What defines a baseband signal?

Passband signal

What's the difference between the spectrum of a real-valued and a complex-valued passband signal?

which information does the carrier of a signal with modulation index m<1 carry?

what are the reasons to choose a particular modulation format?

RZ vs. NRZ

pros and cons of PSK

Why use gray coding for multi-level signals?

optimum constellation diagram

what is a constellation diagram?

two most common modulators in optical communication

difference between EAM and laser diode?

principle of MZI

two typical operation modes of MZI

name two operation points of a MZI

name the device needed to modulate the amplitude and phase of a carrier

advantage of a software-defined transmitter

why is integrated parallel scheme for QAM modulation outperforming other schemes (tandem, cascaded)?