A microwave antenna assembly is disclosed. The antenna assembly includes afeedline having an inner conductor,,an outer conductor and an inner insulator disposed therebetween. A radiatingportion is also included having an unbalanced dipoleantenna including a proximal portion and a distal portion that are ofdifferent lengths. The proximal portion includes at least a portionof the inner conductor and the inner insulator and the distal portion includesa conductive member.