Showing papers on "Dispersion-shifted fiber published in 2020"

Study on the simultaneous distributed measurement of temperature and strain based on Brillouin scattering in dispersion-shifted fiber

Abstract: Utilizing the large effective area non-zero dispersion-shifted fiber (LEAF), a multi-parameter optical-fiber sensor has been proposed and experimentally demonstrated for distributed simultaneous temperature and strain measurement, which is based on multiple acoustic modes in spontaneous Brillouin scattering (SpBS) effect. Proof-of-concept experiments demonstrate 3 m spatial resolution over 2.5 km sensing LEAF with 2°C temperature accuracy and 60µɛ strain accuracy. The proposed distributed Brillouin optical fiber sensor allows simultaneously temperature and strain measurement, thus opening a door for practical application such as superconducting cable.

A mitigation of channel crosstalk effect in dispersion shifted fiber based on durability of modulation technique

Abstract: In fiber optics the Four Wave Mixing (FWM) has the harmful effect of an optical transmission system that can severely limit Wavelength Division Multiplexing (WDM) and reduce the transmission aptness. This work preset the durability of the different modulation format was tested to FWM by using Dispersion Shifted Fiber (DSF). Moreover, the performance of the proposed system is surveyed by changing the fiber length and applying an information rate of 200 Gb/s. The experimental results show that the FWM capacity has decreased significantly by more than 14 dB when applying Return to Zero (RZ) modulation form. In addition, in terms of the propsed system performance in the first channel and with 700 km distance, it was observed that the lower Bit Error Rate (BER) in the normal RZ modulation is equal to 1.3×10-13. As well as it is noticeable when applied the Non Return to Zero (NRZ), the Modified Duobinary Return to Zero (MDRZ) and Gaussian modulation, the system performance will be quickly changed and getting worse, where the BERs increased to 1.3×10-4, 1.3×10-6 and 1.3×10-2 consecutively at same channel and for the same parameters.

Achievable Mitigation of Nonlinear Phase Noise through Optimized Blind Carrier Phase Recovery

Abstract: Partial mitigation of nonlinear phase noise by standard carrier phase recovery has been reported both, experimentally and through simulations. In this paper we quantify the achievable mitigation by using different implementations of the carrier phase recovery. All the approaches are based on the widespread blind phase search algorithm but follow different optimization strategies for handling simultaneously both, linear and nonlinear impairments of the channel. We apply the algorithms on probabilistically shaped signals transmitted over standard single mode fiber and non-zero dispersion shifted fiber in order to consider conditions in which the system performance is evidently affected by nonlinear phase noise. The results obtained are finally compared to the statistically estimated achievable phase noise removal. This allows to evaluate in different system scenarios an upper bound to the potential gain obtainable by algorithms developed to mitigate the detrimental impact of short-correlated nonlinear phase noise.

Nonlinear Phase-Shift Cancellation in Dispersion-Shifted Fiber Transmission by All-Optical Back-Propagation

Abstract: We experimentally demonstrate an unrepeatered system with optical phase conjugation (OPC)-based receiver-side back-propagation. Dispersion-shifted fibers employed for transmission simplify the OPC symmetry requirements, leading up to 2.93-dB SNR gains for dual-polarization 16-QAM signals.

Nonlinear Spectrum Compression of Negatively Chirped Picosecond Pulses in Dispersion-Shifted Telecom Fiber

Abstract: We investigated both experimentally and numerically self-phase modulation-induced spectrum compression dynamics of negatively chirped picosecond Gaussian pulses in the low-loss dispersion-shifted telecom fiber near its zero dispersion wavelength (ZDW). It was experimentally observed linearly interpolated monotonous increase in spectrum compression ratio (SCR) with negative chirp growth of the incident pulse in the range from −5.9 to −91.9. According to numerical simulations, despite its small values in the vicinity of ZDW, fiber dispersion limits both SCR growth and spectrum compression quality expressed in terms of time-bandwidth product value and energy confinement ratio at larger chirp values (|C| > 100), in a combined action with self-phase modulation (SPM). Having optimized fiber length and pulse energy, we achieved record 49.2-fold spectrum compression of 38.3-ps, 2.08 nJ negatively chirped Gaussian pulses with compressed spectrum FWHM of 0.23 nm and a50% energy confinement at 1560 nm wavelength, leading to a13.3-times spectral brightness magnification. We believe that results obtained can be promising for ultra-short pulse laser systems development with enhanced spectral brightness.

Distributed Temperature and Strain Sensing Utilizing Brillouin Frequency Shifts Contributed by Multiple Acoustic Modes in Dispersion-Shifted Fiber

Abstract: A multi-parameter sensor for distributed measurement of temperature and strain based on Brillouin scattering in dispersion-shifted fiber is proposed, which is an excellent candidate for the cross effects in traditional Brillouin sensing system. In experiment, a temperature accuracy of 2 °C, a strain accuracy of $60\ \mu\varepsilon$ are achieved simultaneously. © 2020 The Author(s)