One desktop app for VHF airband monitoring and 1090 MHz ADS-B. It runs three receivers at once, each filled by whichever SDR you plug in:

Any role can use an RTL-SDR, Airspy, SDRplay (RSP1A/RSP2/RSPduo/ RSPdx), or a WAV file. Roles you don't need (2 and 3) can be set to Disabled.

Official Windows builds are published at sarahsforge.dev/products/airscope — that is the only place to get them.

Built in C++17 with Dear ImGui / ImPlot and OpenGL. AirScope started life as InmarScope (an Inmarsat decoder); the satellite path has been removed and the code retargeted to the airband and ADS-B.

• ACARS decoding with application layer output (CPDLC / ADS-C / MIAM) via libacars
• VDL2 — ACARS over VHF Data Link Mode 2 on the ACARS/VDL2 receiver, decoded with a vendored dumpvdl2 core. Tune near 136.975 MHz (primary) or the other VDL2 channels (136.875 / 136.725 / 136.775 / 136.925 ...); the channels that fall inside the receiver's bandwidth are scanned automatically
• AM voice with squelch, live listening and WAV/OGG recording
• Voice scanner — watches the spectrum and automatically opens a decoder on each new voice call, following the active one and closing it when it ends
• ADS-B — Mode-S demodulation, 1/2-bit CRC repair, DF17/18 decoding and CPR position tracking
• Aircraft table and live map, merged from ACARS and ADS-B positions
• Beast and SBS/BaseStation output for virtual-radar clients
• Persistent archive (SQLite) and a built-in web dashboard

Needs CMake, Ninja and a C++17 compiler; see COMPILE.md for the per-platform dependencies (librtlsdr, libacars, and optionally libairspy / sdrplay).

cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release
ninja -C build
./build/AirScope

1. Pick a source for each receiver (or set 2/3 to Disabled).
2. Press Start.
3. On the Voice receiver, Ctrl+click the spectrum to add a channel, or turn on the Voice Scanner to find calls automatically.

Settings (tuning, gain, squelch, scanner, output, layout…) are saved to airscope.ini and restored on restart.

AirScope is GPLv3 — see LICENSE. The ADS-B decoder is ported from goadsb (MIT, itself derived from dump1090) and the ACARS decoder from acarsdec; both are GPL-compatible.