Near Space Fills Communications Gap

Signal, Nov 2005 by Lawlor, Maryann

Four teams traveled from Phoenix: One headed west toward San Diego; one traveled east toward Deming, New Mexico; one went north toward Flagstaff, Arizona; and one proceeded south toward the Mexican border. The demonstration proved that connectivity could be extended from the usual 10 miles for line-of-sight communications in that type of terrain to more than 400 miles. "Also, it doesn't matter how many operators you have on that network. You could have 100 operators on there and they're all using that communications frequency relay, and everybody would be connected in that particular footprint," Col. Lane notes.

The colonel admits that even the battlelab staff did not expect to be able to maintain the communications link at a distance of 400 miles. The radios were used at a relatively lower power setting, 3 watts, and Thales estimated that the theoretical communications range at that wattage would be around 300 miles. "We think we could have pushed much, much farther, but we had teams going all the way toward San Diego so we were limited and kept it at that footprint," he relates.

To assess communications quality, the battlelab team used four categories: loud and clear, good and readable, weak but readable, and weak and unreadable. Even at more than 400 miles, the signals were still good and readable, Col. Lane says. Shadowing resulted in weak and unreadable signals, he adds, but this is the same problem that satellite communications systems encounter, and operators collected data so the issue could be reviewed.

In addition to the ground teams, the effort showed how radio-equipped balloons can support tactical air patrol parties. A-10s, F-16s and Joint Surveillance Target Attack Radar System aircraft were employed, and the battlelab team proved that not only were air-to-ground and ground-to-air communications possible but also users on the ground could communicate with aircraft on the ground. This is "a very nice capability," Col. Lane says, because personnel can communicate with an aircraft while it is stationed on a runway. This capability is especially beneficial for the A-10 that relies on ultrahigh frequency communications, he notes.

The team also operated in secure mode for the air-to-ground link, and because the radios on the balloons are only repeaters, cryptology equipment is not necessary. "So if we don't get them back, for whatever reason, it's not as big a deal as if you're flying actual crypto material," the colonel offers.

Ron Irwin, senior systems engineer, Scitor Corporation, worked with the battlelab on the demonstration, and he emphasizes how this technique supports operational responsiveness. "With satellites, you can't decide that you're going to launch another satellite right now," he says. "And we're just touching on the capabilities of this kind of technology. This is a capability that the field commander doesn't have to ask anybody's permission to use. He just floats communications whenever he needs to and at a price that's so cheap it's going to revolutionize beyond-line-of-sight communications."