A simple calculation method for the self- and mutual-radiation impedance of flexible rectangular patches in a rigid infinite baffle

A numerical model has been developed to calculate the self- and mutual-radiation impedance in the cases of uniformly and flexibly vibrating rectangular patches in a rigid infinite baffle. The spatial convolution approach is employed here to derive general expressions for the radiation impedance of a rectangular radiator in the form of simple integrals, which allows a fast evaluation numerically. The presented integral solution agrees with that obtained for the mutual-radiation impedance of a uniformly vibrating rectangular piston by the use of the classical approach. The numerical results of self-radiation impedance of a square piston are compared with the tabulated values published previously. As examples of flexibly vibrating rectangular patch, a closed-form expression is first given for the radiation impedance in the normal mode of vibration. The numerical results reveal that the computation time in obtaining accurate calculations is greatly reduced by using the proposed method.