A method includes displaying a reference polar coordinate system on a display screen, and displaying a radiation pattern image on the display screen in juxtaposition with the displayed reference polar coordinate system. In another aspect, an angled line is drawn on a display screen to represent the proposed layout of a leaky coaxial cable. A point of interest is selected that is spaced from the proposed cable layout, and one of the segments of the cable is determined as likely to produce a dominant level of irradiation with respect to the point of interest.