Scattering by cylinders in translational motion

The Fourier spectrum of the signal scattered by cylinders in translational motion is evaluated. The incident wave is a plane wave. Both perfectly conducting and dielectric cylinders are considered. Particular attention is given to the low-frequency limit. The spectrum turns out to be continuous, and evidences two (infinite) peaks, at frequencies ¿i(1 ¿ ß cos ¿ i)(1 ± ß)-1.