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A novel humidity sensor, which is based on Michelson interferometer (MI) with thin core fiber (TCF) coated with chitosanis proposed and experimentally demonstrated. Its principle is that the light in the single-mode fiber (SMF) core is excited into the cladding of the TCF, and the light transmitted from the end face of the TCF is reflected back to the SMF core. When the chitosan is coated on the end...
Aiming at providing united control of multi-domain optical networks orchestration, we design the Federated Platform based on Open Network Operating System (ONOS). Our implementation includes adding and extending modules in ONOS to provide the global view of multi-domain networks and support cross-domain end-to-end services by communicating with the individual domain controllers through RESTCONF protocol...
In this paper, the OSNR expressions for the cascaded system in the practical optical network is derived from the definition of OSNR. Then we analyse the OSNR changes in optical channels resulted from the variation of network topology, which is verified by optical network simulation software at the end of the paper.
We investigate the temperature dependence of CrossTalk (CT) for PANDA Polarization maintaining fiber (PMF). The test temperature ranges from −55 to 85 °C, and the tested fiber was loose wound. The mismatch in thermal expansion coefficient between the boron-doped parts and the core can be varied by controlling the doping concentration in the stress and core regions. The whole temperature CT variation...
The comb filters consist of few mode fiber and standard single mode fiber suffer from low extinction radio. Replacing standard single mode fiber with small-mode-area fiber can better the balance excitation in few mode fiber, thus improve the extinction radio. A lab-made small-mode-area single mode fiber was utilized to a commercial few mode fiber and increase the extinction radio from 2.5dB to 6.5dB...
We study the artificial neural network (ANN) and feed forward equalizer jointly to mitigate the inter-symbol interference (ISI) and the nonlinear distortions in the optical single-side band and direct-detection (DD) system. The optical SSB signal is generated by a relatively low-cost dual-drive Mach-Zehnder modulator (DDMZM). The two driving signals are a pair of Hilbert signals with Nyquist pulse-shaped...
A novel side-excitation fiber-optic laser-ultrasound transducer based on fused taper fiber is proposed and demonstrated. The transducer achieves ultrasound generation at optical fiber sidewall and performs a relative high conversion efficiency. In the experiments, 514 mV peak-to-peak power ultrasound wave has been obtained at the fiber sidewall with input 0.04 mJ laser pulse. Theoretical analysis...
High extinction ratio is needed in high precision Optical Time Domain Reflectometer (OTDR) to enlarge the dynamic range. By transmitting part of pulse signal modulated by a Mach-Zehnder (MZ) optical modulator back to the input of the modulator via a feedback circuit, the pulse signal can be multi-modulated by one MZ optical modulation. And this technique offers great enhancements in the performance...
We propose and demonstrate a cascaded-cavities Fabry-Perot interferometer (FPI) for simultaneous measurement of pressure and temperature based on photonic crystal fiber. The sensor is composed of cascaded air-cavity and silica-cavity. The air-cavity and silica-cavity are both sensitive to temperature and pressure because of the thermo-optic coefficient and Young's modulus. We can obtain the pressure...
Due to the unique data structure, the big datagram is prone to packet loss during the network outburst transmission process, especially in the space TT&C (Tracking, Telemetry and Communication) network which is very strict in real time. This paper focuses on the analysis of the transmission mechanism of big datagram, expatiates its fragmentation, reorganization and Re-fragmentation mechanism....
A tadpole-shape fiber sensor, with S-bend fiber cascading spherical shape, has been proposed and experimentally realized in this work. In our experiments, the output spectrum of the proposed sensor was found to be shifted with the changing of the refractive index and the temperature. Experiments results showed that the highest sensitivity of the refractive index was up to −114.845nm/RIU with a wide...
A compact open-path tunable diode laser absorption spectrometry (TDLAS) sensor has been developed for gas-phase hydrogen peroxide (H2O2) concentration monitoring during sterilization and aseptic disinfection. The sensor was based on a open-path multi-pass Herriott cell and wavelength modulated near-infrared diode laser. The sensor was calibrated by titrating the H2O2 water which was obtained by exhausting...
Detection of trace chemicals sensitively and selectively is important for environmental, safety and industrial process monitoring. Based on erbium-doped photonic crystal fibre (ED-PCF) laser intra-cavity absorption spectroscopy detection technology, analyzing the infrared absorption spectrum of acetylene (C2H2) gas. The relationship between the gas concentration and the absorption of C2H2 at the normal...
In this paper, a high frequency vibration detection system of optical fiber sensing has been designed based on facet reflection principle, to satisfy the requirements of high frequency vibration measurement, including aerospace and fault diagnosis of high-speed rotating machinery, etc. The system modulates high frequency vibration signal by using the reflective intensity modulation fiber-optic sensor...
Real-time and accurate detection of the flammable gas concentration is the key issue in spontaneous combustion prediction. A modified tunable diode laser absorption spectroscopy (TDLAS) technology has been used in this paper to achieve in-situ detection of trace Acetylene concentration. Noises and interference fringes are eliminated by wavelet adaptive threshold filtering, and then Kalman filtering...
Optical sinusoidal wave generation on four channels simultaneously is experimental demonstrated using a self-starting optoelectronic oscillator. The frequency of the sinusoidal wave can be widely tuned from 25 GHz to 200 GHz with 25-GHz spacing. The timing jitter of the microwave signal extracted from the oscillator is measured to be 218 fs.
A digital free-space optical (FSO) communication over 1km based on double-channel dense wavelength division multiplexing (DWDM) is experimentally demonstrated. We successfully achieve multiplexing and demultiplexing of signals with different rates and different code types.
We propose an accurate laser linewidth estimation technique based on the decision-aided maximum likelihood carrier phase estimator (DA-ML). Its performance is verified in M-ary quadrature amplitude modulation (MQAM) within a wide range of the laser linewidths and SNR values.
We propose a novel cost-effective mode division multiplexing and wavelength division multiplexing (MDM-WDM) reconfigurable optical Add/Drop multiplexer (ROADM) scheme based on wavelength reuse and experimentally demonstrate its feasibility. The proposed scheme could reduce system cost and simplify the wavelength management.
One main challenge in network virtualization is virtual network embedding (VNE). VNE is NP-hard. Previous VNE algorithms in the literature are mostly heuristic, while the remaining algorithms are exact. To make a trade-off between the heuristic and the exact, this paper proposes the algorithm VNE-RSOT, based on restrictive selection and optimization theory, to solve the VNE problem. The restrictive...
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