Questions tagged [satellite]
Circuit design for satellites differs because of the space environment, which includes designating for vacuum, large temperature swings, and radiation tolerance. Satellite circuits should be able to handle latch ups and Single Event Upsets (SEU's) from radiation that ionizes silicon channels and recover from faults.
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energy flux density vs distance
I am looking for a formula for the figure given below. The Figure shows distribution of the energy flux density of electromagnetic radiation at a height of 2 m from the earth's surface in the area of ...
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Radiation tolerance of MCUs
I'm working on a cubesat project intended to operate in low earth orbit. We're considering a few different options for our flight computer, ranging from Raspberry Pi to something like STM32L476. ...
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Radius of footprint vs altitude: math equation
I want to compare footprint size/beam size of satellite and plot “radius of footprint vs. altitude” variation. ( my main reference( see above) is 3GPPTR38_821/Solutions for {NR} to support non-...
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How to compute a data rate "loss"?
I am studying 6G communication. There are a lot of publication about it, frequency, latency, BW and other KPIs.[1],[2]
Now one of the most popular research topics is an integration non-terrestrial ...
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How to compute propagation delay of satellite
In the table propagation delays of different satellite system are given. I want to reproduce the data of this table.
According to my understanding, propagation delay is
$$\tau =\frac{D}{V}, $$
where \$...
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What are the limitations of USB in aerospace (especially microsatellites)?
I have just joined a startup company that builds microsatellites. But I am quite new to the aerospace field.
I noticed that to connect components with the onboard computer we use many electrical ...
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How to compute link budget in a system with aero/space-borne integration
I am studying a system in 5G which are represented as a combination terrestrial and non-terrestrial network (including satellite segments or HAP/LAP) [5G NTN]
it is a unified terrestrial aerospace ...
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HAPs communication: What is a layer of a cell?
HAPs - High-altitude platform systems:
What a cell is, it is clear, but what is a layer of the cell ?
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Why this grounding scheme?
The NASA technical book about grounding in spacecraft (NASA-HDBK-4001) (I believe the question may be relevant for any other terrestrial application) mentions this grounding scheme for subsystems:
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How to choose a wrap (station) antenna for space application?
I am looking for my research project a wrap (station) antenna. It is assumed that the antenna works in space (lunar) environment. The total dose for my device is 30 – 50 krad. Gain 3-5 dBi. Frequency ...
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Is this how cable networking works? [closed]
I am studying about how cable networks transmit data to various TV channels on our TV screen. It is fascinating to see how they work.
After studying different articles online, I have made points as to ...
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Link budget: receive power > 0
I want to compute link budget in free space laser communication.
My input parameters: wave length 700 nm, transmitter aperture: 0,88/0,15/0,2 m, receiver aperture: 0,3/0,5/1
My results:
I have a ...
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Modulator in lasercom: from theory to practice
Hello everyone!
We are working on a realisation of an optical modulator and have a
doubt. Mr Noel Miller posted already a question, but it was suggested
this community. I will repost his question ...
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Output back off of a high power amplifier (HPA)
We are selling S-band HPAs for satcom applications.
A customer needs to obtain key RF characteristics of the S-Band HPA, specifically the wideband frequency response of carriers as a function of ...
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Why don't GPS satellites experience power outage more often than they should?
With the advent of smartphones I would believe that there's this huge exponential growth in number of GPS receivers around, and by now there should be an unaccountable number of devices on earth ...
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How does the 4th satellite in GPS know the time offset?
Going through the working of GPS technology, I came to know that at least 4 satellites must be visible to solve for the location with considerable accuracy. Going through most of the resources, I can ...
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Arduino : send data via satellite (or other solutions) without GSM [closed]
I'm a researcher. I'm looking to build a very tiny embedded system with low power consumption. I must send data from the desert and above the ocean. To do that I think that my single option is to use ...
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Where would be the best place to start looking for information on developing a bootloader using 2 microcontrollers for a CubeSat?
I am an engineering student who has just begun working on a CubeSat project for my design class. We are working on the OBC, specifically looking at developing a bootloader at this time. The OBC ...
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Help with calculating frequency offset
A 10 MHz TXCO is driving a receiver’s front end and has a frequency deviation of 10 ppm. It drives a direct downconversion RF front-end mixing the L5 frequency. What is the frequency offset at ...
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Does satellite radio use AM or FM or both? [closed]
Somehow, I cannot find an answer anywhere... I am guessing both...
Several actual satellites had FM in their names, so perhaps that is a clue, but I want to know for sure...
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How does being exposed to strong radiations effect nanosatellite electronics equipment?
I'm on paper designing a nanosatellite power system. The satellite would be orbiting in LEO. And I am wondering how and what type of radiation would affect its electronics. The system has a ...
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Typical rms values for random jitter in satellite communication
I'm trying to find typical values for random jitter in satellite communication and I'm not really finding any values in any documents. Most of the time I only find definitions for different jitter ...
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Is building a long range wifi antenna to connect to the up and coming starlink internet possible? [closed]
I want to try to convert a residential satellite dish into a long range wifi antenna to theoretically see if I can connect to the up & coming starlink internet that is being released in Canada and ...
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Antenna Array - Hundreds of elements forming thousands of beams - How?
How would an antenna array of 100 elements be able to form 5000+ simultaneous beams?
Or do I have it wrong, there would only be a maximum 100 beams from the 100 elements at any one time and those ...
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Troubleshooting NOAA double cross antenna
I've been trying to recive NOAA automatic picture transmission (APT) pictures for a year now.
I never got a picture with V-dipole, so I decided to build a double cross antenna. I used 75 ohm coax ...
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How do I move a motor to a desired angle using a motor encoder?
So I have this project, the goal is basically to be able to make a motor move to rotate a set of gears and move a panel attached to a hinge to a desired angle. I have a motor encoder attached to the ...
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How does satellite TV get through in rain?
How does satellite TV get through in rain? I read somewhere that satellites make use of KU band to transmit data, we have heavy rainfall in various times of the year but even during those times TV ...
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Satellite array antenna beamforming - basic intuition help
When you see a satellite coverage region on the earth, the array antennas form tens of circles (small coverages) in a large coverage. My question is whether all these small circle coverages exist at ...
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Does DiSEqC require a DC bias?
The DiSEqC (Di[gital] S[attelite] Eq[uipment] C[ontrol] specification (bus_spec.pdf within https://www.eutelsat.com/files/PDF/DiSEqC-documentation.zip) describes a tone-based serial data bus that can ...
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Radiofrequency exposure from portable (vehicle-mounted) satellite uplink antennas
I came across these broadcasting vans recently in London.
The antenna that's deployed I think is a Vislink Advent uplink antenna, similar to this model, designed to transmit to satellites for ...
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Do you really need a satellite dish to communicate with satellites?
I'm doing a project where I have ground sensors that detect seismic activity and report their GPS coordinates via APRS if seismic activity is detected. I'd like to do the APRS over satellite.
The ...
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Can anyone explain Phantom Power and, specifically, how it's used in satellite television systems?
Although I spent many years in the electrical field, I specialized in Electrical Metrology (a long time ago). Bearing this in mind, I really know very little about satellite television system theory.
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Source generator for Satellite Tuner input
I need to design a source generator for a TV factory. They want to automatize the functional tests by applying a test module to the TV's at the end of the production line. All the peripherals of the ...
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Current limiting solution for pocketqube satellite
A project I am working on requires a reliable current limiting solution for a pocketqube picosatellite.
Currently a Texas TPS2553 is being employed which will cut power once the limit is hit. We are ...
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