Okay never mind don't read my sources. This 3D printed Plastic is using backscatter techniques. I'll just quote the article and realize your not understanding where this invention is coming from and why this is new worthy and not just some wifi reflections.
"To 3-D print objects that can communicate with commercial WiFi receivers, the team employed backscatter techniques that allow devices to exchange information. In this case, the team replaced some functions normally performed by electrical components with mechanical motion activated by springs, gears, switches and other parts that can be 3-D printed — borrowing from principles that allow battery-free watches to keep time."
...
"Information — in the form of 1s and 0s — is encoded by the presence or absence of the tooth on a gear. Energy from a coiled spring drives the gear system, and the width and pattern of gear teeth control how long the backscatter switch makes contact with the antenna, creating patterns of reflected signals that can be decoded by a WiFi receiver."
I read your sources. Nothing you quote here contradicts what I said if you read it in the context of the entire paper. E.g. " creating patterns of reflected signals that can be decoded by a WiFi receiver." isn't technically wrong, but very misleading, since what they analyse for data is the signal strength the receiver sees across the packets, not the content of the packets. That's why we are arguing that they present it terribly.
A Wifi packet is a few milliseconds long at best, it should be obvious why a 3D printed mechanical thing can not be fast enough to change bits in there to actually generate a new packet.
Please note that I'm not claiming that it's not using backscatter techniques, that it isn't novel or that it isn't interesting. Backscatter is a generic enough term to cover all these things, despite them being quite different.
I'm claiming that it does not generate Wifi packets. It merely changes their physical characteristics in a way that can be detected, without changing anything about the packet contents.
> I'm claiming that it does not generate Wifi packets.
How does the Wifi transmit how much laundry soap or any measurement if it wasn't new packets???? Maybe if you can just look at this for 2 minutes you'll understand how this is new packets? https://youtu.be/4tmatoD0I1o?t=14m5s
It has to be received and transmit data. Your assuming a reflection is what's happening. Than a mirror could also do the same thing?
This is your laptop or Smartphone able to receive a signal from a 3D device with no new hardware using only the power of a Wifi transition signal that a Wifi receive will read.
That link has nothing to do with what we're discussing here. The video is about active electronics. The article being discussed here is about variable reflection of RF signals based on pure mechanics and zero electronics.
The project discussed in this article is exactly like a mirror, but for RF. If you'd attach a mirror to a spring and had it rotated back and forth with a cog-like thing, you'd have built the exact same thing they're presenting here, except for light. You wouldn't want to call it "Li-Fi communication" just because the mirror can reflect the same frequencies Li-Fi devices use, though. Which is why calling this project a "Wi-Fi device" is wrong.
As a former research librarian I have to say please check why in the world you are going down this path. It is 100% a Wifi device that is sending new packets. There is zero chances that what you are assuming to be true would work.
They are called in the published paper "printed Wifi devices, Wi-Fi input widgets, 3D Printed Wi-Fi Smart Objects." If your smarter and see how stupid or misleading these Phds are and MIT for publishing these finding then do it. Otherwise you are basing your whole argument on incorrect presuppositions and you didn't do any due diligence to see your missing knowledge how these actually work. How in the world would you send measurements to a Wifi receiver in your laptop? You would send a measurement of test tubes to a laptop without any electronics and no dc power.
Read how this is done for measuring wind speed:
"We 3D print a cup anemometer as shown in
Fig. 2 to measure wind speeds. The entire setup is sufficiently light that even wind speeds as low as 2.3 m/s will cause it to spin. The hub of the anemometer is attached to backscatter gear that encodes an alternating sequence of zero.
I understand your missing the similarities in the projects but they are all related by the same principles. The 3D printed Wifi devices (plastic adn metal, are doing what is normally requiring circuitry.
Achieving data communication using push buttons requires us to address two unique challenges: 1) we need a mechanism to identify the beginning of a packet, and 2) since users can push buttons at different speeds, we need an algorithm
for symbol synchronization.
On page 242:5, it explicitly says that it doesn't send new packets.
> In our case, the backscatter signal is a
narrowband transmission embedded on top of the ambient Wi-Fi
signals, since the printed Wi-Fi objects send data at a low data rate.
Even your quoted text doesn't say that it sends packets IMO.
Please explain how it works in as simple terms as you can?
My explanation:
The 3D printed Wifi device uses plastic and metal to connect to any Wifi receiver (normal laptop or smartphone) using any commercially available Wifi transmitter. 3D device uses it's antenna to send new data. The data is sent uses reflection and absorption of the Wifi signal to create new data of 1s and 0s though at a slower rate of speed. This is all done without the need for batteries or other electronics. There is no special hardware or software besides the 3D device to connect and send data. The device can toggle an electronic switch to either absorb or reflect an ambient signal to convey a sequence of 0 and 1 bits using reflective and non-reflective states. This is accomplished by leverages present Wifi backscatter technology but for the first time instead of using electronic components these 3D devices use non-electronic and printable analogues.
> "embedded on top of the ambient Wi-Fi signals,"
That is how backscatter works and how they connect to wifi and send specific 1s and 0s. It absorbs and reflex a wifi signal out of those absorption and reflections.
It can't work without some signal to carry on top of it and could work with a single 2.4 sine wave. But backscatter absolutely sends measurements to a normal Wifi rx aka a phone or laptop through the Wifi transmitter.
"To 3-D print objects that can communicate with commercial WiFi receivers, the team employed backscatter techniques that allow devices to exchange information. In this case, the team replaced some functions normally performed by electrical components with mechanical motion activated by springs, gears, switches and other parts that can be 3-D printed — borrowing from principles that allow battery-free watches to keep time."
...
"Information — in the form of 1s and 0s — is encoded by the presence or absence of the tooth on a gear. Energy from a coiled spring drives the gear system, and the width and pattern of gear teeth control how long the backscatter switch makes contact with the antenna, creating patterns of reflected signals that can be decoded by a WiFi receiver."