QoS: Call for Input

We’re moving into the challenge of multiplexing on the transponder with a goal of delivering Quality of Service (QoS) metrics and policies.

This is “how do the uplink packets get properly prioritized on the downlink, to make the most of limited resources”.

These resources are spectrum, power, and time.

QoS doesn’t make any of our communications channels go faster. This is a common misconception about QoS. Here’s some descriptions from conversations this week. I would like to hear more opinions about QoS in general, and any specific requirements that people on this list might have.

Kenneth Finnegan writes,

“In #networking it’s common to forget that QoS is mainly about deciding which packets you’d rather drop first.

If you don’t like that idea, then you just need to pony up and throw more capacity at the problem.”

Adam Thompson continues,

“In the presence of a pizza that’s not big enough for all the hungry people, QoS inhibits less-important pizza eaters. This lets more-important eaters-of-pizza get more pizza than their fair share, at the expense of the less-important eaters.

“In the presence of a pizza that’s not big enough for all the hungry people, QoS inhibits less-important pizza eaters. This lets more-important eaters-of-pizza get more pizza than their fair share, at the expense of the less-important eaters.

QoS never (ever!) makes the pizza bigger – if you need more pizza, you must still bake or buy more, or someone’s going to go hungry!

Complex QoS systems might let you differentiate between e.g. crust and topping and permit cutting the pizza into bizarre topographies/topologies, but still can’t make the pizza any bigger.

Finally, if there is enough pizza for everyone, QoS doesn’t do anything useful.”

If this last part sounds familiar, then you’re not alone. QoS often doesn’t do anything useful… in a resource rich environment. This may be the main reason that we sometimes hear that QoS is a “failure”, that it’s “never used”, or “why bother for hams since hams don’t care about this subject at all”.

It is true that most amateur communications are made with acres and acres of spectrum, with a very generous power limit (although you are supposed to use the minimum required power) and no time limits on how often you can try to make a contact.

When we talk about microwave broadband digital communications, it’s a different situation. And, with space channels, there are constraints. We have less bandwidth to work with because we’re on a sub-band. We have latency, which is non-trivial for GEO or beyond. We have power concerns and pointing requirements.

“Adaptive” QoS that does nothing until congestion forces some decisions, at which time we sort with respect to SNR, has been our baseline.

What we want to do when constraints are hit is what we need to better define. Right now, we have a whiteboard design (summarized above) and a paper about Adaptive Coding and Modulation (ACM) that was published in AMSAT-DL and AMSAT-UK Journals.

We have the implementation guidelines from GSE as well, which address QoS and show how to set up queues.

With a controllable downlink going out over the air, and a defined uplink protocol, now is the time to work on exactly how to multiplex the traffic. Evariste asked about this exact thing less than a week ago at the FPGA meetup.

Decisions about QOS heavily affect the central part of the design, so let’s get this right.

Do you have experience implementing QoS policies? Do you have experience with bad QoS policies as a consumer? Do you have an idea about what you want to see this design do?

Well, you’re in the right place, and we’d love to hear what you have to say about it.

Participate at https://openresearch.institute/getting-started

ORI participation at OSCW 2021

Recording, transcript, and slides of Open Research Institute’s presentation at Open Source Cubesat Workshop 2021.


Hello everybody! I’m Michelle Thompson W5NYV and I’m here to tell you all about what Open Research Institute is and what we have been doing.

Open Research Institute (ORI) is a non-profit research and development organization which provides all of its work to the general public under the principles of Open Source and Open Access to Research. As we all know, these mean particular things, and those things have to be defined and they have to be defended.

Open Source is type of intellectual property management where everything you need to recreate or modify a design is freely available. As a baseline, we use GPL v3.0 for software and the CERN Open Hardware License version 2.0 for hardware. All we do is open source work, primarily for amateur radio space and terrestrial, but also some other fields, as you will see.

So who are we?

Here is our current board, and our immediate past CEO Bruce Perens. We have one opening on the board, as Ben Hilburn, one of our founders, very recently retired from being an active Director at ORI. He remains as one of our senior advisors. We are looking for someone to join ORI board that supports what we do and wants to help make it happen. It’s an active role in a flat management structure. Board members are are experienced in management, engineering, operations, and technology, and three out of the current number of four are from underrepresented groups in STEM.

As a board, it is our mission to serve our participants, developers, and community members. We now have at least 535 that participate in what we call the Open Source Triad: our mailing list, Slack, and GitHub. All work is organized in independent projects or initiatives.

We have some affiliations and we proudly ascribe to the Open Space Manifesto from Libre Space Foundation. We work with radio organizations, several universities, and have worked with a variety of for-profits.

What do we do?

Here’s a visual summary of top level projects and initiatives. The vertical axis is risk. Higher risk projects are at the top, lower risk projects are at the bottom. Maturity increases left to right. Maturity may indicate schedule, but the score is also influenced by complexity or difficulty. The color of the shape indicates how much stress that project is under or what the risk level is at this time. The size of the shape is the budget estimate. By far, the largest budget, riskiest, and least mature work is in the AquaPhage project, which is open source bacteriophage research and development. Bacteriophage are viruses that attack and destroy bacteria. This is biomedical and not amateur radio. This project was halted by COVID and has not yet resumed.

Our digital multiplexing payload project is called P4DX, and it’s in the middle in green. This is a multiple access microwave digital regenerating repeater for space and terrestrial deployment.

Channels divided in frequency are the uplink. The uplink is on 5 GHz. The processor on the payload digitizes and multiplexes these signals and uses DVB-S2/X as a single time-division downlink. The downlink is on 10 GHz. The system adapts to channel conditions and handles things like quality of service decisions. For example, low and high latency digital content. The uplink is divided up using a polyphase channelizer, based on the open source work done by Theseus Cores.

For the current prototype, we are only using MPEG transport stream, but generic data is the goal. The prototype beacon signal is 5 MHz wide and we are using one modulation and one error coding (yet). We are not yet rotating through all the allowed combinations in DVB-S2 (yet).

Our prototype work can also serve as a terrestrial multimedia beacon. Work was demonstrated to groups with mountaintop spaces in October 2021, and deployment will be as soon as possible.

M17 project is an open source VHF/UHF radio protocol. Think open source digital mode HTs and repeaters. This project is only slightly more stressed than P4DX, but it’s further along in maturity because it’s narrower in scope. We believe M17 Project will be very successful from current development to scaling up to commercial product launch. The M17 protocol is the native digital uplink protocol, with some modifications for 5GHz, for P4DX. We are working hard to get M17 on and through more satellites and more sounding rocket tests today.

Engineers General is our initiative to hire highly competent open source workers to reduce burnout and increase quality in open source work important to amateur radio. We have one contractor currently, eight resumes, and have applied for funding for two more. We are actively looking for funding for the remaining five.

The “birdbath” is a large dish antenna at the Huntsville Space and Rocket Center. This was used in the past, but has been parked for decades. It took two years of negotiation, but ORI has the support of the museum and permission to begin work renovating this dish for citizen science and amateur radio educational use. Work parties from earlier this year were rescheduled due to COVID.

Upper right there are two completed projects. One is ITAR/EAR Regulatory Work. It took over a year, but we received a determination from the State Department that open source satellite work is free of ITAR, from Commerce that it is free of EAR, and we obtained an advisory opinion that publishing on the internet counts as publishing under the regulations. This is a huge step forward for not just amateur radio, but anyone that wants to contribute to open source space work.

Debris Mitigation Regulatory Work took 10 months to complete. The process culminated in a highly successful meeting with the FCC Wireless Telecommunications Board, the Office of Engineering Technology, and the Satellite Bureau in late October 2021.

Lower right is Battery Matching, a project that matches NiCd cells for very durable batteries in the style that used to be done in amateur satellites, and puts the methods and documentation in the public domain.

AmbaSat Inspired Sensors used to be on the bottom right but now it’s bumped back a bit in maturity level is higher risk. This was supposed to be a project done by students at Vanderbilt university, but no students materialized, primarily due to COVID. We had one kick-butt professional volunteer who was working on a 10GHz beacon that went into the sensor connector on the main board, but the project was moving slowly, and ORI decided to provide additional operational support. Additional volunteers joined the team, we reviewed the finances, and then took some actions. We updated the main board to move it from the illegal ISM band it was in to the legal 70cm ham band. We improved power and ground and addressed some other design concerns. The boards are back as of last week and software and firmware development is underway. The 10 GHz sensor “beacon” work is proceeding quickly as well. AmbaSat is an excellent educational platform, but the ISM band decision isn’t the only problem with it. It’s very small.

We decided to look at combining the 70cm AmbaSat with another open source satellite board to make a combined spacecraft design. I reached out to Pierros Pappadeus at Libre Space, and we are moving forward with using the SatNOGS Comms project. We look forward to contributing to the FPGA codebase and flying both AmbaSat and SatNOGS Comms designs as early and as often as possible, starting with sounding rockets and ending up in space.

All of these projects are open source and all work is published as it is created.

When?

We have timelines! We were incorporated in February of 2018, got our 501c3 in March of 2019, and we hit the ground running and haven’t stopped since.

We’ll distribute a copy of the slides so you can see our wins and losses along the along the way. There’s a lot going on in here.

Here’s what’s been going on since March, and the future plans we know about.

We use Agile framework for management, and most of us have some sort of formal certification either completed, or in process. This is the Agile manifesto and it is the foundation of how our board decides things and how it supports project leads and volunteers. Note the second item, and put in the word hardware instead of software, and that’s one of the reasons we demonstrate early and often and incorporate the feedback quickly.

Where are we?

Here’s the locations of the concentrations of current major contributors and participants. When we say international, we mean it. Our participants have a wide range of ages, are generally educated in engineering, come from a variety of backgrounds, but do tend to be relatively young and male.

We have some physical locations that are important for carrying out the work we do. Remote Labs are lab benches connected to the internet that allow direct access to advanced lab equipment and two different large Xilinx development boards and DVB-S2/X gear. We have relocated our second Remote Lab equipment from Florida to Arkansas, and have added a three-dish interferometry site for amateur radio and public science use. Remote Labs are here for you all to use. If you need large FPGA resources and test equipment up to 6 GHz, then we have your back.

We bought Open Lunar Foundation’s satellite lab. It’s in storage waiting for the M17 project lab construction to conclude, and then the equipment will go there to pack that lab full of wonderful test equipment, materials, and supplies.

Why do this?

We believe that an open source approach to things like amateur digital communications, bacteriophage research, and sticking up for the non-commercial use of space will result in the best possible outcomes for the good of humanity.

We have a lightweight agile approach to doing things. We keep our overhead very low, we are radically participant-focused, and the work must be internationally accessible.

You can see that public demonstrations and regulatory work are given a high priority. Working code and working hardware are highly valued. Working means working over the air.

Thank you to everyone at Libre Space for the support and opportunity to present here today.

https://www.openresearch.institute/wp-content/uploads/2021/12/OSCW-2021-W5NYV-ORI-1.pdf

P4XT (Phase One) Workshop Design Review

Learn about our work on the digital microwave broadband transponder for amateur radio.

https://www.youtube.com/watch?v=QXiWCgo10lg

All work is donated to the general public as open source.

This digital multiplexing transponder is a regenerative design, taking full advantage of a wide variety of cutting edge technology, intended for amateur radio use in space and terrestrial deployments.

This review focuses on decisions made for the prototype board set that implements the transmitter side of the payload.

Comment and critique welcome and encouraged.

Floating Vivado License for FPGA Work Purchased – Will be Available for Community Use

Thanks to the generous support of Yasme Foundation, ARRL Foundation, and many individual Open Research Institute supporters, ORI has purchased a full floating Vivado license for FPGA work. This includes the System Generator for DSP.

We are testing a setup that will make team and community use of this license possible. This is a big step forward from our current situation and will greatly accelerate FGPA design and test.

The first step was setting up a license server at a donated data center. Many thanks to Nick KN6NK for offering the time, resources, and expertise to get this working.

The second step, being tested right now, is using GitHub as a directory service for adding users and keys.

The goal is for users of the license to be able to add themselves with minimal admin overhead while asserting some reasonable control over access.

GitHub provides a way for users to get public keys. The work required of us is to script user management and periodically sync key management.

Thank you to EJ Kreiner for helping test and refine this community asset. We anticipate being able to support as many amateur technical communities and projects as possible, to get the greatest possible use from the license.

Special thanks to ARRL and Yasme. We would not be able to afford this investment without their support.

FPGA iCEBreaker Workshop – digital communications for amateur satellites

Greetings all!

Field Programmable Gate Arrays (FPGAs) are one of three fundamental types of digital architectures used for communications R&D.

The others are general purpose processors and graphical processing units (GPUs).

This fall, in San Diego, California, there will be an FPGA course sponsored by Open Research Institute. There are 10 spots with amateur communications as the focus of the work.

FPGAs are a primary technology in satellite communications. They’re used in R&D and in deployment. It is difficult to get started with FPGA design for several reasons. The tools have traditionally been proprietary. The companies that make the tools price them for large corporations to buy. Coursework for FPGA design is rare.

This is where iCEBreaker makes a difference.

An iCEBreaker Workshop 10 pack has been made available. They are described at this link https://www.crowdsupply.com/1bitsquared/icebreaker-fpga

I will use this hardware to put on a course for anyone interested in amateur radio satellite and terrestrial development. All course materials will be published.

The first course will be in San Diego. If you’re in the area, please get in touch! MakerPlace and CoLab are the likely sites.

Later workshops could be at places like Symposium, Xenia, or Hamcation. The full course cannot be accomplished in a day, but a workshop could get the basics across and provide a substantial boost to motivated amateur satellite engineering volunteers. Let me know what you think.

more soon!
-Michelle W5NYV