Frequency-invariant and low cross-polarization pattern synthesis for conformal array antenna

Conformal array antennas will find their potential and promising applications in a variety of fields ranging from space-borne, airborne, ship-borne, and missile-borne radar, space vehicles and wireless communications to sonar, etc. They present many new challenges to the antenna designer, including varying element normal due to curvature, serious cross-polarization effect and limited operational bandwidth, etc. Frequency-invariant pattern synthesis of conformal array with low cross-polarization is of great importance for the future conformal array applications. A uniform method for the element polarized pattern transformation of arbitrary 3D conformal array is presented based on Euler rotation. A space-time-polarization filter construct is proposed for frequency-invariant and low cross-polarization pattern synthesis of conformal array. The optimal weight vector is obtained with alternating projection method. Simulation results are provided to demonstrate the effectiveness and behavior of the proposed method.