John Keller, Editor in Chief
Improvised explosive devices (IEDs), the specific name for many of the roadside bombs that commonly kill soldiers and civilians alike in dangerous regions of the world, have been among the most dangerous threats in contested areas of the Middle East.
Among the reasons that IEDs are so dangerous are their easy and inexpensive manufacture and detonation. Terrorists throughout the region apparently find it stunningly easy to obtain artillery shells, missile warheads, mortar rounds, and other high explosives for quick conversion to IEDs.
The terrorists simply rig them with cheap RF detonators and bury them where military convoys or other targets of opportunity are likely to pass by. When the targets are in range, they trigger the explosives with radio signals from cell phones, garage-door openers, or other easily obtained devices.
Most often nobody is in evidence at the explosion site-except the victims, of course-so military forces and civilians typically are forced to endure the frustration of standing by, powerless to do much other than mourn the losses of their comrades and neighbors.
That is until now.
U.S. Marine Corps personnel in Iraq are using commercial off-the-shelf (COTS) handheld spectrum analyzers from such companies as Rohde & Schwarz in Munich, Germany, and Boonton Electronics in Parsippany, N.J., to sniff out, pinpoint, and retaliate against those triggering IEDs with cell phones, garage-door openers, or other RF devices.
The handheld spectrum analyzers used, such as the Rohde & Schwarz handheld Spectrum Analyzer R&S FSH, are nonruggedized, commercial-grade, off-the-shelf devices that were never designed for the harsh temperatures, dust, and shock of military operations in the Middle East.
Still, the imperative for the Marines and other fighting forces to make use of what is available as quickly as possible has been the driving force for bringing COTS hand-held spectrum analyzers into the military theaters of Iraq and Afghanistan.
Boonton also offers the 9102 hand-held spectrum analyzer that could well be a candidate for counter-IED operations in Iraq and elsewhere.
Devices like the Rohde & Schwarz R&S FSH and the Boonton 9102 are designed for field operations, but perhaps not to the demanding requirements of the military. Typical users are cell-phone- tower repair personnel, radio technicians who are adjusting antenna arrays, and even U.S. Navy personnel seeking to calibrate the forests of antennas on the decks of modern warships.
“We designed the handheld spectrum analyzer for technicians to climb a mast and check an antenna,” explains Pete Sakell, the government, military, and aerospace business development manager at the Rohde & Schwarz office in Columbia, Md. The company introduced the R&S FSH device in July 2005.
The handheld spectrum analyzers were designed with broad capabilities in mind, but it’s likely that no one ever imagined what these devices could provide for Army and Marine Corps convoys whose members sometimes have to fight for their lives in IED-related ambushes.
These spectrum analyzers enable fighting forces on the ground to detect cell-phone and garage-door-opener RF emissions at the moment they are sent. This yields valuable intelligence information about the RF frequencies that terrorists use to detonate their IEDs.
Armed with this intelligence, convoys can start sending out jammers that broadcast strong “white noise” signals in the RF spectra where the IED detonators operate, which can render the IEDs useless and keep military convoys and other targets safe. “The military can send out a convoy with a jammer to prevent the RF trigger from detonating IEDs,” Sakell explains.
Handheld spectrum analyzers in the hands of fighting forces in the field may be helping military leaders to devise a variety of counter-forces to the IED threat.
“There are two modes to a jammer, active and passive mode,” Sakell explains. “You can have a white-noise generator in the 2 MHz to 2 GHz range, or you could have a smart jammer that simply listens for a trigger signal, and then respond in that frequency range.”
For refining methods to counter IEDs, some of the handheld spectrum analyzers also can emit RF signals, which in normal operations are used to test commercial RF equipment.
For security reasons, Sakell cannot go into detail about how, where, and why U.S. military forces are using the Rohde & Schwarz handheld spectrum analyzers to help safeguard against terrorist attacks. He does volunteer, however, “Has it been effective against IEDs? We have been told good things.”
As effective as these handheld spectrum analyzers appear to be for military forces in the field, the jury is still out on how well these devices will hold up to the environmental extremes of Iraq and Afghanistan-particularly against never-ending exposure to the talcum-power-fine dust that permeates the region.
Rohde & Schwarz’s Sakell says his company has no immediate plans to produce a version that is more rugged than the R&S FSH, but says he is open to ideas and potential partnerships with companies like DRS Tactical Systems Inc. in Palm Bay, Fla., which are experts in ruggedized packaging for COTS electronic devices.
The notion of a military-rugged hand-held spectrum analyzer in wide use among fighting forces in the field certainly tickles the imagination, and may well give rise to new applications that haven’t even been thought of yet.
