Uploaded February 2025 | Updated September 2026, 13 hours ago
Quick Recap
The team discussed their ongoing projects, including the uplink protocol for their satellite project, the power detector, and a preamble/sync transmission feature. They also explored the challenges of fitting their design into the given Pluto platform and the potential of adding more features.
Next steps
• Matthew to continue optimizing the FPGA design to fit within the Pluto SDR's space constraints.
• Paul to provide more detailed analysis on oscillator drift and its potential impact on demodulation (report soon!)
• Abraxas3d to share documentation and readme files with Daniel about the Pluto_MSK project and its goals.
• Matthew to further explore using AI (Claude) for generating UVM test benches and share findings with the team.
• Rick to host a meeting to discuss recording noise data for the Earth-Venus-Earth experiment and share invitation details (12 February 2025)
• Rick to possibly investigate using SIGMF or VITA standards for storing signal data in the Earth-Venus-Earth experiment.
• Abraxas3d to create a separate video sharing insights from the ITA conference relevant to ORI projects.
Summary
In the meeting, Abraxas3d welcomed everyone and expressed gratitude for their attendance. She mentioned that there were some exciting developments in the past week, particularly regarding the uplink. Abraxas3d also shared that she had attended the Information Theory and Applications Conference in San Diego. Matthew was asked to share his work from the simulations he had been conducting, which he did. Aaron talked about his ZC706 and the 9371 work. Abraxas3d also encouraged everyone to visit opencpi.org for more information about the Open CPI project. Paul reported that there were no problems in the lab.
Signal Generator and Power Detector
Paul discussed his unsuccessful attempts to send an arbitrary waveform through the signal generator, which was a feature they had not tried before. Abraxas3d expressed hope to unlock this ability in the lab, anticipating the need to command different FPGA stations. Matthew then explained the power detector's function and how it could be used to compute a dBFS (full scale) value. He also mentioned the possibility of computing dBm from the signal chain if all gains and loading were known.
New Feature Improves Power Detection
Matthew presented a new feature in the repository, which includes the power detector and a sync transmission feature. The power detector was found to be more stable with a cascaded EMA filter, reducing variance in the power detection. The sync transmission feature transmits a 1 1 0 0 pattern, which can be configured to a longer or shorter number of bits. The feature was found to improve acquisition time. Abraxas3d discussed the potential benefits of the new features, particularly the use of a preamble to aid the receiver. She also mentioned ongoing issues with loop back testing over the air, which the new features aim to address.
Investigating Oscillator Drift and Error Rate
Matthew and Abraxas3d discussed the issue of a 0.4 bit error rate, which they suspected was related to oscillator drift. They noted that the frequency offset was a potential cause, but also considered the possibility of oscillator drift affecting the tracking loops. Paul mentioned that he had made some measurements on oscillator mismatch, but didn't know if it was significant enough to cause the error rate. They agreed to continue investigating the issue and improving their understanding of the loop gains.
Optimizing Design for Pluto Platform
Daniel and Abraxas3d discussed the challenges of fitting their design into the Pluto platform. Abraxas3d mentioned that they are confident they can make it work, but they can move to a larger FPGA. They also discussed the potential of adding more features to the design, which could push the boundaries of the current platform. Matthew added that they are starting to fill up the Pluto and there is an opportunity to prune out some of the original logic. He also mentioned the use of Claude AI to generate a UVM test bench, which was a productive tool but had some bugs. The team agreed to continue exploring options to optimize their design.
Optimizing Time and Pipeline Delay
Matthew discussed his progress on optimizing his time by focusing on features rather than writing test benches. He also mentioned a potential issue with the pipeline delay and his plan to ask Claude for help. Abraxas3d agreed with Matthew's approach and suggested it could be the subject of an article or presentation. Abraxas3d also mentioned some interesting findings from the ITA conference, but decided to wait for others to discuss their work before sharing these. Rick provided an update on his Deep Space Engineering Society (DSES) engineering meeting, mentioning the progress on the building and the upcoming Earth Venus Earth contact. He also discussed a potential issue with the link margin and suggested possible solutions.
Quick Recap
The team discussed their ongoing projects, including the uplink protocol for their satellite project, the power detector, and a preamble/sync transmission feature. They also explored the challenges of fitting their design into the given Pluto platform and the potential of adding more features.
Next steps
• Matthew to continue optimizing the FPGA design to fit within the Pluto SDR's space constraints.
• Paul to provide more detailed analysis on oscillator drift and its potential impact on demodulation (report soon!)
• Abraxas3d to share documentation and readme files with Daniel about the Pluto_MSK project and its goals.
• Matthew to further explore using AI (Claude) for generating UVM test benches and share findings with the team.
• Rick to host a meeting to discuss recording noise data for the Earth-Venus-Earth experiment and share invitation details (12 February 2025)
• Rick to possibly investigate using SIGMF or VITA standards for storing signal data in the Earth-Venus-Earth experiment.
• Abraxas3d to create a separate video sharing insights from the ITA conference relevant to ORI projects.
Summary
In the meeting, Abraxas3d welcomed everyone and expressed gratitude for their attendance. She mentioned that there were some exciting developments in the past week, particularly regarding the uplink. Abraxas3d also shared that she had attended the Information Theory and Applications Conference in San Diego. Matthew was asked to share his work from the simulations he had been conducting, which he did. Aaron talked about his ZC706 and the 9371 work. Abraxas3d also encouraged everyone to visit opencpi.org for more information about the Open CPI project. Paul reported that there were no problems in the lab.
Signal Generator and Power Detector
Paul discussed his unsuccessful attempts to send an arbitrary waveform through the signal generator, which was a feature they had not tried before. Abraxas3d expressed hope to unlock this ability in the lab, anticipating the need to command different FPGA stations. Matthew then explained the power detector's function and how it could be used to compute a dBFS (full scale) value. He also mentioned the possibility of computing dBm from the signal chain if all gains and loading were known.
New Feature Improves Power Detection
Matthew presented a new feature in the repository, which includes the power detector and a sync transmission feature. The power detector was found to be more stable with a cascaded EMA filter, reducing variance in the power detection. The sync transmission feature transmits a 1 1 0 0 pattern, which can be configured to a longer or shorter number of bits. The feature was found to improve acquisition time. Abraxas3d discussed the potential benefits of the new features, particularly the use of a preamble to aid the receiver. She also mentioned ongoing issues with loop back testing over the air, which the new features aim to address.
Investigating Oscillator Drift and Error Rate
Matthew and Abraxas3d discussed the issue of a 0.4 bit error rate, which they suspected was related to oscillator drift. They noted that the frequency offset was a potential cause, but also considered the possibility of oscillator drift affecting the tracking loops. Paul mentioned that he had made some measurements on oscillator mismatch, but didn't know if it was significant enough to cause the error rate. They agreed to continue investigating the issue and improving their understanding of the loop gains.
Optimizing Design for Pluto Platform
Daniel and Abraxas3d discussed the challenges of fitting their design into the Pluto platform. Abraxas3d mentioned that they are confident they can make it work, but they can move to a larger FPGA. They also discussed the potential of adding more features to the design, which could push the boundaries of the current platform. Matthew added that they are starting to fill up the Pluto and there is an opportunity to prune out some of the original logic. He also mentioned the use of Claude AI to generate a UVM test bench, which was a productive tool but had some bugs. The team agreed to continue exploring options to optimize their design.
Optimizing Time and Pipeline Delay
Matthew discussed his progress on optimizing his time by focusing on features rather than writing test benches. He also mentioned a potential issue with the pipeline delay and his plan to ask Claude for help. Abraxas3d agreed with Matthew's approach and suggested it could be the subject of an article or presentation. Abraxas3d also mentioned some interesting findings from the ITA conference, but decided to wait for others to discuss their work before sharing these. Rick provided an update on his Deep Space Engineering Society (DSES) engineering meeting, mentioning the progress on the building and the upcoming Earth Venus Earth contact. He also discussed a potential issue with the link margin and suggested possible solutions.
