Abstract
In this paper, a quadrafilar antenna is designed to have a lower profile as an essential part of the size reduction technique and lower backradiation(namely, higher forward radiation) for the S-band telemetry/telecommand(TM/TC) function of a communication satellite. Particularly, to meet the challenging requirements on the higher isolation between the TM/TC antennas and simultaneously a smaller size, the lowest backradiation and lowest cross-polarization, the optimal physical dimensions of the quadrafilar antenna are found by using the Genetic Algorithm(GA). To prove the validity of the proposed antenna design, its 3D electromagnetic analysis and measured results are compared to show good agreement. Using this antenna as the elements, an array antenna is made to have directivity.
