US operators face rising capital costs, slowing revenue

Wireless carriers are facing increased capital investment needs as they race to handle surging data traffic, just as maturing industry penetration and more competitors offering the Apple Inc. iPhone begin to dent revenue growth. AT&T has been selling smartphones mostly to existing subscribers as the company added fewer new mobile customers than rival Verizon Wireless -- a joint venture of Verizon Communications Inc. and Vodafone PLC -- in the fourth quarter.

While the popular iPhone helped stanch customer losses at Sprint Nextel Corp. in the fourth quarter, hefty subsidies for the device contributed to its wider fourth-quarter loss. Meanwhile, T-Mobile USA's lack of the iPhone has hampered its ability to draw and retain customers. The Deutsche Telekom AG unit -- reeling from an exodus of customers and the failure of its planned sale to AT&T last year -- plans to cut 5% of its workforce and close seven call centers to help fund its $4 billion network upgrade to the faster mobile broadband service known as 4G LTE.