go2DECODE Programming


Decoder Programming

An important feature of the go2MONITOR/go2DECODE software is the capability for the user to extend on its own the existing decoder library by using go2DECODE.
The user can develop or modify decoders and use them with the supplied set of universal demodulators.

Decoder Description Language (DDL, pyDDL)

Workflow

The user can define and create his own decoders, integrate existing ones or modify the integrated standard decoders. The evolutionary growing Decoder Description Language (DDL) is the most suitable toolbox for this task.

DDL offers many new features by using PYTHON language as base (pyDDL) for future development. Decoder development is done with the enormous set of commands and libraries provided by PYTHON and the additional dedicated set of more than 100 special commands e.g. for pre-processing, searching, reading, transformation and output formatting. The instruction set is designed not only for basic recognition and synchronization tasks, but also for complex channel decoding techniques.

All supplied decoders were built on this basis. Where available, users can use these decoders as models for their own solutions.
The starting point is a demodulated bit stream supplied by an appropriately parameterized demodulator. DDL allows the analysis and processing of bit streams to generate decoded message content. In this way, even modern channel decoding methods can be applied in just a few steps.

The decoders can be used in other go2SIGNALS installations (e. g. go2MONITOR) as well as in other wireless monitoring systems with the same technology (PLATH). The DDL ensures high decoding quality, i. e. fast synchronization, selectivity, correction capabilities, etc.

The powerful programming language (DDL) reduces the size of the decoder and thus the possible number of errors, which reduces the development time.
From the DDL it is also possible to call DLL's in C, C++ or other programming languages.

DDL Debugger (part of the professional version)

Decoders are preferably created and testedusing specialised tools. This way, decoder developers obtain the best possible insight into
the entire modem function flow. go2DECODE’s pyDDL-based decoder development tools consist of Spyder as integrated editor and
debugger.

Spyder is used to create and modify the pyDDL scripting source code. The editor offers automatic command completion and context sensitive help. Correct commands, functions and keywords are highlighted in color for visual checks. In the case of coding errors, the PYTHON scripting interpreter logs detailed error messages to help debugging code.

The debugger is used to verify the executable code. This application makes it possible to analyze the decoding process in detail. The large set of functionalities meet customers’ expectations on a modern development platform regarding:

  • Testing of isolated decoder sections
  • Verifying intermediate results
  • Stepping through the source code line by line
  • Monitoring variables and intermediated buffers with each step
  • Changing variable values at any step
  • Defining breakpoints within the program to stop continuous operation
  • Running decoders independent of real time baud rate (i.e. faster or slower)