Characteristic Impedance

This is the input impedance when a transmission line or electronic component is regarded as a transmission line, and is determined by the current value generated against the input voltage in a high frequency signal (voltage value/current value).
When two or more parts or transmission lines are combined, if the value differs between adjacent parts, a phenomenon called "signal reflection" occurs, causing signals to flow in the opposite direction to the intended direction. It becomes "noise" by putting it away and interferes with healthy signal transmission.
Reflection also occurs when this value changes due to the complexity of the structure inside the connector. Stabilizing the "characteristic impedance" while having a complex structure that satisfies the mechanism is an important point for connectors for high-speed transmission.