BOSTON — The U.S. Air Force manages its basic satellite and rocket acquisition programs from Los Angeles, but the service is tapping its electronics experts in the Boston area to upgrade a ground-based orbit-surveillance system inherited from the U.S. Navy.

Management of the Space Fence surveillance network was only recently added to the responsibilities of the Electronic Systems Center (ESC) at Hanscom Air Force Base, Mass., which also develops some of the ground-based systems that provide forces with access to data from satellites and other platforms.

ESC, originally known as Electronic Systems Division, is primarily responsible for developing and managing complex platforms and systems for command and control; information handling; and intelligence, surveillance and reconnaissance. Its program portfolio includes various ground- and airspace-surveillance aircraft.

Now ESC has a key piece of the increasingly important space-surveillance business via the Space Fence, a network of nine radar stations deployed across the southern United States that track low-orbiting objects as they pass overhead. The Navy, which had managed and operated the Space Fence since its inception in 1959, handed that responsibility to the Air Force in 2004.

The Air Force also assumed responsibility for upgrading the system’s performance, a nod to heightened concerns over potential threats to the satellites on which the U.S. military heavily depends. Raytheon Integrated Defense Systems of Tewksbury, Mass., won a $396 million Fence upgrade contract in 2002, but that work stalled, initially due to an Air Force proposal to shut the system down entirely.

Talk of shutting down the Fence in favor of other space surveillance systems, based both in space and on the ground, has since died down. But the upgrade plans are in a state of flux.

Air Force Lt. Col. John Brendle, Space Fence manager with the 850th Electronic Systems Group at Hanscom, said that in light of the U.S. military’s growing emphasis on space surveillance, the service now plans a new competition for upgrades that will go farther than the Navy had planned.

Currently the Space Fence, consisting of VHF-band radar stations, is capable of detecting and tracking objects about the size of a basketball in low Earth orbit. Raytheon’s Navy contract called for the company to replace those radars with S-band systems capable of tracking baseball-sized objects.

Now the Air Force is thinking about a system that also can track objects the size of a beachball in medium Earth orbit, where the GPS navigation constellation — which these days is critical to both civilian and military users — operates, Brendle said. In addition, the service is contemplating adding stations outside the United States to improve the Space Fence’s ability to determine whether orbiting objects are maneuvering, he said.

Brendle declined to say where these outside stations might be located.

Once the upgrades are completed, Brendle said, the number of objects tracked by the Space Fence will grow from the current number of 10,000 to about 100,000.

But the Air Force, citing other funding priorities, late last year deferred program upgrades. Previously the service planned to issue a request for proposals for the effort in November 2007. Now the solicitation is not due out until July 2008, with a contract award expected the following January, Brendle said.

ESC also is actively involved with ground systems that enable troops in the field to access information from a variety of intelligence platforms. One example is the Air Force’s version of the Distributed Common Ground System (DCGS), where ESC is bringing a new capability on line called the DCGS Integrated Backbone, according to Air Force Col. Alan Tucker, commander of the 950th Electronic Systems Group.

The upgrade is intended to make it easier for military personnel to search for intelligence data, Tucker said. Relevent pieces of information are often difficult to find in large intelligence databases, in part because the different military services and agencies use different formats to tag data for search and retrieval, he said.

The DCGS Integrated Backbone upgrade uses keywords like a specific target or event of interest, or a certain geographic area, Tucker said. The system also sends out alerts to users interested in particular targets or geographic areas, in much the same way that travel Web sites send out alerts about special hotel rates or airfares for a particular destination , he said.

The ESC has added these new capabilities to DCGS systems at four sites : Langley Air Force Base in Virginia, Beale Air Force Base in California, Hickam Air Force Base in Hawaii, and Osan Air Base in South Korea, Tucker said. A similar upgrade at Ramstein Air Base in Germany is expected to be completed in late April, he said.

Electronic Systems Center at a Glance

PRIVATE colorchange:<c”Black”>Headquarters: Hanscom Air Force Base, Mass.

Commander: Lt. Gen. Charles L. Johnson

Parent Organization: Air Force Materiel Command

Current Budget: $4.3 billion

Personnel: 9,500 including military and civilian personnel

Mission: Develops, acquires, modernizes, and integrates network-centric command and control; intelligence, surveillance and reconnaissance; and combat support information systems to provide commanders with battlefield situational awareness and other key information.

Year Established: 1961, as Electronic Systems Division. Renamed Electronic Systems Center in 1992.