Questions tagged [communication-satellite]
Questions about satellites designed to aid in communications, such as phone, TV and Internet satellites.
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Satellites Orbital Parameters
I want to access satellites' orbital parameters like inclination, right ascension of ascending node and argument of perigee. Unfortunately, I haven't been able to find this information.
Is there a ...
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3answers
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Starlink vs 5G? [closed]
Who is better in terms of speed and network mainly. I know Starlink is not fully functional but I am considering the case when it will be fully functional.
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1answer
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“…extending the Starlink network using longer-range laser comms and relay satellites to reach Mars and Starships in-transit” (Musk & Shotwell)
I have it on good authority that SpaceX's Elon Musk and Gwynne Shotwell:
...have talked about extending the Starlink network using longer-range laser comms and relay satellites to reach Mars and ...
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1answer
60 views
S-Band transceiver schematics [closed]
I'm working on a cubesat, and I want to communicate in the S-Band, arround 2.4GHz. And I'm searching for schematics of a transceiver example with arround 35 dBm of output power. If any have a .pdf, ....
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Quantum technology for starship communications and landing on Mars
Based on practically proven Quantum-Entanglement principle, any entangled quantum switch in this universe can be flipped instantaneously from elsewhere. Can it be used to send information from far off ...
3
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0answers
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How will Amazon's constellation differentiate itself from SpaceX's and OneWeb's?
The New York Times' Amazon Satellites Add to Astronomers’ Worries About the Night Sky says:
Much of the attention on these strings of satellites has been placed on the prolific launches of SpaceX and ...
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0answers
33 views
What's happening with Laser Light Communications (company) now? What satellites will it communicate with?
The pair of Stack Exchange questions linked below are almost four years old. I still don't exactly understand how this will work, but here I'd like to ask if this company is still around and if it ...
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142 views
How much krypton is stored on a Starlink satellite?
How much krypton (fuel) is there for the krypton-powered ion thrusters on Starlink satellites and how long does it last?
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0answers
100 views
Once Starlink is fully deployed how many satellites will be visible at any given moment?
So the GPS system has 31 satellites in an orbit of 20,180Â km. Most of the time there are at least 3-4 satellites 'visible' (visible from a signal reception point of view) at any given moment.
The ...
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0answers
230 views
What is the average weight and price of a telecom satellite?
I found a source estimating the average weight of commercial communications satellites and then I think maybe there is more such data about price and launch price too.
And then my question is about ...
4
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1answer
194 views
After 21 years of silence how and by whom was OSCAR-7 first identified as functional?
This 2017 comment below an answer to What is the oldest artificial satellite still in use? says:
But it should be mentioned that AMSAT-OSCAR 7 was silent between 1981 and 2002 for 21 years. It was ...
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2answers
234 views
How a spy satellite eavesdrop on another satellite?
I recently read about Mentor-4 (also alled USA-202 or NRLO-26), a gigantic US spy satellite (operated by NRO and the CIA) with a possible dish radio antenna of 100 meters in diameter located in GEO. ...
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1answer
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How could RCA Satcom III have been completely lost? (Or was it?)
This answer to What “missing satellite” was part of the story of CNN's debut? quotes the 1981 UPI Article The RCA Satcom III-R commercial communications satellite, designed to... as follows:
The ...
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1answer
403 views
What “missing satellite” was part of the story of CNN's debut?
NPR's Tune In To 'Up All Night' For The Story Of Daniel Schorr And The Birth Of CNN includes the following about the beginnings of Cable News Network
On CNN's rocky debut:
There were so many ...
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1answer
104 views
How much did the cheapest communications satellite cost?
Satellite communication is becoming bigger and better, and I wanted to find out more.
2
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1answer
81 views
Could you theoretically launch your own satellite and transmit satellite phone signals to it?
This is a RF and Space question mix, and I am new here and didn’t know where else to ask, so I asked here! This is in the United States btw.
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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 ...
3
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1answer
144 views
Determine envelopes for the payloads?
I am a mechanical engineer who is trying to expand my domain knowledge in aerospace and am currently reading a book to increase my understanding of it. I am mostly interested in studying the design of ...
4
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0answers
43 views
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 / ...
2
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1answer
149 views
How to calculate azimuth and elevation angle between aircraft and GEO satellite (in aircraft coordinates)
Given a fixed ground station, it is known how to calculate the azimuth and elevation.
If changing it to an aircraft which is changing its data (location, altitude, angles) and working with same ...
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0answers
105 views
How did SpaceX's VisorSat work? How did the sunshade articulate to shade parts of Starlink satellite as it orbits the Earth?
CNET's Elon Musk wants SpaceX to launch the next generation of space telescopes says:
The billionaire entrepreneur said that "VisorSat" satellites equipped with a sunshade to block ...
4
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0answers
47 views
Any commercial communication satellite in GEO Orbit that supports 25 KW Power?
As I understand, EchosTAR-11, built by Space systems Loral, was the first 20KW Commercial satellite.
(Reference: Recent Successful satellite systems- Visions for future by D.K.Sachdev).
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1answer
66 views
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 ...
3
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1answer
104 views
How do I calculate what antenna I need for my cubesat?
If I want to make a communication satellite, like MarCO, what formulas do I need to calculate the perfect antenna? Is there a difference between the X-Band and the classic UHF? If the cubesat is ...
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0answers
92 views
Where can I find data on satellite orbits?
I'm an enthusiast who'd like access to satellite orbital data to simulate / plot trajectories of manmade satellites (of any kind) on my home computer. Where's the best place for me to find this kind ...
3
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1answer
130 views
Will Optical communications be possible between Columbus' Ka-band (COLKa) Terminal at the ISS and EDRS?
The BBC's British radio antenna to arrive at space station says:
The new fridge-sized terminal will route video, voice and data to the ground through satellites that are actually higher in the sky ...
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0answers
31 views
Which regulatory agencies involved in approving GMDSS providers are staffed with people from Inmarsat?
NASA Spaceflight's Iridium marks major milestone with maritime safety, breaks monopoly says:
Since its implementation, Inmarsat has held a monopoly over the GMDSS.
But that has now changed.
In May ...
3
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2answers
204 views
Why do orbits in the Iridium constellation have an inclination of 86.4°?
Wikipedia's Iridium_satellite constellation; In-orbit spares says that Iridium satellites have an inclination of 86.4°:
Significant orbital inclination changes are normally very fuel-intensive, but ...
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0answers
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How to see Iridium Flares (if possible) in 2020 and beyond?
On December 27th, 2019, Iridium 97 burned up in the atmosphere and there was a "#Flarewell" celebration. However, according to this website which seems to be VERY detailed, there are still 5 ...
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2answers
135 views
Can communication satellite carry payload other than it's own boards?
Can we attach payload to communication satellite and detach it in space after having gained a specific altitude? What is probability that it will fail?
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0answers
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Are the SpaceBEEs still “illegal” or did they eventually receive approval to operate?
This answer to the question Might ISRO's 2018-004 launch be at least a technical violation of the Outer Space Treaty by India? clarifies some of the actions taken against Swarm Technologies for ...
4
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1answer
205 views
Has FCC jurisdiction for all the world for SpaceX's Starlink position?
These days, you can read in the news that SpaceX requested FCC for permission to change the orbit of the Starlink satellites already in orbit.
Now... from my understanding, the Starlink satellites ...
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1answer
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Will Curiosity and the Mars 2020 rover be able to communicate with each other via a Mars orbiter?
Curiosity's UHF antenna on sol 2439
Could Curiosity and the Mars 2020 rover communicate with each other via the MRO orbiter ?
And would it have advantages ? (Like: " I just saw a meteorite, and it'...
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0answers
47 views
Satellite Launch Aprroval: what is the role of ITU, FCC, and other international standards / regulators?
Seeking confirmation for the following assumption:
Satellites used for non-communication applications (military surveillance, weather monitoring etc.) are launched without specific prior approval from ...
7
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1answer
238 views
How has the brightness of SpaceX's Starlink constellation changed since May?
Shortly after the launch, before full orientation of the solar panels and raising of the orbits, the Starlink satellites were surprisingly bright and easily seen with the naked eye.
Back then, I heard ...
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1answer
137 views
Point Ahead Angle Calculation between LEO-GEO Satellite (ISL Scenario)
So, I have got two reference TLE from 2 different Satellite in LEO-GEO, which are as follows: (1st TLE for LEO, 2nd TLE for GEO)
...
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Velocity Vector Transformation for Point Ahead Angle and Doppler Shift Calculation for Inter-Satellite Link
So, I have the Radial and Tangential Velocity Vector (like in Figure 1) and also the Cartesian coordinate of 3D velocity vector. For reference, you can see in this link. Where, $o_{dot}$ vector matrix ...
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2answers
319 views
Point Ahead Angle and Doppler Shift Frequency Changes Calculation with the tangential/radial velocity component for Inter-Satellite Link
While calculating the Point Ahead Angle we work with Tangential Velocity vector component and to calculate the Doppler shift i.e changes in frequencies, we work with Radial Velocity Vector component.
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Does Surrey Satellite's Pathfinder lunar communications relay have customers lined up, or is it “If you build it, they will come”?
After about 24:00 in the BBC podcast Do We Need More Space Stations? BBC reporter Marnie Chesterton talks with Charles Cranston, the project manager for lunar ...
3
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1answer
421 views
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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0answers
204 views
When did they stop routing long-distance phone calls through satellites? What was the maximum volume at its peak?
I have read that in the early 1960's Telstar 1 and 2 were the first satellites to route long distance telephone calls.
I seem to remember that long, long ago, long distance (overseas?) phone calls ...
2
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1answer
213 views
Understanding line of sight between two satellite with oblate Earth using “scaling k-component”
I have been doing some reading on accuracy of determining line-of-sight between two satellites give a WGS84 oblate earth. The paper Rapid Determination of Satellite Visibility Periods (Alfano, Negron ...
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2answers
167 views
How does a Hall effect ion thruster have a sea-level Isp of 800? Operates at 1 atmosphere?
Astronatix's SPT-100 lists the following:
Stechkin electric rocket engine. Used on Meteor and Gals satellites.
In Production. 1.35 kW Hall thruster.
Thrust variable 2 to 20 kgf.
Marketed in USA by ...
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0answers
56 views
How does a “hybrid orbital raising system” based on R-4D (N2O4/MMH) + SPT-100 (Hall effect) work exactly? (Intelsat 38 & 39)
Astronatix's Intelsat 39 lists the two engines
SPT-100 Stechkin 1.35 kW Hall thruster.
R-4D Marquardt N2O4/MMH rocket engine. 490 N.
Question: Why is this combination on Intelsat 39 called "hybrid" ...
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2answers
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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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1answer
48 views
Video standard used on Intelsat 1 (Early Bird)
I was watching a documentary on Intelsat 1 (also known as Early Bird) and some of the first live television sent over it.
Was there any particular video format or modulation used, special for the ...
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1answer
176 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 ...
7
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1answer
190 views
What is a “critical mass” equivalent of number of satellites on LEO that would initiate chain reaction of destruction if 2 of them collide?
If a satellite is destroyed and blown to multiple small pieces of debris, each one of these pieces has tiny probability of destroying another satellite, creating more debris which now will have even ...
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0answers
47 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?
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1answer
59 views
Data Rates and Radios with Satellites [closed]
I am new to using radios and was wondering why do data rates matter when you use a radio to pull info from somewhere else. Also what does it mean when a satellite sends a wide band signal. Thank you ...
