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Apple Patent Hints At Wirelessly Charging Your iPhone Via Wi-Fi Routers (appleinsider.com)
According to AppleInsider, "Apple is experimenting with medium- to long-distance wireless charging technologies that could one day allow users to charge up their iPhones with nothing more than a Wi-Fi router." From the report: Detailed in Apple's patent application for "Wireless Charging and Communications Systems With Dual-Frequency Patch Antennas" is a method for transferring power to electronic devices over frequencies normally dedicated to data communications. In its various embodiments, the invention notes power transfer capabilities over any suitable wireless communications link, including cellular between 700 MHz and 2700 MHz, and Wi-Fi operating at 2.4 GHz and 5 GHz. More specifically, the document's claims apply to millimeter wave 802.11ad spectrum channels currently in use by the WiGig standard, which operates over the 60 GHz frequency band. Theoretically, the proposal opens the door to wire-free charging from in-home Wi-Fi routers to cellular nodes and even satellite signals. Of course, amplitude in a wireless system is normally a function of distance. Like conventional wireless charging techniques, Apple's design requires two devices -- a transmitter and receiver -- to function. Each device contains one or more antennas coupled to wireless circuitry capable of making phase and magnitude adjustments to transmitted and received signals. Such hardware can be employed in dynamic beam steering operations.
Remember that your router is limited to 1W output (FCC limits in the US for all 2.4Ghz and 5Ghz devices), fired in every direction. At a mere 1 meter away from the router, even if your cell is placed facing the router (to have maximim surface area), and assuming 100% efficiency... your cell would harvest about 0.0004 watts of charging power.
But it will not be 100% efficient. Your cell will not be within 1 meter of the router most of the time. This entire idea is ludicrous, and anyone thinking that it's a great idea does not know much about physics.
Time for a round of choose the hypothesis:
#1 - Out of the 10,000+ engineers working for Apple, not even one of them knows about physics.
#2 - At least one of them knows not only about physics, but also some other type of technology that would actually validate the patent filed (somehow).
#3 - Patents for patents sake. Even fake news is still a (click) revenue generator. Oh, and is there an app for patents yet? 'Cause we need some patenty app goodness!
Ironic how "dumb" phones have removable batteries that last for a week, and "smart" phones have non-removable batteries that struggle to last a day.
These "lots" of energy you are talking about are not nearly enough for a modern smartphone.
How many times does this need to be repeated? You are NOT going to be able to collect significant energy by rectifying radio transmissions, unless you plan on collecting for a long, long time. Put another way, your phone is using up the battery WAY faster than you would be able to charge it from wifi, broadcast and whatever other RF you might run across.
EVEN with beam steering, where the whole half-watt of power from the router is aimed directly at your phone, you are up against:
- your inefficient receive antenna
- the inverse square law
- path loss
It's not practical. Why Apple is filing a patent on this, I don't know.
"Ironic" how smart phones have a battery that lasts for a day despite having them having far more memory and far more computing power than a Cray 1 supercomputer which needed a 115 kW power supply.
It's almost like comparing radically different technologies isn't a useful comparison.
Lol 1/r^2 is all that saves us from being fried. Why don't you put your solar panels 1 meter from the sun surface and see how that goes.