576 THE BELL SYSTEM TECHNICAL JOURNAL, JULY 1951 



Fig. 16 — Removal of the phase signal of Fig. 15 shows more clearly the major lobe of 

 radiation in the shadow of a disc, the "bright spot" of optics./ = 9 KC. 



Fig. 17 — Radiation pattern of two equal sources of low directivity separated 3 wavelengths 

 center to center. / == 9 KC. 



ference in whose directions for which the sources are in phase (such as straight 

 ahead). The interference minima become filled in near the radiators be- 



