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Researchers Make Low-Power Wi-Fi Breakthrough (networkworld.com)

Posted by timothy on from the bouncy-bouncy dept.

alphadogg writes: The biggest downside of Wi-Fi for most users might be that it can really drain your smartphone or tablet battery, but a research team at the University of Washington has come up with a way to make using the nearly ubiquitous wireless technology in a less taxing way. They have demonstrated a technique for using 10,000 times less power than typical Wi-Fi (well, at up to 11Mbps anyway) and next month will present a paper titled "Passive Wi-Fi: Bringing Low Power to Wi-Fi Transmissions" at the USENIX Symposium on Networked Systems Design in Santa Clara. The main trick involves decoupling digital and analog components of a typical Wi-Fi router.

99 comments

  1. I'd prefer long range by RogueWarrior65 · · Score: 2

    Blazing speed and low power are less important to me than long range. And these router manufacturers are getting rather annoying with their "specs." Oh, it covers 14,000 square feet. That's a square less than 120 feet on a side. So what? That's what you get for 600 mW of output power?

    1. Re:I'd prefer long range by Pseudonymous+Powers · · Score: 5, Funny

      These router manufacturers are getting rather annoying with their "specs." Oh, it covers 14,000 square feet. That's a square less than 120 feet on a side.

      Never mind the rest of the specs. The real story here is, how'd they get their radio antenna to cover a square instead of a circle?

    2. Re:I'd prefer long range by Anonymous Coward · · Score: 0

      Blazing speed and low power are less important to me than long range.

      That's what she said.

    3. Re:I'd prefer long range by swb · · Score: 3, Insightful

      Besides the power requirements, the problem with long range is that there's limited spectrum allocation so your extended range ends up being someone else's interference and you both end up with reduced throughput due to competition for the spectrum.

      Then there's the security implication of excess range -- your network being reachable where you might not want it reachable. Sure, you're relying on security to prevent malicious access, but that works better when there's no access at all.

      The question I would have is if they only have the data rate is only 11 Mbps, it seems to cover a lot of the use cases already covered by Bluetooth.

    4. Re:I'd prefer long range by Eloking · · Score: 4, Insightful

      Blazing speed and low power are less important to me than long range. And these router manufacturers are getting rather annoying with their "specs." Oh, it covers 14,000 square feet. That's a square less than 120 feet on a side. So what? That's what you get for 600 mW of output power?

      Why not both?

      I didn't read TFA, but if that passive antenna is slower and have less range, it won't replace the wifi of our smartphone anytime soon.

      But I don't think it'll be impossible to implement that passive technology to actual antenna. So if you're not using a lot of data (sleep mode) and a good wifi signal is available, the phone could turn off the "active" antenna and activate the "passive" low power one.

      Just an idea.

      --
      Elok
    5. Re:I'd prefer long range by Bengie · · Score: 1

      Sounds useful for something like Bluetooth

    6. Re:I'd prefer long range by avandesande · · Score: 1

      Or perhaps (please don't shoot me for this) IOT devices.

      --
      love is just extroverted narcissism
    7. Re:I'd prefer long range by Jason+Levine · · Score: 5, Funny

      I'd be highly concerned if a router only covered a two dimensional area. You definitely want to pay extra for the router that can cover a cube or a sphere.

      --
      My sci-fi novel, Ghost Thief, is now available from Amazon.com.
    8. Re:I'd prefer long range by squiggleslash · · Score: 1

      Meh, I'd prefer shorter range, but some way to create multiple access points in a user friendly way to make the range work the way you want. Needless to say, those APs should be cheap.

      I want to elminate blackspots in my own home. What I don't want to do is give the neighbors free internet access.

      --
      You are not alone. This is not normal. None of this is normal.
    9. Re:I'd prefer long range by hawk · · Score: 1

      Ehh.

      For most settings, a hemisphere is fine . . . basements are rare around here . . .

      hawk

    10. Re:I'd prefer long range by Grishnakh · · Score: 1

      You don't have to give your neighbors free internet access. Haven't you heard of WPA2? It's not hard to use.

      The problem with multiple APs is that then you have to figure out a way to wire them all up to your router. Depending on how your house is laid out, that may not be that easy to do.

      You do have a good point, however, about setting up multiple APs being a pain in the ass; generally, you need enterprise-level equipment, RADIUS authentication, etc. to do that.

    11. Re:I'd prefer long range by Anonymous Coward · · Score: 0

      Never mind the rest of the specs. The real story here is, how'd they get their radio antenna to cover a square instead of a circle?

      More creative math I would guess. Once you start using math to lie, anything's possible!

    12. Re:I'd prefer long range by Phreakiture · · Score: 1

      Yeah, I hear you.

      As a radio hobbyist, one of the things that really irritates me is all of the consumer-grade two-way radios that make increasingly bold claims about the distance you supposedly can reach with them. This is an extension of that same behaviour. Any claim, at any power level, of an ability to reach a particular distance, without defining the terrain, is speculation at best, and marketing bullshit more oft than not.

      --
      www.wavefront-av.com
    13. Re:I'd prefer long range by enwewn · · Score: 1

      They always use free space (perfect space) to make these claims. They are math not real world.

    14. Re:I'd prefer long range by Anonymous Coward · · Score: 0

      What I don't want to do is give the neighbors free internet access.

      WTF? Turn in your geek card on your way out.

    15. Re:I'd prefer long range by MobileTatsu-NJG · · Score: 1

      It's digital, duh!

      --

      "I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)

    16. Re:I'd prefer long range by wwalker · · Score: 1

      Same way you drill a square hole!

    17. Re:I'd prefer long range by Eloking · · Score: 1

      Sounds useful for something like Bluetooth

      As I said, I didn't read TFA but, for what little I know, that passive technology need a powerful source. So, basically, the host use a lot more power so the devise use less.

      And for most Bluetooth application in my head, both use batteries.

      --
      Elok
    18. Re:I'd prefer long range by edtice1559 · · Score: 1

      Bluetooth is the first thing I thought about when I read this. Bluetooth actually has three modes. Low/Med/High just for this reason.

    19. Re:I'd prefer long range by rsborg · · Score: 1

      Meh, I'd prefer shorter range, but some way to create multiple access points in a user friendly way to make the range work the way you want. Needless to say, those APs should be cheap.

      I want to elminate blackspots in my own home. What I don't want to do is give the neighbors free internet access.

      Neighbors are one thing - how about interlopers in cars parked in front of your house? My house has a small curb setback - so we had to rip out our xfinitywifi router because it was delivering service (outside our firewall) to strangers - which I really don't mind - but they stayed parked in front of my house with their engines running. Annoying to say the least.

      --
      Make sure everyone's vote counts: Verified Voting
    20. Re:I'd prefer long range by Solandri · · Score: 1

      The limited range is what allows these open frequencies to remain open. Because the power is limited, your neighbor's wifi isn't able to overwhelm your wifi, and the two can reasonably co-exist.

      If you want greater range, you need to move to a directional antenna. Currently, this means something like a Yagi. But there's hope on the horizon. Newer wifi chipsets are using multiple receivers (the math for a receiver is the same as for a transmitter, so they are interchangeable). Right now it's only used to separate out multipath signals to increase bandwidth. But in the future, this should transition to full phased array antennas.

      By mathematically "pointing" the antenna directly at the antenna you're communicating with, you're able to reject noise coming from other directions and thus increase range, without increasing power. Likewise, because other people's antennas are picking up only directional signals, your transmissions will not interfere with them unless your signal path happens to be parallel and in-line with their signal path. So Shannon's Law on the limits of information bandwidth no longer apply either (well, it still applies, but your noise floor is now directional so multiple people can use the same channel without creating noise for each other, essentially acting as if each has their own independent channel even though they're broadcasting at the same frequency.)

    21. Re:I'd prefer long range by RicktheBrick · · Score: 1

      I would think that someone could design a faucet that could generate enough power just by turning it on or off so that it could report this to a computer. I would want the same for my gas stove. I would than put flow sensor in the water and gas lines so that if there is flow without something being turn on the computer would know there is a problem and attempt to do something about it. A computer should know about any flow in my house(gas, electricity, and water) and know the exact reason for that flow. The computer should know when every window and door is open. It should know not to heat or air condition if there is a window or door open. It should tell me if I want heat or air conditioning, I should shut the window or door. This should include interior doors too. The computer should be smart enough so that if it is cool enough outside that I should have fans to draw that air into the house. I have a force air heater so it should not be much of a problem to use its fan to draw outside air into the house. I would hope that my refrigerator would know when the outside air is cold enough to cool my food and have a vent so it could get the outside air instead of using a compressor. I do not see why google or microsoft have not designed a system that would save more money than it cost. The computer would tell me when I could take a shower or wash my dishes or clothes so it could heat my water only when needed. I can see plenty of ways to save energy.

    22. Re:I'd prefer long range by thegarbz · · Score: 1

      Range is limited by the FCC requirements for the spectrum allocated, not so much the technology which is already doing borderline black magic to achieve what is does given the form factor limitations.

    23. Re:I'd prefer long range by Carnildo · · Score: 1

      Same way you drill a square hole!

      Like this? https://www.youtube.com/watch?...

      --
      "They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
    24. Re:I'd prefer long range by Anonymous Coward · · Score: 0

      http://i.imgur.com/SW4aP3e.gif

    25. Re:I'd prefer long range by Anonymous Coward · · Score: 0

      I thought all you had to do was give them the same network name and WPA2 key, and make sure the APs are on the same subnet and everything would work more or less seamlessly.

    26. Re:I'd prefer long range by antdude · · Score: 1

      Even if it is slow like dial-up modem connections? [grin]

      --
      Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
    27. Re:I'd prefer long range by Big+Hairy+Ian · · Score: 1

      Never mind the rest of the specs. The real story here is, how'd they get their radio antenna to cover a square instead of a circle?

      They must have used a Squarial https://en.wikipedia.org/wiki/...

      --

      Build a Man a Fire, and He'll Be Warm for a Day. Set a Man on Fire, and He'll Be Warm for the Rest of His Life.

    28. Re:I'd prefer long range by Anonymous Coward · · Score: 0

      Actually, I feel that a good number of them actually manage to make L's and Donuts and Lopsided Torus' that just manage to never cover where i want to sit.

    29. Re:I'd prefer long range by Phreakiture · · Score: 1

      Exactly. Let me offer some anecdotal examples.

      My real world experience is that in my relatively flat residential neighbourhood, 400m is about the limit between handheld UHF radios (tried on both 450ish and 915ish MHz frequencies), ranging from 500mW to 7W. VHF (around 140-155 MHz) goes a little further under those circumstances (there are lots of trees in my neighbourhood, and trees have a larger negative impact on UHF than VHF).

      At the same time, put one end on top of a hill, mountain, tower, building, or other tall thing, and the range, even at the same power level, becomes what they say on the package and often then some.

      (Before someone asks, because radio nazis are everywhere, yes, all my radios are legal. I am a licensed ham, but also use MURS and FRS as well as some proprietary spread-spectrum radios on 915 MHz)

      --
      www.wavefront-av.com
    30. Re:I'd prefer long range by Shirley+Marquez · · Score: 1

      With the antennas of a router (with external antennas) in the usual configuration (all pointing up), the radiation pattern of a router will be more like a torus (shaped like a doughnut). It will radiate equally well in all directions on the router's plane, with reduced signal off-axis up or down. There will be very little signal directly above or below the router. The weak radiation up and down is one reason that multistory houses often need more than one access point. If the router has more than one antenna, people sometimes change the orientation of some of them to make the coverage area more like a sphere; that works reasonably well with 802.11b and g routers because the extra antennas are used for diversity reception, but less well for MIMO systems (801.11n and ac) because the multiple antennas are used simultaneously to increase the data rate.

      In the real world, the coverage of a router antenna will not be a perfect torus. The presence of the body of the router, the other antennas if the router has more than one, and other nearby metallic objects will all change the antenna pattern.

    31. Re:I'd prefer long range by Shirley+Marquez · · Score: 1

      More range though. The most common variety of Bluetooth only has a 10 meter range.

    32. Re:I'd prefer long range by eric_harris_76 · · Score: 1

      And quadcopters?

      --
      There's no time like the present. Well, the past used to be.
  2. Imagine..A cell phone with over 50% more battery by evolutionary · · Score: 1

    So many people use Wi-Fi on their phones for Internet and VoIP phone calls (plus Whatsapp..etc). Would be cool not to have to worry about my phone battery going dead within a few hours after using the Wi-fi for Internet.

    --
    "Imagination is more important than knowledge" - Einstein
  3. Well, no. by msauve · · Score: 1

    Wi-Fi is a registered trademark which indicates certified compliance and interoperability with an industry trade group's requirements. This ain't that.

    --
    "National Security is the chief cause of national insecurity." - Celine's First Law
    1. Re:Well, no. by MightyYar · · Score: 1

      And never xerox a paper or take an aspirin. Don't cool your food with dry ice or store it in a thermos. Don't ride an escalator. Put down your flip phone.

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    2. Re:Well, no. by msauve · · Score: 1

      I make photocopies on occasion. Aspirin, dry ice, thermos, escalator and flip phone are not trademarks in the US.

      --
      "National Security is the chief cause of national insecurity." - Celine's First Law
    3. Re:Well, no. by MightyYar · · Score: 1

      Not anymore, but they all were.

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    4. Re:Well, no. by msauve · · Score: 1

      So your point is, what? Wi-Fi is still a trademark.

      Someone pitching a technical academic paper who doesn't know the correct terminology for that technology is demonstrating ignorance, not knowledge.

      --
      "National Security is the chief cause of national insecurity." - Celine's First Law
    5. Re:Well, no. by cellocgw · · Score: 1

      Yeah, well,... I used the term "wi-fi" long before some genius trademarked it. Guess all of us techies never thought of doing that (trademarking an obvious adapted slang term).

      --
      https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
    6. Re:Well, no. by MightyYar · · Score: 1

      It's not an academic, it's an industry rag pointing to some interesting research. The article itself gives almost no useful information other than to show that it exists. Diluting a trademark is hardly a cardinal sin in this case. I'm not even sure what the generic term is that they should use, but I am sure that it would be liable to confuse their target demographic.

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    7. Re:Well, no. by MightyYar · · Score: 1

      Ah, I take it back. Didn't RTFA (the other one). I agree the academics should probably say "WLAN" or something. Whatever the standard is.

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    8. Re:Well, no. by msauve · · Score: 1

      You quite obviously haven't even looked at the paper,which was conveniently linked in the summary. Buh-bye, I see no point in further discussion with someone so deliberately ignorant.

      --
      "National Security is the chief cause of national insecurity." - Celine's First Law
    9. Re:Well, no. by MightyYar · · Score: 1

      Yeah, I admitted as much - though sadly not before you responded.

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    10. Re:Well, no. by skids · · Score: 1

      802.11b in this case. Considering the phase this research is at it is not surprising compliance tests have not been engaged.

      Assuming they aren't polluting outside their band, given the range they demonstrated they've got something viable here -- WiFi is headed towards a microcell architecture (consumer gear has yet to realize it, but the enterprise is already moving that way) and APs could easily embed side-stream transmitters, and maybe even wedge it into the channel plan in one of the 802.14.5 troughs (or in a stray channel up in 5GHz.)

      Whether they'll be able to get this to work on 11n/11a/11ac and manage to secure it compatibly with WPA2-enterprise are interesting questions. Then again IoT manufacturers have shown they are going to ignore the latter point entirely until such a time as they get sued enough that it starts to hurt their bottom line. That probably won't happen until the sector has raced to the bottom and has almost no profit margin. The lawyers will be the only ones happy after the dust settles.

      --
      Someone had to do it.
  4. Useless! Amplitude trumps all by Anonymous Coward · · Score: 1

    SNR level is going to suck with other higher powered 2.4Ghz being that it's already unlicensed spectrum.

  5. Re:Imagine..A cell phone with over 50% more batter by Ol+Olsoc · · Score: 1

    So many people use Wi-Fi on their phones for Internet and VoIP phone calls (plus Whatsapp..etc). Would be cool not to have to worry about my phone battery going dead within a few hours after using the Wi-fi for Internet.

    Even cooler if the wifi signal could charge my phone.

    --
    The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
  6. Holy shit! Free energy! by Orgasmatron · · Score: 1

    A WiFi system that generates 9.999 watts of free energy per milliwatt of transmit power is going to rewrite ALL of the physics books!

    Oh, wait, never mind. The author just meant that it uses one ten-thousandth as much power as standard methods, but was apparently too dumb to write it properly.

    --
    See that "Preview" button?
  7. USINEX by Noah+Haders · · Score: 1

    > next month will present a paper titled "Passive Wi-Fi: Bringing Low Power to Wi-Fi Transmissions" at the USENIX Symposium on Networked Systems Design in Santa Clara

    lol looks like UNISEX.

    1. Re:USINEX by wonkey_monkey · · Score: 1

      You need sex?

      --
      systemd is Roko's Basilisk.
    2. Re:USINEX by Anonymous Coward · · Score: 0

      If you are offering please first publish a photo.

  8. Re:yuo F41l It... by U2xhc2hkb3QgU3Vja3M · · Score: 0

    We keep dismissing these posts as trolls because of the goat.cx link, but what about the text itself? Are terrorists using Slashdot to communicate via secret messages?

  9. Re:Imagine..A cell phone with over 50% more batter by Shatrat · · Score: 1

    I think it would be pretty warm actually if you were pushing that much 2.4ghz into the room...

    --
    09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
  10. Re:yuo F41l It... by Anonymous Coward · · Score: 0

    Why is that comment a troll? It's off-topic at best.

  11. They "cheat" but it's still very useful by davidwr · · Score: 5, Informative

    It's not that it takes orders of magnitude less power, it's that they move the power-consuming-part to a device that isn't relying on a battery.

    Here's a comparison:

    Back in my grandfather's day, two kids who live on adjacent farms might use flashlights to "talk" to each other at night using Morse Code over distances of several hundred meters. But the flashlight batteries only had so much juice. But what if, instead of using flashlights, they used lenses and mirrors so they light source was a lamp that was plugged into the electrical outlet? They could talk all night and not use up any batteries at all.

    Well, that's the gist of these devices. The "low power battery-operated devices" still need batteries to do the equivalent of "manipulating the lenses and mirrors" and operating an RF receiver, as well as whatever other task they are supposed to be doing (say, monitoring for pollution, or whatever).

    They key is that they don't need to waste energy operating an RF transmitter - that work is done by a nearby device that has a reliable energy source.

    That, and several "low power" devices can "share" the same transmitter.

    Something not noted in the summary: Depending on the scenario, this may result in a net increase in power consumption if the "shared transmitter" is in a naive, "always on" mode compared to a conventional system where the transmitter(s) would only be on when needed. I'm not saying you can't design such a system that isn't "naive," just that if you do, your total power usage may be higher than a conventional system. But since you are "plugged in" and not on battery, it the "cost" may be negligible.

    Bottom line: It's a neat and useful trick and if "mains power" is "many times cheaper than battery power" for your application, this is a big win. On the other hand, if "overall power used" is the controlling factor, it's not such a big win and if you aren't careful, it could be a big loss.

    --
    Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
    1. Re:They "cheat" but it's still very useful by Mirar · · Score: 2

      (That needs to be modded up.)

      I find it very interesting. It basically means I can have a wifi device powered by a CR2032 battery for years;
      something a BLE device can do, but a z-wave device needs a CR123 battery.

      Wifi is a much more complicated protocol, but I think the point is that it works, as opposed to z-wave (xor checksum? really?) or BLE (good standard, but noone can implement it so it works).

    2. Re:They "cheat" but it's still very useful by Anonymous Coward · · Score: 0

      How does this differ from having any other wi-fi router in your home? Are those not "always on"? In any case, the wattage of one of those is in single digits - a pittance compared to anything else people have in their homes. The huge difference for a consumer would be enabling very long battery life in simple wireless appliances and peripherals (from wireless keyboards to home security systems), possibly longer than the useful lifetime of the device so the battery life would go from being a concern to not being one at all. It's less important for phones that do all kinds of processing and have power-hungry screens.

  12. Re:Imagine..A cell phone with over 50% more batter by Jason+Levine · · Score: 1

    Heat your room during the winter AND charge your devices at the same time!

    (Of course, during the summer this won't be very pleasant.)

    --
    My sci-fi novel, Ghost Thief, is now available from Amazon.com.
  13. Re:Holy shit! Free energy! by Anonymous Coward · · Score: 0

    >The author just meant that it uses one ten-thousandth as much power as standard methods,
    Or -40 dB relative to other methods (when talking about RF Power, better to use decibel representation)

  14. Just done decouple the heisenberg compensators! by Tighe_L · · Score: 1

    Or we could unleash a holograph Moriarty come to life! http://memory-alpha.wikia.com/...

    1. Re:Just done decouple the heisenberg compensators! by Tighe_L · · Score: 1

      I meant "Just don't decouple the heisenberg compensators!" I ruined my own bad joke

  15. Re:Holy shit! Free energy! by wonkey_monkey · · Score: 1

    I don't get what's problematic with anything that's been written.

    --
    systemd is Roko's Basilisk.
  16. 1000x better than blue tooth LE by goombah99 · · Score: 3, Interesting

    from the article "This translates to 10000x lower power than existing Wi-Fi chipsets and 1000x lower power than Bluetooth LE and ZigBee."

    The system works by remodulating the poweful carrier from a transmitter to shift it's frequency. Thus it doesn't need much power itself, it is just reflecting the power from a powerful source. The set the powerful source frequency just outside wifi channel frequncy and the reflected modulated signal is shiften inband. this lets an existing wi-fi receiver pick up the signal. Thus it works with conventional wiFi systems without them having to be aware they are communicating with a low power device. I believe it will require the addition of the high power transmitter of the carrier that is being passively reflected.

    --
    Some drink at the fountain of knowledge. Others just gargle.
    1. Re:1000x better than blue tooth LE by thegarbz · · Score: 1

      from the article "This translates to 10000x lower power than existing Wi-Fi chipsets and 1000x lower power than Bluetooth LE and ZigBee."

      That may be true for the actual transmission, but I wonder if it will equate to a real world difference in low-power long battery life systems where 802.15.4 is currently king. The problem being not so much the power used to transmit but the length of time needed on the protocol itself to do the work. Current low-power WiFi transmitters don't consume unreasonable amounts of power, but waking them from sleep, connecting, sending a packet and returning to sleep is something that can take several seconds. Comparatively Zigbee once the initial connection is made and the device is back asleep can wake, send data, and go back to sleep within 20mS. If you have an application that depends on sending a single small packet once per minute then on an 802.15.4 network you're limited by the shelf life of a typical lithium battery (10-20 years), on WiFi even the best transmitters currently get only weeks of battery life.

  17. Re:Imagine..A cell phone with over 50% more batter by Anonymous Coward · · Score: 0

    So many people use Wi-Fi on their phones for Internet and VoIP phone calls (plus Whatsapp..etc). Would be cool not to have to worry about my phone battery going dead within a few hours after using the Wi-fi for Internet.

    "Imagine...A cell phone with over 50% more battery"

    We don't have to imagine this. It pretty much happens every few generations of battery tech.

    (Yeah, I'm old enough to remember being charged per minute, managing offpeak rates, and having about an hour of talk time before the battery died. Needless to say, shit has improved considerably.)

  18. ugh! I meant 0.0001 times. by Anonymous Coward · · Score: 0

    I meant 0.0001 times.
    At least it is still grammatically correct.

  19. Mus electrodurans? by Applehu+Akbar · · Score: 2

    Let's hope for a wireless mouse that no longer needs batteries every time you pick it up.

    1. Re:Mus electrodurans? by locopuyo · · Score: 1

      There are plenty. I have a Logitech M510 at work and haven't replaced the batteries for 3 years. Logitech also has a wireless gaming mouse that will last 250 hours.

      --
      The Official Site of 1337 Pwnage
    2. Re:Mus electrodurans? by thegarbz · · Score: 1

      Huh? As someone who spends a lot of times playing games, and the rest of my time moving my mouse continuously (I move the mouse cursor around the screen while reading), I get between 6 months and a year out of my mouse. Off the shelf Microsoft mouse with a blue laser. My previous Logitech lasted just as long.

  20. microwave by Anonymous Coward · · Score: 0

    It is a great technology for communication inside a microwave oven.

  21. Clever - but not actually useful by Anonymous Coward · · Score: 0

    OK, so I did actually read TFA (I know that's against the rules, but that's just the kinda guy I am)

    The thing is that this still requires setting up another active, proprietary device in the building where you want it to work. So, the IoT devices are passive but the other component isn't.

    So what's the point? If you've got to deploy an active transmitter anyway, then that device can _itself_ be the bridge to wifi just like every other IoT solution that uses z-wave, Zigbee or other strange protocol X that may or may not be passive. And in (almost) all practical cases that is going to work much better, it's already implemented, standardised etc. etc.

    So, yeah, very clever and all, but not actually useful.

    If there was a pure passive solution then it would rock, but this ain't it.

    1. Re:Clever - but not actually useful by JoeMerchant · · Score: 1

      So, no better than any other wireless power scheme...

    2. Re:Clever - but not actually useful by skids · · Score: 1

      Lower power, possibly cheaper hardware, and can unify IoT device management with WiFi seem to be the primary potential benefits. How well it does and how long it can afford to stay proprietary and still be bothered with is a matter market economics will have to decide.

      --
      Someone had to do it.
  22. Re:Holy shit! Free energy! by MightyYar · · Score: 1

    "n times less than x" is very common speech. It means, as you say, one x divided by n. It is unambiguous, because the only other interpretation (x minus n times x) provides a value which - as you point out yourself - makes absolutely no sense at all. This is not a good example of someone being "dumb".

    --
    W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
  23. No such thing... by Nunya666 · · Score: 1

    ...as "10,000 times less."

    1. Re:No such thing... by Anonymous Coward · · Score: 0

      Yeah I guess not every CPU has the luxury of a division instruction.

      In all seriousness though... i guess there is such a thing as "times less" if taken literally rather than meaning fraction of... the only problem being that anything "more" than "1 times less" would be negative.

    2. Re:No such thing... by ScentCone · · Score: 1

      No such thing as "10,000 times less."

      Well, there is, but that's not how most people use it. That phrase only makes sense when you're saying something like (for proper context), "The old batteries were large, at 10cm wide. The newer batteries were smaller, at 5cm. But these latest batteries are more than twice as small, at only just over 1cm." But even that construction is awkward. It's a lot easier to say, "The newest batteries are less than a quarter the size of the originals." The "X time smaller" construct only makes sense when you're comparing the size to something that's already considered small compared to something else ... because it's the "er" that counts.

      --
      Don't disappoint your bird dog. Go to the range.
    3. Re:No such thing... by LinuxIsGarbage · · Score: 1

      But even that construction is awkward.

      Not as awkward as your use of quoting.

      The problem I think comes in when fractions or percentages below 1% try to be expressed.

      The newer batteries at 5cm are half as big. The newest batters are a fifth the size at 1cm. The bleeding edge batteries are 0.5% the size at 50 Micrometers.

    4. Re:No such thing... by ScentCone · · Score: 1

      Percentages and fractions (depending on what's trying to be visualized) are BOTH a better bet than "500 smaller than..." unless the entire point of the expression is to say "A is big, B is smaller by some amount, and C is five times smaller than that." Because in that context, A>B>C, it's the fact that C is even smaller than something else that was already small (compared to something else) that is the point of what's being said. But that's almost NEVER what the "500 smaller than" people are trying to say. They're almost always trying to say, "B is only 1/500th the size of A."

      --
      Don't disappoint your bird dog. Go to the range.
    5. Re:No such thing... by TeknoHog · · Score: 1

      In all seriousness though... i guess there is such a thing as "times less" if taken literally rather than meaning fraction of...

      Wow, imagine a world where words and phrases are taken literally. You could even say something like "one 10,000th of the power" to refer to the fraction, and actually be understood. But hey, language changes, let's just get over it and say jotain ihan vitun randomia, and let the reader/listener worry about the intended meaning.

      --
      Escher was the first MC and Giger invented the HR department.
    6. Re:No such thing... by Nunya666 · · Score: 1

      No, it never makes sense.

      It's just bad grammar. Just because "most people do it that way" is merely proof that most people are idiots. It does not justify doing something the wrong way.

      The fact that the same usage is seen in modern advertising does not help the situation. The people creating that advertising are probably coddled 20-somethings who were never told they were wrong because their feelings might get hurt.

  24. Grammar much? by Anonymous Coward · · Score: 0

    "...has come up with a way to make using ... in a less taxing way"

  25. Beam Forming by Anonymous Coward · · Score: 0

    Never mind the rest of the specs. The real story here is, how'd they get their radio antenna to cover a square instead of a circle?

    Beam forming antenna array. Also, magic.

  26. Re:yuo F41l It... by koreanbabykilla · · Score: 1

    I have seen a few discussions on here pondering the possibility it being a numbers station, been happening a little too long for it to be the current crop of "terrorists" I would think tho.

  27. Another way to do it: block analytics by edxwelch · · Score: 1

    Practically every mobile app has analytics of some sort. This provides no value whatsoever to the user and wastes power sending data to the server. There are some firewall apps that can do this.

  28. Re:Holy shit! Free energy! by FakeStreet123 · · Score: 1

    This is, however, a perfect exemple of someone being a pedant.

  29. Re:Holy shit! Free energy! by MightyYar · · Score: 1

    In all fairness, it's a good trait in a programmer :)

    --
    W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
  30. Username! by Anonymous Coward · · Score: 0

    What secret info are you communicating in your username!?

    1. Re: Username! by Anonymous Coward · · Score: 0

      It's "Slashdot Sucks" encoded in base64

    2. Re: Username! by U2xhc2hkb3QgU3Vja3M · · Score: 1

      You're the first one I've seen to finally decode it and write about it.

      It only took what, a few months?

  31. Re:Holy shit! Free energy! by Blaskowicz · · Score: 1

    That is called language. When the locution is used the other way around, it fails the literal interpration too. When you say something is "50 times more expensive", the intended meaning is that the price or cost is 50x that of the other item, and not 51x. Thus "times more" is a straight multiplication not a multiplication and addition. "Times less" is the reciprocal, thus it is a division not a multiplication followed by a negative addition*.

    * Tought experiment : k is the factor. Literal "times more" means A = B * (k+1).
    A new interpretation of "times less" allowing the substitution of multiplication by division is A = B * 1/(k+1), so "10000 times less" would mean "divided by 10001"?

  32. Re:Holy shit! Free energy! by Anonymous Coward · · Score: 0

    This is why educated folk would say "50 times *as* expensive."

  33. Re:I'd prefer long range- NOT by whit3 · · Score: 1

    Blazing speed and low power are less important to me than long range.

    Long range is important, because in a dorm, tall office building, apartment, or crowded library it backs up my traffic behind all the competing signals in the region. I'll get my faster service from a wired connection (about half a millimeter range of the little plastic connector body). For a host of minor tasks, like TV remote control, thermostat setting, smoke alarm, and zombie attack warning (it sounds better than home intrusion alarm), the battery life is of greater importance. It looks like this scheme allows me to put a single beacon in some central location in the house, and feed it a half watt. Then, all the minor slowpoke appliances I want can communicate to my existing WiFi infrastructure without breaking a milliwatt.

    It's claimed this adds only ten microwatts power drain, and delivers WiFi connectivity.

    Ten microwatts is gonna drain two AA batteries in two decades. It's short range, so my neighbors aren't a problem for me, nor I for them. I think I'll like it. Cordless game controllers... decade of battery life...

  34. Really-Low Power Medium-speed is cool too! by billstewart · · Score: 1

    Sure, there are times that longer range is what you need, but there are a lot of applications for which Really Low Power is a real enabler, and 11 Mbps is plenty (while Bluetooth/BLE/Zigbee speeds may not be), plus being able to use one software stack instead of having to keep a Bluetooth one and a Wifi one or needing some badly designed hopelessly insecure IoT gateway box is a big win. 1kbps is enough to drive your lightbulbs, but if your refrigerator needs a software update or whatever, the higher speeds are useful.

    I'm still using 3Mbps DSL at home (don't watch enough TV online to make 6Mbps useful), so 11 Mbps is fine, though I've upgraded from 802.11b to .11n for higher reliability (and I'd use 5GHz if my router could do both radio types at once.)

    --

    Bill Stewart
    New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
  35. 30-100 feet is enough for smartphone wifi by billstewart · · Score: 1

    Occasionally it might be nice to have longer range, but 30-foot through-wall and 100-foot free-space is usually enough for most wifi environments I'm in, and having a phone wifi that didn't burn battery so fast would be extremely useful, and would more than justify having to put a few extra wifi repeaters in my office space.

    --

    Bill Stewart
    New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks