A Variable Polarization Phased Array Antenna In Ku-band For "Satcom On The Move" System

With the rapid development of satellite communication technology, "satcom on the move" technology has been appliced more and more extensive and in-dept. The core part of the "satcom on the move" system is automatic tracking module. At present, the application of satellite automatic tracking module uses a mechanical servo system to perform automatic tracking function, the accuracy and speed of angle and polarization tracking are not efficient.This paper focuses on the polarization and angle tracking accuracy issues, design and producted a variable polarization phased array antenna in Ku-band. The antenna unit adopts the form of microstrip antenna. It can radiate dual circular polarized wave, which can synthetize linear polarized wave in any direction. The antenna array using subarray arranged to form an array of concentric rings, effectively increasing the accuracy and speed performance tracking in polarization tracking through the "satcom on the move" system.To begin with, microstrip antenna element is designed on the basis of the theory of polarization synthesis in this paper. A variable polarization phased array antenna was designed by phase controlled double circular polarized wave antenna unit radiation, which implements the polarization tracking phase control. The array was designed on the basis of phased array theory, which transits from 1×8 linear array to 8×8 planar array and realizes the two dimensional range of ±45°phased beam scanning function. To meet the needs of high precision pointing beam, high gain and low sidelobe, the entire array plane was designed combined with practical application conditions. And the concentric ring array is composed of 15 antenna subarrays with rotating configuration( 8×8 planar array) in this design. Product process and the measurement resule of unit and subarray antenna given. Simulation results show good agreement with the measurement results. The antenna can satisfy the needs of practical engineering well. It solved the theoretical and engineering problem of polarization and angle tracking accuracy in "satcom on the move" system.