WASHINGTON, Dec. 18 (Xinhua) -- American telecommunication company AT&T announced Tuesday that its 5G network would go live on Friday in 12 American cities, making it the first wireless carrier to launch a mobile network based on the 5G standard.

However, its 5G service is currently unlike what you are expecting from it. It is only available via a mobile hotspot that converts the network's airwaves into Wi-Fi and then allowing computers, phones and other internet-connected devices to access its ultra-fast network.

The hotspot has peak theoretical speeds of 1.2 Gbps, but "actual speeds will be lower," according to AT&T.

The hotspot works on millimeter wave, a kind of 5G technology, but those high-frequency waves travel short distances and are less able to penetrate walls.

Therefore, the company has to build a large number of 5G radios in the cities to render true mobile service. Also, the 5G-capable phones would not be sold until next year.

AT&T will run the hotspot service in 12 cities: Atlanta, Charlotte, Dallas, Houston, Indianapolis, Jacksonville, Louisville, Oklahoma City, New Orleans, Raleigh, San Antonio and Waco.

The hotspot called Nighthawk will cost 499 U.S. dollars upfront and 70 dollars per month, according to AT&T.