Radiation coupling of a disk to a plane and back or a disk to a disk: An exact solution

The radiation coupling or coupling by propagating waves is solved for a disk in an infinite baffle to a plane and back or equivalently a disk to a disk both in infinite baffles. The radiation coupling is defined as a linear filter operating between lumped mechanical components which may be incorporated into transducer models. The impulse response of the radiation-coupling filter and the Fourier transfer function for the radiation-coupling filter are solved in closed form. The radiation-coupling gain (loss) is applicable to the correction of experimental data and to the absolute calibration of circular transducers by self-reciprocity measurements.