| 摘要 |
In an analog, fiber-based signal distribution system, a periodic electrical signal is frequency-multiplied by a factor of N, is converted to an optical signal, is optically amplified, is split among one or more optical fibers, is delivered by fiber to one or more remote units, is converted back to an electrical signal, is frequency-divided by the factor of N back to its original frequency, and can be used to generate synchronized clock signals at the remote units. The optical amplifier imparts a phase noise that is relatively independent of frequency, so that the phase noise contribution from the optical amplifier is advantageously decreased when the frequency divider reduces the frequency of the electrical signal. Compared to a distribution system that does not increase, then decrease, the frequency by a factor of N, the phase noise contribution from the optical amplifier is reduced by 20 log 10(N). |
