Why SDR-SLC exists
Systems, radio & architecture: exploring engineering through software-defined radio, embedded systems and communication systems.
My name is Ivo van Ling (PA2IX). I have spent more than 30 years designing communication systems, telecom platforms and critical infrastructure. Amateur radio has been my playground for almost as long. This project brings those two worlds together.
Over the past few years I have been designing an open Software Defined Radio ecosystem. It includes RF hardware, embedded firmware, desktop software and, perhaps most importantly, the communication protocols that allow those building blocks to work together.
The hardware is only one part of the system. Long before designing PCBs, I spent a considerable amount of time thinking about the interfaces between those components. If those interfaces are designed well, the hardware, firmware and software can evolve independently without breaking the overall architecture.
That philosophy runs throughout the project. Rather than inventing proprietary solutions, the SDR ecosystem builds on established technologies wherever possible. I/Q samples are transported using the VITA-49 standard. Radio discovery uses mDNS. Control and status information are exchanged using simple JSON messages over TCP/IP. The goal is not to create yet another SDR protocol, but to define a system that is easy to understand, extend and integrate.
Open systems begin with open interfaces.
The complete protocol specifications, hardware designs, firmware and software are published openly. They are not included merely as documentation of this project, they are intended to be used. Whether you want to build compatible hardware, experiment with your own DSP software or simply understand how the system fits together, everything starts with clearly defined interfaces.
The articles that follow tell the story behind those design decisions. They are not build logs. They explain why the architecture looks the way it does, why certain responsibilities ended up where they did and, just as importantly, why others didn’t.
If you’re interested in the engineering decisions that shaped the architecture, start with The First Design Decision Had Nothing to Do with Radio.