Approximate natural response of an arbitrarily shaped thin wire scatterer

An important aspect of radar target discrimination using natural resonances is the ability to discriminate targets with slight differences in geometry such as differences in wing angle and length. To understand the effects of small geometrical perturbations, it is more important to quantify the change in natural frequency than to accurately determine the frequency itself. The authors introduce an approximate but computationally simple technique for calculating the natural response of an arbitrarily shaped thin wire scatterer. The results provide an efficient means of testing target discrimination among nearly identical wire targets. The method is applied to the dominant resonant current modes of thin cylinders known to have nearly sinusoidal current distributions.<>