The U.S. Army is so appalled at the increasing incidence of electronic devices interfering with each other, unexpectedly, that they have begun training specialists to detect, and fix, the problem quickly. Each army combat division now has specialists trained and equipped to do this.
Meanwhile, the problem is growing worse, and every nation with complex military electronics is encountering it. Last year, for example, Indonesia ran into it with the three Su-30MK2 aircraft they had just received from Russia. These are two seater aircraft, with the second crew member handling weapons systems and taking some of the workload off the pilot on long missions. While on a training mission, one of the Su-30s thought it had spotted, on their radar, some other unidentified, and possibly hostile, aircraft. But there was nothing there. Russian technicians checked out the aircraft. It was determined that some of the other electronics in the aircraft, used in a certain combination, were triggering the false radar warning.
There's been a lot of this sort of thing in Iraq. Last year, the U.S. Navy found its Silver Hawk UAVs are getting disabled by interference from other military electronics nearby. This sort of thing has been happening in the region for two decades now. During the 1990 campaign to liberate Kuwait, it was discovered that certain combinations of airborne jammer frequencies could trigger an involuntary launch of Patriot anti-aircraft missiles, as well as some other less catastrophic, but equally unexpected events.
Investigation of these early incidents revealed something electronic warfare experts have been warning of for a long time. With so much exotic new gear, capable of putting out so many different signals, and in a huge number of combinations (which creates even more new electronic signals), there was no way to knowing what kind of impact this would have on existing military, and civilian, electronics. Throughout the 1990s, the problem only got worse. This became obvious as there were increased incidents of military electronics tests trashing, or playing with, nearby civilian electronic devices.
The military has been seeking solutions, because it's important for military equipment, especially communications and control systems, not to suffer electronic interference. In Iraq, is was quickly discovered that Warlock (a jammer that shut down enemy use of wireless signals to set off roadside bombs) also interfered with some military equipment, including some radios. This was not good. Such interference has occurred in the United States when this gear was turned on for training. There partial solutions to these problems, and that's the best anyone can provide so far.