GNU Radio flowgraphs run in-browser via WebAssembly without local install

The project ports GNU Radio’s DSP stack and Qt GUI sinks to WebAssembly, allowing flowgraphs to execute in a browser tab. This removes the need for a local Python environment or GNU Radio installation, which typically requires system-level dependencies and build steps. Engineers can now open a browser, load a .grc file, and run the flowgraph immediately, making it easier to share and test designs without environment setup overhead.

Hardware integration is handled through WebUSB, enabling the browser to communicate directly with RTL-SDR, PlutoSDR, and HackRF devices. This approach avoids native driver installation but depends on browser support for WebUSB and the user granting device access. Performance may vary compared to native builds, particularly for high-sample-rate applications or complex flowgraphs, due to WebAssembly’s overhead and browser resource limits.

The editor maintains compatibility with native GNU Radio by reading and writing the same .grc file format. This allows engineers to prototype in the browser and later move the flowgraph to a native environment for deployment or performance tuning. The project also includes example flowgraphs and IQ recordings, which can be used for testing or educational purposes without requiring physical hardware.

While the browser-based runtime simplifies access, it introduces constraints not present in native GNU Radio. WebAssembly’s memory model and browser sandboxing may limit the size of buffers or the complexity of flowgraphs. Additionally, not all GNU Radio blocks or hardware interfaces may be available, and real-time performance could be impacted by browser garbage collection or other tab activity.