An upgrade for CDMA 1xRTT networks that provides up to four times greater capacity.

In most CDMA networks, 1xRTT (and 1x Advanced) is used for voice and text messaging, while 1xEV-DO (and/or LTE) - using its own dedicated radio frequencies - it used for data. Therefore the benefits of 1x Advanced apply mostly to voice service.

The four times greater capacity means that a network upgrading from 1xRTT to 1x Advanced can handle four times as many voice calls using the same radio spectrum. Or - more likely - it can handle the same number of voice calls in one-fourth the radio spectrum, freeing up radio frequencies (bandwidth) for additional 1xEV-DO or LTE service, to handle growing demand for high-speed data service.

To achieve the full four-times capacity boost, all phones must support 1x Advanced as well. Carriers see some immediate benefit when upgrading network towers to 1x Advanced, but only realize the full four-fold capacity boost over time, as consumers upgrade to newer phones that support 1x Advanced.

A 1x Advanced network can optionally be configured by the carrier to provide greater coverage compared to 1xRTT, at the expense of the improved capacity benefit.