2x8 QPSK Mixer
To be used for optical coherent detection such as DP-QPSK receivers, Optoplex’s ten-port 2x8 Coherent Mixer (aka QPSK mixer) combines the incoming signal with a local oscillator to generate eight light states in the complex-field space. The eight light output signals can then be coupled into four pairs of balanced detectors. The block diagram below shows the application of a 2x8 coherent mixer in a DP-QPSK receiver. Since the mixing process is data rate independent, the devices can be used for any data rate in applications such as 40Gb/s or 100Gb/s transmission systems.