SAN DIEGO -- AT&T announced plans Tuesday to upgrade its wireless network in San Diego County this year to improve reliability and enable 4G mobile broadband services.

The company plans to install "backhaul" connections to 500 cell sites that enable data transmission speeds required by 4G users, add capacity to 260 cell sites, install 35 new cell sites and upgrade antennas in key areas such as Balboa Park to improve wireless coverage during special events, Ignacio De La Torre of AT&T said.

About $19 billion will be spend on network upgrades and other capital projects system-wide this year, according to AT&T.

"We're investing in our San Diego network to help AT&T customers take advantage of the numerous capabilities of their wireless devices," said Tammi Terrell, vice president and general manager for AT&T Mobility and Consumer Markets in San Diego.

4G networks are the fourth generation of wireless technology. The faster speed, available only with 4G devices, enables more services for smart phones and laptop computers.