Real-time 15GBaud QPSK and 16QAM Flexible Coherent Optical Receiver Implemented on a Single FPGA Chip with Low Complexity DSP

We demonstrate real-time flexible coherent optical receiver based on a single FPGA chip, which uses a set of digital signal processing (DSP) algorithms with low complexity to realize the processing of 15GBaud single-polarization QPSK and 16QAM signals under the control of computer. We compare its hardware resources consumption with those FPGA implementations that use the same DSP algorithm but only enable DSP for single modulation format (QPSK or 16QAM), and find that the former has no significant increase in most resources. A real-time back-to-back experiment under different received optical power (ROP) is carried out to demonstrate the bit error rate (BER) performance of the FPGA-based QPSK&16QAM receiver.