Research and Implementation of the Key DSP Algorithm in the O-OFDM System

This paper focuses on the design of core digital signal processing (DSP) algorithms for optical orthogonal frequency division multiplexing (O-OFDM) systems, specifically digital baseband receivers. The two most critical DSP techniques, synchronization and channel estimation, are discussed. Symbol synchronization and sampling frequency synchronization are two synchronization techniques that are crucial for proper system function. Deviations in symbol synchronization timing points can lead to inter-symbol interference (ISI) and inter-channel interference (ICI), while sampling frequency offset (SFO) can cause amplitude attenuation, phase rotation, and ICI interference of OFDM symbols in the frequency domain. Following comprehensive simulation verification, the optimized DSP algorithm proposed in this paper has been demonstrated to reduce the complexity of FPGA implementation, improve the operational speed of the system, and provide robust support for achieving high-speed O-OFDM systems.