Letters to the Editor • Space Travel and Exploration
GROUND STATIONS ARE JUST THE BEGINNING: THE SATNOGS STORY
I thought you'd enjoy this. open source satellite technology...
http://hackaday.com/2015/02/19/ground-stations-are-just-the-beginning-the-s atnogs-story/
GROUND STATIONS ARE JUST THE BEGINNING: THE SATNOGS STORY
When you think of satellites, you may think of the Space Shuttle extending
its robot arm with a huge piece of high-tech equipment waiting to pirouette
into orbit. This misconception is similar to picturing huge mainframes when
thinking about computers. The future (and arguably even the present)
reality of satellites is smaller, cheaper, and more prolific. This future
is also an "open" one if the Libre Space Foundation has anything to say
about it.
This group that plans to make satellite communications available to anyone
started out as a build at a hackerspace. One good idea, a shared set of
skills and experience, and a little bit of time led them to accomplish
amazing things. We are, of course, talking about the Grand Prize winners of
the 2014 Hackaday Prize. The SatNOGS team built a working satellite ground
station and laid the foundation for a data-sharing network to connect to
it. But even this description can be a bit daunting, so come with me to
learn what this is all about, and how it matters to you.
Crowd-Sourcing Satellite Ground Stations
"BoiseSatelliteDish" by Kencf0618 - CC BY-SA 3.0 via Wikimedia Commons
Satellite ground stations have been around as long as satellites have. It's
simply the antenna that communicates with satellites in space. The
traditional model is a huge dish, sometimes enclosed in a white dome.
There are several things to consider. First, a single ground station can
only stay in contact with a satellite if it is in geostationary orbit
(meaning the satellite is always above the same point on the earth). Dishes
pointing at these satellites are in near-constant communication with these
satellites. Want to get some time on this thing? Fat chance!
Secondly, satellites which are not locked in synchronous orbit are only in
contact with a single ground station for a small portion of each pass.
Eventually the planet gets in the way and you need a ground station on a
different part of the globe to communicate with it while you are in
blackout.
Internals of a SatNOGS ground station.
The SatNOGS project seeks to address both of the issues just mentioned. It
starts with the hardware; an Open Design which can be built at a minimum of
cost using readily available tools and a reasonable skillset. Bootstrapping
your own receiver is one way to guarantee your access to a ground station.
But if you're also willing to share some of that time with others you
unlock the solution to the second problem.
The SatNOGS project allows multiple ground stations to synchronize their
data and to schedule time on each instance of the hardware around the
world. A ground station must point at the right place at the right time for
any given satellite. The platform design accounts for this by sending
scheduling data back to each ground station which will automatically adjust
its aim to line up with the next satellite capture request.
Building the network is key. As more people build and deploy their own
hardware, everyone gets a bigger piece of the satellite data as it is
collected.
This is Bigger than SatNOGS: Libre Space Foundation
>From the description above we're sure you agree that this has the potential
to be much more than a project between a few friends. This is a movement.
The SatNOGS team came to this realization early on and conceived of an
organization to help illuminate the path. The Libre Space Foundation was
formed with the idea that all of satellite communications should have an
Open model. This means the satellites themselves, the ground stations, and
the data.
We already mentioned the Grand Prize, which was of course a trip into
space. We were really hoping that we'd see a hacker sign up for such an
adventure, but we're thrilled with the alternative. The SatNOGS team went
with the cash option of $196,418 and chose to invest it in the Libre Space
Foundation (LSF). This is a great jump-start but the LSF needs more than
just cash to succeed. They need people to adopt and further their vision.
CubeSats
[Arko's] satellite project Cubex via Hackaday.io
Those smaller, cheaper satellites that we mentioned before come from many
different players. They are often known as CubeSats and the common
form-factor is 10cm on each side. Universities have been building and
launching these for some time now. It's a great engineering challenge, to
be certain, but it's also a way to conduct experiments in near-zero
gravity.
Private industry has been in on the action as well. Planet Labs has
launched what they call "flocks" of these small satellites which work
together to form something of a line-scanner for the planet. The system
images the entire earth once every 24 hours.
Already there are proofs of concept that all point to personal satellites.
That's right, you can own a satellite. Just like the two previous examples;
built it small, and launch it as extra cargo. We saw a very successful
crowd funding campaign just a couple of years ago on the topic. And our own
Hackaday.io has numerous satellites, warranting a roundup of them all.
The Satellite Data
What kind of data can you get from these satellites? It's easy to assume
that all of this is encrypted and proprietary but that's simply not the
case. Sure, media and communications satellites are not going to dump the
latest episode of Game of Thrones into your home-built ground station. But
there are a lot of satellites that are broadcasting useful data in the
open.
To name one very interesting source, the National Oceanic and Atmospheric
Administration (NOAA) has a collection of satellites monitoring weather and
transmitting the data back to earth. Recording these transmissions is a
trick we've seen many times over the years.
One that we've seen less often is grabbing data sets from research
satellites like those launched by University programs. Getting your hands
on the data without waiting for the researchers' publication means more
opportunities for peer-review and better access for educational purposes.
The potential is also there to form your own communications networks. Right
now SatNOGS hardware is a receive-only unit. But the software stack is
ready for transmit and receive. This will that the DVB-T dongle be swapped
for something with a transmitter, and more than likely will call for
licensure in most areas (for example, an amateur radio license) but these
are not large hurdles to cross. As mentioned, the LSF has hopes of
developing Open Hardware and Open Source Software designs for satellites.
Imagine your own data network. In Space. Now that is a brave new world.
Here's How You Can Help
We like to dream big and it excites us that the LSF is doing just that. But
they need your help.
Version 3 of the SatNOGS ground station is in development and they can use
experts in all areas to help. Most notably, RF design to help improve
communications, as well as mechanical design to ensure the build will stand
up to time and weather. Check out the SatNOGS community for more on getting
involved directly.
Don't have the skills to build these yourself? Don't worry, just spreading
the word is a big way to help. Give a talk at your local Hackerspace, or
just pester all of your neighbors. It's space, everyone wants to hear about
that, right?