Category: Applications

SDRAngel Features Overview: ADS-B, APT, DVB-S, DAB+, AIS, VOR, APRS, and many more built-in apps

SDRAngel is a general purpose software defined radio program that is compatible with most SDRs including the RTL-SDR. We've posted about it several times before on the blog, however we did not realize how much progress has occurred with developing various built in plugins and decoders for it.

Thanks to Jon for writing in and sharing with us a demonstration video that the SDRAngel team have released on their YouTube channel. From the video we can see that SDRAngel now comes stock with a whole host of built in decoders and apps for various radio applications making it close to an all-in-one SDR platform. The built in applications include:

  • ADS-B Decoder: Decodes aircraft ADS-B data and plots aircraft positions on a map
  • NOAA APT Decoder: Decodes NOAA weather satellite images (in black and white only)
  • DVB-S: Decodes and plays Digital TV DVB-S and DVB-S2 video
  • AIS: Decodes marine AIS data and plots vessel positions on a map
  • VOR: Decodes VOR aircraft navigational beacons, and plots bearing lines on a map, allowing you to determine your receivers position.
  • DAB+: Decodes and plays DAB digital audio signals
  • Radio Astronomy Hydrogen Line: With an appropriate radio telescope connected to the SDR, integrates and displays the Hydrogen Line FFT with various settings, and a map of the galaxy showing where your dish is pointing. Can also control a dish rotator.
  • Radio Astronomy Solar Observations: Similar to the Hydrogen line app, allows you to make solar measurements.
  • Broadcast FM: Decoding and playback. Includes RDS decoding.
  • Noise Figure Measurements: Together with a noise source you can measure the noise figure of a SDR.
  • Airband Voice: Receive multiple Airband channels simultaneously
  • Graves Radar Tracker: For Europeans, track a satellite and watch for reflections in the spectrum from the French Graves space radar. 
  • Radio Clocks: Receive and decode accurate time from radio clocks such as MSF, DCF77, TDF and WWVB.
  • APRS: Decode APRS data, and plot APRS locations and moving APRS enabled vehicles on a map with speed plot.
  • Pagers: Decode POCSAG pagers
  • APRS/AX.25 Satellite: Decode APRS messages from the ISS and NO-84 satellites, via the built in decoder and satellite tracker.
  • Channel Analyzer: Analyze signals in the frequency and time domains
  • QSO Digital and Analog Voice: Decode digital and analog voice. Digital voice handled by the built in DSD demodulator, and includes DMR, dPMR and D-Star.
  • Beacons: Monitor propagation via amateur radio beacons, and plot them on a map.

We note that the video doesn't show the following additional features such as an analog TV decoder, the SDRAngel "ChirpChat" text mode, a FreeDV decoder and several other features.

SDRangel

Multichannel ALE and GMDSS Decoding with Black Cat Systems Software

Black Cat Systems have recently released two new programs that may be of interest to HF monitoring enthusiasts. The first is a multichannel capable ALE decoder and the second is a multichannel GMDSS-DSC decoder. Both programs are not free, with an (introductory) price tag of $29.99 each for three parallel input channels, and $99 for up to 24 parallel input channels.

With an appropriate HF capable SDR, like a SDRplay, Airspy HF+ Discovery, or even an RTL-SDR V3 in direct sampling mode, these programs allow you to set up a home monitoring station. 

ALE or Automatic Link Establishment is a digital RF protocol that enables users to initiate a reliable call over HF frequencies, by automatically choosing the best frequency based on propagation conditions, allowing for telephone like calling operation, and enabling short text messages.

GMDSS or Global Maritime Distress and Safety System is a set of radio protocols that enables digital text communications between ship to ship and the shore, as well as weather broadcasts, and distress beacons. 

Over on his blog Nils Schiffhauer (DK8OK) has been testing these two programs out. In his first post about the ALE decoder, Nils explains ALE in more depth, and demonstrates how he uses the multi-channel capable SDR-Console with Virtual Audio Cable to feed 16 ALE channels into the decoder. He goes on to show how to filter by callsign and provides some tips for best reception. He notes that with ALE you might receive messages from:

... forces, diplomatic services, emergency agencies, police, militia, UN missions, drug enforcement, border control and even amateur radio. It is used from aircraft like AWACS, as from aircraft carriers, from mobile units to fixed stations. 

In his second post Nils tests out the GMDSS decoder noting that it is an "extraordinary sensitive decoder" and "it also includes smart processing of the data – from looking up vessel’s complete data from ITU’s Ship Station List (internet connection needed) to saving all data to a fully-fledged database". His post goes on to explain the GMDSS format in more detail and demonstrate multichannel decoding.

Black Cat Systems ALE and GMDSS Decoders demonstrated by Nils Schiffhauer (DK8OK)

SignalsEverywhere: Spectrum Analyzer and Tracking Generator with Pluto SDR

In the latest video on the Signals Everywhere YouTube channel, Sarah investigates how a PlutoSDR can be used as a Spectrum Analyzer with the SATSAGEN software. The SATSAGEN software is able to work as a spectrum analyzer by rapidly sweeping over multiple frequencies and stitching the spectrum slices together. It support SDRs like the HackRF, PlutoSDR and RTL-SDR (in receive mode only). The PlutoSDR can transmit, so it is able to work as a full spectrum analyzer with tracking generator, allowing users to measure RF devices such as filters, tune antennas, and work as a frequency generator.

In the video Sarah demonstrates how to use the PlutoSDR and SATSAGEN to measure our RTL-SDR Blog Broadcast FM filter, and to tune our multipurpose dipole antenna.

Spectrum Analyzer and Tracking Generator with Pluto SDR

LeanHRPT – A set of tools for the manipulation of HRPT data

Over on Reddit u/Xerbot has posted about the release of his new software called "LeanHRPT". When combined with a software defined radio, this software can be used to decode and view HRPT weather satellite images received from satellites such as NOAA, Meteor, MetOp and FengYun. We note that unlike APT and LRPT weather satellite signals which transmit in the VHF bands, HRPT signals are generally at ~1.70 GHz and require a motorized or hand tracked satellite dish to receive. u/Xerbot writes:

LeanHRPT is a flexible, easy to use and powerful set of tools for the manipulation of HRPT data (maybe I could be convinced to add LRPT support).

When used properly LeanHRPT Decode can generate (almost) L1B data usable in actual land/weather observation, or just pretty images :)

You can get it here: https://github.com/Xerbo/LeanHRPT-Decode

The LeanHRPT project also contains LeanHRPT Demod, as you probably guessed, a HRPT demodulator. It features an incredibly high sensitivity as well as being able to do both realtime (through SoapySDR) and offline demodulation (baseband).

You can get it here: https://github.com/Xerbo/LeanHRPT-Demod

LeanHRPT Applying a map overlay on FengYun

GNU Radio Conference 2021 Talks Now Available on YouTube

The GNU Radio YouTube channel has recently finished uploading the talks from GRCon21, this years annual GNU Radio Conference. GNU Radio is an open source development toolkit for signals processing and is commonly used to build software demodulators and decoders for Software Defined Radios.

The GNU Radio conference talks are generally about cutting edge SDR research topics and the YouTube playlist contains 67 videos covering a gambit between what changes have been made in new releases of GNU Radio to presentations and demonstrations focusing on topics such as reverse engineering smart power meters and 5G cell detection among many others.

Some of the talks from this years conference that we found most interesting include:

GRCon21 - Keynote: Joe Gibbs Racing Team

Lightweight Windows Software uSDR Updated to Version 1.4.0

Back in July we posted about the release of Viol Tailor's "uSDR" software, which is a lightweight general purpose multimode program for Windows which supports the RTL-SDR, Airspy, BladeRF, HackRF and LimeSDR radios. Recently Viol has updated the software to V1.4.0. The new release brings SDRplay support, and various performance and GUI improvements listed below.

The software can be downloaded from SourceForce.

  • customizable tool panel behavior (fixed, floating, undocked)
  • SDRPlay frontend support (API v.2.13)
  • RTL-TCP streaming interface support, presets quick switch (server, port, description)
  • high precision Wav IQ file play back
  • support RIFF 8, 16, 24 and 32 bits integer, 32 bits float, FR64 file formats for playback
  • recognize Wav IQ file central frequency for play back
  • frequency offset (shift) for x-verters
  • swap IQ (invert spectrum) option
  • improved FFT spectrum calculation and visualization
  • waterfall color map range may be changed manually on the spectrum window as well as on tool panel, also included the auto scale option
  • color map palette can be customized and fast switched, palette presets are included
  • FIFO buffer size (IQ history time) may be changed on the fly, all memory allocations are under hood, no losses of previously stored history 
  • pass band may be attachment to global frequency as well as to local baseband frequency or to screen position
  • squelched threshold control and level indicator for demodulation (in addition to adjustable spectrum threshold detector)
  • stereo FM demodulator
  • low latency audio
  • frequency manager, groups and interactive markers, visualize, edit, navigate, tune the pass band
  • spectrum and waterfall popup menus
  • improved GUI controls
  • "fine tune" option: set pass band to rounded frequency (spectrum right click)
  • statistics visualization window
uSDR aka microSDR. A lightweight SDR receiver program from Windows.

SignalsEverywhere: Setting up the Retrogram Terminal Spectrum Analyzer for the PlutoSDR

This week on the SignalsEverywhere YouTube channel Sarah shows how to install the "Retrogram" software. This is a command line 'retro' styled spectrum analyzer designed to be used with the PlutoSDR. The software makes use of ASCII art to display the spectrum, meaning that a spectrum can be viewed directly in an SSH terminal, without any GUI. 

In the video Sarah goes through the steps to install the software before demonstrating it in action.

Retrogram - A Command Line Spectrum Analyzer For The PlutoSDR

Tech Minds: Testing the Cloudmarkers SDRuno Community Plugin

This week on the Tech Minds YouTube channel Matthew introduces the "Cloudmarkers" plugin for SDRuno. SDRuno is the official software for the SDRplay RSP line of software defined radios, but the EXTio version also supports the RTL-SDR.

Cloudmarkers is a plugin that allows users to query the online Cloudmarkers database to determine what an unknown signal at the currently tuned frequency might be. The database is created by other Cloudmarkers users, so if you have your own information to add you can add information about particular frequencies to the database for others to query later.

In the video Matthew shows  the Cloudmarkers plugin in operation and notes that the plugin can work with both SDRplay SDRs and the RTL-SDR.

CLOUDMARKERS - Community Plugin For SDRuno