RACE project 2012 HIPOS 40 Gbit/s OTDM transmission systems with optical demultiplexers

This paper pays particular attention to the 40 Gbit/s test bed developed to assess the performance of the polymer demultiplexer. In addition to the basic performance of the testbed, the requirement of satisfactory performance for all transmitted channels, rather than just a single channel, and the start-up difficulties involved in demodulating this signal down to the base rate (for example 10 Gbit/s) are discussed. Transmission of a single polarisation 'true' 40 Gbit/s OTDM data stream over 205 km using a stabilised 10 GHz erbium fibre ring laser and four independently driven lithium niobate modulators to generate the signal, and a 40 GHz electronic clock recovery circuit to drive the lithium niobate demultiplexer array with 10 GHz sine waves, is demonstrated. An outline of the remainder of the project is given, including materials and fabrication issues.