Phased arrays operating in a near field environment

An adaptive methodology is presented that not only can deal with realistic antenna elements operating in a real environment, but also can handle the effects of mutual coupling between the antenna elements. In addition, one can incorporate in this methodology the effects of near field scatterers and use of dissimilar antenna elements in the array. The analysis is carried out using a dynamic electromagnetic analysis tool. In addition, an array transformation technique is used to mitigate the various complex electromagnetic effects in a non-uniformly spaced non-planar array in the presence of mutual coupling and the problem is transformed to that of a virtual linear array of uniformly spaced isotropic point radiators operating in free space. The preprocessed data from the interpolated virtual array is analyzed using a direct data domain least squares approach utilizing a single snapshot of data to estimate the strength of the signal of interest arriving from a known direction in the presence of coherent strong jammers, clutter and thermal noise. In addition, this methodology is quite amenable to real time processing.