Robust Beamformer Using Manifold Separation Technique for Semispherical Conformal Array

Conventional beamformers suffer from problems of finite samples, desired signal pointing errors, as well as imperfect array. A simple and robust beamformer based on the manifold separation technique (MST) is proposed in this letter to alleviate these problems. Using MST, the steering vector of an arbitrary array can be modeled as the product of an array sampling matrix and a vector with a Vandermonde structure. Robust characteristics are found by using this transformation. The analysis is verified via simulations based on a real-world semispherical conformal antenna array.

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