Good day,
I am trying to build a coherent optical system with carrier frequency offset . Ingnore the other components, the coherent system could be simplified to two lasers coupled.
When the center frequencies of two lasers are same, the outputs of coupler are normal(their sequences length are not change). But when I set a frequency offset between two lasers (the center frequency of the first laser is set to 193.1THz, and the second is set to 193.0999THz), the sequence lengths of the outputs of the coupler is doubled which is confused me. And there have half bits as the picture attached.
Is there someone know how to solve this problem ? Thanks in advance.
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