If a four-port network is terminated by arbitrary impedances, conventional
methods for even- and/or odd- mode excitation analyses cannot be used becau
se no symmetry planes exist. Under these conditions, new design equations f
or an asymmetric branch-line hybrid with arbitrary power division are intro
duced. A uniplanar branch-line hybrid terminated by 45, 35, 60 and 50 Ohm w
ith a power splitting ratio of 3dB was fabricated and measured.