6 - Unrepeatered transmission

Abstract

Unrepeatered submarine systems, also called repeateriess systems, are described in this chapter. Unrepeatered systems do not involve in-line repeaters, therefore they do not require electrical power feeding of the cable nor submerged electrically active components. Because of the absence of periodical optical amplification, unrepeatered systems are mainly loss-limited systems, which means achievable spans can be derived most often from cable loss. Typical covered distances are of a few hundred kilometers and may vary significantly depending on the capacity to be transmitted. In addition, submarine fiber optic systems are used to create telecommunication backbones with very high capacities per cable. These networks consist of a combination of long-distance repeatered systems and of shorter distance unrepeatered systems. Unrepeatered systems do not involve in-line repeaters; therefore they do not require electrical power feeding of the cable nor submerged electrically active components. Because of the absence of periodical optical amplification, unrepeatered systems are mainly loss-limited systems, which means achievable spans can be derived most often from cable loss. This chapter also describes network applications and system configurations followed by available system technologies. Usually, unrepeatered systems work at the edge of the optical power limitation induced by nonlinear effects… Typical covered distances are of a few hundred kilometers and may vary significantly depending on the capacity to be transmitted.