Optical amplifiers are best suited for shorter transmission distances between the transmitter and receiver. An optical repeater receives the optical signal and converts it into an electrical signal. As the amplified, distorted signal continues its journey, the noise component also gets further distorted, potentially compounding. At their core, both optical fibre amplifier and repeaters have a similar goal: boosting the signal so that it can travel farther. However, the way they achieve this is radically different. Imagine a light signal traveling through miles of fiber optic cables. There are two basic approaches. Such repeaters are used to extend the reach of optical communications links by overcoming loss due to attenuation of the optical fiber.
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