Imagine your cell phone warning you about air quality that can be very bad for your allergy or asthma. Also imagine your cell phone being used to detect or ready any sensor or perform any diagnostic function anywhere regardless of cell phone service availability. Well a company called Gentag has a patent titled "Method and Apparatus for Wide Area Surveillance of a Terrorist or Personal Threat." Gentag has a unique portfolio of patents and intellectual property, technology development experience, and established relationships with industry leaders in manufacturing and customer support for wireless, passive, active and semi-passive sensor technologies.Gentag (http://www.gentag.com) has technologies to program mobile devices to detect virtually any kind of chemicals in the environment, from pollen and carbon monoxide to the noxious gases dispersed by criminals or terrorists.

Gentag's broad patent covers the uses of personal wireless devices such as cell phones, PDAs, pagers, or watches as low-cost customizable wireless-sensor readers to detect external environmental threats for consumer, industrial, and Government applications.

How It Works Gentag’s vision is that anyone will be able to do diagnostic testing directly on a cell phone. This is now possible through:

• The integration of sensors with low-cost RFID technology,
• The use of cell phones and PDAs to become readers for any type of sensor,
• The use of Gentag’s proprietary non-GPS geolocation technology to precisely locate sensors or sensor events.

Integration of Sensors

Sensor technologies that are small, sensitive and suitable for integration into a cell phone or an RFID chip are becoming widely available. Gentag’s patented concepts allows for interchangeable sensors modules on a cell phone itself or sensors that are directly incorporated into an RFID tag that can be read by a device such as a cell phone or PDA.

Modified Cell Phone Technology

Following the events of September 11, 2001, Gentag filed several patents to expand its modular “smart” wireless sensor and triangulation technologies first described in US Patent 6,031,454 to cell phones and other wireless devices, thereby combining smart sensors with geolocation.

Cell phones can serve as universal wireless sensor readers, thereby creating a new type of flexible and low cost wireless “active tag” sensor platform technology with a number of commercial and Homeland Security applications.

Non-GPS Geolocation

Gentag’s geolocation technology was developed at Sandia National Laboratories and field-tested by the US Department of Defense. The technology is a stand-alone system that can be applied to virtually any wireless technology by calculating either signal time-difference-on-arrival or by angle-on-arrival. The technology has the following three advantages:

• The first is that the calculations are done ex-situ (i.e. at the base station of the transmission system), meaning that the device that needs to be geolocated can be very small, have low power requirements and be of low cost.
• The second major advantage is that existing systems (such as cell phone transmission towers) can be used as a basis to deploy the technology.
• A third advantage is that the technology works under cover (e.g. in large cities). Field tests from Sandia show that the technology is competitive with GPS.