Experimental Study on Economic Long-haul Transmission Link Using standard SMF and All EDFAs

We systematically compare the transmission performance of three different modulation formats, return-to-zero (RZ), chirped RZ (CRZ) and vestigial sideband RZ (VSRZ) on the economically effective transmission link using standard single mode fiber (SSMF) and all Erbium-doped fiber amplifiers (EDFAs). This link is composed of wavelength division multiplexed (WDM) channels at 10 Gbit/s over 24 times 100 km amplifier spans without using new types of fibers and Raman amplifiers. The generation of each modulation format in experiments is optimized for more reasonable comparison, and their optical characteristics are investigated by comparing with simulation results. Optimum input powers into SSMF and dispersion compensation fiber (DCF) for each modulation format signal were explored and transmission performance was compared. In our cost-effective transmission link, CRZ signal showed the lowest input power and best performance among all the formats investigated.