Book 3, Question 82
Why Does Wi-Fi Have No Wires?
Wi-Fi is a short-range radio conversation between your device and a box called a router. Instead of a cable, the air carries the data. The router and your tablet agree on a radio channel, and packets of data ride that channel across the room.
From the book
Page from A Million Whys Book 3
More fun facts
- Scientists at CSIRO, Australia's national science agency, patented technology in 1996 that helped make steady Wi-Fi possible.
- Their ideas came from radio astronomy, where they had learned a lot about how radio waves behave.
- The hard problem they solved was moving lots of data quickly around inside buildings.
- In the 1970s, engineer John O'Sullivan got bored analyzing hundreds of cosmic radio recordings, so he invented a chip to do the math fast.
- That chip did a calculation called a Fast Fourier Transform, which breaks radio waves into their separate frequencies and puts them back together.
- During World War II, militaries kept radio messages secret by hopping quickly between frequencies, an idea that later helped wireless networks.
- The CSIRO invention made wireless networks as fast as wired ones of the time, and it is now used in billions of devices.
- By 2012, 23 companies had paid to use the invention, bringing in more than 430 million dollars.
Sources: nma.gov.au
Questions kids ask
Who helped invent Wi-Fi?
A team of Australian scientists at CSIRO, led by John O'Sullivan, who used ideas from radio astronomy.