5GE, or 5G "Evolution" is the name that AT&T is using in areas where 4G LTE technologies like three-way carrier aggregation, 4x4 MIMO, and 256 QAM are available. These features making existing wireless networks faster, provided your smartphone supports them.
These are technologies that have already been in place on AT&T's network and networks from Verizon, Sprint, and T-Mobile. Your phone has probably already been connecting to AT&T's LTE networks with these capabilities even before AT&T added its 5GE icon.
AT&T, in fact, started rolling out support for these technologies in 2017, as did other U.S. carriers.
AT&T says that in areas with these upgraded LTE technologies, customers can reach peak theoretical wireless speeds of up to 400 megabits per second, but in real-world usage that ends up being closer to 40 megabits per second.
These are LTE speeds that are available on many other carriers to customers using modern devices.
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