Figure 4: Synthetic Aperture GPS Signal Processing

FIGURE 4: Synthetic generation of a two-dimensional phased array: Physical one-dimensional (1D) arrays are used to steer the beam in the first dimension (beam direction is collinear to the planar surface that is perpendicular to the direction of platform motion); 1D arrays at different spatial locations are applied for beam steering in the second dimension (beam direction is collinear to the planar surface that is parallel to the direction of motion); measurements of individual antennas are combined for phased array processing. Note that the 1D physical antenna arrays can be implemented on a single platform or can exploit multi-platform implementations such as multiple autonomous aerial vehicles (UAVs).