摘要 |
<p>The invention relates to an optical unit (17) for synchronizing clock signals. The unit (17) comprises at least two ring lasers (1', 1''), each ring laser (1', 1'') generating a repetitive optical pattern at a different repetition frequency fi. The repetition frequency of at least one of the ring lasers (1', 1'') is variable. The unit (17) comprises detection means (19) adapted to simultaneously receive the optical patterns from two ring lasers (1', 1'') to be synchronized with each other and to compare these patterns. The ring laser, whose repetition frequency is variable, is controllable on the basis of a signal from the detection means, by which the optical path length of this laser is changed. The invention also relates to a high-frequency carrier transmission system comprising an optical unit as described hereinbefore.</p> |