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‘Passive Wi-Fi’ Costs 10,000 Less Energy

passive wifi

Although Wireless Internet (Wi-Fi) allows users the convenience to stay connected in various places, it quickly drains a lot of energy and shortens the battery life of most smartphones, smartwatches, and other smart gadgets. Fortunately, there is a modern alternative to this Wi-Fi woe. During the recent 13th USENIX Symposium on Networked Systems Design and Implementation (NSDI) in Santa Clara, California, USA, engineering students and computer scientists from the University of Washington have discovered a solution, which they termed as “Passive Wi-Fi.”

This new device, which has won the Best Paper Award in the NSDI, uses Wi-Fi connection with 10,000 times less energy than the conventional Wi-Fi chipsets in the market and is 1,000 times less power-intensive than Bluetooth LE and ZigBee technologies. It transmits Wi-Fi signals at transfer speeds of up to 11 megabits per second, which can be decoded on any devices with Wi-Fi connectivity and can communicate at a distance of up to 100 feet. This current speed is lower than the maximum Wi-Fi speeds, but it is 11 times faster than the usual Bluetooth connection.

Extends Battery Life

With Passive Wi-Fi, there is significant extension in battery life usage. The battery life of mobile gadgets that often use the current Wi-Fi and Bluetooth technologies may last only three years. In contrast, the use of passive Wi-Fi can triple the normal battery life of smartphones and other mobile devices. MIT Technology Review hailed the invention as one of the Top 10 2016 Breakthrough Technologies. Jeeva Wireless will soon commercialise the new Wi-Fi device.

How does it work? 

The research team has discovered how to separate the digital and analog operations that are involved in radio transmissions to achieve low-power Wi-Fi transmissions. The passive Wi-Fi assigns the analog’s power intensive functions, such as producing a signal specific frequency, to a single device in the network that is plugged into the wall. Various sensors using very little power produce Wi-Fi packets of information through reflecting and absorbing the signal using a digital switch. This stream of reflected or backscattered signal transmits the data of up to 802.11b speeds or 11 Mbps.

Why does it matter?

Aside from its battery saving advantage, passive Wi-Fi communication that uses almost no power can help make the Internet of Things (IoT) into reality, where household appliances, mobile devices, and wearable sensors can all communicate using Wi-Fi without worrying much about energy consumption. It can also emerge as an alternative and even phase out Bluetooth. This development makes it an ideal solution for the IoT connectivity and eliminates the need for a battery. Furthermore, Passive Wi-Fi connection has the potential of helping appliances, lights, and other home accessories become more affordable, energy-efficient, and get connected to the Internet.

Stay tuned to learn more useful tips on how to get the best possible connection at home. To get the best Internet plans for your home, you can visit our Plan Guru or call 13 22 88 to speak to our 100% Australian advice specialists.

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