The Networking Research Group at Microsoft Research has been working on White Fi a system, which accesses the Internet over unused portions of TV spectrum and could provide good long-range connectivity in rural areas, and help fill in gaps in city networks. The FCC has now given a green light to use off so called white spaces (the gaps between TV channels) but there are strict requirements that devices should not interfere with existing broadcasts. The TV spectrum between 512 megahertz and 698 megahertz, which was originally allotted to analog TV channels from 21 to 51, offers a longer range than conventional Wi-Fi, which operates at 2.4 gigahertz. At similar power levels it would give users the potential to access their home router from over a mile away without external dishes or antennas.
According to Microsoft their White Fi solution is designed so that each device measures the spectrum conditions around it and works with the others to find available frequencies. Because interference can happen at any time, the system can move to a different slice of spectrum if need be.
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