How far can the IDM-Video Phone video telephone optical multiplexer transmit?

The transmission distance of a video telephone optical multiplexer depends on the margin between three factors: the transmit optical power, the receiver sensitivity and the line loss. The IDM-Video Phone video telephone optical multiplexer comes standard with 20 km single-mode transmission, corresponding to a 155M optical interface, a transmit optical power of -15 to -8 dBm and a receiver sensitivity better than -32 dBm; the available optical power margin left between the two ends is the margin part of the link budget, and the actual reachable distance must also be calculated in conjunction with the optical cable loss, the number of fiber adapters and splice points, and the termination quality. When a longer distance is required, a long-distance optical module can be optionally installed, or video lossless regenerative repeaters can be used to regenerate a long link in segments, and the video quality does not degrade because of the regeneration; in engineering practice it is recommended to leave a certain optical power margin at both ends of the link.