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The Optical Network Emulation (ONE) engine is a real-time, multi-container software platform designed to model and emulate open optical transport networks with realistic fidelity. This paper introduces an enhanced version of the ONE engine that integrates a distributed implementation of a Gaussian Noise (GN) model for estimating nonlinear interference (NLI) in wavelength division multiplexing (WDM) systems. The inclusion of the GN model enables more realistic emulation of nonlinear signal degradation across diverse link configurations and operating conditions. The enhanced ONE package is then used to document the model’s impact on system performance under varying transmission conditions, including signal launched power and increased spectral loading. With this upgrade, the ONE engine expands its utility for research, development, and education, providing a scalable and flexible environment for testing physical-layer impairments and control strategies in software-defined optical networks. 

We present a novel measurement technique for P-OFDR with a digitally created linear chirp in the transmitter and vector complex optical field detection to measure the Stokes parameters along the fiber. 

A high resolution FMCW Lidar system based on a phase-diverse self-homodyne coherent receiver is demonstrated. Using the same linearly chirped waveform for both the transmitted lidar signal and the local oscillator, the self-homodyne coherent receiver performs frequency de-chirping in the photodiodes which significantly simplifies the task of signal processing, and the required receiver bandwidth can be much lower than the signal chirping bandwidth. While only amplitude modulation is required in the lidar transmitter, phase-diverse coherent receiver allows simultaneous detection of target range and velocity through the spectrum of the de-chirped complex waveform. Multi-target detection is also demonstrated experimentally. 

Performance of distributed Raman amplification (DRA) system with dual order forward (FW) pumping is analyzed with the consideration of both pump relative intensity noise (RIN) to signal phase noise transfer and signal nonlinear interference. The efficiencies of pump RIN to signal phase noise transfer are theoretically analyzed and experimentally verified by measuring signal phase noise introduced by small index intensity modulations applied on the pump lasers. The results indicate that the efficiency of 2nd order pump RIN to signal phase noise transfer can be more than 2 orders of magnitude higher than that from the 1st order pump. Although dual order FW Raman pumping corresponds to a slight increase of amplified spontaneous emission (ASE) compared to using only a 1st order pump, its major advantage comes from the reduction of nonlinear interference noise in a dense wavelength-division multiplexing (DWDM) system. Because pump RIN to signal phase noise transfer has lowpass characteristics, systems at high baud rates, such as 100 Gbaud, are less susceptible to the impact of pump laser RIN. 

We demonstrate 20-channel coherent transmission using a high-power single-section QW FP-laser diode over 78.3 km single mode fiber. The system capability can reach > 4Tb/s with a single laser in the transmitter using polarizations multiplexing. 

Electrostriction in an optical fiber is introduced by interaction between the forward propagated optical signal and the acoustic standing waves in the radial direction resonating between the center of the core and the cladding circumference of the fiber. The response of electrostriction is dependent on fiber parameters, especially the mode field radius. We demonstrated a novel technique that can be used to characterize fiber properties by means of measuring their electrostriction response under intensity modulation. As the spectral envelope of electrostriction-induced propagation loss is anti-symmetrical, the signal to noise ratio can be significantly increased by subtracting the measured spectrum from its complex conjugate. We show that if the transversal field distribution of the fiber propagation mode is Gaussian, the envelope of the electrostriction-induced loss spectrum closely follows a Maxwellian distribution whose shape can be specified by a single parameter determined by the mode field radius. 

We present a simple technique for in-field determination of fiber types through the measurement of electrostriction effect based on self-phase modulation 

We demonstrate a novel technique to measure the nonlinear phase shifts of multi-span fiber optic links with a polarization-multiplexed coherent transceiver based on cross-phase modulation between two orthogonally polarized subcarrier tones.