Non-Planar Array 'Thinning' Study

摘要

The report describes an investigation to establish guidelines for designing thinned, nonuniformly spaced array antennas of spherical or hemispherical configuration: Development of generally applicable analytical approximations for the means and variances of the probability density functions for the quadrature components of the field. Previous work had developed estimates valid only for small angles off the main beam. Development of analytical expressions for: (a) the probability density function of sidelobe magnitude anywhere in the pattern, (b) the mean-squared far sidelobes, (c) the probability density function of the 3-db beamwidth, and (d) the sidelobe magnitude not exceeded anywhere in the far sidelobes with a specified assurance. These expressions are all functions of the degree of thinning and of element directivity. Completion of a comprehensive set of computer simulation runs from which ten, independent sample patterns are available for each of several array designs featuring different degrees of thinning and different element directivity characteristics. Preliminary examination of the agreement between the analytical predictions and the computer results. (Author)