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How New Long-Range Radios Will Change the Internet of Things

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Re: How New Long-Range Radios Will Change the Internet of Things

#51

Post by CamperBob2 »

jazzyk wrote: post #17
blhack wrote: post #13

This is un. fucking. real. I work in the IoT space (specifically on health devices), and something like this would be absolutely a GOD SEND for the things that we're doing. The current "hottness" in our space is bluetooth low energy (BLE). This is super low power (or, rather: chips that are really good at going to deep sleep, and then coming online very quickly to burst some data out), but the range on BLE isn't grea…

Cool stuff, sure. But, in my opinion, IoT will be slow to take off until the security aspect is solved - and it is a tough one.

I can't think of any other technologies that have waited for the security aspect to be solved, can you?

Re: How New Long-Range Radios Will Change the Internet of Things

#52

Post by blhack »

0898 wrote: post #50
blhack wrote: post #13

This is un. fucking. real. I work in the IoT space (specifically on health devices), and something like this would be absolutely a GOD SEND for the things that we're doing. The current "hottness" in our space is bluetooth low energy (BLE). This is super low power (or, rather: chips that are really good at going to deep sleep, and then coming online very quickly to burst some data out), but the range on BLE isn't grea…

Just curious – why is range limited by a protocol? Why couldn't you send Bluetooth over hundreds of miles with a big enough antenna, for example?

Not limited by the protocol per se, but limited by the design requirements of BLE.

BLE; you're talking about power requirements of ~10mA transmit (current consumption), and averages in the Now: how LORA is accomplishing such crazy long ranges when supposedly consuming similar amounts of current goes a little beyond my understanding of RF. There are a few people commenting in this thread that seem to have the knowledge, though!

Re: How New Long-Range Radios Will Change the Internet of Things

#53

Post by olympus »

runeks wrote: post #32
kevinnk wrote: post #11

Earlier quoted context omitted.

Data rate in the US is something like 11kbps. So you'd have to be really patient.

Isn't 11 Kbps fine for SSH? That's 11 thousand ascii characters per second. The latency is the important part, I assume this is low as well but I don't know.

Actually each ascii character takes up a byte (8 bits). You can get this down to just 7 bits if you aren't using the extended table, but a byte is very convenient and what most programs use for the size of a char.

That means that with an 11Kbps line you are getting about 1,000 characters per second once you factor in other communication over head (stop bits, parity bits, etc). While this may sound fast it is painfully slow for anything other than typing in single line commands and reading single line responses. The transfer of a blank 4KB text file will take three seconds. The transfer of a plain text file the size of a book would take a few minutes.

With the additional overhead of SSH you will actually see the characters appearing on the screen like a lame 80s hacker movie.

Re: How New Long-Range Radios Will Change the Internet of Things

#54

Post by olympus »

semi-extrinsic wrote: post #49
th0ma5 wrote: post #2

Lower power, but highly processed radio signals are fascinating to me. I've been playing with WSPR on the 10 meter band which is fixing (hopefully) to open up a little here over the next couple of months. With about 1/10th of the power of my Wi-Fi router and a long wire over top of the house, I've been picked up so far this year in California from Ohio. Last year I was heard almost daily in Europe. A blogger I follow…

Ok, since there are some radio wizards in this thread: if I want to log low bandwidth sensor data (so < 1kbps) on a unidirectional (if that helps) link over ~ 500m, almost clean line-of-sight with some trees in there, what are my options? I'd prefer to spend little money and use little power on the sensor end. I'm considering an ESP8266 (so 802.11) with a high-gain directional antenna. Sender and receiver are fixed l…

Here are two low cost options (I recommend #1 for most people and #2 if you have an impressive beard):

1. The esp8266 like you have already mentioned. Get one with a u.fl connector and make your own cantenna to attach to it. You can use the microcontroller in the esp8266 to take the sensor readings (it even has an ADC to read analog sensors). This is the new hotness and there are tons of examples.

2. Even cheaper but less user friendly is a very low tech 433 MHz RF transmitter like you can get on eBay. You then need an external microcontroller to run it so you might actually be less cost effective overall and these things take quite a bit of effort to implement a reliable comm system because of the on-off keying system and zero built in error correction. There are libraries like VirtualWire or RadioHead that take quite a bit of pain away. You can get other frequencies if your country doesn't allow unlicensed 433MHz transmissions. Example of what I'm talking about: http://www.ebay.com/itm/like/140719918135?ul_noapp=true&chn=...

Re: How New Long-Range Radios Will Change the Internet of Things

#55

Post by kazazes »

dconrad wrote: post #16
jws wrote: post #3

I'm intrigued. Anyone want to suggest an economical development board or transceiver?

For LoRa, check out Multitech, LinkLabs, and Libelium. Semtech has a development board, too, though it would need to be paired with a microcontroller. Warning that most of this stuff is not for the faint of heart -- you need to be ready to dive into datasheets, bring up radio drivers, etc. For Sigfox, if you're not in an area with a Sigfox network, there's not much you can do. But TI has some killer FSK dev boards. h…

If you haven't lost your faith in Kickstarter yet, this project has $180k committed. A €40 pledge will get you a LoRa board and €200 for a LoRa gateway and what is essentially a demo dongle.

https://www.kickstarter.com/projects/419277966/the-things-ne...

Edit: fat thumbs, on mobile.

Re: How New Long-Range Radios Will Change the Internet of Things

#56

Post by marssaxman »

olympus wrote: post #53
runeks wrote: post #32

Earlier quoted context omitted.

Isn't 11 Kbps fine for SSH? That's 11 thousand ascii characters per second. The latency is the important part, I assume this is low as well but I don't know.

Actually each ascii character takes up a byte (8 bits). You can get this down to just 7 bits if you aren't using the extended table, but a byte is very convenient and what most programs use for the size of a char. That means that with an 11Kbps line you are getting about 1,000 characters per second once you factor in other communication over head (stop bits, parity bits, etc). While this may sound fast it is painfull…

It pretty much looked like that in reality, too.

Re: How New Long-Range Radios Will Change the Internet of Things

#57

Post by bertm »

jws wrote: post #3

I'm intrigued. Anyone want to suggest an economical development board or transceiver?

Try out Low Power Labs Monteino with the HopeRF, RFM95 LoRa module. The radio library is lacking but you can get up and running quickly. https://lowpowerlab.com

If you want something a little more enterprisy and turn-key, try the new guys (I work for them). The Patch module has both a BLE and LoRa radio. https://www.filament.com

Re: How New Long-Range Radios Will Change the Internet of Things

#58

Post by wyldfire »

slewis wrote: post #40
bdamm wrote: post #37

Don't get too excited. Low-power devices get really interesting when they start to scale up in numbers. None of the technologies listed in this article have demonstrated that capability. The coming IoT shakedown is going to leave quite a few ebullient "visionaries" crying in their martini while they consider their next startup. * Star networks are infrastructure heavy, requiring build-outs on part with cellular netwo…

Shawn from BeepNetworks here. Check out OnRamp (now Ingenu). Their coding scheme allows 1600 simultaneously communicating devices per spread factor per channel. That 1600 factor means their base station can handle massive numbers of clients compared to cellular. http://www.scribd.com/doc/273814075/On-Ramp-Wireless-White-P... . That paper is certainly biased in their favor, but the tech is real and they have serious d…

Hm, 1600 sounds like a lot. But depending on the applications it sounds like it might not be that much if it's 1600 over three square miles.

Re: How New Long-Range Radios Will Change the Internet of Things

#59

Post by bertm »

LoRa is a really cool technology. We are incorporating it into our networking stack/ hardware module. From field testing, we've seen about 4-6 miles line of sight, and about a mile through an urban environment (parking garage, apartment building, etc). Plus the bare radio chips are less than $10 bucks.

Re: How New Long-Range Radios Will Change the Internet of Things

#60

Post by slewis »

0898 wrote: post #50
blhack wrote: post #13

This is un. fucking. real. I work in the IoT space (specifically on health devices), and something like this would be absolutely a GOD SEND for the things that we're doing. The current "hottness" in our space is bluetooth low energy (BLE). This is super low power (or, rather: chips that are really good at going to deep sleep, and then coming online very quickly to burst some data out), but the range on BLE isn't grea…

Just curious – why is range limited by a protocol? Why couldn't you send Bluetooth over hundreds of miles with a big enough antenna, for example?

You can amplify a signal and send it far. But due to FCC regulation in the 900MHz band for example you can only instantaneously transmit at 30W.

Another way to make a signal go further is to transmit at a lower data rate (thus spreading your signal out over time so that in effect you have more power in the signal). The FCC limits "dwell time" in a single channel to .4s in the 900MHz band.

Yet another way to increase range is to increase your receive sensitivity. Lora's Chirp Spread Spectrum coding actually allows signals to be received below the noise floor. You can liken this to decrypting data: to an observer the signal looks like noise, but if you know how to look within the noise you can pull the actual coded information out.

All of these LPWAN technologies use different forms of coding and signal spreading over time to get long range. Note how spreading your signal over time means your throughput goes down.

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