A Study of Log Periodic Feeds Multiple-Beam Antenna: Offset Parabolic Reflector Antenna

Abstract

The application of an array of circular polarized log periodic dipole antennas (LPDA) as feed array for a multiplebeam antenna to cover 3.5:1 bandwidths is described. Meanwhile, the use of an array of log-periodic antennas for two kinds of arrangement: rectangular grid and hexagonal grid illumination is also presented. In comparison with the rectangular grid, hexagonal grid is more efficient in beam coverage area for synchronous-orbiting communications satellites. Enhanced feed concept is used in the LPDA feed array in order to increase gain in coverage area. Finally, the simulated results for beam contour which is excite by right-hand circular polarized LPDA of both grids and enhanced beam contour over the frequency range of 0.8GH to 2.5GHz are demonstrated.

The Research of the Plane Receiving Array in Offset Parabolic Reflector Antenna with Multi-Beam at Millimeter-Wave Band

“…The diffraction speckle of the incident beam with various angles in the main polarization field on the receiving plane is calculated and analyzed. The corresponding plane receiver array is chose and arranged, according to the characteristics (such as shape and size) of the diffraction speckles on the receiving plane [4][5][6][7].…”

Multi-Beam Antenna with enhanced Wavelength-Scaled Log Periodic Dipole Array feeds

“…LPDA is selected as our feed. At the end of [5], the author used enhanced LPDA feeds to improve the antenna's performance. Usually the diameter of LPDA element is larger than half wavelength in low frequency.…”