Tuesday, May 1, 2012
Special Seminar in Applied Mathematics
Microstrip Reflectarrays for Large-Aperture Interferometric Radars
Sembiam Rengarajan, CSU Northridge/JPL
Microstrip reflectarray antennas have been investigated for numerous ground and space applications because of their desirable characteristics such as low profile, and ease of design, manufacture, and deployment. Reflectarrays employ printed elements of variable size, stub length, or orientation to collimate the radiation along the direction of interest. Future space based remote sensing instruments will require ever increasing antenna aperture sizes. The large aperture size of reflectarrays severely limits their operating frequency bandwidth because of the modulo 2Π phase shift produced by each element at the design frequency for beam collimation. Piecewise planar parabolic (PPP) reflectarrays obviate this bandwidth limitation. In this talk we will describe the theory and properties of microstrip reflectarrays. Recent developments in reflectarrays presented in the current literature will be reviewed. Design and analysis of fully planar and PPP reflectarrays employing rectangular patch elements for dual-polarization dual-beam applications will be presented. Determination of the reflection phase of the infinite array of microstrip patch elements, illuminated by a plane wave will also be discussed.