Retrofit Anti-Jam CRPA for Handheld GPS Receivers

Toyon Research Corporation proposes to design a low-cost, jammer resistant antenna element suitable for legacy handheld GPS receivers. The design will mechanically and electronically interface with the handheld unit and require no change to the receiver.This active antenna device will provide 35 to 40 dB of improvement in the J/S (jammer to signal) ratio. The design itself will use Toyon's innovative electronically reconfigurable antenna (ERA) techniques. Such antennas make use of active control loaddevices in the antenna aperture. These devices enable the antenna characteristics to adapt to the signal environment. Toyon has considerable experience in ERA design and the design and fabrication of the associated control devices and processes. For thisArmy handheld application, we have taken Toyon's innovative anti-jam GPS antenna design approach and developed new innovative control techniques that allow it to retrofit the existing PLGR (AN/PSN-11) receiver. The jammer resistant GPS antenna proposed forthis handheld unit will fit in a package that is 4-inches long and one inch in diameter. At the end of Phase I a proof-of-concept breadboard version of the antenna will have been designed, fabricated, and tested for its suitability as a GPS CRPA withanti-jam capabilities.Applications range from military applications, including the obvious handheld Army GPS antennas to commercial GPS applications. This electronically reconfigurable antenna concept is applicable for any commercial application of GPS,which is subjected to electromagnetic interference such as business aircraft or helicopters flying in and out of populated areas.