An Energy-Efficient FPGA-Based Real-Time IMDD OFDM-PON Enabled by an Efficient FFT

For the first time, a highly energy-efficient 32-parallel 64-point FFT scheme for IMDD OFDM-PON is proposed and implemented on a Xilinx ML605 platform. By experimentally verifying the power consumption model for the FPGA logic resources utilized in the FFT, the relationship between FFT calculating consumption and FPGA logic resource usage is established. Based on this relationship, we derive a resource selection principle for the FFT bit resolution optimization to minimize power consumption under different levels of received optical power. Consequently, the proposed FFT achieves a 76.1% reduction in power consumption compared to the traditional Spiral FFT at a received optical power of -21 dBm. Based on the proposed FFT, the real-time OFDM-PON receiver power consumption can save up to 43% compared with traditional OFDM-PON system.