Correction to ´Short-pulse excitation of reflector antennas´

In a previous paper (see ibid., vol.134, no.6, p.557-9, 1987) the transient build-up and decay of the radiated field produced by a short pulse in a reflector antenna were examined. The decay time and build-up time were shown to be the same, but the sidelobe level and directivity transients were different. As the far-field receives contributions on-axis from currents on all parts of the reflector simultaneously, due to the equal path property of parabolic reflectors, questions have been raised on this apparent conflict. This brief correspondence shows that the path lengths are not equal for the pattern points except on-axis, and that transient build-up and decay do occur.<>