Most of Monmouth's work involves invisible signals that make BlackBerries, walkie-talkies, cell phones, radar and even remotely detonated bombs work. All of the technology that sends, receives and decodes these signals once filled row after row of metal racks in many of Monmouth's labs.

Now, government and private-sector engineers have reduced a cell phone network to an Army green box that fits under a desk.

Workers at Monmouth's personal communications lab deployed two of these boxes to Louisiana in the days after Hurricane Katrina, when New Orleans' cell phone network was obliterated.

The team distributed 500 cell phones to emergency personnel and placed one box -- essentially the guts of a cell phone tower -- at Louis Armstrong International Airport and another at the New Orleans Naval Air Station. Those 500 people, however, could talk only to each other until engineers at Monmouth's space and terrestrial command linked them to satellites at the post and then to Verizon's local network in New Jersey.

"Under cell phone towers are miles of fiber-optic cables," Martin said. "The cell user doesn't see that, and that doesn't exist in the Third World."

Electrical engineers here also are working to eliminate traditional, cumbersome radio antennas and replacing them with cell phone-size antennas that are embedded in helmets.

The most secretive part of Fort Monmouth's work involves technology that jams detonators on car bombs, one of the most common threats to U.S. forces in Iraq.

Mechanical engineers in the base's production shop -- a small factory with huge machinery that bends metal and punches holes -- are building video-conferencing equipment capable of functioning inside a box in the back of a commander's Humvee, part of a project called Mounted Battle Command on the Move.

Workers also are trying to secure them against hackers and spies and make all of this technology easy for a soldier with basic computer knowledge to use.

Many of Monmouth's labs have white tile floors. The walls are lined with rack after rack of computer hard drives, some with red, green and yellow lights that blink or rise like a sound board at a rock concert.

Wires spill out of computers. The ceiling of the software engineering lab is nothing but exposed ventilation shafts and metal beams holding hundreds of seemingly endless multicolored wires.

Many labs house old and new Army green transport trucks, in which all of this mobile equipment must fit. The new technology must be able to talk with the old technology, as well as systems developed for other branches of the military.

The military of the far future, however, is being designed in two very different types of labs. One is called a "virtual prototyping facility" -- a small square room painted black except for a movie screen.

Inside the black room, engineers project an image of a Humvee they are designing on the screen and then slide on 3-D glasses. The image suddenly pops out. Wearing black gloves with wires attached to the fingertips, a designer can reach into the 3-D Humvee, pick up a radio stored in the back of it and set it down on the front seat.

'The Cave'

Monmouth's second 3-D lab is called "The Cave." Ron Kane, the project's leader, clicks a button on what looks to be a television remote control. Floor-to-ceiling movie screens rotate into the shape of the top half of a hexagon, forming a stage.

Wearing 3-D glasses, Kane and members of his team watch 3-D G.I.s run across the screen. The video-game style background is of Fort Dix, N.J., and it is so detailed that the brand of the trash bins behind one of Dix's buildings is visible. The virtual soldiers are participating in a battle exercise.

In the near future, engineers hope to use The Cave for mission rehearsals and after-action reviews. In the far future, the Army hopes to be able to watch 3-D versions of battles as they happen.

"We would be able to see beyond the hill, while the soldiers couldn't," Kane said.