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Applicability of Gaussian Noise Approximation for Optically Pre-Amplified DPSK Receivers with Balanced Detection

Xiupu Zhang·Zhenqian Qu·Guodong Zhang·Guangxue Yang
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Abstract

This letter presents a comparison of exact probability density function with the Gaussian noise approximation in optically pre-amplified DPSK receivers with optical Mach-Zehnder interferometer demodulation (MZI) and balanced detection, including the impact of phase noise. It is found that the Gaussian noise approximation significantly over-estimates ASE-ASE beat noise in DPSK receivers with balanced detection particularly when phase noise is negligible, compared to IM/DD receivers, ASE- amplified spontaneous emission. However, the Gaussian noise approximation is still applicable for DPSK receivers with balanced detection and the measured 3-dB advantage is predicted by the Gaussian noise distribution.

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Xiupu Zhang, Zhenqian Qu, Guodong Zhang, Guangxue Yang. 2004-10-19. Applicability of Gaussian Noise Approximation for Optically Pre-Amplified DPSK Receivers with Balanced Detection. https://arxiv.org/abs/physics/0410029

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