A Baseband Receiver for Optical OFDM Systems

Orthogonal frequency division multiplexing (OFDM) technique has been widely adopted in wireless communication systems. However, the study of OFDM technique for optical transmission system is still emerging in the research field. In this paper, we propose a baseband receiver architecture for the optical OFDM system. The baseband receiver contains frame detection, carrier frequency offset (CFO) estimation and compensation, channel estimation, and equalization. This paper also proposes a fast Fourier transform (FFT) processor with highly parallel architecture for the high-throughput requirement in the optical system. Finally, the FFT processor is designed and implemented using 90nm UMC CMOS technology. The measurement result shows that this chip achieves 2.67GS/s throughput for the optical OFDM system.