Reduction of stimulated Brillouin backscattering (SBS) in optical transmission systems

摘要

The invention reduces stimulated Brillouin backscattering (SBS) in optical transmission systems by broadening the frequency spectrum of transmitted signals. In particular, the invention utilises the non-linear effects of self phase modulation (SPM) or cross-phase modulation (XPM) to counteract Brillouin scattering. Figure 1 shows an optical transmission link having a terminal TT, fibre LWF, amplifier AMP and receiving terminal TR. A plurality of laser-modulator devices LM1-LMn receive binary data signals DS1-DSn which modulate carrier signals of different wavelength. To further reduce the effects of Brillouin scattering, a plurality of amplitude modulated (AM) pump signals from sources PL1 -PLm may be fed into the fibre.