Abstract: A phased-array antenna has been proposed with adopting virtual phase shifting technology to achieve the narrow main beam width and high-precision scan step required for terrestrial-satellite communication. Through algorithm weighted to the output of the array unit, adopting the limited bit phase shifter permutations in different algorithm, the antenna main beam width can meet actual demands. Based on the comparisons between different weights algorithm, the distribution of the phase shifters has been adjusted to meet the demanded half beam width scan accuracy. Simulation results show that the design and the algorithm are effective.