This is from this weeks Aviation Week and Space Technology.

Stealth Provides Tough Target for Cell Phones

"Specialts on stealth say a cellular telephone-based detection system that reputedly can detect stealth aircraft within an accuracy of 30 ft has so many flaws that it would be less effective than a 1960's-era air defense sensor like the Soviet built Flat Face radar.

A British newspaper reported that the mobile telephone mast system developed at Roke Manor Research in Romsey, Hampshire, can spot disruptions in calls moving between base stations. Lockheed Martin has been working on a similar passive system, called Silent Sentry. It exploits from the FM radio and television stations that are reflected by an aircraft, revealing its location.

However, U.S. Air Force specialists say a cell-phone based system would have a short detection range because of its low power output. Morever, such short-range systems are subject to a high rate of false identifications, which would make target tracking a nightmare. They contend that such a system would not be worth developing because radars actually do a better job. Older, low-frequency radars builtl by the Soviet Union during the Cold War can actually pick up traces of stealth aircraft, but without sufficient accuracy to direct an antiaircraft missile to within lethal range of the target. In fact, some foreign-built antiaircraft systems have switched to optical and infared terminal guidance to provide a better chance of finding and striking a stealth aircraft without the aid of radar. U.S. Air Force analysts suspect the missile that downed an F-117 during the 1999 Kosovo war had optical guidance, which refined a faint radar indication that the stealth aircraft was flying a predetermined route departing Belgrade. But they primarily credit the Yugolsav's use of a missile salvo, one of which detonated close enough to bring down the F-117.

Furthermore, Air Force officials say the cell-phone technique would have several weaknesses. It would be subject to jamming and decoys, and the strongest emitters in the system could be destroyed in the preemptive stages of an attack. Perhaps most interestingly, an Air Force official said that a class of directed energy weapons has been developed to render passive coherent location systems (PCLs) impotent. High explosives wrapped around an electric charge in a coil can be exploded to produce a squirt of high-power microwaves powerful enough to disable electronic systems. To date, the Air Force has experimented with such a system, at least using an air-launched cruise missile. Other directed-energy weapons are in development."

So, it would seem that while the use of cell phone masts are technically possible, they wouldn't work in the real world. It seemed to me that the U.S. Air Force was already well aware of this type of tracking and deemed it impratical and inefficient, already having moved on along with producing weapons to destroy such systems.