Analysis and Characterization of Ultrawideband Scalar Volume Sources and the Fields They Radiate

This paper investigates a certain class of threedimensional (3-D) (volume) sources to the scalar wave equation that are capable of radiating high-amplitude short-duration pulses in a selected (main) direction and low-amplitude longduration pulses in other directions. Parameterization and characterization of such sources and the fields that they radiate is carried out in both the frequency and time domains and various measures of ultrawideband radiation (transmit mode) performance are evaluated and discussed within both domains. Frequency and time-domain results corresponding to uniformly distributed parallelepiped sources are presented to elucidate the role of the source’s space distribution on the radiation performance. These results provide insight about the possibility of optimizing the radiation performance of scalar, ultrawideband volume sources by a proper selection of the space distribution of the source.