A Patch Array for Aircraft

A patch array designed for an aircraft to satellite communica­tion link is described by Sanford (35) and is shown in Fig. 17. Eight patches are mounted together with the phase shifting and feeding circuitry to scan the beam in the elevation direc­tion. Designed for operation at 1.5 GHz, the array, including radome, is 3.6 mm thick. Element phasing was optimized for maximum multipath rejection at low scan angles and to ac­count for the curvature of the mounting surface. Each ele­ment was pointed in a different direction and has an inherent phase error relative to the center elements. A digital com­puter was used to determine how the design parameters actu­ally affect the performance of the array. The spacing of the array elements must be greater than 0.32A (in free space) be­cause the physical size of the radiating element on teflon fi­berglass requires thin space. The spacing required to prevent

A Patch Array for Aircraft

where D is the separation distance between the patch ele­ment, A is the wavelength in free space, and в is the maxi­mum beam steering angle. For a 50° maximum steering angle, D must be less than 0.57A.

Updated: 10.03.2014 — 04:02