Bethesda-based defense and aerospace giant Lockheed Martin has agreed to acquire Zeta Associates, a Fairfax-based information technology company, the two announced this week.

This is Lockheed’s second recent acquisition; in June, it agreed to acquire Deposition Sciences, a Santa Rosa, Calif.-based company that makes thin film technology.

Zeta Associates makes software and hardware that converts airborne signals to a digital form for intelligence and defense customers. For instance, the company makes radio-frequency switches, synthesizers and other products.

The transaction, whose terms were not disclosed, is expected to close in the third quarter of 2014.

“Zeta Associates’ expertise in cross-platform information collection, analysis and dissemination is an ideal complement to our national security capabilities,” Marillyn Hewson, chairman and chief executive of Lockheed Martin, said in a statement.

Zeta Associate’s technology could help the company deliver ground, air and space-based intelligence support, she said.

Zeta Associates has about 350 employees based in Fairfax and Denver, Colo., among a few other customer locations. Lockheed does not currently have any plans to move the employees — Zeta will become a wholly-owned subsidiary after the acquisition closes, according to the company.