Broad-Band Twisted-Wire Quadrature Hybrids (Short Papers)

A symmetrical 3-dB quadrature hybrid, consisting chiefly of a bifilar pair of twisted wires, is described. A cascade of two such hybrids can achieve an octave bandwidth with a 0.7-dB coupling error. Since this class of hybrid is simple, compact, and low in cost, its use may be preferred over the more common coaxial line or printed-circuit types in the frequency region below 1 GHz.