A compact planar ultra-broadband sum-and-difference network
一种小型超宽带平面和差网络

In this paper, a novel power divider is proposed. Based on this power divider, a planar ultra-broadband microstrip sum-and-difference network is designed. This network employs the novel power divider and anti-phase balun as a building block. An equivalent 180o coupler is achieved by back-connecting the power divider and balun together. Four such couplers are connected to form the ultra-broadband sum-and-difference network. The features of this network are verified to be excellent, resulting in the advantages of being compact, easy manufacturing and low cost.