GPS CCM Improvements

In this Phase I effort, we propose to generate a low-cost adaptive antenna elec- tonics system design based on GaAs MMIC components (amplifiers, phase shifters, attenuators, power detectors) and a null-steering algorithm employing a novel direct-search optimization method. This method belongs to the class of the genetic algorithms which optimize a properly selected cost function by generating pertur- bations of the control variables (in this case the antenna weights) so that the adaptation process mimics the biologic process of evolution. The proposed adaptive antenna can be implemented in a standalone interference canceller unit which accepts RF signals at Ll from a number of GPS antenna elements, combines those signals through digitally controlled phase-shifters/attenuators, and delivers an RF signal at Ll to a GPS receiver. This unit includes a TMS32OC31 DSP to implement the antenna algorithm. A prototype interference canceller will be developed and tested in Phase II.