Can you cohere me now?

University researchers are developing a means by which private cell phones could be enlisted to help detect and track radiation in order to prevent terrorist attacks with dirty bombs or nuclear weapons.

"This system will allow first responders to rapidly locate and track an individual transporting radioactive materials intended to be dispersed in some populated area," said Ephraim Fischbach, a physicist at Purdue University.

Purdue physicist Ephraim Fischbach (r.) works with Jere Jenkins, director of Purdue's radiation laboratories, on a system that uses the cell phone networks to detect and track radiation. (Purdue photo)

These constellations of cell phone detectors, combined with proprietary software methods, override the limitations of basic single-point detection. Large numbers of detection nodes in the field transmitting real-time data to a processing center can treat whole geographic areas statistically in ways impossible for individual detectors located at single points, Fischbach said.

"Data from cellular nodes include precise spatial coordinates along with radiation levels, converting data sets into low-light photographs of complete geographical regions." he said.

The system was developed by Andrew Longman, a consulting instrumentation scientist, who developed the software for the system and then worked with Purdue researchers to integrate the software with radiation detectors and cell phones.

This is not the first time the idea of using the cell network has been suggested in homeland security schemes; other groups had previously proposed putting detectors in cell phones. Fischbach told Homeland1 that what makes his system unique is the software that allows officials to coordinate the information from many detectors at the same time and then use this information to locate a moving source.

Ultimately, Fischbach envisions a layered approach with hundreds of millions of inexpensive detection nodes streaming data, and hundreds of thousands of more expensive spectrographic nodes adding on.

"It must be emphasized that inexpensive and simple detectors in ubiquity must be the first goal because of the overpowering effect that algorithmic detection can have when ubiquitous node presence is achieved," he said.

Fischbach said his system also solves the problem of false positives.

"The nature of ubiquitous detection methods demonstrates that the longer the system runs, the more accurate it becomes in discerning a signal," he said. "Therefore, the proliferation and size of the network serves, over time, to continually reduce false positives."

Getting some cell phone users on board might be a lurking problem. Those people with concerns over brain tumors from cell phone use might flinch at the thought of their device being used for anything even remotely connected with radiation.

"Since this system detects radiation, we hope that citizens will understand that it will be playing a positive rather than a negative role with respect to radiation," Fischbach said.