LTE-U and 5 GHz Wi-Fi

LTE has an unlicensed version called LTE-U that uses the 5 GHz U-NII-1 and U-NII-3 bands used Wi-Fi.  The FCC has authorized the first of the LTE-U devices https://www.fcc.gov/news-events/blog/2017/02/22/oet-authorizes-first-lte-u-devices.    What are the implications of this standard?  Will Wi-Fi start having problems on the patio of your favorite coffee shop forcing you to go inside to get a reliable signal?   There is a coexistence standard http://www.lteuforum.org/uploads/3/5/6/8/3568127/lte-u_coexistence_mechansim_qualcomm_may_28_2015.pdf but of course, there is the standard and the actual performance as implemented by device drivers.   

By the way it appears that Wi-Fi vendors such as Aruba, Broadcom, Cisco, Ruckus have been involved http://www.lteuforum.org/uploads/3/5/6/8/3568127/lte-u_introduction_may_28_2015.pdf but I do not know how much of a conclusion to draw from that.    There has been testing against 802.11n http://blogs.cisco.com/sp/cisco-wifi-wi-fi-service-provider-lte-u-by-any-other-name-is-licensed-assisted I have not yet found a reference for testing against 802.11ac that has useful information.  I hope someone can give a better more recent reference that is more reassuring. 

An Aruba networks document http://www.arubanetworks.com/assets/wp/WP_WiFiFirst.pdf also gives me pause, “Because it is a duty-cycle based solution, an LTE-U base station effectively takes control over its channel by force under control of a licensed operator, leaving it up to Wi-Fi to sense when the duty cycle is off.”

I welcome your comments.  

Cool Wi-Fi!

Cool Wi-Fi, or should I say cold Wi-Fi?

A local grocery store left the access panel open to the refrigerated area.  Usually I worry about the other end of the temperature range, but if this is a 3700e model http://www.cisco.com/c/en/us/products/collateral/wireless/3700-series-access-point/data_sheet_c78-729421.html and it looks like the AP is still in spec for temperatures at or just below the freezing point of water.  Of course that raises other questions such as why do they need Wi-Fi in their refrigerator case?   How well do inventory bar-code guns work in that temperature range?

This wireless was foiled

As a wireless person I receive occasional questions about electromagnetic radiation which I just referred to the Environmental Health and Safety department.  Some pictures below show where someone appears to have taken matters into their own hands, but even without the foil I doubt this person was hitting any exposure limits from the AP https://www.fcc.gov/general/radio-frequency-safety-0

Personally it is a little funny that some people worry about exposure from APs, yet will hold a cell phone right next to their head for an extended period of time.

Super Bowl 50

An interesting thing about where I work is that am within sight of Levi Stadium.    Here is a picture I took from the building a few days before the Super Bowl.

The Goodyear Blimp was already flying around the area.   If you are in the area and have a scanner then there are some frequencies you could try to listen to the blimp http://wiki.radioreference.com/index.php/Blimps

While I do not have any predictions as to which team will win, it is a safe bet that a record amount of  data will be transferred over wireless networks.   http://www.techrepublic.com/article/super-bowl-50-to-showcase-new-tech-shatter-bandwidth-records/

This what I saw at the Phoenix Airport last year.  Talk about close!

  

Radio Shack

If you are also into the RF part of communication make sure to stop by Radio Shack before it is too late.  Closing of the stores represents a change in purchasing options, but in the short run it also means some good prices.  I bought some PL259 connectors for about a dollar each today.

Wireless Networking Videos

If you are working on the CCNA or CCNP wireless or any of an number of other wireless certifications such as http://www.cwnp.com/.  It is useful to know that a set of videos by Jerome Henry were just released by Cisco Press.  (Jerome Henry is a well known person in the wireless world.  He has both a CWNE and a CCIE wireless.)  The videos are called Wi-Fi Configuration, Deployment and Troubleshooting LiveLessons True there is material available for free on YouTube, but the quality varies greatly.  

At this point I am about half way through the videos, and would recommend it as a good use of time for anyone in wireless networking.