Radiation field of conformal arrays can be obtained by simulation computation. There must be a trade-off between computation accuracy and complexity. With respect to applications where both high efficiency or even real-time applications and accuracy are required, such as adaptive beamformers together with time-varying array structures due to deformations or vibrations, more effective methodologies have to be employed for precise mainlobe direction maintenance and rigorous suppression of existing interferences. A method combining spherical mode expansion, rotation and translation of spherical waves, spatial displacement phase compensation, and approximations of constant element radiation patterns in local coordinate systems is proposed here, featuring one-time numerical effort for isolated element radiation patterns, fast coupling matrix calculation based on updated array configuration, and analytical radiation field expressions with limited eigenmode expansion coefficients storage requirements. Adaptive beamformers are utilised to validate the effects of remaining approximations including constant element patterns in local coordinate systems and constant mutual coupling matrix, proving the proposed method has the potential for aircraft-borne conformal antenna array radiation field analysis where deformations and vibrations occur continuously.

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Element phase centre and orientation compensation in conformal arrays during continuous deformations based on spherical mode expansion

References

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