0
$\begingroup$

I am curious to know what can we do to improve the data rate in the space? I see that there are some noise sources in the Space that affect the signal quality between ground stations & deep space.

As I've read so far in various NASA and JPL pages, deep space data rate seem to be in the 500 to 32k bps range, or sometimes even lower, which will not be enough to transmit/receive critical information in the future as spacecraft carry more sophisticated instrumentation and optical and radar imaging as well as larger data buffers.

What are possible options for increasing deep space data rates in the future, in the presence of various sources of noise?

$\endgroup$
  • 1
    $\begingroup$ "I see some noise sources in the Space", where do you see them? Would you like to add the source of this information? $\endgroup$ – mike Apr 26 '17 at 6:31
  • $\begingroup$ Man made interference, cosmic, solar, and other external noise sources. $\endgroup$ – Pras4 Apr 26 '17 at 6:37
  • $\begingroup$ I've asked a separate question What are the sources of radio noise and interference that limit deep space data rates and availability?, but I think this one is more compelling! $\endgroup$ – uhoh Apr 26 '17 at 8:18
  • 1
    $\begingroup$ Using a stronger transmiiter in the spacecraft is one possibility, using a larger antenna dish for a smaller beam width is another. Both require additional mass for the spacecraft. But an extra large antenna dish should fit under the payload fairing of the rocket used for launch and the rocket should be able to lift the additional mass. More precison for the attitude control of the spacecraft is necessary when using a smaller beam width. $\endgroup$ – Uwe Apr 26 '17 at 9:30
  • $\begingroup$ In space.stackexchange.com/questions/9280/… there is an example: double the transmitter power and go from a 2m antenna to 10 m diameter would offer an increase of data rate by a factor of 50. But a 10 m antenna dish on a spacecraft would be really hard to acheive. $\endgroup$ – Uwe Apr 26 '17 at 14:20
4
$\begingroup$

Yes we have solutions:

  • Higher-power transmitter

  • More directional emitting antenna (by increasing the frequency for instance)

  • Larger receiving antenna

  • Less noisy electronics

  • Electronics with less signal loss

  • More efficient modulation (which may require playing on the bandwidth)

I suggest you look into what is called the link budget equation to find more about the topic:

http://www.radio-electronics.com/info/propagation/path-loss/link-budget-calculation-formula-equation.php

https://en.wikipedia.org/wiki/Link_budget

The link budget tells you what to improve for analog communications, for ditigal communications you need to combine it to a Eb/N0 calculation:

https://en.wikipedia.org/wiki/Eb/N0

$\endgroup$
  • 2
    $\begingroup$ See also What is a link budget, and how do I make one? on Amateur Radio. $\endgroup$ – a CVn Apr 26 '17 at 12:00
  • $\begingroup$ A better answer would be for you to explain link budget basics, then include the link for those who want to read more. What does "more efficient modulation" mean? What exactly is inefficient about modulation currently being used? What kind of "less noisy electronics" is available? Why was "more noisy electronics" used? This is a good outline of an answer, but it should be fleshed out a bit more. $\endgroup$ – uhoh Apr 26 '17 at 16:50
  • $\begingroup$ I think "more noisy electronics" was used because it was cheaper and easier to construct and build. $\endgroup$ – Uwe Apr 26 '17 at 20:20
  • $\begingroup$ @Uwe most of the time the instructions sent up to the spacecraft are short, and the valuable goodies are the much larger data sent back to Earth. In this case the electronics having the noise would be the front ends of the dishes in the Deep Space Network, and those should be at least state-of-the-art-ish. $\endgroup$ – uhoh Apr 27 '17 at 2:26
  • $\begingroup$ Related question about DSN cryogenic front-ends. $\endgroup$ – uhoh Apr 27 '17 at 3:13

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.