Eye‐Opening Factor as a Unifying Signal‐Quality Metric for 32‐Channel DWDM Systems: A Comparative NRZ/RZ Study Over 80–320 km

ABSTRACT The rapid expansion of data‐intensive applications including 5G networks, cloud computing, and high‐definition video streaming has driven an urgent need for high‐capacity and spectrally efficient optical communication infrastructures. This paper presents a comprehensive simulation‐based performance analysis of a 32‐channel dense wavelength division multiplexing (DWDM) optical communication system using OptiSystem software. Five important performance parameters are evaluated such as bit error rate (BER), Q‐factor, eye‐opening factor (EOF), optical signal‐to‐noise ratio (OSNR), and spectral efficiency (SE). The EOF is introduced as a novel normalized signal quality factor in this work. Non‐return‐to‐zero (NRZ) and return‐to‐zero (RZ) modulation formats are compared across transmission distances of 80–320 km and channel counts of 8, 16, and 32 at 10 Gbps per channel, with Erbium‐doped fiber amplifier (EDFA) amplification at each 80‐km span. RZ modulation achieves a peak Q‐factor of 18.7 dB, OSNR of 41.5 dB, and EOF of 0.95 at 80 km. SE analysis shows 0.1 bits/s/Hz is achieved at 100‐GHz channel spacing with a data rate of 320 Gbps using 32 channels. All Q‐factor values reported in this paper are expressed in dB scale consistent with the BER‐Q relationship .