| 摘要 |
<p>A cavity (12,14) with a plurality of notches (16,18,20,22) formed in the edge of the open end. Each notch is fed to establish a notch-type antenna. Notches at 90 DEG angles from each other are formed for a monopulse application. A coaxial feed line (30,32,34,36) is used where the outer conductor is connected at one side of the notch and the inner conductor at the other side. The sizes of the cavity and notches are selected to radiate energy of a selected frequency bandwidth. Additional cavities (48,50,52) of different sizes for radiating different selected frequencies are nested concentrically together to form a multifrequency antenna array with a common phase center. Each cavity has a plurality of notches and each cavity may be rotated in relation to the adjacent cavity to misalign the notches between the two cavities and thereby increase isolation between frequency bands. <IMAGE></p> |
