10 ms·

Receiving images of Earth from satellites with software defined radio

235 points by l00sed 6y ago

axegon_ 6y ago
This is incredibly cool!!! Kind of had a similar weekend RTL SDR project in the back of my mind for quite a while but like a lot of things lately, it's been a classic case of kicking the can. I really wish I could dig up some motivation from somewhere(in general, not just this).
- l00sed 6y ago
  It certainly takes time and dedication to go through the steps, but I'd recommend The Thought Emporium for getting started: https://youtu.be/cjClTnZ4Xh4 https://youtu.be/cjClTnZ4Xh4
jrockway 6y ago
Stealing? The NOAA satellites exist for you to receive the signals; the NOAA even offers a detailed guide on how to build a receiver: https://noaasis.noaa.gov/NOAASIS/pubs/Users_Guide-Building_Receive_Stations_March_2009.pdf https://noaasis.noaa.gov/NOAASIS/pubs/Users_Guide-Building_R... The introduction even reads like this art project: "Satellites provide us with a unique and long-sought after opportunity to look at Earth from space. These spacecraft now enable us to observe and measure the many forces of nature which converge on our planet. Mankind can now observe the global nature of the environmental factors which interact to form the complex systems we call Earth. From the unique vantage point of space, sophisticated environmental/weather satellites bring us information about cloud formations and movements, precipitation amounts, temperatures, ocean currents, sea surface temperatures, air and water pollutants, drought and floods, severe weather conditions, vegetation, insect infestations, ozone content of the atmosphere, volcano eruptions, and other factors that affect our daily lives. They have also provided us with less tangible aesthetic values which help shape attitudes about the environment of this planet. This global attitude is, perhaps, just as important as the hard data that the satellites provide." I was hoping that this was some security vulnerability that let you receive images from private satellites.
- globular-toast 6y ago
  Even if the satellites are private, it is intercepting, not stealing.
  - birdyrooster 6y ago
    Also (especially if it’s got sufficiently high resolution) it is almost certainly encrypted with Aes-256 or similar.
    - londons_explore 6y ago
      Early satellites, of which there may still be a few active, had analogue sensors and analogue modulation. Can't AES encrypt analogue... Sure, various analogue scrambling schemes are possible, but they degrade the signal and add a lot of risk to the mission so theres a good chance they weren't used.
  - gruez 6y ago
    Some call copyright infringement "stealing" as well. Also, "stealing" someone's idea.
    - deleted 6y ago
      [deleted]
    - kube-system 6y ago
      Works by the US government are generally in the public domain and not eligible for copyright.
  - mc32 6y ago
    Hmmm. When someone steals another person’s notes or homework, I guess it could be called interception, but really it’s taking someone else’s work who hasn’t volunteered to give it to you and stealing is more appropriate. Now, if it’s public, that’s different.
    - 6y ago
leetbulb 6y ago
This is surprisingly easy to do with some cheap hardware[0]. There is plenty of information if you just search something like "NOAA RTL-SDR." Building the antenna is the most labor intensive part, but still very easily done. I haven't personally, but it's on my to-do list for this summer. [0] https://www.rtl-sdr.com/rtl-sdr-tutorial-receiving-noaa-weather-satellite-images/ https://www.rtl-sdr.com/rtl-sdr-tutorial-receiving-noaa-weat...
- rbreve 6y ago
  Yes, there is also a Reddit https://www.reddit.com/r/RTLSDR/ https://www.reddit.com/r/RTLSDR/
- jcims 6y ago
  I would say it's one of those ruses where it's easy to get basic results, but you can spend (tens of) thousands of dollars and years of learning and refinement to achieve anything approximating error-free results. It's a lot of fun though. Diving into SDR really opens up a new dimension of reality to you and lays bare the magic that can happen when you are able to directly apply complex mathematical constructs to real data coming out of a wire attached to, well, nothign. I got a little obsessed with it actually and had to step away from it for a while lol.
  - leetbulb 6y ago
    > I got a little obsessed with it actually and had to step away from it for a while lol. Same here. I burnt a ton of time just scanning for voice communications and analyzing ADS-B. Once you start playing around in GNU Radio and decoding more exotic stuff, you really start going down the RF rabbit hole. It's an amazing hobby for learning about electronics.
    - looklookatme 6y ago
      > Once you start playing around in GNU Radio and decoding more exotic stuff Do you have any tips or resources on how to get to a competency level where you get to decode arbitrary digital signals you find from a scan? I've read through all the GNU Radio documentation, along with the examples on their wiki and have even written my own blocks but keep finding that opening a grc file that someone else authored, there will be a critical block I've never seen before (and likely, never see again) which hampers experimentation. As soon as I attempt to decode a real-life signal, it feels like I dove in too fast -- there's too many unknowns, since the end result is [presumably] not going to be a nice, human-readable string. However, occasionally, I find challenges like [1] which are great, since you have the expectation that the signal _can_ be decoded; it's just that I've found examples like these to be quite rare. [1] https://www.gnuradio.org/blog/2018-02-21-gnu-radio-challenge-21-feb-2018/ https://www.gnuradio.org/blog/2018-02-21-gnu-radio-challenge...
stjo 6y ago
+1 for cool project; -1 for baity title as jrockway said:I was hoping that this was some security vulnerability that let you receive images from private satellites
- YayamiOmate 6y ago
  It still would not be stealing. I believe copying information from a commuication channel without autorization is called eavesdropping.
jbj 6y ago
You can also look into receiving weather forecast from the sky: https://forums.othernet.is/t/wiki-pages-for-the-othernet-dreamcatcher/5314 https://forums.othernet.is/t/wiki-pages-for-the-othernet-dre...
ethbro 6y ago
Also, "How not to optimize a webpage for HN." (Said with loving snark, as a former architecture student and knowing exactly why all the bells and formatting whistles were thrown in)
cushychicken 6y ago
Can't hack the dense, overly-arty prose.
- l00sed 6y ago
  Haha I do apologize for my writing style. Trying to work on that.
praveen9920 6y ago
This is interesting data. Are there any online services which stream this data over internet? AWS has an offering called Ground station. Can we use it to get same data? Anyone worked on it before? What kind of license apply to this satellite data? Can we use it for commercial purposes?
- Spooky23 6y ago
  Work product of the US government is in the public domain.
  - l00sed 6y ago
    Something I'm not sure of is whether or not I could legally sell these images, but as others have noted it's really "intercepting" signals rather than thieving. With an antenna and a raspberry pi, however, it certainly feels like a dangerous or exciting thing to be able to "hear" these signals.
    - Spooky23 6y ago
      You absolutely can, by design they are open to all. Major businesses are basically built on this data. So much so that nasty players like Accuweather want to limit access to public research and shut down weather.gov so that they can more readily monetize it.
- ynniv 6y ago
  Look for "Full Disc" at https://www.star.nesdis.noaa.gov/GOES/ https://www.star.nesdis.noaa.gov/GOES/
annoyingnoob 6y ago
Connection timeout. Seems that someone is 'stealing' your bandwidth.
- ASalazarMX 6y ago
  "At the end, Daniel Tompkins revealed that the readers of Hacker News were tricked into doing the image heist themselves. Brilliant."
arethuza 6y ago
During the Falklands War the Norwegians gave the UK a constant stream of images obtained from Soviet spy satellites that gave very good information on the position of the Argentinian Navy.
- tomato2juice 6y ago
  > images obtained from Soviet spy satellites How did they obtain them? Were they not encrypted?
  - arethuza 6y ago
    Sigint means - it is mentioned in the book GCHQ by Richard Aldrich.
tomato2juice 6y ago
I wouldn't call this stealing? Maybe "catching"? I've been following a related subreddit on this topic that might be useful to the hackers here: https://www.reddit.com/r/RTLSDR/ https://www.reddit.com/r/RTLSDR/
zwirbl 6y ago
Hug of Death? Couldn't find it in archive, so google cache it is https://webcache.googleusercontent.com/search?q=cache:https://l-o-o-s-e-d.net/signs-of-life https://webcache.googleusercontent.com/search?q=cache:https:... Though I haven't read the article yet
- encom 6y ago
  https://archive.ph/o9YC3 https://archive.ph/o9YC3
williesleg 6y ago
I just see a group of bored chinese girls. Where's the ethnicity diversity?
jonpurdy 6y ago
Somewhat related. For those who are new to SDRs, you can easily view airplane altitude, heading, speed, and other stats of passing aircraft with a cheap SDR. Aircraft transmit this using ADS-B and it's totally open and unencrypted. FlightAware (among other services) work by aggregating data from users around the world. You can even get a free premium subscription to their service by contributing. Easiest way is to use a Raspberry Pi, install their software (much easier now than back in 2013!), and you're good to go!
- mysterydip 6y ago
  I've said this before, but the first time I hooked up an RTL-SDR and tuned it to 1090 and saw live air traffic, I was awestruck. Sure the same info was available on flightaware, but something was special about being able to retrieve it myself.
- tverbeure 6y ago
  For those who are interested in submitting airplane data to the non-commercial ADSB-Exchange project, here are my extensive installation instructions: https://tomverbeure.github.io/2019/05/11/ADSB-Exchange-Feeder.html https://tomverbeure.github.io/2019/05/11/ADSB-Exchange-Feede....
- joncrane 6y ago
  Also note that Flightradar allows rich/famous people to pay to have their airplanes omitted from the display on the website.
jungletime 6y ago
Are any of those images of earth and space released to public domain, since NASA is a government agency? Especially video. I would like to use a clip for Youtube.
adwi 6y ago
A few posters have mentioned this being accessible with inexpensive hardware. Any tips on how someone starts getting into SDR stuff?
- throwaway3neu94 6y ago
  Buy this https://www.rtl-sdr.com/buy-rtl-sdr-dvb-t-dongles/ https://www.rtl-sdr.com/buy-rtl-sdr-dvb-t-dongles/ (even available on Amazon) Use gqrx to listen to the radio, public services / air traffic (if legal where you are. Great fun at airshows), ham radio operators etc https://gqrx.dk/download https://gqrx.dk/download - requires minimal knowledge to get started (select device, put in frequency, mode (AM or FM) and that's it. Just play). Great time:benefit ratio so far. There's an excellent video series focusing on SDRs at https://greatscottgadgets.com/sdr/ https://greatscottgadgets.com/sdr/ Then use gnuradio to build your own receiver from predefined blocks. Start with above cheap receive only SDR, but when you want to transmit, buy a HackRF. You do need a ham radio license to transmit. It's not hard (not even highschool level math). Even if you don't do the license, have a look at the materials linked at https://blog.hamstudy.org/links/ https://blog.hamstudy.org/links/ , specifically the linked book (free PDF or paid printed). The fundamentals are excellent and it picks you up where most people are (high school math skills, no idea about RF). If you speak German, the best resource is https://www.darc.de/der-club/referate/ajw/darc-online-lehrgang/ https://www.darc.de/der-club/referate/ajw/darc-online-lehrga... (also available as printed book) At that point you should have a better idea where to go, and even enough background to read "real" books like http://www.dspguide.com/ http://www.dspguide.com/ (the math is harder of course). DSP is what SDR is all about in the end. But also other radio related books, like the ARRL antenna book. (There are alternatives to everything of course, but with above recommendations you will not go wrong.)
  - dbhattar 6y ago
    Not sure why you would create a throwaway account to post this invaluable information.
    - dewey 6y ago
dekhn 6y ago
it's not stealing if they broadcast it unencrypted.
- preinheimer 6y ago
  It's interesting that somehow doing math to something sent to your house unsolicited would make it stealing. I'm not trying to argue with you, I just think it's a weird place to end up legally.
  - dekhn 6y ago
    The way I think about it is: it's generally accepted that news reporters can go through the trash you throw in a garbage bin and leave on the street. If you want to protect your privacy, shred your trash or otherwise deny physical access to reporters. The burden is on the transmitter to protect their asset and if they don't, they're negligent.
mhh__ 6y ago
Anyone interested in how SDR works/is implemented: the book "Software defined radio for engineers" is the only book I've come across that combines DSP and SDR in the right ratios (Proakis's DSP book is bad if you want to build things straight away)
jcun4128 6y ago
Man that's awesome... crazy how your brain is "zoomed in" to your daily life/forget zoom out on this rock in nothingness like a film of bacteria.
dghughes 6y ago
As a young teen in the early 80s I read about a project that used an FM radio, a printer, and a bit of code to detect meteoroids. When the meteoroid became a meteor it gave off a frequency in the FM range. I liked programming but wasn't good at it and didn't understand what I needed. I wasn't sure if my Atari 600XL was suitable for the project but I do believe the code was BASIC which the 600XL could run. And I didn't have a printer which at the time was like owning a unicorn.
aasasd 6y ago
So, if people say here that plenty of folks receive satellite imagery, are there projects to assemble a complete map of the planet and have it continually updated? As in, you know, a satellite view for OSM.
- aasasd 6y ago
  Though, if this imagery is the same as what's on https://rammb-slider.cira.colostate.edu https://rammb-slider.cira.colostate.edu — then its resolution is apparently on the level of ‘I can see mountains’.
enginoor 6y ago
I feel that GOES satellite imagery is a hidden gem, I'm surprised more people aren't working with it. The imagery is available at https://www.star.nesdis.noaa.gov/GOES/ https://www.star.nesdis.noaa.gov/GOES/ but is better explored at https://rammb-slider.cira.colostate.edu/ https://rammb-slider.cira.colostate.edu/ I have personally built a Twitter bot to collect and animate imagery throughout the day. I have it running for two locations currently. Continental US: https://twitter.com/satellite_CONUS https://twitter.com/satellite_CONUS NorthEast US: https://twitter.com/satellite_NE https://twitter.com/satellite_NE It's amazing to see storm formation visually.
- l00sed 6y ago
  Very cool!
- gavin_gee 6y ago
  github link to source? would live to build one for PNW
- Yhippa 6y ago
  That is very cool, thank you. I just sat there and stared at it and had a Pale Blue Dot moment. This thing is so beautiful and here we are fighting about everything.
amelius 6y ago
Who do we have to thank for not encrypting this data? PS: Aren't these images available on the web anyway? Well, if not, perhaps this project could change that.
7kay 6y ago
The title first suggested that the article is about a security vulnerability of a satellite. The DoD actually held a CTF recently focused on the security of space systems. Information is on https://www.hackasat.com/ https://www.hackasat.com/ I'm looking forward to the public release of the exercises from the qualifying round which will be on June 19.

235 points by l00sed 6y ago

This is incredibly cool!!! Kind of had a similar weekend RTL SDR project in the back of my mind for quite a while but like a lot of things lately, it's been a classic case of kicking the can. I really wish I could dig up some motivation from somewhere(in general, not just this).

l00sed 6y ago
It certainly takes time and dedication to go through the steps, but I'd recommend The Thought Emporium for getting started: https://youtu.be/cjClTnZ4Xh4 https://youtu.be/cjClTnZ4Xh4

jrockway 6y ago

Stealing? The NOAA satellites exist for you to receive the signals; the NOAA even offers a detailed guide on how to build a receiver: https://noaasis.noaa.gov/NOAASIS/pubs/Users_Guide-Building_Receive_Stations_March_2009.pdf https://noaasis.noaa.gov/NOAASIS/pubs/Users_Guide-Building_R... The introduction even reads like this art project: "Satellites provide us with a unique and long-sought after opportunity to look at Earth from space. These spacecraft now enable us to observe and measure the many forces of nature which converge on our planet. Mankind can now observe the global nature of the environmental factors which interact to form the complex systems we call Earth. From the unique vantage point of space, sophisticated environmental/weather satellites bring us information about cloud formations and movements, precipitation amounts, temperatures, ocean currents, sea surface temperatures, air and water pollutants, drought and floods, severe weather conditions, vegetation, insect infestations, ozone content of the atmosphere, volcano eruptions, and other factors that affect our daily lives. They have also provided us with less tangible aesthetic values which help shape attitudes about the environment of this planet. This global attitude is, perhaps, just as important as the hard data that the satellites provide." I was hoping that this was some security vulnerability that let you receive images from private satellites.

globular-toast 6y ago
Even if the satellites are private, it is intercepting, not stealing.
- birdyrooster 6y ago
  Also (especially if it’s got sufficiently high resolution) it is almost certainly encrypted with Aes-256 or similar.
  - londons_explore 6y ago
    Early satellites, of which there may still be a few active, had analogue sensors and analogue modulation. Can't AES encrypt analogue... Sure, various analogue scrambling schemes are possible, but they degrade the signal and add a lot of risk to the mission so theres a good chance they weren't used.
- gruez 6y ago
  Some call copyright infringement "stealing" as well. Also, "stealing" someone's idea.
  - deleted 6y ago
    [deleted]
  - kube-system 6y ago
    Works by the US government are generally in the public domain and not eligible for copyright.
- mc32 6y ago
  Hmmm. When someone steals another person’s notes or homework, I guess it could be called interception, but really it’s taking someone else’s work who hasn’t volunteered to give it to you and stealing is more appropriate. Now, if it’s public, that’s different.
  - 6y ago

leetbulb 6y ago

This is surprisingly easy to do with some cheap hardware[0]. There is plenty of information if you just search something like "NOAA RTL-SDR." Building the antenna is the most labor intensive part, but still very easily done. I haven't personally, but it's on my to-do list for this summer. [0] https://www.rtl-sdr.com/rtl-sdr-tutorial-receiving-noaa-weather-satellite-images/ https://www.rtl-sdr.com/rtl-sdr-tutorial-receiving-noaa-weat...

rbreve 6y ago
Yes, there is also a Reddit https://www.reddit.com/r/RTLSDR/ https://www.reddit.com/r/RTLSDR/
jcims 6y ago
I would say it's one of those ruses where it's easy to get basic results, but you can spend (tens of) thousands of dollars and years of learning and refinement to achieve anything approximating error-free results. It's a lot of fun though. Diving into SDR really opens up a new dimension of reality to you and lays bare the magic that can happen when you are able to directly apply complex mathematical constructs to real data coming out of a wire attached to, well, nothign. I got a little obsessed with it actually and had to step away from it for a while lol.
- leetbulb 6y ago
  > I got a little obsessed with it actually and had to step away from it for a while lol. Same here. I burnt a ton of time just scanning for voice communications and analyzing ADS-B. Once you start playing around in GNU Radio and decoding more exotic stuff, you really start going down the RF rabbit hole. It's an amazing hobby for learning about electronics.
  - looklookatme 6y ago
    > Once you start playing around in GNU Radio and decoding more exotic stuff Do you have any tips or resources on how to get to a competency level where you get to decode arbitrary digital signals you find from a scan? I've read through all the GNU Radio documentation, along with the examples on their wiki and have even written my own blocks but keep finding that opening a grc file that someone else authored, there will be a critical block I've never seen before (and likely, never see again) which hampers experimentation. As soon as I attempt to decode a real-life signal, it feels like I dove in too fast -- there's too many unknowns, since the end result is [presumably] not going to be a nice, human-readable string. However, occasionally, I find challenges like [1] which are great, since you have the expectation that the signal _can_ be decoded; it's just that I've found examples like these to be quite rare. [1] https://www.gnuradio.org/blog/2018-02-21-gnu-radio-challenge-21-feb-2018/ https://www.gnuradio.org/blog/2018-02-21-gnu-radio-challenge...

stjo 6y ago

+1 for cool project; -1 for baity title as jrockway said:I was hoping that this was some security vulnerability that let you receive images from private satellites

YayamiOmate 6y ago
It still would not be stealing. I believe copying information from a commuication channel without autorization is called eavesdropping.

jbj 6y ago

You can also look into receiving weather forecast from the sky: https://forums.othernet.is/t/wiki-pages-for-the-othernet-dreamcatcher/5314 https://forums.othernet.is/t/wiki-pages-for-the-othernet-dre...

ethbro 6y ago

Also, "How not to optimize a webpage for HN." (Said with loving snark, as a former architecture student and knowing exactly why all the bells and formatting whistles were thrown in)

cushychicken 6y ago

Can't hack the dense, overly-arty prose.

l00sed 6y ago
Haha I do apologize for my writing style. Trying to work on that.

praveen9920 6y ago

This is interesting data. Are there any online services which stream this data over internet? AWS has an offering called Ground station. Can we use it to get same data? Anyone worked on it before? What kind of license apply to this satellite data? Can we use it for commercial purposes?

Spooky23 6y ago
Work product of the US government is in the public domain.
- l00sed 6y ago
  Something I'm not sure of is whether or not I could legally sell these images, but as others have noted it's really "intercepting" signals rather than thieving. With an antenna and a raspberry pi, however, it certainly feels like a dangerous or exciting thing to be able to "hear" these signals.
  - Spooky23 6y ago
    You absolutely can, by design they are open to all. Major businesses are basically built on this data. So much so that nasty players like Accuweather want to limit access to public research and shut down weather.gov so that they can more readily monetize it.
ynniv 6y ago
Look for "Full Disc" at https://www.star.nesdis.noaa.gov/GOES/ https://www.star.nesdis.noaa.gov/GOES/

annoyingnoob 6y ago

Connection timeout. Seems that someone is 'stealing' your bandwidth.

ASalazarMX 6y ago
"At the end, Daniel Tompkins revealed that the readers of Hacker News were tricked into doing the image heist themselves. Brilliant."

arethuza 6y ago

During the Falklands War the Norwegians gave the UK a constant stream of images obtained from Soviet spy satellites that gave very good information on the position of the Argentinian Navy.

tomato2juice 6y ago
> images obtained from Soviet spy satellites How did they obtain them? Were they not encrypted?
- arethuza 6y ago
  Sigint means - it is mentioned in the book GCHQ by Richard Aldrich.

tomato2juice 6y ago

I wouldn't call this stealing? Maybe "catching"? I've been following a related subreddit on this topic that might be useful to the hackers here: https://www.reddit.com/r/RTLSDR/ https://www.reddit.com/r/RTLSDR/

zwirbl 6y ago

Hug of Death? Couldn't find it in archive, so google cache it is https://webcache.googleusercontent.com/search?q=cache:https://l-o-o-s-e-d.net/signs-of-life https://webcache.googleusercontent.com/search?q=cache:https:... Though I haven't read the article yet

encom 6y ago
https://archive.ph/o9YC3 https://archive.ph/o9YC3

williesleg 6y ago

I just see a group of bored chinese girls. Where's the ethnicity diversity?

jonpurdy 6y ago

Somewhat related. For those who are new to SDRs, you can easily view airplane altitude, heading, speed, and other stats of passing aircraft with a cheap SDR. Aircraft transmit this using ADS-B and it's totally open and unencrypted. FlightAware (among other services) work by aggregating data from users around the world. You can even get a free premium subscription to their service by contributing. Easiest way is to use a Raspberry Pi, install their software (much easier now than back in 2013!), and you're good to go!

mysterydip 6y ago
I've said this before, but the first time I hooked up an RTL-SDR and tuned it to 1090 and saw live air traffic, I was awestruck. Sure the same info was available on flightaware, but something was special about being able to retrieve it myself.
tverbeure 6y ago
For those who are interested in submitting airplane data to the non-commercial ADSB-Exchange project, here are my extensive installation instructions: https://tomverbeure.github.io/2019/05/11/ADSB-Exchange-Feeder.html https://tomverbeure.github.io/2019/05/11/ADSB-Exchange-Feede....
joncrane 6y ago
Also note that Flightradar allows rich/famous people to pay to have their airplanes omitted from the display on the website.

jungletime 6y ago

Are any of those images of earth and space released to public domain, since NASA is a government agency? Especially video. I would like to use a clip for Youtube.

adwi 6y ago

A few posters have mentioned this being accessible with inexpensive hardware. Any tips on how someone starts getting into SDR stuff?

throwaway3neu94 6y ago
Buy this https://www.rtl-sdr.com/buy-rtl-sdr-dvb-t-dongles/ https://www.rtl-sdr.com/buy-rtl-sdr-dvb-t-dongles/ (even available on Amazon) Use gqrx to listen to the radio, public services / air traffic (if legal where you are. Great fun at airshows), ham radio operators etc https://gqrx.dk/download https://gqrx.dk/download - requires minimal knowledge to get started (select device, put in frequency, mode (AM or FM) and that's it. Just play). Great time:benefit ratio so far. There's an excellent video series focusing on SDRs at https://greatscottgadgets.com/sdr/ https://greatscottgadgets.com/sdr/ Then use gnuradio to build your own receiver from predefined blocks. Start with above cheap receive only SDR, but when you want to transmit, buy a HackRF. You do need a ham radio license to transmit. It's not hard (not even highschool level math). Even if you don't do the license, have a look at the materials linked at https://blog.hamstudy.org/links/ https://blog.hamstudy.org/links/ , specifically the linked book (free PDF or paid printed). The fundamentals are excellent and it picks you up where most people are (high school math skills, no idea about RF). If you speak German, the best resource is https://www.darc.de/der-club/referate/ajw/darc-online-lehrgang/ https://www.darc.de/der-club/referate/ajw/darc-online-lehrga... (also available as printed book) At that point you should have a better idea where to go, and even enough background to read "real" books like http://www.dspguide.com/ http://www.dspguide.com/ (the math is harder of course). DSP is what SDR is all about in the end. But also other radio related books, like the ARRL antenna book. (There are alternatives to everything of course, but with above recommendations you will not go wrong.)
- dbhattar 6y ago
  Not sure why you would create a throwaway account to post this invaluable information.
  - dewey 6y ago

dekhn 6y ago

it's not stealing if they broadcast it unencrypted.

preinheimer 6y ago
It's interesting that somehow doing math to something sent to your house unsolicited would make it stealing. I'm not trying to argue with you, I just think it's a weird place to end up legally.
- dekhn 6y ago
  The way I think about it is: it's generally accepted that news reporters can go through the trash you throw in a garbage bin and leave on the street. If you want to protect your privacy, shred your trash or otherwise deny physical access to reporters. The burden is on the transmitter to protect their asset and if they don't, they're negligent.

mhh__ 6y ago

Anyone interested in how SDR works/is implemented: the book "Software defined radio for engineers" is the only book I've come across that combines DSP and SDR in the right ratios (Proakis's DSP book is bad if you want to build things straight away)

jcun4128 6y ago

Man that's awesome... crazy how your brain is "zoomed in" to your daily life/forget zoom out on this rock in nothingness like a film of bacteria.

dghughes 6y ago

As a young teen in the early 80s I read about a project that used an FM radio, a printer, and a bit of code to detect meteoroids. When the meteoroid became a meteor it gave off a frequency in the FM range. I liked programming but wasn't good at it and didn't understand what I needed. I wasn't sure if my Atari 600XL was suitable for the project but I do believe the code was BASIC which the 600XL could run. And I didn't have a printer which at the time was like owning a unicorn.

aasasd 6y ago

So, if people say here that plenty of folks receive satellite imagery, are there projects to assemble a complete map of the planet and have it continually updated? As in, you know, a satellite view for OSM.

aasasd 6y ago
Though, if this imagery is the same as what's on https://rammb-slider.cira.colostate.edu https://rammb-slider.cira.colostate.edu — then its resolution is apparently on the level of ‘I can see mountains’.

enginoor 6y ago

I feel that GOES satellite imagery is a hidden gem, I'm surprised more people aren't working with it. The imagery is available at https://www.star.nesdis.noaa.gov/GOES/ https://www.star.nesdis.noaa.gov/GOES/ but is better explored at https://rammb-slider.cira.colostate.edu/ https://rammb-slider.cira.colostate.edu/ I have personally built a Twitter bot to collect and animate imagery throughout the day. I have it running for two locations currently. Continental US: https://twitter.com/satellite_CONUS https://twitter.com/satellite_CONUS NorthEast US: https://twitter.com/satellite_NE https://twitter.com/satellite_NE It's amazing to see storm formation visually.

l00sed 6y ago
Very cool!
gavin_gee 6y ago
github link to source? would live to build one for PNW
Yhippa 6y ago
That is very cool, thank you. I just sat there and stared at it and had a Pale Blue Dot moment. This thing is so beautiful and here we are fighting about everything.

amelius 6y ago

Who do we have to thank for not encrypting this data? PS: Aren't these images available on the web anyway? Well, if not, perhaps this project could change that.

7kay 6y ago

The title first suggested that the article is about a security vulnerability of a satellite. The DoD actually held a CTF recently focused on the security of space systems. Information is on https://www.hackasat.com/ https://www.hackasat.com/ I'm looking forward to the public release of the exercises from the qualifying round which will be on June 19.