Dreamcatcher v3.02: Feedback Thread

Konrad,
I thought you already had the latest DC. Mine might come Friday also.
Don

Great - - in looking at the Apps in Skylark, I think most of them are self explanatory, but Messages and Weather could use an in depth explanation. By in depth, I think you’ll need to think about taking a user from 1 + 1 = 2 (like me - - a non radio amateur operator) thru to the end.

A good case in point (not really Set Up oriented) was a recent question about how to print a news panel. Well, I never thought to do that, so I didn’t have to figure it out. But the answer seems so reasonable, I would never have guessed it. Ken

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Mine is on it’s way. FEDeX should deliver it tomorrow.

–Konrad, WA4OSH

Some don’t work … that’s another discussion we still need to have.
It’s hard to do this without seeing the design document …

Here’s what I’m going to put together to document my issues.

Title:
Summary:
Steps to Reproduce:
Expected Results:
Actual Results:
Severity:
More info:

–Konrad, WA4OSH

I would aloso love to see how much useful data you can cram in the current ku band link. I wonder if the new attenna that @Syed is working on is going to have a way to be like a some what Omi attenna via like being a golf ball in shape. Then a moble outernet setup becomes possible.

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Improved? Wow. Scared to see what it looked like back then. The barely usable, hideous, web site gives me a mix of flashback to Prodigy and Banyan Vines.

-liam

Tylerhoot,
I don’t think we’ll see an “Omni” antenna that you can just aim anywhere and sniff the air for Ku. The cone needed at my location is a testament to the fact that we need more gain than a bare LNB can offer in some places like Seattle where the coverage is not perfect.

I think a mobile solution is very possible, but it’s going to require a bit of antenna ingenuity to be quite candid.

–Konrad, WA4OSH

If anything, it would be a hemispheric antenna for a mobile receiver. At 6 dBi, we already have a patch that is pretty close to that, but using that antenna requires the spreading to increase and bitrate to decrease. Konrad is correct that we will be going higher gain. A tentative target is around 18 dBi.

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Look at what came to the house a couple of hours ago. I can’t set it up for a few more hours though. :frowning:

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Where are you located? I’m wondering if you’ll be able to receive without a DIY cone

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Louisville, KY

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I’d love too see a planned experiment that varies the SF for day or two and demonstrates the impact. Maybe the Skylark can be programmmable with a schedule that varies what the carousal is transmitted for a couple of hours each day? and allow “marginal” signal users to get some of the content during times of high SF and low bitrate.

that would still be cool to see a good setup for a mobile attenna

Have you looked into sending two signals at once the way they do it with LoRaWAN gateways? The two signals would be mostly orthogonal except where they come close to crossing. One signal carries a lower data-rate stream and the other stream carries the higher data-rate stream. The mobile users could opt for the lower-rate stream while moving and when they become stationary could switch over to the standard rate stream.

lpwan-london-meetup-solving-urban-challenges-4-638

What is the cost in using the mobile data stream? Fewer articles or some data not being sent at all.

–Konrad, WA4OSH

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Excellent idea. maybe early morning etc.

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What about 30 Milliseconds slow data rate (big spread) and then 30 Milliseconds fast data narrow spread sent down from the satellite.

Now if we multiplexed dynamic time sensitive, data ie Voice, news, weather etc into slow data time slot at 30ms intervals then mobile and Fixed Dreamcatcher users could receive all the Dynamic data.

Heavy data like Video clips , Wikipedia feeds, books etc could be multiplexed into the Narrow spread fast speed data and be received by Fixed Dreamcatcher systems.

A 30ms slow data rate multiplexed in with a 30 ms High speed data rate should allow voice etc messages to be received by both Mobile and Fixed Dreamcatcher units,

@Seasalt I think you captured this concept. I can only hope it is possible. I like the idea of both mobile and fixed users being accommodated.

You do understand that both streams can be sent at the same time on top of each other without interfering with each other, right?

–Konrad, WA4OSH

That by it self may allow more data to be moved overall that’s if the recever half can manage 2x data streams at once

One small, but important detail. The two streams have to have different spreading factors so that the streams are “Orthogonal” to each other.

7.1. LORA Modulation
The radio settings available for LORA modulation are: - The Frequency (Freq) as described in Section 7.5

  • The Transmission Power (Tx Pow): in steps of 1 dBm between -18 dBm and
    +13 dBm
  • Param 1: choose a Spreading Factor between SF5 and SF10
  • Param 2 : choose a BandWidth (BW) of either 400 kHz, 800 kHz or 1.6 MHz
  • Param 3: The Coding Rate (CR) of the Forward Error Correction applied to
    the packet, of either CR 4/5, 4/6,4/7, 4/8 or CRLI 4/5, 4/6, 4/7
  • Payload: size of the payload between 12 and 248 bytes

I don’t know where these parameters (SF, BW, CR, and Payload) are set. But we do know that the current modulation uses 1.6 MHz. In order to increase the process gain, we would need to maximize SF, decrease BW and increase CR/FEC. But if SF10 is already being used, the SF for the other carrier would have to have a different SF.

–Konrad, WA4OSH