According to recent media reports, students at the University of Washington have recently developed a new kind of WiFi technology and its selling point is the limited consumption of energy. With less than one ten thousandth of the current Wifi energy, this technology can effectively reduce battery drainage and even allow for reverse Wi-Fi networking equipment that charge on the go. Part of the MIT Technology Review, this technology has already been nominated into the Top Ten breakthroughs of 2016.
While IoT or Internet of Things is probably the biggest emerging technologies yet to grace the consumer market, there is some concern that the true power of IoT is still a decade away. It is believed that by 2020, nearly 50 billion products will be interfaced with each other in an interconnected family governed by the Internet. The problem with such a magnitude of interfacing is that almost all such devices will need a constant power source to at least operate the Wi-Fi signals. From sensors to mobile phones, power is paramount to the success of IoT.
This is where the new idea and innovation comes handy as it allows devices to acquire energy from traditional television and radio signals. Basically, the sensor will work on wearable devices and several low energy units that can operate without batteries or wires. Because their power consumption will be pretty nominal, they can actually be kept active for years with a single battery or even charged off radio signals!
Called the Passive Wi-Fi technology, the routers used for this purpose are no different. They just happen to be highly energy efficient. At present, the transmitting power of a traditional router is about 100mW whereas a Passive router will need only 10 to 50 microwatts, which is a millionth of the current requirement.
The technology used is similar to that of RFID chips, Wi-Fi backscatter. Basically you end up reflecting radio waves. As project researcher Wami Si explains, with Passive Wi-Fi devices instead of transmitting signals, they will be only reflecting Wi-Fi packets thus using much less power.
There are three steps necessary as per the researchers to make passive Wi-Fi work. Step one is to install a device in your home. This will basically transmit analog waves to a passive wi-fi sensor. Majority of the power is used in this stage whereas the passive wi-fi sensor does not use any power.
In step two, the sensor will take up the analog signal and convert it into digital signals generating necessary WiFi packets. This device will then broadcast at 11Mbps speeds, which while slower than broadband, is much faster than Bluetooth. Your phone or router will pick up the signals from here.
With this technology, Wi-Fi will no longer need batteries! Read more straight from University of Washington Passive Wi-Fi website