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Winning Back the Weather Radio Channels Adds Capacity to 5GHz Wi-Fi Spectrum

In my last blog on 5 GHz spectrum, I discussed the recent FCC ruling that permitted outdoor access points to use the U-NII 1 band (5150-5250 MHz).

But the story doesn’t  stop there. As mentioned last time, there are significant technical challenges to using the 5 GHz band. It is not cleared spectrum. It contains incumbent uses that are important for national security and public safety. Therefore, it is imperative that Wi-Fi not create harmful interference to these incumbent systems. Cisco will not settle for less.

On the topic of interference, a particularly interesting component of the same  FCC ruling that opened the U-NII1 band for outdoor AP’s is that it also re-opened the Terminal Doppler Weather Radar (TDWR) band (channels 120, 124, 128) with new test requirements for DFS protection. Hold on, let’s backtrack a bit before diving into what this means:

What is TDWR?

In brief, Terminal Doppler Weather Radar (TDWR) “is a Doppler weather radar system used primarily for the detection of hazardous wind shear conditions, precipitation, and winds aloft on and near major airports situated in climates with great exposure to thunderstorms in the United States.” TDWR uses the frequency band from 5600-5650 MHz which is why wireless network equipment needs to be proven to “do no harm” to TDWR. If you’re curious for more information on TDWR, then please click here and/or here.

A Brief History

Many of you reading this will recall that the FCC closed the use of the TDWR band several years ago as the result of numerous reports of wireless equipment creating interference with TDWR. Read More »

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What, Why, Where, When, How: The New FCC Ruling Around 5 GHz

You don’t need me to tell you to know that we are in the midst of a technology revolution.  It’s mobilizing the internet.  And it’s transforming the way billions of people around the globe collaborate, communicate, and connect to the internet.

•           The education customers I work with are incorporating video and mobile applications into their curriculum with up to a 100 students in an auditorium accessing the Wi-Fi network simultaneously.

•           Healthcare customers are relying on Wi-Fi to connect patients, devices and provide nurses instant access to medical records.

•           Manufacturing customers are increasingly using Wi-Fi to enable workers on the factory floor to have real-time video conversations with experts anywhere in the globe.

What do these things have in common?  They all depend on Wi-Fi for connectivity.  In these areas, and so many more, Wi-Fi has become a central way that people access the Internet.

The FCC released a historic decision on April 1, 2014 (adopted March 31)with regards to the use of 5 GHz spectrum. Although there were many technical aspects included within this decision, one of the most interesting was making the 5150-5250 MHz U-NII 1 band available for outdoor WLAN use. Read More »

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