The optical signal parameters defining the signal level include optical transmitter output power, extinction ratio, optical amplification gain, and photodiode responsivity. The optical transmission system has to be properly designed to provide reliable operation during its lifetime, which includes the management of key engineering parameters. Understanding their key parameters isn't just technical jargon – it's critical for ensuring compatibility, performance, and reliability in your data center. We have discussed the properties of optical sources. The source drive circuit intensity modulates the opt cal source by varying the current through the source. Typically, the detector is characterized by a level of sensitivity to impinging optical power.