The extinction ratio is an important parameter to consider when choosing cables for various applications. It is defined as the ratio of the transmitted power of a polarized beam through a polarizer placed in its path, when the polarizing axis is parallel to the beam’s plane, as compared to the power transmitted when the polarizer’s axis is perpendicular to the beam’s plane.
Cables used in telecommunications and other applications generally use multiple pairs of wires enclosed in a jacket. Each of these pairs of wires has a respective signal and ground, and they are often twisted together to reduce the effects of electromagnetic interference. The twist in the wires can be used to prevent cross-talk between adjacent pairs of wires, and therefore increase the signal integrity.
The twist in the wires also has an effect on the extinction ratio of the signal. As the signal passes through the cable, the polarizing axis of the signal can be altered. When the polarizing axis is changed, the signal is weakened, leading to a reduction in the power of the transmitted signal. This weakening of the signal is known as extinction, and the ratio of the transmitted power when the polarizing axis is parallel to that of when the polarizing axis is perpendicular is known as the extinction ratio.
The extinction ratio of a cable is a very important factor to consider when selecting a cable for a given application. Cables with a high extinction ratio will provide better signal integrity, and therefore are often preferred for applications that require higher data rates. In addition, cables with a high extinction ratio will also be more resistant to external interference, making them more suitable for applications that require a high degree of signal integrity.
In conclusion, the extinction ratio is an important parameter to consider when selecting cables for various applications.