Robust blind adaptive array. A prototype for GPS

A receiver that incorporates an adaptive antenna array is presented. The system is designed to receive DS-Spread Spectrum signal from the satellites of the NAVSTAR Global Positioning System (GPS) and to operate mounted on a mobile platform. Different from the conventional adaptive antenna for CDMA systems, the prototype presented hereby performs the array processing after the de-spreading. This approach diminishes the data rate provided to the processor that adapts the beamforming, and therefore it allows the use of low cost microprocessor. The adaptive beamforming implements a blind algorithm based on the non-stationarily of the linear modulated digital signals and a pseudo-PRO-ESPRIT algorithm but without any restriction in the geometry of the array. The algorithm estimates the weight vector that achieves the maximum SINR. It is shown that its convergence is faster than Phase-Score, which is the only algorithm with comparable performances. Experimental data that show the performance of the whole system are also presented.