Crosstalk reduction for compact optical transceiver module

We propose crosstalk reduction for the compact optical transceiver module. Crosstalk is composed of three elements: crosstalk resulting from electromagnetic coupling between adjacent signal lines, crosstalk resulting from electromagnetic coupling between transmission and reception, and crosstalk resulting from source impedance. Each element was reduced by adding a shield pattern and reducing the impedance of the pattern and that of the source pattern. We fabricated a module and demonstrated error-free transmission with simultaneous operation at 25 Gb/s by using a 2³¹-1 pseudo random bit stream (PRBS).