Global Loss Budget and Net Loss Budget of Optical Digital Transmission Systems

A comparison between global and net loss budgets of optical fiber digital systems is made, taking into account system margin and repair methods. The evaluation was made as a function of splice losses for 0.85 and 1.3 micron laser and LED systems, respectively, at 2, 8, 34, and 140 Mbit/sec, with a link bandwidth exceeding 100 MHz. With LED and laser diodes emitting 1 and 2 mW, respectively, for transmission, one repair/km was considered and performance of the two diodes was found to be comparable, although the laser produced better results with poor splicing. The evolution of splice losses for 10 and 25 km steps was projected, and ranges of tolerance to splice losses and the possibilities for actual use are provided.