The curtain array was usually composed of folded dipoles as elements for their high input impedance, but its bandwidth had a limitation for its antenna mode. This paper proposed a method for broadband folded dipoles using branch arms for current redistribution, which increased the bandwidth of input impedance and VSWR effectively by choosing the proper positions of the branch wires. The current distribution on branch model showed an unbalanced condition as the branch wires moved. As verification, a practical model with cage antenna had been analyzed by the present method and FEKO. The results illustrated that when factor k was between 0.4 and 0.5, the bandwidth would be maximum.