研究目的
To experimentally transmit a single channel 224 Gbit/s (56-GBaud) 16-level pulse amplitude modulation (PAM-16) signal over a 100 m standard single-mode fibre (SSMF) using intensity modulation and direct detection (IM/DD) with linear digital pre-distortion (DPD) to mitigate inter-symbol interference (ISI).
研究成果
The transmission of a 224 Gbit/s (56-GBaud) PAM-16 signal over a 100 m SSMF has been successfully achieved using linear DPD and an 8-bit DAC. This method mitigates the strong ISI caused by limited bandwidth, offering a viable approach for high-level PAM signal transmission at high baud rates, potentially applicable to the 400GE standard.
研究不足
The system's 3 dB bandwidth is around 22 GHz, which is far below the required bandwidth for the 56-GBaud PAM-16 signal, introducing severe inter-symbol interference (ISI). The linear DPD technique, while effective, adds complexity with the need for an additional finite impulse response (FIR) filter at the transmitter.