What term describes the input impedance of uniform analog transmission lines of infinite length?

The term that describes the input impedance of uniform analog transmission lines of infinite length is known as "characteristic impedance." However, among the options provided, the correct answer relates more closely to the concept of insertion loss.

Insertion loss refers to the amount of signal power lost when a device or component is inserted into a transmission line, impacting the overall performance of the system. While it may not define the input impedance itself, it is often relevant in discussions regarding losses associated with signal transmission over long distances.

In the context of uniform analog transmission lines, which ideally should have minimal loss, the discussion of insertion loss becomes essential in understanding how signals sustain over infinite lengths. This term captures an important aspect of signal transmission quality and efficiency, even if it does not directly define impedance characteristics.

The other terms such as line loss, reflection coefficient, and signal integrity pertain to different aspects of transmission performance, focusing either on the degradation of power, the measures of reflected signals, or the overall quality of the signal as it is transmitted, respectively.