It is worth mentioning that the characteristic impedance of a twisted pair is closely related to its pitch, which is why each standard defines the pitch of a twisted pair.
Coaxial cable (Coaxial Cable) is sometimes referred to as RF cable (RF Cable), coaxial RF cable is the most commonly used structural type. Because the inner and outer conductors are in concentric positions, the electromagnetic energy is limited to propagate in the medium between the inner and outer conductors, so it has significant advantages such as small attenuation, high shielding performance, wide operating frequency bandwidth and stable performance.