Pre-Equalization and Bandwidth Limitation for a 100-G-Baud 32 QAM All-Silicon Transmitter.

Pre-equalizer as high-pass digital filter compensates for transmitter (Tx) frequency response to improve high-baud rate transmission performances; however, it also increases the signal peak to average power ratio (PAPR) at the digital to analog converter (DAC). The increased PAPR induces performance penalty due to the reduced signal-to-noise-and-distortion-ratio (SINAD) at the DAC. It also reduces the Tx optical power due to the limited peak-to-peak amplitude of the DAC output. As a tradeoff between bandwidth compensation and the PAPR, the pre-equalization can be optimized for the best transmission performance. With the optimized pure digital pre-equalization, 100G Baud 16 QAM and 32 QAM transmission is performed with all-silicon photonics IQ modulator. We also investigate the limitations due to analog bandwidth. Simulations show that the Tx analog frequency response roll-off slope and the analog bandwidth below −15 dB are important for high-baud rate transmission with pre-equalization. [ABSTRACT FROM AUTHOR]