Created by Nextivity, Inc., the Cel-Fi systems are designed with smart antenna technology to seek out the best available signal to maximize signal gain to phone users. The Cel-Fi consists of two wireless devices, a Window Unit and Coverage Unit that work jointly to increase 3G and 4G mobile broadband connectivity throughout the building. The window unit receives the signal and relays it to the receiver, which converts it and amplifies it.
Trialed for a period of time in both the US and UK by T-Mobile. Approved in UK by T-Mobile and Orange in 2011 and O2 in 2012. Cel-Fi systems are comparable to cellular repeaters and femtocell technology. In October 2012 the Cel-Fi system was the first and only signal boosting device to be approved for use in Australia.
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