Non-Iterative Multi-Aperture and Multi-Illuminator Phasing for High Resolution Coherent Imagin

The maximum resolution of a multiple-input multiple-output (MIMO) imaging system is determined by the size of the synthetic aperture. The synthetic aperture is determined by a coordinate shift using the relative positions of the illuminators and receive apertures. Previous methods have shown non-iterative phasing for multiple illuminators with a single receive aperture for intra-aperture synthesis. This work shows non-iterative phasing with both multiple illuminators and multiple receive apertures for inter-aperture synthesis. Simulated results show that piston, tip, and tilt can be calculated using inter-aperture phasing after intra-aperture phasing has been performed. Use of a fourth illuminator for increased resolution is shown. The modulation transfer function (MTF) is used to quantitatively judge increased resolution. The analytic MTF is compared to an "experiment" MTF using the slant edge method. Though experimental proof has been elusive, experimental process has been described as well as some possible reasons why the experiment was unsuccessful.