Software Defined Radio(SDR)/Digital Signal Processing(DSP)
Open Source Digital Voice for Space and Terrestrial Communications
<p>Abstract:
The Opulent Voice Protocol (OVP) is an open-source digital voice protocol designed for bandwidth-constrained radio communications, including satellite and terrestrial amateur radio links. Developed through the peer-reviewed research and development process at Open Research Institute, OVP addresses the critical need for high-quality voice communication protocols that are freely implementable without licensing restrictions.</p>
<p>Built around the 16 kbps Opus voice codec, OVP delivers superior voice quality that exceeds existing amateur digital voice modes while seamlessly integrating voice, keyboard chat, and data in a unified protocol. This eliminates the need for separate, clunky packet data modes. This talk will explore OVP's architecture, performance characteristics, and design trade-offs. The first implementation target for the modem is the PLUTO SDR and can be found here https://github.com/OpenResearchInstitute/pluto_msk</p>
<p>Key Technical Features in the Reference Implementation:
Minimum shift keying modulation has constant envelope and no phase discontinuities. Optimized for low SNR conditions, with forward error correction and flywheel synchronization. Efficient bandwidth utilization suitable for 70 cm and above amateur bands. Current hardware implementation on FPGA enables a future open source ASIC design. </p>
<p>We'll cover:
The architectural decisions behind OVP's design, showing how domain modeling of the radio channel shaped protocol choices. Audio quality comparisons between OVP and legacy digital voice modes. The integrated communication model, which allows voice, chat, and data to coexist in a single protocol. Performance analyses. Integration with existing SDR platforms and open-source radio stacks. Lessons learned from deploying OVP over the air. The peer-review process and how open collaboration improved the protocol. </p>
<p>Human-radio interface project is here: https://github.com/OpenResearchInstitute/interlocutor
Processor-side codebase (Xilinx/AMD 7010 Zynq) is here: https://github.com/OpenResearchInstitute/dialogus
Satellite simulator is here: https://github.com/OpenResearchInstitute/locus</p>
<p>This talk is relevant to anyone interested in software-defined radio, open hardware communications systems, space technology, or building robust protocols for constrained environments.</p>
Additional information
| Live Stream | https://live.fosdem.org/watch/k3601 |
|---|---|
| Type | devroom |
| Language | English |
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