Pattern Optimization of Wing-Mounted Array Antennas at UHF

摘要

A systematic design procedure for high frequency wing-mounted antenna systems by means of a digital computer has been undertaken in this report. In particular, the design of an antenna system to give full hemispherical coverage in the aft region of an aircraft for quadrant detection at UHF has been of concern. The principal objective of this study has been to determine the number and placement of elements and their excitation for arrays on the surfaces of the wings for a specified pattern. The constraints that are imposed are the frequency, element type, aircraft, stores and sector of coverage. Classical array techniques are used to find the array parameters. The placement of the array on the wings are determined with numerical aircraft models developed using the Geometrical Theory of Diffraction. Measurements of a single slot element on an F-4 aircraft were taken to compare with the calculated results. Although the results are not directly comparable because the measurements are in the near-field and calculations are in the far-field, the results are encouraging. A method to present the volumetric pattern for an antenna mounted on an aircraft has been used to aid the system designer in viewing the performance of the antenna system in all space. The method is based on displaying different directive gain levels by different colors on a two-dimensional graph. (Author)