Accession Number : ADP004611

Title :   Waveguide Slot Array with CSC(2) Theta - COS Theta Pattern,

Corporate Author : EMERSON ELECTRIC CO CALABASAS CALIF RANTEC DIV

Personal Author(s) : Erlinger,J. J. ; Orlow,J. R.

Report Date : JAN 1985

Pagination or Media Count : 30

Abstract : A planar array of longitudinal shunt slots in rectangular waveguides has been designed to produce a CSC squared theta. COS theta patter in the E-plane and -22-dB side lobes in the H-plane. The array operates at 15 GHz. The choice of E-plane amplitude and phase distribution, to synthesize the CSC Theta. COS theta pattern shape over the sector 8 degrees to 50 degrees below broadside, involved a tradeoff study. The widely used Woodward approach of superimposing a family of uniform-amplitude/uniform-progressive-phase distributions on the aperture was studied but not used in preference to a technique reported by Elliott of perturbing the roots on a Chelkunoff unit circle to obtain the desired pattern shape. Twelve roots were perturbed in a systematic way to obtain an optimum amplituude distribution with accompanying phase angles. The paper also describes a method used to spread the resultant E-plane distribution and the H-plane Taylor distributioon over a circular aperture. The mutual coupling between elements was taken inot account for the design. The predicted results show good agreement with measurements.

Descriptors :   *SLOT ANTENNAS, *ANTENNA RADIATION PATTERNS, *ANTENNA ARRAYS, *WAVEGUIDES, SIDELOBES

Distribution Statement : APPROVED FOR PUBLIC RELEASE