During the Bank of America Merrill Lynch Media, Entertainment & Communications conference on Thursday, AT&T’s chief financial officer John Stephens said that AT&T will activate its 4G LTE network in its first five markets on Sunday, FierceWireless reported. The network has been active as part of a soft launch in the AT&T’s five markets, which include Atlanta, Chicago, Dallas, Houston and San Antonio, and we have already seen a few glimpses of what the network is capable of. We published an exclusive video on September 6th which showed the HTC Jetstream 4G tablet achieving download speeds around 22Mbps and screenshots of a 4G modem achieving 13Mbps download speeds in Chicago. In addition, we saw the same modem reaching speeds up to 25Mbps in Atlanta. AT&T hopes to activate its network in 15 total markets and launch its first LTE smartphone by the end of the year.