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.
These units were trialled for a period of time in both the US and UK by T-Mobile, and 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.
Fully compliant under the February 2013 Safe Harbor 2 issued by the FCC: On February 20th 2013, the FCC released a Report & Order, thus establishing two Safe Harbors and defining the use of “network safe” consumer boosters on licensed spectrum. The Safe Harbors represent a compromise solution between Technology Manufacturers and Wireless Operators. It is widely considered a landmark decision which was many years in the making.
Cel-Fi has an LTE/4G/3G product. It was launched in September 2014.
- "Mobile Phone Signal Boosters » Cel-fi RS2 from Nextivity". 20 April 2012. Retrieved 20 April 2012.
- Faas, Ryan (October 27, 2010). "T-Mobile quietly testing Cel-Fi femtocell alternative for customers in signal-challenged areas". IT World. Retrieved Feb 12, 2011.
- Ockenden, Paul (May 14, 2010). "The legal ways to boost your mobile phone reception". PC Pro. Retrieved Feb 12, 2011.
- Scardino, Francis (October 26, 2010). "T-Mobile Currently Testing Cel-Fi Signal Booster to Maximize 3G Data Service In Homes". Gear Diary. Retrieved Feb 12, 2011.
- "Nextivity Aims to Boost Indoor Cell Phone Signal". San Diego Business Journal. Advanced Technology Ventures. November 21, 2008. Retrieved Feb 12, 2011.
- "Nextivity And NETGEAR Collaborate For Indoor Mobile Coverage Solutions". Business Wire (Press Release). Feb 2, 2010. Retrieved Feb 12, 2011.
- "Nextivity Cel-Fi 3G signal boosters – available from Frequency Telecom". PR Log (Press Release). June 4, 2010. Retrieved Feb 12, 2011.
- "Video: T-Mobile 3G Cel-Fi Signal Booster Unboxing (junkdruggler)". YouTube. Retrieved Feb 12, 2011.
- "What is a mobile signal repeater and is it legal to use one?". Cel-Fi UK. Retrieved Sep 26, 2011.