SECOND-ORDER BEAMS OF SLOTTED WAVE GUIDE ARRAYS

Abstract

It is shown that the radiation pattern of slotted wave guide arrays may contain small second-order beams even for slot spacings less than a free-space wave length. These beams are usually split with a minimum or even a null in the plane containing the array and main beam. Since patterns are normally taken in this plane, the second-order beams have until now escaped attention, as far as the writer is aware. Methods of suppressing these beams are discussed.