A 2.488 Gbit/s optical link for a fast and reliable data readout and acquisition

We report on a digital optical transmission system with a data rate of 2.488 Gbit/s. A novel parallel coding and synchronization concept has been introduced which offers a 16-times reduced operating frequency for the concerned circuit parts. The performance of the chosen 3b4b-block coder is discussed by an evaluation of the frequency characteristics of the coded pulse train and a comparison to other standard coding concepts. A simple simulation model of the complete optical path enables the prediction of basic system characteristics in the time domain for a large range of operating parameters. The receiver provides the transmitted data to a user-defined bus or to the industrial VMEbus. Reliability studies have shown a systemʹs bit error rate below 10−13.