WASHINGTON — Satellite ground terminal manufacturer Gilat Satellite Networks on March 17 announced it is purchasing privately held mobile satellite antenna builder Raysat Antenna Systems for $25 million in cash as part of Gilat’s stated policy of bolstering its product portfolio for business with the U.S. Defense Department.

Gilat said the transaction is likely to take up to six months to close and will not have a material impact on the company’s 2010 revenue. Vienna, Va.-based Raysat will be merged into Gilat’s Spacenet Integrated Government Solutions division, created in late 2009 to broaden Gilat’s market from commercial and civil-government business to appeal to U.S. defense and other government agencies.

Petah Tikva, Israel-based Gilat, which had a difficult 2009 as the market for its very small aperture terminal, or VSAT, satellite terminals was hit by the economic downturn in much of the world, had nonetheless accumulated more than $100 million in cash above what is needed to operate the company’s business.

Gilat Chief Executive Amiram Levinberg, announcing the creation of the government division in late 2009, said the U.S. Defense Department market for satellite ground gear is about as big as the commercial market for corporate VSAT networks.

Raysat has developed low-weight, aerodynamic terminals intended for on-the-move communications for both military and emergency response and for commercial use.

“This partnership will lead to a new level of high-speed, highly mobile communications for the military, emergency response organizations, and other markets with a need for fast, flexible, on the move communications,” Levinberg said in a March 17 statement. “We look forward to addressing new opportunities with Raysat in the government and military markets.”

Gilat said Raysat Chief Executive David Gross, former president of DRS Technologies, will remain with the company as part of the Spacenet management team.

Peter B. de Selding was the Paris bureau chief for SpaceNews.