Questions tagged [antenna]

Questions about devices which collect and couple electromagnetic signals (communications, radar or other electromagnetic measurements) directly between free space, and conductors (e.g. waveguides or other transmission lines).

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52 views

How exactly were the signals from quad dishes of Apollo Deep Space High-Gain Antenna or Russian B-529 processed for local control of tracking?

The images below (and their sources) show the quad dishes of the Apollo Deep Space High-Gain Antenna and the Russian B529 ground station tracking antenna. From NASA Technical Note TN D-6723 Apollo ...
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Which deep space spacecraft had main dish antennas that were perforated or made from mesh?

A long time ago I was considering asking why the dish antennas on some deep-space probes were perforated metal or mesh (presumably to save weight), while others were solid. I'm trying to finally ...
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Did any of Voyagers' receivers' front ends take advantage of the “cold of space” to lower noise?

Most of the Voyagers' electronics are kept warm by electrical heaters powered by their RTG's, and presumably protected by some amount of insulation from the "cold of space" which means loss of heat ...
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What antenna is this in an Apollo 15 LM photo?

The video Apollo 15 landing from PDI to Touchdown (found in Why did the Apollo 15 LM violently shake & raise dust after the contact probes touched the lunar surface?) seems to pan across a still ...
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How did Luna 3's pivoting antennas and ribbon antennas work?

This comment below this answer to How was it possible for the Apollo 11 to film and take pictures with such radiation? links to the svengrahn.pp.se post Luna 3 - the first view of the moon's far side. ...
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Did New Horizons use its smaller medium-gain antenna for most/all downlinking of Pluto and Ultima Thule flyby data?

Brian May's New Horizons video (below) was released at about the same time that the New Horizons spacecraft passed 2014 MU69 Ultima Thule and includes a lot of technically meaningful graphics. One ...
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How were the 100+ antennas around Telstar 1 and 2 configured?

Telstar 1 and 2 demonstrated routing of telephone, television and other communications types between continents. The Smithsonian Air and Space Museum pages below contain images of the satellites. ...
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How video projection screen is used in test of Europa Clipper's high gain antenna?

Phys.org's Europa Clipper high-gain antenna undergoes testing says: The full-scale prototype antenna, which at 10 feet (3 meters) tall is the same height as a standard basketball hoop, is in the ...
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How do these cubesats' whip antennas work?

This answer has identified the three 1U cubesats shown in the question, and links to Engineers Rule's Maya-1: The Philippines’ First CubeSat along with the video Animation of MAYA-1, The Philippines' ...
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Why do these satellite antennas look so weird? (strangely shaped with little white dots…)

The NASA Spaceflight article Arianespace press onward with dual-passenger Ariane 5 launch shows a photo of Intelsat 39 during testing. The dish reflectors are strangely shaped: rather than being ...
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Impact of having two antennas on link budget calculations

I'm working on link budget of a cubesat mission that needs to have two dipole antennas that are perpendicular to each other. I want to know if having two antennas affect the link budget? losses, and ...
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What kind of transmitters and antennas do the Lightsail-2 ground stations use?

The cubesat Lightsail-2 has been deployed and has communicated with ground stations. See The Planetary Society's LightSail 2 Healthy as Mission Team Continues Spacecraft Checkouts, where it says: ...
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How large of an antenna would you need to connect to the ISS's WiFi network from Earth?

Supposing I wanted to connect to the ISS's WiFi network from the ground, how large of an antenna would I need to do so, and what kind? Would they need to increase the power on their end or use a ...
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Was there a prototype for Solar Probe's hybrid Heat Shield/Antenna?

An early concept of the Solar Probe (reborn as Solar Probe Plus then Parker Solar Probe) used a parabolic antenna with a heat-resistant nadir facing side to double as a heat shield. While sourcing ...
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Will there be “Near Space” Ka-band allocations for TESS?

update: More information in Phys.org's news item TESS mission to discover new planets moves toward launch, including a video of the telescope array's final assembly. Also see GSFC's TESS page. The ...
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How does Deep Space Network's DSS-14 transmit radar and receive it at (almost) the same time? (monostatic radar)

@Hobbes' concise yet thorough answer to the question What are monostatic radar observations, and how will Deep Space Network's DSS-13 be used to observe asteroid 1999 WK4's flyby of Earth? tells us ...
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Could the Voyager spacecraft be spin-stabilized to keep their high gain antennas pointing towards the Sun (and therefore Earth)?

A suggestion has been made that the Voyagers may run out of propellant and so may not be able to maintain pointing near the Earth for communications. According to @BowlOfRed's answer: Although the ...
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When did deep-space probes start getting wrapped in germanium-coated film?

The NASA video Juno Engineering: Precision Matters shows the Juno spacecraft on what look like it might be a spin balance table after about 02:50 and there one can ...
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How does this fast-slewing dish track moving spacecraft?

Elon Musk's recent tweet shows a video clip of a modest-sized dish on fairly fast-slewing mount located: At SpaceX Boca Chica launch site in Texas In the question Why is the reflector on this ...
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Relation between beamwidths of E-plane and H-plane

Is there any relation between E-plane and H-plane beamwidths of an antenna when steering in azimuth and elevation directions?
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Why do GEO satellites need different types of antenna?

Why do GEO satellites like the one shown in the picture below need different types of antenna? Is there a reference library or website where we can get more information on different antenna types, ...
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How does the pattern on the MarCo cubesat's antenna boost data-transmission?

I was looking at a few posts that uhoh had made about the MarCo cubesat. One of the pictures was the one that I've posted below: The most I can gather from casual NASA articles is along the lines of: ...
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What is this combination tracking telescope and helical antenna pair? was it really used, and who is/was FlightLine?

I spotted the image below here which I found here (also seen here). Zooming in on this combination pair of telescope trackers and pair of RHCP and LHCP (right- and left-handed circular polarization) ...
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How do Inmarsat 5 F4's beams correspond to all of these antennas and feeds?

note: This is an old-style @uhoh question meaning that it is a bit on the long side. In this case I think it really needs to be since the question is a bit complex; I'm trying to understand how all ...
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Did NASA's Borg Collective-designed antennas work? Have similar designs ever been used in spacecraft beyond testing?

This interesting answer to the question Do antenna farms on spacecraft make any sense or are they purely aesthetic? in Worldbuilding SE links to the NASA Ames page 'Borg' Computer Collective Designs ...
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When scientific and engineering data are sent from space probes, are the signals repeated to minimize transmission error?

I would think that this would be the case. In any one transmission there will be a systematic error due to the fundamentals of the transmitter / receiver. Is there also a transient or stochastic error ...
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How do you calculate the lat and lon of a point on the earth using azimuth and elevation seen from a geostationary satellite?

I am given the longitude of a geostationary satellite and a pointing vector from the satellite in the form of azimuth and elevation angles looking from the satellite towards the earth (where zero ...
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What is the largest antenna deployed in space?

@Tristan's answer says: The satellites are classified, so details are speculative, but it is believed that the Magnum/Orion and Mentor SIGINT satellites have parabolic antennae around 100 m in ...
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Is OSIRIS-REx's high gain antenna nearly the same as TESS'? If so, why?

These two high gain antennas look very similar superficially, but are not identical. Is this a case of convergent design (a fancy kind of coincidence) or have they evolved from the same source, or ...
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What happened to the plan to build a DSN antenna array?

More than ten years ago there were plans to build large antenna arrays for DSN, about 400 antennas of 12m diameter. See these NASA papers 1, 2, 3, 4. What happened to these plans?
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What kind of ground-based radio astronomy is NASA's DSN used for? Who are the PIs?

I looked at DNS Now to check on Hayabusa-2 and compare to http://haya2now.jp/en.html and saw that DSS 34 in Canberra is currently in setup/teardown for Ground Based Radio Astronomy! In this status ...
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Are Hayabusa-2's high gain antenna disks electrically point-able?

Writing this answer I realized that Hayabusa-2 has two very similar looking circular flat disks that serve as it's high gain antennas. One is dedicated to X-band (7-8 GHz) and the other to Ka-band (32 ...
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191 views

How does this antenna work, with both a feed horn and hyperbolic secondary in front of the dish?

Scrolling through the Roscosmos twitter feed I saw this image of a dish antenna in a recent tweet. Google translate shows that the post says: Новый измерительный пункт будет построен на Сахалине ...
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Why were the antennas on the spherical surface of some early satellites spiral-shaped?

In the question What's the spiral pattern on this satellite? I show this image of a spiral-shaped pattern on the spherical surface of a (presumably) vintage satellite or model thereof. @OrganicMarble'...
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Function and nature of the RHC/LCH pair of cables to New Horizons's dish antenna secondary mirror?

Spaceflight 101's New Horizons Spacecraft Overview is full of interesting information and shows this RF Comm System Block Diagram. The thin (red) lines to the dish antenna area are coaxial cables and ...
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107 views

Need help identifying this (likely to be) phased array antenna used to track launches

I need help identifying the (what I believe to be) flat (and possibly phased) array antenna shown next to the tracking telescope in this photo, which can be found both here and here where the ...
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What are these antenna-like structures seen in Oleg Artemyev twitter video?

Russian Cosmonaut Oleg Artemyev's Sept 3, 2018 tweet has a narrated video of Earth from the ISS, at the time over the Nile river. The video is also in YouTube (below). At the bottom of the screen, ...
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What's the largest area dish antenna sent beyond the Earth-Moon system?

In the same vein as the question What's the largest aperture telescope sent beyond the Earth-Moon system?, I'd like to ask, what's the largest area antenna dish sent beyond the Earth-Moon system? If ...
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What is the Telescope Invariant Point?

I am working on an implementation of an SLR tool. At some points of the documentation of the CRD format the term telescope invariant point shows up. Apparently it's a point on an ILRS antenna system. ...
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How would the antenna on a spacecraft in GEO be provided an electrical ground?

I would like to understand better what specifications or guidelines address the electrical grounding/Earthing a parabolic reflector Antenna in GEO to minimize the potential difference with respect to ...
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What is this spinning object seen on a spacecraft above the ISS?

In the YouTube Trailer for the PBS program A Year in Space at 00:56 a small spinning object can be seen, attached to a spacecraft well above the ISS. I think the ...
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What were those motorized human-piloted platforms with helical antennas called (tracking launches)?

This interesting question got me started. I have these vignettes in my Apollo-era memory of antenna systems that tracked launches for telemetry. They had maybe four end-fire helical antennas pointing ...
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The appearance of TESS' dish seems to be evolving, what will be the final configuration?

The question Why is TESS' high gain antenna made of undulating BLACK fabric rather than metal? has had three bounties, and is probably the recipient of this sites longest answer. My personal pet ...
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What is the large circular device with a dozen concentric circles on Sentinel 3B?

The Spaceflight Now article Photos: Sentinel 3B satellite prepared for launch from Plesetsk Cosmodrome has of course lots of photos. One of them shows a dish antenna covered with shiny, metallized ...
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How does Curiosity know how to point and move it's high gain antenna in real time?

The Curiosity rover has a compact X-band high-gain antenna (HGA) that allows for low data rate communication directly with Earth, but is used mostly for higher data rates to spacecraft orbiting Mars, ...
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What is the function of this (apparently) fixed dish on the ISS?

I saw this image in Popular Science, one of the example photos from the book by astronaut/photographer/astrophotographer(?) Donald Pettit. It's beautiful and impressive not only from a color/...
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What is the purpose of the rotating dish antenna on the ISS

I just saw some footage of the ISS in which a dish antenna could be seen, constantly rotating. The dish looked more-or-less parabolic, meaning that it is presumably sending/receiving along a fairly ...
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568 views

What is Canted Turnstile Antenna System? What it its Applications?

There are not many sources I can read to know about this kind of Antenna and its Applications
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How to design a ground antenna for sending & receiving from a satellite?

Let's suppose there is a wifi router or a cell phone or similar transmitter in an orbit of 3000 km. How could one make a dish antenna to connect and receive the signal from that wifi router or cell ...
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How does SpaceX Falcon Heavy Starman live feed transmitter work?

I'm curious to find out answers to the following questions: Where is the antenna for the live feed transmitter of starman located in the payload? How is the transmitter being powered? Related to 2nd ...