| 摘要 |
<p>Methods and apparatus are provided for reducing Raman crosstalk in a wavelength-division-multiplexing(WDM) optical fiber transmission system (10) that transmits a multiplex of channels.Idle data is sent over one or more of the channels of the WDM system in order to maintainthe optical link (30) when user data is not being sent. The idle data has an idledata pattern, which can be controlled such that a power spectral density of a signalcarried by at least one channel is shifted in order to reduce Raman crosstalk betweenthe channels. For example, the power spectral density may be shifted away fromlower frequencies of the channel, and toward the higher frequencies, by controllingthe idle data pattern. Alternatively, the power spectral density may be shiftedtowards unused frequencies of the channel, by controlling the idle data pattern.</p> |
