go2signals go2DECODE Features


Manual and Automatic Signal Monitoring

go2DECODE can be used to monitor a single frequency.

The Automatic Production Channel (APC) buffers the incoming signal, allowing lossless detection and decoding without losing the first bit of an emission.

When a signal is detected, the APC searches the modem list for known modem types. Signal parameters such as center frequency and baud rate are determined and displayed. Decoded text is displayed as plain text or as a formatted XML stream. Digital audio can be played back. All the output can be saved to disk.

Manual Analysis of Unknown Signals

Unknown signals can be recorded (automatically or manually). Later these recordings are used for signals analysis, measuring modulation and coding parameters. A wide set of integrated analysis tools supports the analyst. This information and recordings can be later used to modify existing or implement new decoders.

Creation of New Decoders

In contrast to other products, the end customer has the possibility to create his own or to modify existing decoders.

The operator is able to set up a demodulator and parameterize the demodulator for a signal.

With the Python Decoder Description Language (pyDDL) new decoders ca be created. Existing decoders can be modified because the pyDDL source code of many decoders is part of the package. A debugger (Spyder) is also part of the go2DECODE Professional version.

The decoders implemented in go2DECODE can be exported to go2MONITOR by simple drag and drop.


Recognition & Decoding

go2DECODE’s signal detection and production is a multi-level process. go2DECODE buffers the incoming signal continuously. Buffering allows loss-less demodulation in time respect. go2DECODE checks the signal for the predefined modem types in the steps:

  • Detection
  • Recognition
  • Demodulation and decoding.

Signal characteristics (e. g. center frequency and symbol rate) are determined and displayed. Decoded text will be displayed as plain text or as a formatted XML-stream.
Because of this multi-level process a modulation classification, a modem recognition and a complete production can be realized with go2DECODE. Thus even incomplete processing steps lead to partial results. Quality criterion's of all results are calculated and displayed.
For best results, code aided and soft-decision decoders are implemented in some decoders.

Processing of Voice Signals

A powerful voice detection module is integrated. The voice processing algorithms of go2DECODE are insensitive to interference's like wideband interference caused by a thunderstorm.
The sensitivity level itself can be parameterized. In addition to the decision “voice yes or no” the module determines the values for nominal frequency, voice pitch and modulation type.
The voice transmission can be demodulated and stored in audio files for listening and further processing. All this is done in real-time and tailored to the typical COMINT signal scenario.


Besides demodulation and decoding of radio signals, signal recording is an important application in daily use. The signal recording not only provides the material for the manual technical analysis of unknown signals, but also for archiving the signals of interest. go2DECODE allows recording of both IF and AF during demodulation.
The recordings are started and stopped either via automatic triggers or manually by the operator. The triggers supported by go2DECODE are;

  • Configurable squelch
  • Signal detection
  • Modem recognition
  • Voice detection

go2DECODE can record the demodulated bit stream into a txt file or into a special go2DECODE file format that contains additional metadata such as the quality of each bit.

Signal Analysis

Precise measurements can be obtained with the displays provided by go2DECODE. All the important tools needed to determine the signal characteristics are available:

  • Spectrum display
  • Spectrum/Spectrogram display
  • Auto correlation display
  • Constellation display
  • Time display
  • Analysis display (for the simultaneous interpretation of magnitude, frequency and phase of a signal to get a first impression of the used modulation)
  • Hell display
  • Bit display

Hell and bit display show information about the used coding. In each display cross-hair or harmonic cursors are offered.
This powerful tool kit can be used to get the required parameters to setup new demodulators for decoders(modems).

DANA (Digital analogue audio interface)

Two signal sources are available:

  • Analogue signals from the sound card, mixing console or virtual audio cables
  • File, wav (IQ, real) .

Single files or a play list can be played back.

Various settings are available for:

  • Sampling rate conversion
  • Filtering
  • DC removal
  • Mirroring
  • Time source (realtime/file time)
  • Center frequency tuning
  • Sound card configuration
  • Automatic buffer flushing at the end of the file
  • Loop mode
  • FM demodulation.


The PMO tool can be used to manage the output of the decoder. AF recordings, IF recordings, Binary results and production results are displayed in a structured list and lets the user select the specific data in a comfortable way. You can define which tools will be pop up if you call the context menu (right mouse click).

You can specify which external applications are used for  display or processing

  • Play audio recording
  • Display decoder output
  • Play IF-recordings (maybe with DANA)
  • Display binary data with a hex viewer