A study of array pattern tuning method using hybrid genetic algorithms for figure-8 satellite's earth station antenna

An array pattern tuning method of the fixed earth station's antenna for figure-8 satellite was described. The conditions of the array antenna's design are to track the figure-8 satellite and direct nulls to multiple geostationary satellites in order to share the same frequency between figure-8 satellite and geostationary satellites. To determine optimal excitation coefficients of the array antenna, Hybrid Genetic Algorithms (Hybrid GA) which is the combination of Genetic Algorithm (GA) and descent method were applied. Simulations were performed for the phased array antenna, which had 4 by 4 element antennas and 4-bit phase shifters. For 9 of 11 directions of figure-8 satellite, hybrid GA found the designed antenna pattern.