Ultra-wideband Optical Receiver Using Electrical Spectrum Decomposition Technique

We propose an electrical spectrum decomposition technique using an ultra-broadband electrical bandwidth divider consisting of newly developed AMUX-based frequency shifters and an adder-subtractor based on in-house InP-HBT technology. Ultra-wideband optical $2\times 56$ -GBaud QPSK signal was successfully received and decomposed into narrowband signals.