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

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.

Comments

1000x better than blue tooth LE

[goombah99]

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.