The Pentagon yesterday said it views ultrawideband wireless transmission as a "significant technology." But like the Federal Communications Commission (FCC), it wants to ensure that widespread use of the new technology doesn't degrade satellite signals from the Global Positioning System (GPS).
Last week, the FCC adopted a proposal to consider operation of ultrawideband (UWB) services on an unlicensed basis, citing the technology's potential for high-speed data transmission over short distances and its ability to detect buried objects.
A senior official in the Office of the Assistant Secretary of Defense for Command, Control, Communications and Intelligence (ASD/C3I) said the Pentagon has "potential applications" in both the sensing and short-range communications areas that could take advantage of UWB technology. But he endorsed plans by the FCC to test the new technology for potential interference before authorizing its widespread use.
The senior Pentagon official, who asked not to be named, said the Department of Defense wants to proceed carefully with UWB because of concerns about the ability of GPS signals to continue working properly.
GPS technology, which is used to target weapons and for aircraft navigation, "is quite weak compared with other authorised radio signals," the Pentagon official said. As a result, he added, technical experts within the Department of Defense are concerned that widespread use of another radio system that intrudes on GPS signals "could have a negative effect" on the performance of GPS systems.
UWB technology uses a broad swath of the radio frequency spectrum, not just a single one. But Ralph Petroff, chairman of Time Domain Inc. in Huntsville, Alabama, last week dismissed any chances that UWB could interfere with GPS signals.
Time Domain has developed a ground-penetrating radar based on UWB that can zoom in on people buried in piles of rubble after an earthquake. The radar transmits only "millionths of a watt over the (GPS band)," Petroff said at the NetWorld/Interop 2000 conference in Las Vegas. "If we interfere with GPS, we don't have a business."
But Jim Lovett, director of strategic polices at Palo Alto, California-based start-up Fantasma Networks Inc.,said his company is so concerned about interfering with GPS signals that it's avoiding any use of GPS frequencies in the UWB-based household wireless systems it's now developing.