This transcript summarizes the Open Research Institute (ORI) FPGA projects meetup on May 13, 2025. Key discussions included updates on the Earth-Venus-Earth (EVE) link analysis and upcoming collaboration with the Deep Space Exploration Society (DSES) for EVE2026. Aaron reported progress on DVB-S2 decoding and planned encoder implementations for the PlutoSDR and OpenCPI. Pete introduced a novel energy transmission efficiency metric for multipath channels, particularly relevant for deep space communications, and outlined a potential series of articles on waveform design and channel prediction in the delay Doppler domain. St. Paul provided updates on Remote Labs West system configurations and performance testing. A significant portion of the meeting, involving Matthew and Michelle, focused on refining the hardware-software partitioning strategy for the Opulent Voice protocol, exploring the feasibility of software-based Opus encoding on the Zynq platform versus hardware-implemented priority queues, framing, preemption handling, and ensuring portability across diverse hardware architectures.
ORI Projects Meetup: Updates on EVE, Opulent Voice, Remote Labs, and Communications Research
0:00 Meeting Introduction: The meetup serves as a forum to discuss progress, future plans, roadblocks, and resource needs for ORI's FPGA projects.
0:32 Thomas's Absence and Workshop: Thomas is attending the Beyond Earth workshop on lunar and space radio missions (May 12-15) and will report back on lessons learned and work presented from groups like Dwingeloo, Stockart, and DSES.
1:31 Earth-Venus-Earth (EVE) Link Analysis: A major update to the analysis document was published, with ongoing work needed, specifically refining the system temperature section of the link budget.
2:09 DSES Meeting for EVE2026: A meeting is scheduled to discuss EVE 2026 plans with DSES principals, covering link budgets and potentially large dish measurement techniques.
2:41 Non-Profit Tax Filing: ORI's annual 990 tax form is prepared for review and submission by the May 15th deadline.
3:40 QEX Magazine Articles: All four articles submitted from ORI/ARRL have been accepted for publication over the next year in QEX magazine.
4:03 IEEE P1954 Meeting: The meeting for the drone radio protocol standards group, relevant to the Neptune OFDM project, has been postponed to June.
4:48 Pete's Delay Doppler Article: Pete's article on delay Doppler channel communications is progressing well.
5:02 Amateur LTE Legality Article: A recently published article proposing a regulatory framework for amateur LTE communications has been picked up and linked by other outlets.
5:27 Opulent Voice State Machine Planning: Significant planning is underway for the Opulent Voice protocol's state machine, which will manage different data types (chat, file, voice, authentication), though no lab progress is reported yet.
6:07 Defcon Board Meeting: A proposal is being discussed to hold an ORI board meeting at Omega Mart in Las Vegas during Defcon weekend.
6:38 Ribbit Project UI Update: A user interface update for the Ribbit project was announced but is not yet visible in the web app, requiring further investigation.
8:41 Energy Efficiency Metric: Pete presented a metric to evaluate energy transmission efficiency in multipath channels, defined as the ratio (in dB) of energy received to energy transmitted per symbol.
11:06 Waveform Design Justification: While single-path efficiency is independent of waveform shape, multipath efficiency is dependent on the waveform (X(t)), justifying efforts in designing specific waveforms for such channels (like EVE).
12:21 Proposed Article Series: Pete is considering a series of short articles covering the new metric, applying it to delay Doppler waveform design, and channel prediction in the delay Doppler domain, aiming for clearer educational material on topics like OTFS.
15:41 Application to EM/EVE: The research is particularly relevant for Earth-Moon-Earth (EME) and Earth-Venus-Earth (EVE) communication, where channels like the Moon's rigid surface may allow better prediction.
19:17 System Management: Two copies of the remote lab computer system (live and test) are maintained for development and deployment.
19:38 Unraid Version Updates: The systems are running slightly older versions (7.0.1 live, 7.1.0 test); updates to the latest 7.1.0.001 are planned for the test system, followed by the live system.
20:11 Performance Testing: Preliminary tests to improve performance using SSDs are ongoing.
21:28 MSK Modem Refinement: Matthew is cleaning up the MSK modem code, debugging the demodulator via simulation, and refining the differential encoder implementation, focusing on pipeline data alignment for robustness.
23:48 Opulent Voice Partitioning: Matthew and Michelle had an in-depth discussion on splitting Opulent Voice tasks between hardware and software.
24:12 Hardware Framing/Queuing: Matthew argued for hardware handling a simple framing structure and priority queues (potentially 3 levels) to manage different data types and send dummy frames (like PRBS) to maintain receiver lock, especially for portability.
25:17 Software Opus Encoding: Michelle noted the lack of open-source hardware Opus encoders and explored the feasibility of running Opus encoding software on the Zynq 7010's ARM processor, which initial findings suggest might be possible at voice rates.
33:22 Preemption Challenge: A key detail is how to handle preemption β switching to a higher priority data stream (like live voice) if it becomes active while a lower priority stream is currently transmitting within a frame.
36:43 Portability Considerations: A major factor driving the hardware/software split is ensuring the protocol can be easily ported to platforms beyond integrated Zynq systems, such as a combination of a Raspberry Pi and a separate FPGA, where the interface becomes a bottleneck.
34:36 Collaborative Design: The team agreed on the value of a collaborative design process with detailed proposals and critiques to reach an optimal solution for the Opulent Voice architecture.