DISPERSION MANAGEMENT IN SINGLE-MODE FIBERS

Анотація

Volkmar Brückner
Herder Foundation, Werl, Germany

Transfer of digital data packets in optical fibers is performed by propagation of digital signals at high bit rates. In reality Gaussian
shaped pulses of duration τB are used. Bit rate B relates to the bit sequence or time distance ΔtB between neighboring bits. For example,
a bit rate of B = 1 Gbps results in ΔtB = 1/B = 10-9 s = 1000 ps. In accordance with the recommendations of ITU-T a high-quality
transmission can be achieved only if the bit prolongation during propagation in the fiber is no more than ΔtB/10; it means in case of
1 Gbps transmission bit duration should be no longer than 100 ps. Note that at very high bit rates (B ≥ 1 Gbps) we find only Gaussian
shaped pulse in the fiber. In the following we will consider the reasons of pulse prolongation. We will present studies on the influence
of chromatic dispersion (CD) as well as polarization mode dispersion (PMD) to the bit rate and its influence on the maximum
transmission length in Standard Single-Mode Fibers (SSMF). Nature of CD and PMD is described elsewhere [1].