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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58 views

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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1answer
186 views

What are these dishes looking at?

In this CSA video CSA Astronaut Chris Hadfield describes the attitude control of the ISS and its importance for things like communication with Earth. At 00:30 here ...
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2k views

Angular distance between two satellites given azimuth and elevation angles for each?

If the look angles for a pair of satellites are $Az_1, El_1$ and $Az_2, El_2$, what would be the angular separation between them? An associated problem is how do we determine whether and when the two ...
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1answer
47 views

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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1answer
136 views

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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1answer
139 views

How does this large, flat antenna made from overlapping circles at Australia's Carnarvon Space Tracking Center work?

@Fred's comment links to the Australian Broadcasting Corporation's How the Apollo 11 Moon landing was achieved with the vital help of Carnarvon Tracking Station which links to their Carnarvon space ...
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1answer
88 views

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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1answer
63 views

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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1answer
210 views

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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1answer
204 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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89 views

Calibration of Antennae in satellite and in ground station [closed]

How to orient the ground station antenna and that of the satellite just after the launch?
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81 views

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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120 views

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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30 views

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?