AN649

FIBER OPTIC CIRCUITS Application Note 649: Jun 28, 2000 HFTA-04.0: Optical/Electrical Conversion in SDH/SONET Fiber Optic Systems This article explains the basic functions and design challenges of the optical to electrical and electrical to optical signal conversion in SDH/SONET fiber optic receivers and transmitters. A complete chip set solution to develop the electronic part of OC 12/STM 4 receivers and transmitters is presented. The advent of cheaper and more powerful personal computers has not only expanded the user base; it is also creating a demand for greater transmission capacity among the telecom networks by adding an increasing volume of internet and videophone connections to the traditional phone and fax services. The following discussion of an OC 12/STM 4 receiver/transmitter chipset supports these developments and includes a description of the electronic components required for optic/electric (O/E) conversion in SDH/SONET fiber optic transmission systems. Competition among network providers enables the multimedia market to grow, and the introduction of new and improved products and services in the near future should strengthen the demand for increased transmission capacity. This need for more data throughput can be satisfied economically with fiber optic (FO) cables because the transmission capacity is potentially very high (versus that of copper wires). The physical nature of the fiber cable lets providers expand capacity by increasing the transmission bit ra...