  In this paper, we investigate the collective synchronization of system of
coupled oscillators on Barab\'{a}si-Albert scale-free network. We propose an
approach of structural perturbations aiming at those nodes with maximal
betweenness. This method can markedly enhance the network synchronizability,
and is easy to be realized. The simulation results show that the eigenratio
will sharply decrease to its half when only 0.6% of those hub nodes are under
3-division processes when network size N=2000. In addition, the present study
also provides a theoretical evidence that the maximal betweenness plays a main
role in network synchronization.
