

<li><a href="Dielectric_resonator_antenna" title="Dielectric resonator antenna">Dielectric resonator antenna</a></li>

<li><a href="Dipole_antenna" title="Dipole antenna">Dipole antenna</a></li>

<li><a href="Discone_antenna" title="Discone antenna">Discone antenna</a></li>

<li><a href="Folded_unipole_antenna" title="Folded unipole antenna">Folded unipole antenna</a></li>

<li><a href="Charles_Samuel_Franklin#High-efficiency_Medium-wave_Transmitting_Antenna" title="Charles Samuel Franklin">Franklin antenna</a></li>

<li><a href="Whip_antenna#Gain_and_radiation_resistance" title="Whip antenna">Ground-plane antenna</a></li>

<li><a href="G5RV_antenna" title="G5RV antenna">G5RV antenna</a></li>

<li><a href="Halo_antenna" title="Halo antenna">Halo antenna</a></li>

<li><a href="Helical_antenna" title="Helical antenna">Helical antenna</a></li>

<li><a href="Inverted-F_antenna" title="Inverted-F antenna">Inverted-F antenna</a></li>

<li><a href="Inverted_vee_antenna" title="Inverted vee antenna">Inverted vee antenna</a></li>

<li><a href="J-pole_antenna" title="J-pole antenna">J-pole antenna</a></li>

<li><a href="Mast_radiator" title="Mast radiator">Mast radiator</a></li>

<li><a href="Monopole_antenna" title="Monopole antenna">Monopole antenna</a></li>

<li><a href="Random_wire_antenna" title="Random wire antenna">Random wire antenna</a></li>

<li><a href="Rubber_ducky_antenna" title="Rubber ducky antenna">Rubber ducky antenna</a></li>

<li><a href="Sloper_antenna" title="Sloper antenna">Sloper antenna</a></li>

<li><a href="Turnstile_antenna" title="Turnstile antenna">Turnstile antenna</a></li>

<li><a href="T2FD_antenna" title="T2FD antenna">T2FD antenna</a></li>

<li><a href="T-antenna" title="T-antenna">T-antenna</a></li>

<li><a href="Umbrella_antenna" title="Umbrella antenna">Umbrella antenna</a></li>

<li><a href="Whip_antenna" title="Whip antenna">Whip antenna</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Directional_antenna" title="Directional antenna">Directional</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Adcock_antenna" title="Adcock antenna">Adcock antenna</a></li>

<li><a href="Near_vertical_incidence_skywave#The_AS-2259_Antenna" title="Near vertical incidence skywave">AS-2259 Antenna</a></li>

<li><a href="AWX_antenna" title="AWX antenna">AWX antenna</a></li>

<li><a href="Beverage_antenna" title="Beverage antenna">Beverage antenna</a></li>

<li><a href="Cantenna" title="Cantenna">Cantenna</a></li>

<li><a href="Cassegrain_antenna" title="Cassegrain antenna">Cassegrain antenna</a></li>

<li><a href="Choke_ring_antenna" title="Choke ring antenna">Choke ring antenna</a></li>

<li><a href="Collinear_antenna_array" title="Collinear antenna array">Collinear antenna array</a></li>

<li><a href="Conformal_antenna" title="Conformal antenna">Conformal antenna</a></li>

<li><a href="Corner_reflector_antenna" title="Corner reflector antenna">Corner reflector antenna</a></li>

<li><a href="Curtain_array" title="Curtain array">Curtain array</a></li>

<li><a href="Folded_inverted_conformal_antenna" title="Folded inverted conformal antenna">Folded inverted conformal antenna</a></li>

<li><a href="Fractal_antenna" title="Fractal antenna">Fractal antenna</a></li>

<li><a href="Gizmotchy" title="Gizmotchy">Gizmotchy</a></li>

<li><a href="Helical_antenna" title="Helical antenna">Helical antenna</a></li>

<li><a href="Horn_antenna" title="Horn antenna">Horn antenna</a></li>

<li><a href="Log-periodic_antenna" title="Log-periodic antenna">Log-periodic antenna</a></li>

<li><a href="Loop_antenna" title="Loop antenna">Loop antenna</a></li>

<li><a href="Microstrip_antenna" title="Microstrip antenna">Microstrip antenna</a></li>

<li><a href="Moxon_antenna" title="Moxon antenna">Moxon antenna</a></li>

<li><a href="Offset_dish_antenna" title="Offset dish antenna">Offset dish antenna</a></li>

<li><a href="Patch_antenna" title="Patch antenna">Patch antenna</a></li>

<li><a href="Phased_array" title="Phased array">Phased array</a></li>

<li><a href="Planar_array" class="mw-redirect" title="Planar array">Planar array</a></li>

<li><a href="Parabolic_antenna" title="Parabolic antenna">Parabolic antenna</a></li>

<li><a href="Plasma_antenna" title="Plasma antenna">Plasma antenna</a></li>

<li><a href="Quad_antenna" title="Quad antenna">Quad antenna</a></li>

<li><a href="Regenerative_loop_antenna" title="Regenerative loop antenna">Regenerative loop antenna</a></li>

<li><a href="Rhombic_antenna" title="Rhombic antenna">Rhombic antenna</a></li>

<li><a href="Sector_antenna" title="Sector antenna">Sector antenna</a></li>

<li><a href="Short_backfire_antenna" title="Short backfire antenna">Short backfire antenna</a></li>

<li><a href="Slot_antenna" title="Slot antenna">Slot antenna</a></li>

<li><a href="Sterba_antenna" title="Sterba antenna">Sterba antenna</a></li>

<li><a href="Vivaldi_antenna" title="Vivaldi antenna">Vivaldi antenna</a></li>

<li><a href="WokFi" title="WokFi">WokFi</a></li>

<li><a href="Yagi%E2%80%93Uda_antenna" title="Yagi–Uda antenna">Yagi–Uda antenna</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Application-specific</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="ALLISS" title="ALLISS">ALLISS</a></li>

<li><a href="Corner_reflector" title="Corner reflector">Corner reflector</a> (passive)</li>

<li><a href="Evolved_antenna" title="Evolved antenna">Evolved antenna</a></li>

<li><a href="Ground_dipole" title="Ground dipole">Ground dipole</a></li>

<li><a href="Reconfigurable_antenna" title="Reconfigurable antenna">Reconfigurable antenna</a></li>

<li><a href="Rectenna" title="Rectenna">Rectenna</a></li>

<li><a href="Reference_antenna" title="Reference antenna">Reference antenna</a></li>

<li><a href="Spiral_antenna" title="Spiral antenna">Spiral antenna</a></li>

<li><a href="Circularly_disposed_antenna_array" title="Circularly disposed antenna array">Circularly disposed antenna array</a></li>

<li><a href="Television_antenna" title="Television antenna">Television antenna</a></li></ul>

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This article is issued from <a class="external text" title="Last edited on 2025-06-25" href="https://en.wikipedia.org/wiki/?title=Reflective_array_antenna&oldid=1297271531">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

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