Impact of Component Crosstalk on Power Penalty of a WDM Receiver in QPSK Multiuser Optical Network

The Following study quantifies the performance deterioration of a wavelength division multiplexed (WDM) receiver due to the impact of component crosstalk while receiving a signal with QPSK (quadrature phase shift keying) modulation. The degradation in system characteristics is quantified by analyzing the BER (bit error rate) and PP (power penalty) across varying levels of crosstalk and different numbers of interfering channels. Utilizing a theoretical framework, the BER is approximated as a function of signal-to-noise ratio (SNR), crosstalk level, and the number of interferers. The results demonstrate that crosstalk significantly influences BER, particularly at medium to high SNR values. For a target BER of 10–⁹, a considerable increase in power penalty is observed with rising crosstalk levels and interfering channels. Detailed analysis using the derived expressions shows that maintaining high-quality transmission (QoT) necessitates increased SNR in the presence of crosstalk. Extensive datasets and graphical representations substantiate the findings. These provide critical insights for network administrators and system designers to optimize power allocation and enhance transmission quality in optical networks affected by component crosstalk. This work offers a comprehensive reference for mitigating crosstalk-induced impairments in QPSK-modulated systems.