Talk softly, but equip a large aerial
February 26, 2016 4:55 AM   Subscribe

The University of Washington has developed Passive Wi-Fi. A method of generating 802.11b transmissions using backscatter communication, while consuming 10000 times less power than existing Wi-Fi chipsets (and 1000 times less power than Bluetooth or Zigbee) Passive Wi-Fi transmissions can be decoded on any Wi-Fi device including routers, mobile phones and tablets.

More details are in the paper here.
posted by Just this guy, y'know (40 comments total) 23 users marked this as a favorite
 
This is awesome. Essentially, with this technology there's no reason to ever turn off wifi on a device, just put it into low-power mode. This could also be useful for small devices, like medical sensors or video game controllers.
posted by Mr.Encyclopedia at 5:05 AM on February 26, 2016 [3 favorites]


My Wi-Fi is often passive, but not in a good way...
posted by jim in austin at 5:12 AM on February 26, 2016 [1 favorite]


Before you get too excited, bear in mind that 802.11b is pretty antiquated tech to be putting in your laptop or smartphone- 802.11g, which does up to 54 Mbps vs 802.11b's 11 Mbps, has been the consumer standard for years, with 802.11n (up to 600 Mbps) overtaking 802.11g in recent years. Unless this technology can provide much better bitrates than what they've demonstrated, this is going to make a difference in other areas but probably not in your phone.
posted by Pope Guilty at 5:26 AM on February 26, 2016 [4 favorites]


This very cool, and most likely useless until they can get it to work on a better standard than 802.11b. Most home routers don't have dual antennas to run multiple standards.

It would be interesting to see if it'd be worth embedding a 802.11b transmitter in a XBOX or something for the extended battery life on controllers.
posted by mayonnaises at 5:28 AM on February 26, 2016 [1 favorite]


Expressing '1/x something' as 'x times less something' has always seemed not mathematically correct to me.
Other than that, this is cool.
posted by MtDewd at 5:30 AM on February 26, 2016 [4 favorites]


You have to watch out for passive-aggressive Wi-Fi. It uses less power, but is detectably annoyed whenever you ask it to download something.
posted by Strange Interlude at 5:30 AM on February 26, 2016 [42 favorites]


I think the usage is much more important than bit rate.

this is basically a step forward in internet of things. During next few years, a lot of devices can work with transmission rates less than 11 mbps.

also, today, power is the limiting factor .. so devices which use little power will become more important than devices allowing high bandwidth .... just like ARM processors over intel.

There are so many power consumption constraints in communication and transmission that anything that overcomes them is amazing news.
posted by TheLittlePrince at 5:33 AM on February 26, 2016 [7 favorites]


Pope Guilty - I don't see this as replacing current high bitrate wifi tech, but something more along the line of IoT, or putting your phone in low power mode but still getting push notifications at 11 Mbps.
posted by thecjm at 5:35 AM on February 26, 2016 [3 favorites]


You have to watch out for passive-aggressive Wi-Fi. It uses less power, but is detectably annoyed whenever you ask it to download something.

Oh, no, go ahead, use Wi-Fi Assist, I'm fine. You don't think I'm good enough for you, I know. I've always known. Here I am trying my best to pull music and videos and web pages for your out of the luminiferous aether, but apparently that's not just impressive enough for you.

I'm going to my mother's.
posted by leotrotsky at 5:35 AM on February 26, 2016 [20 favorites]


I look forward to never, ever being able to escape the internet.
posted by Happy Dave at 5:35 AM on February 26, 2016 [11 favorites]


this is basically a step forward in internet of things.

All the more reason to roll eyes at it.
posted by Pope Guilty at 5:38 AM on February 26, 2016 [10 favorites]


Don't think of this as a replacement for any existing wifi. The point here is that you can't currently use WiFi in passive sensors because it uses too much power, so you need to mess about building mesh networks or zigbee and putting zigbee hosts and then an interface to wifi.

What you can do with this is stick the passive wifi chip, a sensor, a tiny battery and a magnet and make sensor throwies.

Sensor throwies that can last for years and can report easily to anyone nearby.
You could equip a van with a wifi hotspot and a PC set to listen and drive around the city auto gathering data, or hook into the internet from existing public wifi.
posted by Just this guy, y'know at 5:42 AM on February 26, 2016 [7 favorites]


I've read the paper. It reads like a VC pitch, because that's what it is. The authors have started a company and need funding. Having a peer-reviewed paper will help baffle the VCs.

The paper will not pass peer review in its current format, but that's not a problem. It's not an impossible or stupid idea. I suspect things like this will become useful.

The basic idea is to use a powered base station to power remote transceivers with in-band power. This can work. It's wildly inefficient, but it can and does work.

It's a digital-age version of The Thing - a passively powered remote transmitter.

Nice work, good luck with the financing for the start-up! The patents should be a slam-dunk.

I just counted how many internet-connected devices there are within ten metres of me that have a microphone.

Eleven. And four of them have cameras.

If this idea makes it to market, switching them off won't be enough.

This future is getting very, very creepy.
posted by Combat Wombat at 5:52 AM on February 26, 2016 [26 favorites]


Heh, 802.11b, like people haven't been turning off 802.11b support as aggressively as possible in recent years because it's garbage and letting 802.11b clients on reduces performance for the 802.11g and 802.11n (and 802.11AC if you are doing AC in the 2.4 Ghz range- shudder).

So what this is liable to result in is even more congested wireless spectrums as we are going to need to put in parallel wireless networks for passive sensor wireless devices and a separate network for high speed wireless data transfers for high-end wireless clients.

A lot of that can be accomplished by in effect abandoning the 2.4 Ghz range to the lower-end devices and exclusively using 5Ghz channels for high-speed wireless which is good because the maximum number of usable channels in 2.4Ghz wireless is 3 and that rapidly results in a completely saturated spectrum due to so many APs residing in the same channel (witness just about any apartment complex in the world).

For large institutions that have thousands of APs this sort of parallel network is going to be a major pain in the ass to manage.
posted by vuron at 6:12 AM on February 26, 2016 [1 favorite]


I like scoffing at rubbish Internet of Things implementations as much as the next person - and there's plenty of scoffin' to be had - but living with a partner who has a blind spot when it comes to turning off lights means that smart bulbs, motion detectors, schedules and geofencing make both of us happier and less angsty / nagged.
posted by sektah at 6:19 AM on February 26, 2016 [3 favorites]


It's new tech. If it's legit, it's only a question of when they'll get faster bitrates, not if.

Rolling your eyes at the speed of a brand new low-power wireless protocol is like being around for the invention of TV and saying "well, I GUESS, but the REAL WORLD is in COLOR and 3D and has SMELLS, you guys, wake me when I should CARE"
posted by middleclasstool at 6:32 AM on February 26, 2016 [3 favorites]


re IoT etc. this reminds me of the tiny networking remotes in Vernor Vinge's _A Fire Upon The Deep_
posted by Heywood Mogroot III at 6:51 AM on February 26, 2016 [4 favorites]


Internet of things is coming whether we like it or not. Every thing is going to get more and more networked.

Kind of inevitable, actually.

That doesnt mean that all the hype is real. The internet of things would be nothing like what pundits envision it to be but it will be there.

I would bet that within 10 years, internet will carry more consumer device originated communication than human originated communication.
posted by TheLittlePrince at 7:05 AM on February 26, 2016 [1 favorite]


Internet of things is coming whether we like it or not. Every thing is going to get more and more networked.

hell yeah! truckloads of cheap, insecure crap rushed to market and purchased by a phalanx of unsuspecting rubes. our lives will be sooo enhanced!
posted by quonsar II: smock fishpants and the temple of foon at 7:28 AM on February 26, 2016 [8 favorites]


Now someone, please invent cheap Faraday cage wallpaper and windowpanes.
posted by mubba at 7:53 AM on February 26, 2016 [7 favorites]


This could be a big deal for process plants (chemical factories, refineries, etc) because they have large numbers of devices spread out over a large area that all need to talk to each other and/or a controller. There is already some wireless mesh networking with battery power going on, but the power issue limits their update rate, which limits what they can be used for so lower-power communications is a good thing to expand the use of that technology.
posted by ArgentCorvid at 8:02 AM on February 26, 2016 [1 favorite]


You have to watch out for passive-aggressive Wi-Fi.

Which is why I named my home Wi-Fi network Marvin.
posted by nubs at 8:05 AM on February 26, 2016 [2 favorites]


The speed doesn't matter, you can always use the back scatter connection to wake up a real wifi chipset as needed.
posted by Chuckles at 8:07 AM on February 26, 2016 [1 favorite]


Yeah, I'm imagining previously hydro-mechanical gages that can be upgraded to wirelessly report their readings without any expensive new infastructure, or communication between small-scale "swarm" robots that various Sci-fi authors have promised us.
posted by Mr.Encyclopedia at 8:32 AM on February 26, 2016 [1 favorite]


quonsar II: smock fishpants and the temple of foon: "Internet of things is coming whether we like it or not. Every thing is going to get more and more networked.

hell yeah! truckloads of cheap, insecure crap rushed to market and purchased by a phalanx of unsuspecting rubes. our lives will be sooo enhanced!
"

I find it sad when I see such responses. Also, note that this dismissive-ness is not an outlier, uncommon response. If you look at this thread, not including cautious "wait and watch", I count about 5 negative/scared/dismissive responses out of 23.

Its basically a fear of technology and change covered in a sneering, hipster-ish veneer. Its weird to see this in an "intellectual, grown up" community.

I bet someone was grunting something similar about fire being insecure and being used by unsuspecting rubes who will get their houses burnt down around them.
posted by TheLittlePrince at 8:36 AM on February 26, 2016 [3 favorites]


I think noting that lots of tech applications are not properly secured is not a fear of change. Or really technology - having a healthy awareness of what tech can do means you're aware of its shortfalls. Not everyone has to want "smart" everything. I'll be happy with an efficient fridge that keeps my food cool. I don't need it to connect to wifi or track when I'm running out of milk or try to offer me coupons.
posted by brilliantine at 8:45 AM on February 26, 2016 [3 favorites]


Sure, there are a lot of spooky panopticon questions to ask about IoT enabled devices, but power scavenging sensors have been of interest to the NDE (non-destructive evaluation) community for a very long time. Example: building a new bridge with power-harvesting sensors integrated into the structure to monitor for failures. Until now, this type of application has been held back by short battery life and/or the need to wire the sensors. This type of backscatter harvesting could enable these types of long-term NDE and sensing applications.
posted by Existential Dread at 8:53 AM on February 26, 2016 [2 favorites]


Its basically a fear of technology and change covered in a sneering, hipster-ish veneer.

no, it's basically a realistic prediction of what the reaction of unbridled consumerism will be, covered in a sneering, cranky old man-ish veneer.

did i seriously just get called a hipster?
posted by quonsar II: smock fishpants and the temple of foon at 9:16 AM on February 26, 2016 [2 favorites]


Username: Admin
Password: Test
posted by Artw at 9:19 AM on February 26, 2016 [6 favorites]


Its basically a fear of technology and change covered in a sneering, hipster-ish veneer. Its weird to see this in an "intellectual, grown up" community.

I wrote zigbee software for a distributed sensor network in grad school. Because this was for the Tallgrass Prairie, privacy wasn't an issue and security was never considered. And my team was on the forefront of the development lab, using a system level language developed for the purpose of network and embedded computing while the rest of the students were writing assembler. And it kinda worked, because while professors are terrible technical managers, the product only has to work well enough to publish a paper, and may then evaporate.

I'm happy for new technology. I look forward to buying a new phone with non-directional wireless charging, and my computers, routers, and storage systems all run Linux.

My beef, and that of many others, with IoT is how it's already delivering on the promise of a broken, insecure future that manufacturers deny liability for. We still have issues with wireless routers, where the concern for security is obvious. But who thinks to check if their lightbulb's have undergone a security audit? This isn't an issue of problems the industry will research and solve; we know how to solve it. This is an issue of industry attempting to run their engineering division like a slapdash grad school program.

Portraying us as anti-intellectual is dissembling. I'm sorry if this opinion is getting in the way of your grant proposal, startup, or state surveillance program.
posted by pwnguin at 9:22 AM on February 26, 2016 [10 favorites]


> It's a digital-age version of The Thing - a passively powered remote transmitter.

holy crap how did I not know that Theremin designed spy technology?
posted by You Can't Tip a Buick at 10:45 AM on February 26, 2016 [1 favorite]


Its basically a fear of technology and change covered in a sneering, hipster-ish veneer. Its weird to see this in an "intellectual, grown up" community.

Name one invention that has not, in some way, contributed to human misery.
posted by Faint of Butt at 10:46 AM on February 26, 2016 [1 favorite]


Forget the "Internet of Things", this breakthrough brings us closer to the 'totally sci-fi in this movie 49 years ago' Cerebrum Communicator. (Yes, that was Pat Harrington in what I will always consider his greatest role)
posted by oneswellfoop at 11:26 AM on February 26, 2016


Its basically a fear of technology and change covered in a sneering, hipster-ish veneer. Its weird to see this in an "intellectual, grown up" community.

There's absolutely nothing sneering or hipsterish about actually understanding and being wary of the risks of so much insecure and sometimes insecurable technology (looking right at 802.11b, here) and how it may be terribly misused by many different entities in many different ways.

We're already entered a world where something like cheap and fancy LED light bulb or a child's toy is more than capable of sniffing your banking details or intellectual property or even just your sex life because the damn thing has a tiny computer and network stack in it so you can make it change colors with your phone.

Not to mention your TV, your computer, your video game console, your phone, your watch, your car, your refrigerator...

And, yes, obviously, there are a lot of benefits, too, but the risks and negatives aren't simply erased by the positive attributes. The positive and negative impacts of any technology exist simultaneously.
posted by loquacious at 11:35 AM on February 26, 2016 [2 favorites]


The low bitrate isn't really an issue because this is intended for very low bandwidth applications. For high bandwidth applications, the digital processing on the back end consumes more power than the wifi so there wouldn't be a power advantage to passive wifi. It's applications where the battery powered digital processing is minimal that passive wifi makes sense in order to extend battery life to months and years. Those applications by necessity must be low bandwidth to reduce digital power.
posted by JackFlash at 12:37 PM on February 26, 2016 [2 favorites]


Name one invention that has not, in some way, contributed to human misery.

The smallpox vaccine. Water purification. The polio vaccine. Sewer systems. Glasses. Hi-fi record players.

Perhaps the clarinet, though your mileage may vary.
posted by thecaddy at 2:00 PM on February 26, 2016 [4 favorites]


Vaccines, pure water and sewerage systems help promote overpopulation, which brings much misery now and -exponentially -in the times to come.

Glasses let old people read, slowing down the rate of young people advancing in the literate and numerate professions, also academe, thus putting much inertia in the progress of ideas

Clarinets - any musical instrument in the hands of the enthusiastic and untalented is a major cause of human misery, right there.

As for passive wi-fi - Maxwell and Shannon say you cannot get something for nothing, power is king, and power falls away according to the inverse square law. There will be a very small class of uses where this is an enabler, because multiple solutions already exist for most of the problems it addresses, even if it all works out to the limits of what physics and the state of the art in engineering allow.
posted by Devonian at 2:22 PM on February 26, 2016 [2 favorites]


there is a difference between being cautious about new tech and being outright negative about it.

If you go through some of comments above, there is a hostility and a denial. There are comments which are cautious but there is a big proportion of negative/dismissive comments(not just in this thread, btw). The hostility could be because of valid concerns about how manufacturers, powers-that-be and The Man use any given tech.

Usually, people are unable to nuance between a tech and how people use it e.g. fire. And, sometimes, tech is actually very dangerous, eg. technology to kill ppl. But, I think, its important for us to be able to distinguish between the multiple human choices available in using a tech. Because without that distinction, there is not a lot of difference between us and ppl who use fear of unknown to guide their actions.

/derail
posted by TheLittlePrince at 4:27 PM on February 26, 2016 [1 favorite]


Its basically a fear of technology and change covered in a sneering, hipster-ish veneer.

No.
posted by bongo_x at 9:11 PM on February 26, 2016


I have no interest in communicating with my lightbulbs or my fridge, but I am really excited for this to get implemented in small research-oriented sensor packages.

Stuff like this mixed with tiny, low-power traffic sensors would make it possible to collect data like never before to verify the efficacy of all kinds of traffic calming solutions.

Combat Wombat, thanks for the link to The Thing! That is amazing and wonderful and makes me want an excuse to try and replicate it, though my fabrication skills probably aren't up to the task.
posted by sibilatorix at 10:29 PM on February 26, 2016 [1 favorite]


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