With each of the country's top four wireless providers investing heavily in their networks, 2013 could be a blockbuster year for infrastructure spending.

ABI Research expects capital expenditures on U.S. mobile networks to rise nearly 5 percent in 2013, to $10.5 billion. Operators are expected to spend about $10 billion on their networks this year.

The research firm based its forecast on operators' LTE expansion plans and operating expenses during the first quarter of this year. 

Verizon has been aggressively expanding its LTE network, which currently covers about two-thirds of the U.S. population. It says its LTE footprint should match its 3G footprint next year. AT&T will also continue adding markets to its LTE build, currently spanning about 50 cities. 

T-Mobile USA said earlier this year it would spend $4 billion to upgrade its network and roll out LTE. 

Sprint is not only deploying LTE, it is spending money on a wholesale overhaul of its 3G infrastructure and the decommissioning of its iDEN network, projects expected to cost the carrier up to $5 billion. 

Clearwire expects to light up its first 8,000 TD-LTE cell sites beginning next year at a cost of about $600 million.

This is good news for the vendors hired to provide equipment for the networks. 

Ericsson and Alcatel-Lucent have contracts to build AT&T and Verizon's respective LTE networks. Sprint has tapped Ericsson, Alcatel-Lucent and Samsung for its LTE deployment. T-Mobile will use equipment from Ericsson and Nokia Siemens Networks. Clearwire has yet to name a vendor for its TD-LTE service.