Questions tagged [radio-communication]

Using radio wavelengths to communicate between multiple spacecraft or between a spacecraft and the Earth.

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100 views

What does it take to upgrade a radio antenna to receive from the surface of Mars?

All the discussion about receiving transmissions from Mars rovers got me thinking, what determines the capability of a radio antenna, and what goes into adding the capability of listening to a Mars ...
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Even small countries have a few ~30 m diameter parabolic antennas but nobody reported signals coming from the landers on Mars. How is it possible? [duplicate]

The parabolic antennas with diameters of ~30 meters are all over the world. Even small countries have them. However, nobody, except DSN or other entities controlled by the US government, has ever ...
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Can anything at Mars speak 900 MHz ZigBee besides Ingenuity helicopter and Perseverance rover?

Interest is piqued by What could be strong arguments against Ingenuity following Perseverance at a safe distance when the flight test program has been a success? Question: Can anything at Mars ...
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What's the most intense beam ever sent from Earth?

By a freak coincidence sensors on a passing alien ship a hundred light years away had picked up a faint artificial blip from Earth, thereby discovering our inhabited planet. But which blip was it? ...
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Why are minimum three artificial satellites required for radio-communication all around the Earth?

Artificial satellites orbiting the Earth have important applications for radio-communication around it. To avoid the blockage of radio-communication around the Earth, multiple satellites can be ...
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How long did the plasma blackouts of Perseverance's signals to MRO and direct-to-Earth last during its seven minutes of terror?

Congratulations to NASA JPL and the Perseverance Team and everyone else who participated and contributed in some way! Watching the live feed of the EDL seven minutes of terror I heard there was a ...
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Does SPICE function gftfov account for occultations?

I need to determine when an antenna on a spacecraft can see a ground station on Earth at particular epochs. I have generated all the necessary SPICE kernels necessary as well as using the NASA ...
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129 views

Does the Juno spacecraft have an “open signal, by design”?

The click-bate title'd Space News article China quietly used NASA’s Jupiter probe to test its deep space network contains the quoted material below. Everybody listens to everybody else's spacecraft's ...
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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 для ...
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What is a Beam Waveguide dish and why does the Deep Space Network use them?

NASA Spaceflight.com's Deep Space Network upgrades and new antennas increase vital communication capabilities says: NASA’s Deep Space Network, commonly referred to as the DSN, has welcomed a new dish,...
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First Ham Radio contact from space; what frequency, what kind of antenna, and how did they route the coax out the window?

From Phys.org's Earthlings and astronauts chat away, via ham radio: NASA astronaut Doug Wheelock was just a few weeks into his six-month mission at the space station when feelings of isolation began ...
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When our Moon is hiding Mars, is it possible to create a radio communication between Earth and Mars?

According to this link Mars is hiding behind the Moon ... It’s a twice-a-year occultation; like the eclipse When such situations happen, can we communicate with the Mars rovers, and in the future - ...
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How did Argentina, Namibia, and Pakistan help China monitor and communicate with Chang'e 5?

At the end of The Hill's article Chinese official unveils future moon mission plans including possible lunar base it says: The most recent Chang'e 5 probe was assisted by the European Space Agency, ...
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How will the closure of the Arecibo dish impact deep space communications?

Earlier today, the U.S. National Science Foundation announced that it is decommissioning the Arecibo radio telescope. The 305 meter dish is famous for the 1974 message for extra-terrestrial ...
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Hijacked space data, notable instances of recovering images or other goodies from someone else's space mission?

The original of this GIF was tweeted here and I've reconstructed it because I don't know how to post it here (How to show this particular tweeted (GIF?) in a question? - trouble downloading). These ...
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What is the bandwidth (in hertz) of the Voyager 2 radio receiver?

Does anybody know the bandwidth of the Voyager 2 radio receiver's front-end? I know that the current data rate of the receiver is of order tens of bits per second, and I have one estimate of 18 Hz. ...
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How many total hours had Arecibo transmitted a signal?

Update: Sadly, parts of the dish have collapsed, several cables have snapped, and the Arecibo radio telescope is now decommissioned and demolition has been recommended because it is now too unsafe to ...
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Why was Canberra able to listen to Voyager 2 but not talk to it?

The New York Times's When Voyager 2 Calls Home, Earth Soon Won’t Be Able to Answer explains that because Voyager 2's trajectory has taken it way below the ecliptic, of the three 70 meter dishes in the ...
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When, if ever, did deep space probes start using encryption?

What, if any, mechanisms prevent unauthorized commands? Asks what measures are taken for spacecraft, although the answer doesn't go much farther than pointing to the What would one need to do in order ...
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Is GNU Radio being used for any Deep Space Missions in development?

GNU Radio is an open source collection of code and tools to build various radio elements for a "Software Defined Radio" or a radio implemented with the help of an FPGA that is programmed to ...
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Can I transmit signals from a wristwatch to geostationary orbit?

In comments below this answer to the question Which satellites can hear emergency signals from Scott Kelley's watch? we are (or at least I am) trying to figure out definitively if a wristwatch can ...
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Problems receiving Iridium messages during the middle of the 'day' in the far North

I have some scientific instruments using Iridium modems for communication active at around or higher than 82°N. At the time of writing this message, we are in middle of August, i.e. the polar day ...
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Are NASA (and ESA?) deep space spacecraft now generally able to store and forward messages between themselves?

There are discussions under the current answer to Will Curiosity and the Mars 2020 rover be able to communicate with each other via a Mars orbiter? about the feasibility of MRO receiving a message ...
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China, UAE and US all sending missions to Mars in 2020 (Summer of L̶o̶v̶e Mars); how far apart are their frequencies?

Gizmodo's Second failure of ExoMars parachute test throws schedule in jeopardy says: ExoMars 2020 is due to launch during a narrow window open between July 25th to August 13th 2020, during which ...
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How is RF spectrum usage coordinated in Mars orbit?

As of 2016 there are multiple operational missions in orbit around Mars. There are possibly more non-operational missions in orbit around Mars, simply because we do not know the final fate of all ...
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Why is the operating temperature for the Voyagers' receiver noise calculation about 1550K?

In line 10 of Table 5.2 of DESCANSO IV - Voyager Telecommunications it shows a value of the uplink receiver noise spectral density of -166.7 dBm/Hz, which is 196.7 dBW/Hz which is 2.1E-20 Watts/Hz = $...
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From whence (what ground stations) do the world's major space agencies receive signals from their missions?

The ISRO web page Ground Segment says: SRO Telemetry Tracking and Command Network (ISTRAC) will be providing support of the TTC ground stations, communications network between ground stations and ...
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Interactions between rocket exhaust and radio communications?

Rocket exhaust is bright in visible light, we can still see through it but when there's hot, glowing soot it's so bright that we think it's opaque, but it's not. See answers to How does the camera ...
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Would adding satellites between Earth and Mars improve communications latency?

Would adding satellites along the path from Earth to Mars decrease the amount of time it takes to send and receive messages between them?
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IRIS Transceiver for LEO Missions?

My professor really wants to know if the IRIS transceiver, which flew on MarCo, will be used in LEO. In fact so much that he doesn't accept "no" for an answer. I have searched for an example but found ...
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Are and should satellites use wireless communication internally, rather than cables?

Some applications on Earth replace wires with radio communication, standard stuff like Bluetooth. It saves mass and maybe complexity. Is this done for intra-satellite communication and deep space ...
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Does Russian mission control still use the callsign “Zarya”, and how did that not conflict with the ISS module?

The Wikipedia page for the Salyut space station claims Initially, the space stations were to be named Zarya, the Russian word for 'Dawn'. However, as the launch of the first station in the ...
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Why not send Voyager 3 and 4 following up the paths taken by Voyager 1 and 2 to re-transmit signals of later as they fly away from Earth?

Voyager 1 and Voyager 2 spacecrafts are on their journey out of solar system. They collected so much of important data that helped us understand our solar system. As these spacecrafts moving out of ...
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What does “clearing of C-band spectrum” mean and why will it cost Intelsat a billion dollars?

From "Intelsat files for bankruptcy" One of the primary catalysts for restructuring the balance sheet now is Intelsat’s desire to participate in the accelerated clearing of C-band spectrum under ...
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Inter-satellite linking for satellite constellations?

All the existent satellite constellations and the proposed ones talk about inter-plane communications as a very challenging issue due to: High relative velocities between satellites Tracking control ...
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Curiosity / MRO UHF connection and weak signal modulation

In the case of MRO and Curiosity communications via UHF, an active feedback system was implemented in which Curiosity monitored the quality/SNR of the connection and commanded Curiosity to increase / ...
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Encryption in radio system

We know that radio waves are used in communication with rockets, space crafts and satellites. Now, radio system basically consists of transmitter and receiver. If there is frequency match between ...
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Why did Moon missions state their number in radio context?

I'm not sure if this still happens, so the question may be broader, but in the Apollo transcripts the astronauts would begin a call with something like "Houston, 13". I get that they may have been on ...
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UHF transceiver for cubesats network

I already asked things related to this topic. But this time I will try to divide it by points to make it more understandable. Features of my cubesats: Would have 8 cubesats 3U in Earth's orbit The ...
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Alternatives to the X-Band

is there any other band that can do something similar to what the x-band does? Any that require a smaller antenna and more electrical power?
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Could multimode (polymer) optical fiber Gigabit Ethernet be a better choice than WiFi inside future satellites?

In this answer the recent question Are and should satellites use wireless communication internally, rather than cables? it is stated that: This is actually an open research area and despite ...
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Which company provided communication equipment for Apollo missions in which Neil Armstrong was a part?

In July 1969, the Apollo mission transmitted Neil Armstrong’s first steps on the moon to millions around the world. Which famous company provided the entire communication equipment for the project?
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Why did Sputnik-1 transmit on both 20 and 40 MHz?

Wikipedia's Sputnik 1 and this answer to Why did Sputnik 1 have four antennas? say that Sputnik transmitted at both 20 and 40 MHz. Why two different frequencies? Why so far apart? It's worth noting ...
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What did Sputnik-1 sound like? Did it use multiple tones?

Radio transmissions from Sputnik-1 could be heard on short wave radios around the world. Questions: A carrier signal only would not be particularly audible to an AM radio listener, was it modulated ...
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How does SpaceX transmit the video feed from the first and second stage cameras back to Earth?

There appear to be at least 1 reasonably high-res (500+ px vertical res) live video stream being transmitted from both the SpaceX F9 first and upper stages all the way up into LEO throughout their ...
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What was the transmitting power of the Apollo astronauts' PLSS VHF radio transmitters?

I'm assuming many of you are familiar with Larry Baysinger. A radio amateur who independently detected and recorded the transmissions from the Apollo 11 EVA using a homemade antenna. Larry Baysinger ...
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What “gap” could have caused the Starliner instructions to be delayed?

The Starliner launch didn't go as planned today After being released by the rocket, Starliner was supposed to use its Orbital Maneuvering and Attitude Control engines to provide the thrust needed ...
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What are the main sources of radio noise & interference limiting deep space data rates and availability?

Let's call "radio" anything electromagnetic below 300 GHz (1 millimeter), unless there is a compelling reason to do otherwise. The question How well can Voyager 1 separate Earth signals from Solar ...
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Did New Horizons use its smaller medium-gain antenna for most/all downlinking of Pluto and Arrokoth flyby data?

Brian May's New Horizons video (below) was released at about the same time that the New Horizons spacecraft passed 2014 MU69 Arrokoth and includes a lot of technically meaningful graphics. One item ...
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Why have four parabolas on a ground-side array instead of just a single large one

An article on RT: Russia to stop ferrying US astronauts to ISS from April 2019, is accompanied by a photo of a ground-side radio array consisting of four separate parabolas merged into one pointable ...