SEM representation of the early and late time fields scattered from wire targets

In the communication, the singularity expansion method (SEM) is used to express the field scattered from an arbitrary thin-wire target. Explicit expressions are given for both the class-1 and class-2 representations of the scattered field due to step excitations. Numerical results are given for the early-time transient fields scattered from both a straight wire and a simple swept-wing aircraft model. The results of the SEM computations are compared to fields obtained by Fourier inversion techniques. It is shown that the class-2 representation yields a significant improvement over the class-1 result during the early-time interval, albeit at the expense of a more complex computation