Summary form only given. In this three-wave process, the incident light is converted into Stokes light of longer wavelength due to the Doppler shift associated with the acoustic wave. SBS causes the degradation in optical signals, and thus sets a limitation on system performance. For the systems of high-power transmitters and long spans, this effect becomes an important factor in the system design. It is known that the SBS threshold is determined by the Brillouin gain spectrum. Therefore, the SBS thresholds for different types of fibers can be derived by measuring their Brillouin gain spectra. The Brillouin optical-time-domain reflectometer (BOTDR) based on heterodyne detection has been used to measure the spontaneous Brillouin scattering spectra along the fiber length. The SBS gain spectra for fibers can be derived from the spectra of spontaneous Brillouin scattering, and thus the SBS thresholds of fibers can also be obtained. We propose a method to measure the SBS thresholds for various types of single-mode fibers by utilizing BOTDR. The SBS threshold measurement with BOTDR method for a standard single-mode fiber (SMF), large-effective-area dispersion-shifted fiber (LEAF), truewave/reduced slope fiber (TWF) and conventional dispersion-shifted fiber (DSF) have also been demonstrated and analyzed.
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