A modulation format is necessary to suit the information to a form that can be transmitted over an optical fibre. In addition, achieving high bit rates and significant information capacities of transmission systems is associated with the use of appropriate modulation formats. Every modulation performs in a different way and is suitable for different transmission scenario. For this reason, it is necessary to familiarize students with principles of advanced modulation formats, which are part of any optimization processes within modern high-speed optical transmission networks.
The goal of this teaching material is to present the overview of digital modulation formats, including amplitude, phase, a multilevel or advances formats combining more parameters. The description includes principle of particular modulations, their benefits and certain disadvantages. A reader should be able to consider which modulation format is suitable for a given application area (in terms of suitable fibre lengths, information capacity, spacing between frequency channels, among others).
Modulation, intensity modulation, phase modulation, multistage modulation, multicarrier modulation, polarization multiplexing, on-off keying, return to zero, non-return to zero, duobinary modulation, carrier suppressed return to zero, BPSK, DPSK, QPSK, PM-QPSK, OFDM, VDMT.