Tagged: satellite

Saveitforparts Checks out the Discovery Dish

Over on his YouTube channel 'saveitforparts,' Gabe has uploaded a video checking out and reviewing our Discovery Dish product that we successfully crowd-funded on CrowdSupply back in December 2023.

Discovery Dish is designed as a low-cost way to dive straight into backyard satellite experiments, including receiving L-band and S-Band weather satellites as well as Inmarsat satellites. It also offers an easy entry into making galactic Hydrogen line observations.

The dish is a 70cm prime focus dish, that can easily be broken down into three parts for easy storage and transport. The feeds are fully integrated, meaning that the feed antenna, LNA, and filtering are all in one unit and built into a waterproof enclosure. This means there is no need to purchase individual components and figure out waterproofing.

In his video, Gabe unboxes the Discovery Dish, builds it, and uses the L-band feed to receive a few images from GOES 16, Meteor M3, Meteor M4, and METOP weather satellites. He goes on to successfully test reception with the S-band feeds on NOAA weather satellites, before testing out the Inmarsat feed and successfully receiving signals. Finally, Gave notes that he hopes to test out the Hydrogen Line feed in a future video.

Checking Out The Discovery Dish - A Simple & Easy-To-Use Satellite Antenna For Everyone!

CCC Conference Talk: Investigating the Iridium Satellite Network

Over the years, we've posted numerous times about the work of “Sec” and “Schneider,” two information security researchers who have been investigating the Iridium satellite phone network using SDRs. Iridium is a constellation of 66 satellites in low Earth orbit that supports global voice, data, and messaging services.

In a talk at the Chaos Computer Club (CCC) 2024 conference, they provided updates on their work. The recorded video of their talk has recently been uploaded to YouTube.

The Iridium satellite (phone) network is evolving and so is our understanding of it. Hardware and software tools have improved massively since our last update at 32C3. New services have been discovered and analyzed. Let's dive into the technical details of having a lot of fun with listening to satellites.

We'll cover a whole range of topics related to listening to Iridium satellites and making sense of the (meta) data that can be collected that way:

  • Overview of new antenna options for reception. From commercial offerings (thanks to Iridium Time and Location) to home grown active antennas.
  • How we made it possible to run the data extraction from an SDR on just a Raspberry Pi.
  • Running experiments on the Allen Telescope Array.
  • Analyzing the beam patterns of Iridium satellites.
  • Lessons learned in trying to accurately timestamp Iridium transmissions for future TDOA analysis.
  • What ACARS and Iridium have in common and how a community made use of this.
  • Experiments in using Iridium as a GPS alternative.
  • Discoveries in how the network handles handset location updates and the consequences for privacy.
  • Frame format and demodulation of the Iridium Time and Location service.
38C3 - Investigating the Iridium Satellite Network

Saveitforparts: Hacking an Motorized RV Satellite Dish for Tracking LEO Satellites

Over on the saveitforparts YouTube channel, Gabe has uploaded a new video showing how he's hacking an old motorized Wineguard RV satellite dish for tracking low earth orbit satellites, such as the NOAA and Meteor weather satellites as well as the US Military's DMSP system.

The motorized RV satellite dish was originally intended for tracking TV satellites, but by connecting to the serial port on the control unit, Gabe is able to control the satellite dish through his own code.

In this video I'm creating a motorized satellite tracker for S-Band signals. S-Band includes NOAA weather satellites and the US Military's DMSP system (it's also the radio band for WiFi, which I might look at later).

I'm using a Winegard brand "Trav'ler" antenna designed for use on campers and recreational vehicles. It has a built-in three-axis motor system for pointing at TV satellites, but I wanted to use it for tracking satellites closer to earth. Since a low-orbit satellite like NOAA 18 or DMSP passes overhead in about 10 minutes, I need to move the dish faster and more precisely then it was intended for.

This project is still ongoing, and I don't yet have the code up on Github. When I do, it will be available at https://github.com/saveitforparts/ alongside the code for some similar antennas I've hacked in the past.

The serial cable I'm using is described here: https://saveitforparts.wordpress.com/2023/12/29/another-portable-radio-telescope/

Modifying RV Satellite Dish To Track Low-Earth-Orbit Satellites

Saveitforparts: Testing a 3D Printable Satellite Antenna for NOAA, Meteor and other Polar Orbiting L-Band Satellites

Over on the saveitforparts channel, Gabe has uploaded a video showing a 3D-printable helicone antenna for receiving weather images from polar-orbiting L-band satellites like NOAA and Meteor. This antenna has become popular in the community as it is relatively easy to build, lightweight, and small enough to be handheld. The 3D model files are available on Thingiverse.

In the video, Gabe shows that initially, he had multiple failed print attempts on the helical scaffold due to the legs warping. He was able to solve this and get a working print by slightly modifying the 3D model to have additional center supports. He then goes on to show the rest of the build, which involves coiling the helix antenna, cutting the reflector out of sheet metal, screwing together the reflector supports, and mounting the reflector mesh.

Finally, he shows that he was able to get successful image reception from NOAA HRPT satellites using hand tracking, with a phone running an RTL-SDR and SatDump for tracking and decoding.

This 3D-Printed Satellite Antenna Is Fantastic!

Saveitforparts: Receiving the Bitcoin Blockchain from the Blockstream Satellite Network

Over on his YouTube channel 'saveitforparts' has uploaded a new video showing how he was able to download the Bitcoin blockchain via the Blockstream Satellite network. The Blockstream satellite network allows people in remote communities without an internet connection to receive the entire Bitcoin blockchain via satellite. With the blockchain Bitcoin users can confirm if a payment to them has been made.

After several failed attempts, he was finally able to receive and decode the signal using a fold-out satellite dish with an LNB and an RTL-SDR Blog V4. He also attempts to use the encrypted messaging feature on the blockstream satellites. However, while the message appears to have been received, he was unable to actually view the message due to an error. He writes:

A while back I heard about the Blockstream Satellite network, which claims to offer real-time streaming of the Bitcoin blockchain to anyone with a satellite dish. While I still don't understand cryptocurrency, I thought the satellite part of this sounded interesting!

It took a while to locate the correct satellite (Galaxy 18 in North America), and to get the software working, but eventually I was able to start downloading the blockchain file. What to do with it next, I have no idea!

I also tried sending messages through the satellite, but unfortunately I wasn't able to decode them on the receiving end. I gave up on this since I didn't want to spam everyone on the global network!

You can find out more about the Blockstream Satellite system on their website: https://blockstream.com/satellite/

And you can find instructions on using the system here:https://blockstream.github.io/satellite/doc/sdr.html

I used https://www.dishpointer.com/ to help align my antenna.

I also used https://www.lyngsat.com/ and https://www.satbeams.com/ to identify which satellites I was detecting.

I Found Bitcoin On A Satellite In Space

Investigating the Transit 5B-5/E-5 Satellite: The oldest satellite still transmitting

Transit 5B-5 is a US Navy navigation satellite that was an early version of the GPS/GNSS system we enjoy today. It was launched in 1964 and has been transmitting continuously for roughly 60 years. Unlike many dead satellites that only emit a carrier tone, this one still broadcasts modulated telemetry on about 136.65 MHz, making it a fascinating target for amateur radio and SDR hobbyists.

Over on YouTube dereksgc has uploaded a video that is a deep dive into the Transit satellites, and tries to unravel the convoluted naming scheme. In the video, dereksgc digs into historical documents and compares orbital decay rates, modulation schemes, and expected signal formats.  The results strongly suggest that this “Transit 5B-5” signal may actually be coming from a different spacecraft altogether, likely “Transit 5E-5.” 

Detailed SDR recordings and analysis of its subcarriers and data rates reveal that the format, frequency, and stability align better with the Transit 5E series rather than the navigation-oriented Transit Oscar series as previously believed.

If you are interested in receiving Transit 5B-5/5E-5, you can do so with a simple RTL-SDR and 137 MHz antenna, which is commonly used for NOAA and Meteor weather satellite reception. We have posted about receiving Transit 5B-5/5E-5 before on this previous post too.

The oldest satellite still transmitting (and its complicated identity)

Receiving Starlink Signals with an RTL-SDR and Ku-Band LNB

Over on YouTube, dereksgc has uploaded a new video showing how to receive signals from Starlink satellites using an RTL-SDR and a standard Ku band LNB. Note that this setup simply receives the raw signals, and it does not allow you to connect to the Starlink service.  

In the video, dereksgc first introduces Starlink satellites and explains what signals they transmit, referencing a paper on the structure of the Starlink Ku-band downlink by researchers at the University of Texas. He notes that the signals are strong enough that a single LNB without a dish is sufficient for receiving them. An LNB is a feedhorn antenna, low-noise amplifier, and downconverter all-in-one. It converts the ~10.950 GHz Ku band signal of the Starlink satellites down to a frequency that the RTL-SDR can receive.

In the rest of the video, he shows a timelapse of signals being received. The signal's doppler shift can be seen and heard as the satellite passes over.

Receiving Starlink signals with RTL-SDR

SatDump 1.2.1 Released

SatDump is a popular program used to receive and decode images and other data from various weather satellites. SatDump works great RTL-SDR Blog dongles and with our Discovery Dish, an easy-to-use dish and feed for receiving L-band and other weather satellites. Recently SatDump version 1.2.1 was released, which brings several new features including:

  • Meteor-M Calibration - Temperatures and radiances are now available from the Meteor-M infrared channels, including enhancements like Cloud Top IR.
  • Archive Loader & EUMETSAT Archives (and EUMETCAST) Support: Metop, Meteosat, Sentinel-3 and more! - Users can now open data from the EUMETSAT archives in SatDump.
  • Windows ARM64 Support - One of the few SDR programs that has Windows ARM64 support.
  • JUICE Support - JUICE (JUpiter ICy moons Explorer) is an ESA probe tasked to study three of the Galilean moons of Jupiter, namely Ganymede, Callisto and Europa. During a recent Earth slingshot it was possible to receive.
  • AIRS and CERES Support - Hyperspectral sounder and radiation budget instruments on the Aqua satellite
  • Arctic Weather Satellite Support - AWS is a weather satellite recently launched in July 2024 with 1707 MHz downlink and similar parameters to METOP, so it should be accessible to many.
  • IASI (imaging channel) Calibration - Calibration for the hyperspectral sounder onboard METOP satellites.
  • GOES-R L2 Product Support - Pre-processed models from NOAA that include Rain Rate per Quarter Hour, Land Surface Temperature, Sea Surface Temperature, and more.
  • GOME Fixes - True Color for METOP satellites.
  • Miscellaneous AVHRR and MHS Fixes - Calibration stripes and other strangeness is less likely to occur even with a bad signal.
  • Miscellaneous Composites - Many new composites are available.
  • Automatic Filename Templating - Customizable filename templates
  • More Quality-of-Life Features - Various tools and warnings added
  • RFNM Support - Support for the new RFNM SDR
  • Library Directory Fixes on Linux - Fixes SatDump on Gentoo and OpenSUSE among others.
  • Advanced Mode - Lets you change all TLE settings, composite configs, default pipeline settings, and more
  • Themes - Various new themes added
  • More Satellites Support - Initial support for XMM-Newton, VERONIKA and ACE
  • Experimental Windows XP Support - A special version of SatDump now runs on Windows XP SP3.
  • Various Bug Fixes
SatDump Running on Windows XP
SatDump Running on Windows XP