What must occur before digital modulation can take place in an optical transmitter?

In optical communication, digital modulation is the process by which digital data is converted into a signal that can be transmitted over fiber optic cables. Before this modulation can occur, the data must be properly prepared to ensure that the transmitted signal accurately represents the intended information.

Encoding the data is a crucial step because it transforms the raw digital information into a format suitable for transmission. This encoding can involve converting binary data into a specific modulation scheme that can be effectively transmitted as light signals. This ensures that the receiver can appropriately interpret the incoming light signals back into usable data.

By encoding the data beforehand, the optical transmitter is able to modulate the light signal in a way that matches the characteristics of the fiber optic medium, allowing for effective transmission over distance without loss of information integrity. Various encoding schemes can improve performance, reduce errors, and enhance the efficiency of data transmission, making this step fundamental to successful digital modulation in optical systems.