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Wi-Fi signals enable gesture recognition throughout entire home

washington.edu

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Re: Wi-Fi signals enable gesture recognition throughout entire home

#41

Post by nahname »

deserted wrote: post #12
networked wrote: post #4

>A standard Wi-Fi router could be adapted to function as a receiver. The article and the embedded video do not make it entirely clear but if this technology could be deployed in existing Wi-Fi routers with relative ease [1] then it could have far-going implications for both privacy and the physical security of anywhere where there's Wi-Fi. Once it's easy enough to deploy on a hacked device that a hired script kiddie…

From the paper [1] The WiSee proof-of-concept is implemented in GNURadio using the USRP-N210 hardware. Each USRP is equipped with a XCVR2450 daughterboard, and communicates on a 10 MHz channel at 5 GHz. Since USRPN210 boards cannot support multiple daughterboards, we built a MIMO receiver by combining multiple USRP-N210s using an external clock. In our evaluation, we use MIMO receivers that have up to five antennas. W…

Honest question, how can you have a 10MHz channel at 5GHz?

Re: Wi-Fi signals enable gesture recognition throughout entire home

#44

Post by gipsies »

deserted wrote: post #12
networked wrote: post #4

>A standard Wi-Fi router could be adapted to function as a receiver. The article and the embedded video do not make it entirely clear but if this technology could be deployed in existing Wi-Fi routers with relative ease [1] then it could have far-going implications for both privacy and the physical security of anywhere where there's Wi-Fi. Once it's easy enough to deploy on a hacked device that a hired script kiddie…

From the paper [1] The WiSee proof-of-concept is implemented in GNURadio using the USRP-N210 hardware. Each USRP is equipped with a XCVR2450 daughterboard, and communicates on a 10 MHz channel at 5 GHz. Since USRPN210 boards cannot support multiple daughterboards, we built a MIMO receiver by combining multiple USRP-N210s using an external clock. In our evaluation, we use MIMO receivers that have up to five antennas. W…

Even with enough MIMO 802.11n devices it's still practically impossible. They essentially need access to the raw signals to do all their calculations, but this isn't provided by drivers/firmware/devices.

If you're really lucky you have a device with open source firmware [1]. However even that firmware can only interface with the PHY layer by writing to registers to change the configuration of the device. Essentially the modulation of the signals is done in hardware, and you only control MAC aspects of it (things like disabling carrier sense is possible, changing backoff behavior, inter-frame wait timings, etc). But you can't access the real signal, it's a hardware limitation, so this not possible using existing devices.

[1] https://github.com/qca/open-ath9k-htc-firmware

Re: Wi-Fi signals enable gesture recognition throughout entire home

#45

Post by dangrossman »

nahname wrote: post #41
deserted wrote: post #12

Earlier quoted context omitted.

From the paper [1] The WiSee proof-of-concept is implemented in GNURadio using the USRP-N210 hardware. Each USRP is equipped with a XCVR2450 daughterboard, and communicates on a 10 MHz channel at 5 GHz. Since USRPN210 boards cannot support multiple daughterboards, we built a MIMO receiver by combining multiple USRP-N210s using an external clock. In our evaluation, we use MIMO receivers that have up to five antennas. W…

Honest question, how can you have a 10MHz channel at 5GHz?

"5GHz" really means 4.915GHz-5.825GHz, the frequencies in which 802.11n is allowed to operate. You could split that up into many 10MHz wide "channels" of non-overlapping frequencies.

Re: Wi-Fi signals enable gesture recognition throughout entire home

#46

Post by dm2 »

moron4hire wrote: post #32
TeMPOraL wrote: post #28

Earlier quoted context omitted.

It is already here if you care to spend some money on it.

I should have said "Home automation for the masses." I know, I worked at a startup in the space. The people who are capable of spending the money will spend the extra necessary to get someone to install it for them. The people who would install it themselves can't afford even the basic systems, as you need quite a few devices before the things get useful. The most profitable use we ever found for it was to provide li…

For under $1,000 you can easily build a significant home automation system.

http://www.amazon.com/b?ie=UTF8&node=2315509011

Re: Wi-Fi signals enable gesture recognition throughout entire home

#48

Post by ChuckMcM »

Ok DD-WRT folks, get to it :-) More seriously though, this is a pretty cool thing, using your motion which is blocking wireless signals to detect motion. In hindsight its kind of obvious since people are 'giant waterbags of attenuation' as my RF buddy calls them. This also means you can probably add something of a burglar alarm/motion sensor system to these things, and if you were careful you might be able to see the movement of people inside a house by looking at the WiFi signal leaving the house. Certainly if you're carrying around and active phone/tablet that would be trivial to do from outside (and by trivial I mean you would have lots of signal to work with and the math would be straight-forward, not that it would be simple)

Re: Wi-Fi signals enable gesture recognition throughout entire home

#50

Post by [deleted] »

Someone wrote: post #33
hammock wrote: post #31

Earlier quoted context omitted.

Your pet turns the shower on? That sounds like a real problem

I think he refers to having a system that, using this approach, turns on his shower when he enters it. If this cannot distinguish humans from cats, it would turn on the shower when a cat entered it. I think that's a bad example. The typical cat would soon learn not to enter the shower.

[deleted]
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