Defense Department researchers are testing a state-of-the-art radar system that someday would give troops a better look at potential adversaries, at White Sands Missle Range, N.M. The Joint Land Cruise Missile Defense Elevated Netted Sensor System (JLENS) incorporates tethered, helium-filled aerostats that are loaded with sophisticated surveillance equipment. Stationed at 10,000 feet, the JLENS aerostats will be able to provide ground troops, vessels, and aircraft pilots with 360-degree views of battlefields. They will have the capability of locking onto targets and feeding their positions to air defense systems.