Yes there's plenty of difficulties with home-grown devices. Fortunately most people aren't capable of designing an over-the-air protocol like lightbridge, and there's a limited selection of chips to choose from.
Interesting. Does our product not seem simple? We're working on some fancy mesh protocol stuff for making DIY projects easy, but those features don't have to be enabled at all. You definitely could use this just like an arduino with a radio attached, we'll have full libraries for sending data to any device directly, and our code will have copyleft licences (thinking GPL, haven't decided yet) and we will encourage forks.
You can look at them as basically just compute and radio modules - they can be used however you'd like!
Thanks! Say I wanted to transmit, what’s the general process for navigating the minefield?
One of the things I’d like to do is build a software-defined radio (using an rpi, for example) and use it to send something like Ethernet packets over the air.
* Nordic nRF51/nRF52 - Very good option. Completely documented. You can do custom radio protocols. Very popular.
* TI CC2650 - Looks good. Apparently fully documented. Unlike the Nordic chip it has a separate processor for the BLE stacks so your code doesn't get interrupted during connection events. Also supports IEEE 802.15.4. CC2640 is BLE only.
* Samsung Artik 1 - BLE only; looks expensive
* Intel Curie - I don't know much about this but apparently it isn't well documented.
Wifi and BLE:
* Intel Edison - Powerful but very expensive
* Artik 5 - Again, powerful but expensive
I'm not really aware of any other solutions that have:
ICs are not the problem, this can be decoded with a soundcard within the pc... usually the antennas are more problematic, atleast for urban areas, because you need 2x5.5m long dipole to use those frequencies (13mhz), so doing it in dense, urban enviroments is hard (unless you have roof access).
Otherwise, with lora and a lot shorter ranges, you can create mesh communication networks easily, with $20-$30 of hardware (already assembled) - eg. https://meshtastic.org/
eCPRI, or essentially radio signal over ethernet (ie. from base station indoors to radio module at top of the tower/roof) is another interesting use case (with even stricter latency requirements than audio).
Pretty interesting perspective - maybe check out the Hologram Dash which is programmed with the Arduino IDE + has full compatibility with Arduino functions. It includes a cell modem as well: https://hologram.io/dash/
I'm going to use Java, the tricky parts will be to build the frequency hopping (for me 410-525MHz) + power lowering (-1-+14/+20dBm) parts so that densely populated areas can function properly.
I'm curious what the fundamental underlying tech is that is driving Lora and Sigfox? E.g. cdma has a few core ideas that make the magic work. What is the equivalent fundamental concept that is driving the low-power, long-range, low-bw communication?
Nice hack! I wonder what other useful common digital signals can one record with a dongle? Time and date, teletext (which includes weather forecasts and news) I am aware of. There is also project Lantern & Outernet which might deliver 20 MB of data to all continents through nanosats next year. What other digital signals are transmitted?
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