Fiber-Optic Cable Signal Loss, Attenuation, And Dispersion - Juniper ACX6160 Hardware Manual

Figure 15 on page 38 shows an LC duplex connector being installed in a transceiver.
Figure 15: LC Duplex Connector

Fiber-Optic Cable Signal Loss, Attenuation, and Dispersion

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Signal Loss in Multimode and Single-Mode Fiber-Optic Cable | 38
Attenuation and Dispersion in Fiber-Optic Cable | 39
Signal Loss in Multimode and Single-Mode Fiber-Optic Cable
Multimode fiber is large enough in diameter to allow rays of light to reflect internally (bounce off the
walls of the fiber). Interfaces with multimode optics typically use LEDs as light sources. However, LEDs
are not coherent sources. They spray varying wavelengths of light into the multimode fiber, which
reflects the light at different angles. Light rays travel in jagged lines through a multimode fiber, causing
signal dispersion. When light traveling in the fiber core radiates into the fiber cladding, higher-order
mode loss results. Together these factors limit the transmission distance of multimode fiber compared
with single-mode fiber.
Single-mode fiber is so small in diameter that rays of light can reflect internally through one layer only.
Interfaces with single-mode optics use lasers as light sources. Lasers generate a single wavelength of
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