How to reduce sheath waves?

A sheath wave barrier (also called a sheath wave absorber or sheath current filter) attached to a coaxial line in or near the equipment can attenuate or prevent high-frequency sheath waves. In the simplest case, it is a ferrite core that contains inner and outer conductors in coaxial cables and acts as a current-compensated choke or common-mode choke. A ferrite core also functions as a transformer so that a useful signal can be maintained as a push-pull signal. The cable can also be passed through the core several times to increase inductance against unwanted common mode signal components.