Letter Never Sent

I haven’t seen anything in the mainstream media lately about Iraq using cheap GPS jammers to mess with the US military’s techno-dependent weaponry. Because of inertial targetting systems the most GPS jammers seem to be able to do is cause GPS-guided weapons to land off target by 100 feet or so. I have not seen anything about these Russian built jammers have affected ground troops or if the Iraqi military are using these at all. It’s likely the US is trying to maintain their image of invulnerability.

I wonder if governments are developing means to not only jam GPS receivers and transmissions but to decrypt transmissions and substitute the locations and coordinates of enemy targets to make them vulnerable to friendly fire. GPS could be used in this way to create battle confusion. Illusions of forces and units as one possible example.

Some links of interest:

1. FOX SPECIAL REPORT WITH BRIT HUME January 10, 2003: Satellite Jamming
2. Iraq Can Jam Guidance Of US ‘Smart’ Weapons 1/14/03: The global positioning system, developed for the U.S. military, consists of a constellation of 24 satellites that continuously beam navigation signals that can be used by anyone with the proper receiver. The satellites transmit two signals, one available to civilian users, including commercial airliners, to determine their position within a distance of a few metres. The second signal, for use by the military, is encrypted. The Air Force placed GPS receivers on previously “dumb” gravity bombs as a way to enhance their accuracy. Once dropped from an aircraft, the bombs use GPS signals to locate a specific geographical location up to 15 miles from the drop site. GPS-guided JDAMS bombs were used in Kosovo and also in Afghanistan.

   The GPS signals from the satellites are weak and can be overwhelmed by a broadband transmitter that generates enough “noise” at the right wavelengths, experts said. “I would tend to believe that you could jam those encrypted signals with enough power,” said Linn Roth, president of Locus Inc. of Madison, Wis., a maker of radionavigation products. “Those signal levels are so low.”
   

3. U.S. sends mixed signals: military admits its technology is vulnerable:
   Iraq may have also bought Czech or Ukrainian acoustic sensors that can uncloak stealth aircraft. Or it could scatter heat-generating decoys that fool heat-seekers on missiles and infrared sensors on aircraft.

   These tactics have been seen before. The Serbs used them to blunt NATO attacks in 1999. …

   Low-tech ingenuity could also come in handy, with air defense crews scanning night skies for attacking aircraft using spotlights powered by diesel generators – impervious to failures of the electrical grid, said Michael O’Hanlon, defense analyst with the Brookings Institution. …

   A Russian company, Aviaconversia, has exhibited GPS jamming systems at military trade shows, claiming they could cripple GPS systems throughout Iraq. The $4,000 devices on display were less worrisome than powerful GPS jammers apparently available on the international arms market, said Bob Martinage, an analyst with the Center for Strategic and Budgetary Assessments.

   “We know our GPS systems are vulnerable to jamming because we’ve jammed them ourselves with disturbing ease,” said Hewson of Jane’s. “If you don’t know where you are, you have a real problem.” …

   Despite NATO’s sophisticated sensors and guided weapons, the Serbs safeguarded most of their planes and tanks by replacing them with decoys crafted from plastic sheeting, tires and logs. Some decoys cradled heaters that mimicked engine emissions.

   NATO bombed hundreds of the dummies. Yugoslavs also simulated troop positions with portable heaters left on empty hillsides to dupe infrared sensors. Had a ground war been ordered, NATO would have faced a largely intact Yugoslav army.

   “Our sensors haven’t improved in any significant ways since Kosovo,” O’Hanlon said. “You can try to be aware of decoys, but that doesn’t help if you can’t tell the difference between the real thing and a fake.”

   Serbs also greeted NATO air attacks by firing simple anti-hail rockets – meant to warm hail-bearing clouds and make them rain, said Jeremy Binnie, an Iraq analyst with Jane’s Information Group. Although the basic rockets posed little harm to aircraft, pilots who saw them on radar often aborted their missions, Binnie said.

   “Certainly the Iraqis have been working on these techniques, using civilian areas to shelter troops, mixing military vehicles with civilian ones, learning to confuse our surveillance,” said Anthony Cordesman, a military analyst with the Center for Strategic and International Studies.

   Some speculate that Iraq may even be able to uncloak radar-evading U.S. aircraft like the F-117 Nighthawk fighter and the B-2 bomber.

   The State Department alleged in November that Iraq obtained stealth-exposing Ukrainian radar that can triangulate an aircraft’s position by the sounds it makes. Analysts say it’s also possible Iraq got a similar Czech-made system called Tamara.

4. ‘Smart war’ gamble put to test: The jamming scenario � and also “spoofing,” sending out a fake GPS signal to confuse the bomb and make it miss its target � has been hotly debated in the months before the war. …

   A Russian company, Aviaconversia, has hawked a portable eight-kilo transmitter at airshows that, it says, denies commercial GPS reception to a range of 200 kilometres around.

   But the Pentagon says the military GPS signal would be harder to interrupt than the civilian; that anyone who sent out a jamming signal would themselves be easy to spot and counter-attack; and that some bombs have been fitted with anti-jamming software.

   I don’t know. That sounds like a bluff. You could easily imagine unmanned, remotely operated GPS jammers.
   

This entry was posted on Saturday, March 22nd, 2003 at 12:15 pm and is filed under Military and defense. You can follow any comments to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.