Electromagnetic vs. plane wave models for superdirective 2D adaptive HF receive antenna performance assessment

This paper demonstrated how a 2D planar oversampled HF receive array manifold can be modeled by NEC and utilized to asses the performance of conventional and optimal beamforming techniques. It is shown that the full EM array model behaves similar to a planewave manifold model in the presence of strong non-isotropic external noise. Furthermore it is demonstrated that the optimal beamformer solutions computed with a manifold not calibrated to the true EM manifold will exhibit some amount of mismatch loss in directions of strong external noise. In a subsequent full paper, we will comment further on the robustness of the EM model antenna manifold predication to small model perturbations (i.e. changes in ground conditions, element errors, etc.) and on the efficiency of a number antenna calibration techniques that can be used to avoid the SENR losses associated with antenna manifold mismatch.