Introduction and general concepts; attenuation, dispersion, polalization effects, scattering effects, nonlinear effects, optical modulators (generalities, electro-optic modulators, electroabsorption modulators and acousto-optic modulators), optical amplification (basic concepts, saturation and noise effects, erbium-doped fibre amplifier, Raman optical fibre amblifier); coherent detection (digital modulation format, coherent detection schemes, demodulation schemes, signal degradation and solutions); system design (bitrate versus dispersion, power budget, BER curves, sources of power penalty); channel multiplexing (TDM, PDM, WDM and OFDM).