After a four-year competition, Lockheed Martin Corp. won a Navy contract worth up to $3.3 billion yesterday to develop satellites that could help soldiers and sailors communicate.

Bethesda-based Lockheed will build as many as five satellites under the contract, said Leonard F. Kwiatkowski, vice president of military space at the company. The narrow-band satellites would enable a soldier in the jungle or a sailor in a submarine to receive maps, video and other data as well as speak to command centers through a handheld device, he said.

While the general trend is toward high-frequency satellites, this program addresses the needs of tactical fighters, said John Pike, director of GlobalSecurity.org. "These channels don't have much more capacity than a dial-up modem," Pike said. But "if I am a little special ops team and I am out in the middle of nowhere and would like to download the latest situation report, I just flip this baby out of the backpack and I am in business. . . . This is like satellite communications to the fox hole."

The Mobile User Objective System will supplement, then replace, Ultra High Frequency satellites now used by the Navy. The first satellite in the series is expected to be launched in 2010.

The contract could be worth more than $6 billion if the Navy buys more satellites as expected, industry analysts have said. Lockheed beat Raytheon Co. for the contract. The program is one of the last large military satellite competitions left, analysts said, and is important because there are few contracts available in the commercial market.