Battery-Free Cell Phone
techradar.com
techradar.com
Which makes this all the more impressive!
The Thing actually needed power to operate, btw. The power was just beamed in externally.
> Right now the battery-free phone needs a custom base station to transmit and receive calls. But the team says there's no reason why the technology couldn't be integrated into standard mobile network infrastructure.
This could only be called a cell phone, if the cell phone network changes to accommodate this radio. It's not a cell phone, because it doesn't work with cellular phone towers.
Those applications are called medical alert systems, and there are various kinds. Some of the systems contain GPS, while other work with a radio base station to inform if the person has fallen and can't get up.
For example, http://www.best10medicalalertsystems.com/
I'm not even sure if multiple of these devices could be used simultaneously like traditional cellphones, which change frequencies/channels as they move between cells and to avoid collisions with other mobiles. Judging by their description, it works on a fixed frequency and the "phone" itself has basically no active circuitry, being nothing more than an analog audio-to-RF modulator.
> Anyway, Cellphone just means it can handle hand offs between base stations without dropping the call, which this could do.
No. It literally cannot do that, hence my comment.
Of course it could be changed into a cellphone!
The device on this page is billed as a cellphone, but it is not a cellular device. It is not even a phone.
Of course it could be made into a cellphone, just as my shoe could be made a cellphone. In the interim, neither my shoe nor this radio is a cellphone.
But you may have missed this part "or ambient light collected by a solar cell the size of a grain of rice". So, yes they built a cellphone, even if they can't gain power from arbitrary sources.
> But you may have missed this part "or ambient light collected by a solar cell the size of a grain of rice". So, yes they built a cellphone, even if they can't gain power from arbitrary sources.
A cellphone is not "a radio that cannot connect to a phone network and that uses a solar cell". That would be a solar-power radio.
But, this also handles dialing to make Skype calls so it's not just a radio.
Wrong. This communicates with a base station that made skype calls. This is a radio.
You sound as if you have a vested interest in continuing to mislabel this device.
There are a ton of things this device does that are cheesy, because they are trying to push the limits on low power. But they could have jacked up the received power by 30x and fooled most people reading, but they actually did create something novel by pushing almost all functionality to the base station.
It the use case is IMO not general calls it's more like a limited call 911 when battery is dead mode that could still be useful.
A cellphone that doesn't work with cellular network cells and isn't a phone really shouldn't be called a cellphone. It's a passively-powered radio.
EDIT: This Wired article has a lot better information:
https://www.wired.com/story/this-cell-phone-can-make-calls-e...
"... Some key components of Talla's phone are housed remotely to save power. A nearby basestation has circuitry for converting and connecting to the digital cellular network, currently via Skype. The prototype basestation uses an unlicensed frequency, limited to low-power transmissions. Because the phone relies on those signals for its energy harvesting, it has a range of just 15 meters from the basestation."
And it looks like they use backscatter, which would be "transmitting" signal and not using a side-channel.
Youtube has some videos about a thing called ampy, a tiny case you attach on you. I'm not sure it made it to market though.
3.99 with free shipping.
Does it mean the voice is transmitted in plaintext using analog modulation of (reflected) carrier wave? Privacy concerns aside, how can it handle calls from multiple stations over same frequency range?
Don't you need to keep draining power produced by solar panels? What about the heat problem and decreasing efficiency of solar panels?
It is also due to leakage currents from capacitors, and any leakage that might go out through GPIOs. Sensors also have a static draw when not in use. Batteries self-discharge. And so on.
For example, a cc1310 system on chip has a 0.8uA current consumption when in deep sleep, but the real static draw is more than that. Periodically, the chip will run a little charge pump to energize RAM so that it doesn't evaporate (metaphor). There might also be a timer active, and that consumes 100uA. And so on.
When the device wakes up to run at 24 MHz, it uses about 1.9mA, plus any peripherals (SPI 13+93uA, timer 113uA), plus any sensors or other hw peripherals. This might be very very short amount of time, like 10 ms every two hours-kind of short.
So it turns out, that for a device that wakes very rarely, the static draw can be a significantly decrease lifetime. It's small, but it is _always_ there. It is hardware-dependent and is the "black art" within embedded development. It's very easy to reach arduino-levels, pretty easy to start using low-power modes, time/money-consuming and requires expertise to squeeze the last years/months out of the battery.
I don't know if this is uncool to ask I'm also late a few days to respond.
With regard to connection to the web generally (to my knowledge) you need some way to communicate say send a POST request to some API and I'm not sure if this means that you need an OS which when I think of an OS you need to keep it on or even with sleep... I don't know. I don't know if you can design hardware/firmware meant to interface with the web, still be programmable and simple/light on resource without a full blown OS like raspberry pi.
Anyway thanks much to learn.
Yeah, connecting to the web can be stressful to a small device, but it's very feasible. A basic OS that handles timers, a communication stack, a way to abstract tasks and communicate between them, can be quite small. Contiki OS for small devices can run on tiny devices - the amount of RAM and flash and CPU speed isn't much a limiting factor until you start with communication. Then you want RAM to hold queues of packets, neighbor tables, etc. You want flash to hold the code necessary to use the protocols you need. We support a range of devices at Thingsquare, eg the cc1310 with 128kB flash and for that we have space for a full-fledged IPv6 stack and all that's necessary for low-power wireless (ie specific radio duty cycling protocol, routing protocol, etc), our own libraries and abstractions to make it simpler for customers to use the system, with room left for customer application and drivers.
Contiki OS is event-based, ie when it is not actively doing something, it simply waits (for something to happen on a physical pin, or radio event, or timer expiry) and can go to sleep. That way, and with lots of hard work to make everything efficient on every level, you save power. Raspberry pi and similar ones makes it simpler (lots of developers know the stuff, linux, etc) but has drawbacks (power, complex system, lack of low-level control and kernel timing requirements might not suffice, cost, IP, in some cases security, licensing, etc).
Have a look at these: http://www.thingsquare.com/blog/articles/sensortag-power/ and http://www.thingsquare.com/blog/articles/ti-cc1350-power-con...
Yeah it's much easier from my lerspective/experience tojust throw on Python/PHP on there and do stuff granted that's more "webserver" I didn't mention databases but you could just write to filesystem (txt) and my intent was transmission.
Contiki OS sounds cool
Anyway I'll refer back to this post, thanks.
Do you know any off the self components which can fully operate on 100mA?
It runs on 3.5uW, and the homemade cellphone I built last year with off-the-shelf components drew 2A when syncing with GSM antennas.
Some people don't realize it, but GSM is very expensive power-wise, especially on boot when it has to find antennas. Having a device that can be solar powered or even with ambient radios is extremely useful!
Right now the battery-free phone needs a custom base station
to transmit and receive calls. But the team says there's no reason
why the technology couldn't be integrated into standard mobile network infrastructure
There's obviously many reasons. Transmission range, security, privacy, reliability, ...
Can you burst with capacitors or no? (Not a hardware person)
I’m always confused by people complaining about iPhone battery life. My wife’s iPhone 6 lasts days, it’s called a battery pack. And she gained this incredible battery life without forcing me to carry a heavier bulkier iPhone. That’s what Apple understands, making their devices heavier and thicker to please a minority of users while inconveniencing the majority makes no sense when battery packs exist.
Naturally GPS would be right out...
Pretty sure the potential market size is in the single digits, but I'd be happy.
I could use this in my spy operations though. Not that Im a spy or anything.
Definitely, not a spy.
I'd love a device that ONLY does sms or text based comms (fb, whatsapp etc..) but only the text. and nothing else.
that would sip battery.