Analytical representation of transient aperture near- and far-fields

The considered investigation is concerned with a method which is able to account for every aperture geometry of an aperture antenna, taking into account arbitrary nonuniform distributions. The investigation makes use of an approach reported by Cagniard (1939). The mathematical formulation of the problem is considered, and an analytical representation of a certain potential response is obtained. The response can be easily computed numerically for observation points located in the near-field and in the far-field region. Numerical results for a uniform rectangular aperture are discussed, and numerical results for ultrasonic phase-arrays are reported.