Multi-protocol L-band satellite communications decoder for Windows (and Linux if you compile it).
Decodes Inmarsat Aero (Classic Aero, Aero-H/H+) and Inmarsat-C/EGC signals in real time using RTL-SDR, HackRF, Airspy, Pluto+/AD936x, RTL-TCP, SDRplay, or SDR++ server sources. Voice call recording, aircraft tracking, and message output in one application.
This fork's testing builds: GitHub Releases.
Windows builds can be found on official project page: https://sarahsforge.dev/products/inmarscope
- Copyable tables — Copy button, right-click, or Ctrl+C copies decoded text from any pane
- Reset pane layout — visible button, View menu, or Ctrl+Shift+R restores default docking without changing radio settings
- Regional band plans — 27 bundled plans with 1,771 validated entries, searchable country/region names and independent A/B selection. Inmarsat plans cover I4A, 4F2, 3F5, 4F3 and 6F1, plus historical 4F1. Selecting a satellite plan tunes to channel groups that fit the receiver bandwidth; individual frequencies are selectable. See the catalogue for coverage and dated survey limitations; this is not every country worldwide.
- Pop-out panes — drag a tab out of the dock to float it anywhere on the desktop
- PPM adjustment — crystal offset control for RTL-SDR, RTL-TCP, dual RTL, HackRF, and Airspy
- Inmarsat Aero — 600/1200/8400 bps OQPSK signal decoding, voice AMBE decoding, ACARS/ADS-C/CPDLC message parsing
- Inmarsat-C / EGC — 1200 bps BPSK decoding with EGC SafetyNet/FleetNet message output
- SDRplay — model-discovered antenna selection, sample rates, bandwidth, gains, AGC, PPM, DC/IQ correction and driver-exposed settings (bias tee, notch filters, external reference and HDR where supported). Requires SoapySDRPlay3 and the SDRplay API service; see SDRPLAY.md.
- Dual-SDR voice follow — use two RTL-SDRs, two SDRplay devices, or the two RSPduo tuners for separate spectra and voice following
- Voice call recording — WAV and OGG Vorbis output, tagged with aircraft ICAO. Record voice calls is at the top of both Decoders and Voice Calls; format and folder settings are in Decoders.
- Live spectrum & waterfall — real-time FFT with drag-to-place decoder placement
- Embedded flight map (Windows) — only aircraft detected by receivers A/B can appear. Decoded ADS-C coordinates take priority; optional ADSB.lol lookups provide positions for received identities without coordinates. Blue markers are decoded, orange markers are online positions. Lookup sends only received ICAO IDs, never message contents. OpenStreetMap provides background tiles; incoming aircraft never change your pan/zoom.
- SBS/BaseStation output — TCP server on port 30003 for virtual radar clients
- JAERO-compatible output — JSON dump, text log, and UDP forwarding
- Country blacklist — mute and skip recording for selected countries using ICAO address lookup
InmarScope supports building for Windows (MSYS2 MINGW64) and Linux (Debian/Ubuntu, Arch, Fedora).
View build instructions at COMPILE.md.
This fork's GitHub Actions builds Windows, Linux and macOS release assets. See CI setup and release guide and hardware testing.
This software is licensed under the GNU General Public License v3.0, available to view at LICENSE.