In this paper, eigen analysis of the correlation matrix for an 8-element singly curved conformal antenna array with plane wave(s) incident at different angles is presented. The signal eigenvectors derived from the correlation matrix are used as the array weights to generate peak beams toward the directions of the signals, and the noise eigenvectors derived from the correlation matrix are used as the array weights to generate nulls in the directions of the signals. A 1 x 8 microstrip patch antenna array is embedded on an anhedral corner type structure with different amount of surface deformation to analyse the array pattern. The patch antenna elements in the conformal array are excited with attenuators (for amplitude control) and phase shifters (for phase control) to implement the complex signal eigenvectors practically. The simulated eigenbeams using conformal antenna array are in good agreement with the measurement results. Furthermore, the effects of surface deformation on gain and beamwidth of array main beam is discussed. The proposed eigenbeam conformal antenna array can be used in smart and adaptive array applications.
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