Thanks for the info!

It might be helpful to know a few things:

-what is the expected duration of the mission?

(extreme short-term might make SSTV or FM/voice more attractive)

-what is the expected orbit?

(satellites that are only in-range of a small number of operators should carry whatever is most useful to that group)

-is more than one capability possible?

(we're seeing some recent satellites with the capability of multiple downlinks or the ability to switch between various modes)

Thanks!

-Scott, K4KDR

=========================================

-----Original Message----- From: Andrew Glasbrenner via AMSAT-BB Sent: Tuesday, October 29, 2019 2:00 PM To: [email protected] Subject: [amsat-bb] Secondary mission ideas

I just had a super call with a university program flying a mission using SDRs. We talked about licensing and coordination issues, and discussed ideas for a secondary two-way mission that they want to do.

What would you like to see, repeater, transponder, BBS, digital voice, digipeater? Downlink would be on 2m, and would probably be limited to 20-25khz wide. Other ideas? Something new and different? Let's have a civilized discussion about what they could try, as they seem to be an eager and capable bunch.

73, Drew KO4MA

Something new then. Voice mode sounds good. But allow VARA SAT OFDM up and down into a Winlink RMS. VARA SAT is slowed down with increased latency, to enable the sat delay ARQ. They have this on QO-100 already. Should be a challenge with Doppler.

Bernard, KC9SGV.

Sent from my iPad

On Oct 29, 2019, at 1:14 PM, Robert Bruninga via AMSAT-BB [email protected] wrote:

Voice mode but with embedded CALL and GRID data, so we can see who is calling where., and maybe a few bits for Station type. (handheld, portable, mobile, Oscar,etc)... Bob, WB4APR

-----------------Original Message------------------ From: Andrew Glasbrenner via AMSAT-BB Sent: Tuesday, October 29, 2019 2:01 PM Subject: [amsat-bb] Secondary mission ideas

I just had a super call with a university program flying a mission using SDRs. We talked about licensing and coordination issues, and discussed ideas for a secondary two-way mission that they want to do.

What would you like to see, repeater, transponder, BBS, digital voice, digipeater? Downlink would be on 2m, and would probably be limited to 20-25khz wide. Other ideas? Something new and different? Let's have a civilized discussion about what they could try, as they seem to be an eager and capable bunch.

73, Drew KO4MA _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb

Idea 1: Crosslinks Something (anything) with crosslinks...... Big goal would be to go for DX records via intentional crosslinks for voice/packet/telemetry/(maybe even telecommand) relay.

If there is a tunable uplink frontend, (and its allowed from a regulatory perspective, so maybe fixed downlink freq, tunable uplink freq)....You mentioned 2m down, so my guess is UHF up? Idea would be to relay voice/packet/maybe TLM from birds with a UHF downlink....Maybe go as far as regenerative transponder instead of bent pipe....easy enough for FM on a 'single frequency' (in quotes because Doppler...) could be trickier if single sideband relay and there are multiple signals in the passband. So maybe regenerative for FM relay and/or packet relay, bent pipe for sideband relay.

......and if its tunable, it could be changed around 'seasonally' as orbits change and the chances of a relay increase or decrease for a particular bird. Another fun application could be helping 'hurt' birds.....maybe something up there is still transmitting, but the finals on the PA are blown......if you could get a receiver close in.....maybe it could hear it and relay the data.......

Same idea for birds with hurting RX if they could tune their 2m downlink around (but that's probably a tougher sell from a regulatory point of view). Imagine if they could TX at UHF (I know they can't, just an analogy here...). Tune to 435.300 MHz......get in 'close' to Fox-1C, and relay a couple of command station commands via a bent pipe transponder.. might be an interesting experiment and stimulate some kind of response from Fox-1C (Just an example, I know the up/down freqs are inverted for 1C, but it gets the idea across)......basically: Drew's house------(UHF up)----->(UHF RX) Their bird, bent pipe (VHF TX)---> (VHF RX) Hurt Bird.

When 1E launches (VHF Up, UHF Down).....could make for some fancy fun.........relay the 1200 bps tlm via their bird......or make voice contacts back and forth between the pair of bent pipe transponders.....or maybe do both at the same time.........Depending on orbits and such, this could make tuning for Doppler fun with multiple hops and different bands in the mix.......sometimes you might have to tune UP on the downlink.

Idea 2: How 'utilized' are the Amateur Satellite Service bands? Different idea could be spectrum mapping.......depending on the type of SDR, if they can receive the full 3 MHz of 435-438 MHz band....do some FFT/averaging magic, store off FFT 'snapshots', and then later downlink the snapshots. Idea would be to develop a 'heatmap' of the use of the 435-438 MHz band. Doesn't have to be hyper-precise geolocation or anything that crazy to still to be useful......as long as they manage a reasonably accurate timestamp for when the FFT was taken (preferably in UTC, or at least something that can be mapped to UTC) they could figure out where the bird was from TLEs later. If they happen to be flying a GPS, even better. Global heatmap of the 435-438 MHz band might be good info for groups like IARU for coordination purposes.

Idea 3: Simple software defined transponder Do thing like the SDX from ARISSat-1 days. Basically a 'plain old' bent pipe transponder, but with things like power normalization from uplink to downlink so everyone gets an equal share of downlink power (LEILA). If a 'violator' exceeds uplink limits for too long, send them some CW on their equivalent downlink freq telling them to turn down the juice. Another one I would love is FM up, SSB down.......would let me use my TH-F6A for QSOs (or any other HT that can TX FM, and receive all-mode). Another mode under this category could be a basic APRS digipeater. The novelty is not doing the basic things individually, it would be being able to change modes from one to the next to the next with the same software radio running different waveforms (one day they're making heatmaps, the next they are an APRS repeater, the next they are an FM repeater, the next they are an SSB transponder with power normalization, etc. etc. etc. ).

Good Stuff!

-Zach, KJ4QLP

The AMSAT-ID usage of IO-86 for scouts, etc. brought to mind another use of the proposed payload. What if it was possible to build in a STEM aspect such the usage of the FUNcubes which are planned for use by education programs during the day - and, then available for amateur radio usage when the satellite is in eclipse (assuming there are no school kids since it's before or after school when it's dark outside).

Of course that means that besides the engineers and operations people getting the satellite up there we'd need folks on the ground to create the STEM mission. I've heard of a future AMSAT Youth Initiative on the table and this might be a platform for that program to take off ... so to speak.

-- 73 de JoAnne K9JKM [email protected]

On Tue, Oct 29, 2019 at 8:19 PM Leffke, Zachary via AMSAT-BB [email protected] wrote:

Idea 2: How 'utilized' are the Amateur Satellite Service bands? Different idea could be spectrum mapping.......depending on the type of SDR, if they can receive the full 3 MHz of 435-438 MHz band....do some FFT/averaging magic, store off FFT 'snapshots', and then later downlink the snapshots. Idea would be to develop a 'heatmap' of the use of the 435-438 MHz band. Doesn't have to be hyper-precise geolocation or anything that crazy to still to be useful......as long as they manage a reasonably accurate timestamp for when the FFT was taken (preferably in UTC, or at least something that can be mapped to UTC) they could figure out where the bird was from TLEs later. If they happen to be flying a GPS, even better. Global heatmap of the 435-438 MHz band might be good info for groups like IARU for coordination purposes.

More data can't hurt but this has already been done:

https://marconissta.com/uber/

73, John Brier KG4AKV

I love the idea, Cathryn, but it needs to have some mechanism to prevent someone(s) from continually uploading an image or images, filling the queue. History with the ISS and unattended stations beaconing incessantly for apparently vanity purposes to show up on the "Stations Heard" site suggests that this Commons resource could be tragically made inaccessible to most. Also need to have some way to securely link an image to a call sign, so that inappropriate content can't be uploaded anonymously.

But, with those measures in place, I think it would be a great way to bring in the larger community, and see what's going on in Ham Radio around the world. Basically, it's a regular store-and-forward BBS system with a dedicated message type (image), and an on-going download similar to the ISS Slow Scan TV events. I can imagine someone lashing up an SDR receiver and an electronic "picture frame" to display a rotating image from space.

Greg KO6TH

Cathryn Mataga via AMSAT-BB wrote:

My pitch, store and forward tiny images. The receiver listens on the receive channel 9600 baud for digital images. It just listens only. Whenever it receives one with proper headers and without error, it stores it. Then on the downlink, it cycles through the last 20 or so, or about however many can be downloaded in an overhead pass. When the 21st picture comes in, it just throws away the oldest image. I suggest using .png formatted graphics with a file size limit of 8192 bytes, something like this? Enough pixels to be fun, but not so much to get unwieldy.

This would make a fun visual demo to show off amsat/ham radio -- the satellite would show a cool little slide show from stations around the world.

---

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On 10/31/19 1:28 PM, Zach Metzinger via AMSAT-BB wrote:

On 2019-10-31 15:10, Greg D via AMSAT-BB wrote:

...

Also need to have some way to securely link an image to a call sign, so that inappropriate content can't be uploaded anonymously.

This may be going way too far for a hobby. What's next, fingerprint or biometric data before I'm allowed to turn on my HF rig and transmit a picture across the world via SSTV?

Digital signing images could work, but this stuff takes care to do correctly and a mistake would defeat all the effort. If someone wants to design a 'satellite login' system where we verify our Callsigns "Logbook of the World" style, and then have private keys to verify our identity, well, that's another project, and best if shared among all future satellites that want to use it.

I suggest an open command to delete any image.  The images would fall off the queue anyway eventually, so not much is lost if someone gets delete happy.

I'd like to offer my opinion on this topic, everything that follows is IMHO:

First off.....should we start a separate thread for a conversation on digital signatures / identification in Amateur Radio? Hopefully this isn't distracting too much from the main point of the thread for helping to collect up secondary mission ideas for Drew and the potential new partners. I'm saying that, because I'm about to dilute the thread with my opinion on digital signatures (hi hi), and feel bad that I might be distracting from the main point (long emails......but this stuff is just too cool)......

I'd like to voice my support for the concept of digital signatures for this type of concept of operation (CONOP) for an Amateur Radio spacecraft (but not all satellite CONOPs).

This type of operation is probably coming one way or another as technology evolves with the introduction of more advanced payloads to the hobby, depending on mission needs......and the sooner we can start trying it out, and trying to make it easier for hams to use (for the implementers out there) I think is a good thing. I think I can see both sides of the coin here.....and I think the trick is the devil in the details and in the method of 'enforcement'. Amateur radio has prided itself on being a 'self-regulating' entity, and for Zach's example, I would argue that there are mechanisms in place such as the ARRL Monitors Program that work with the FCC to potentially self-correct misconduct within the service or escalate 'flagrant violations' to the FCC. For a satellite, that method of enforcement is much more difficult.....and the methods used to identify an illegal/inappropriate HF station simply wouldn't work for the image upload CONOP. Something like a digital signature mentioned by Cathyrn is one way to create that type of capability for a spacecraft. There is a delicate balance that needs to be struck between ease of use if you want folks to operate with something new, but control is also very important.

When we were working on the GEO (Phase4B) payload back when there was more momentum, this specific issue came up for controlling user access to the digital transponder. Remember that one of the main mission objectives was emergency communications. Authentication of a user was very important for this, especially for prioritization of satellite resources and availability. Some folks may remember talk about 'emcomm mode' vs. 'anyone can play mode.' One idea for what one of the differences between those two modes would be is whether or not users are being authenticated and allowed access to the bird. In one version of the idea, when in EMCOMM mode, a 'whitelist' of authorized users would be allowed to use transponder resources, those users specifically involved in the emcomm event that needed the transponder. There were even discussions about whether or not we should *always* authenticate users, because with a 24/7 GEO resource....well, put simply, satellite piracy is a real thing, and we need a mechanism to deal with it.

Without getting bogged down in the technical details of that particular GEO attempt, I just wanted to say we specifically considered Log of the World for the mechanism for generating the credentials to identify a user. Having a single certificate authority for all things 'Ham Radio' is a good idea so that users only have to create their identity 'once' and not have to keep doing it for each new mission....LoTW is something that many hams are 'used to' and is something maintained at a central place familiar to hams. Its seems like the 'easiest' way to get folks to 'register' for the ability to access the satellite. Yeah, its an additional step to get on the air...but hopefully one most have already taken, and one that's not hard to take for those who haven't, and the payoff for taking the step is access to a really cool new capability! In this way, we have the ability to lock out illegal operators (that may not even be licensed Hams) and/or inappropriate users, and a way for us to prioritize use for EMCOMM situations......very important if lives are at stake.

There's a lot more detail behind this for the ideas around how the authentication process would actually work that I won't get into.....no actual decisions were made, but a lot of really really good conversations about how to ensure we can control the resource and keep it open for use to as many hams as possible with the least amount of burden (for the user, not necessarily least amount of burden for the designers/control operators), maximize it's utility during EMCOMM events, and not run afoul of FCC either through illegal/inappropriate use of the resource that we are unable to 'self-regulate' against but also make sure we don't run afoul of them in the way we implement the solution (authentication conversations can sometimes turn into encryption conversations.....no go for Amateur Radio, but all ideas are good ideas when brainstorming a solution to a tough problem). Basically, we wanted a way to remove the bad apple from the bag, rather than spoil the bunch (i.e. turn off the whole system) because we didn't have a way to deal with the bad apple.

Summary: I think the digital signature idea is a good one, I think LoTW is a good candidate for the certificate authority, and I think considering this type of operation within the constraints of part 97 rules when implemented helps set us up to keep our spectrum and keep it 'self regulated' as technology evolves.......and the sooner we start testing/demonstrating these capabilities, the better off we are.

Again, all above is IMHO.

Sincerely, -The 'other' Zach, KJ4QLP (N0ZGO is the main 'Zach' because he's getting it done on Golf!)

P.S. To be clear, I do NOT think we need this type of thing for every type of Amateur Radio communication or even every future satellite.....for the image upload example, and the GEO example, I think it makes sense at least in terms of one option to consider for a solution......there could be other solutions to the issue.

I also like this idea a lot. One 'desirement' after having AO-92 up for a bit with our Camera was I wish we had built in a way to time when the shots were taken. Right now its take a shot, downlink, rinse and repeat (about as simple as it gets). No onboard storage and it immediately starts taking pictures when kicked into that mode. So for your #2, if you add in the ability for the uplink command to control when to take a picture (or delay X number of seconds from command receipt) that could be really cool so that the images are not always the same 'regions' of Earth near command stations (especially considering it might only be a single command station if it's a University controlling the bird). I would also say do something like take 5 pictures, spaced X number of seconds apart, store them, and then downlink them over and over when in high speed/power mode. All of that control could probably be fit into a single camera uplink command.......in X seconds (or at X time if they have absolute timekeeping), take Y number of pictures (maybe Y in the range of 1-10 or so), spaced Z number of seconds apart......

-Zach, KJ4QLP

-- Research Associate Aerospace & Ocean Systems Lab Ted & Karyn Hume Center for National Security & Technology Virginia Polytechnic Institute & State University Work Phone: 540-231-4174 Cell Phone: 540-808-6305

-----Original Message----- From: AMSAT-BB [email protected] On Behalf Of Wendy and Terry Osborne via AMSAT-BB Sent: Thursday, October 31, 2019 10:38 PM To: Andrew Glasbrenner [email protected]; [email protected] Subject: Re: [amsat-bb] Secondary mission ideas

Here are a couple of ideas. 1) A Funcube type transponder but with an L-Band Uplink. This would give an easily decoded telemetry downlink for STEM demos etc. This combined with an L-Band uplink would give a linear transponder to complement the FM transponder on AO-92.

2) An on board camera that could be aimed at the earth and store the resulting picture. The camera could be triggered by a command station(s) and downloaded (in jpg format?) when the transponder was in high power telemetry mode. This would be a great educational tool.

73, Terry Osborne ZL2BAC

-----Original Message----- From: Andrew Glasbrenner via AMSAT-BB Sent: Wednesday, October 30, 2019 7:00 AM To: [email protected] Subject: [amsat-bb] Secondary mission ideas

I just had a super call with a university program flying a mission using SDRs. We talked about licensing and coordination issues, and discussed ideas for a secondary two-way mission that they want to do.

What would you like to see, repeater, transponder, BBS, digital voice, digipeater? Downlink would be on 2m, and would probably be limited to 20-25khz wide. Other ideas? Something new and different? Let's have a civilized discussion about what they could try, as they seem to be an eager and capable bunch.

73, Drew KO4MA

_______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb

_______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb