A four-port, aperture-coupled, unequal power divider is presented. The power ratio modification is fulfilled by the utilization of the defected ground structure (DGS). Effects of the changing defect length on the power distribution are presented. The power efficiency examination is also carried out. The simulation results show that at 10 GHz, the proposed device can supply varying port powers with a reflection loss better than 22 dB. © 2010 IEEE.