研究目的
To propose and verify a passive technique for multiplexing spectrally overlapping optical network signals, enabling accurate recovery of individual spectra in applications like refractive index sensing.
研究成果
The proposed passive sub-carrier multiplexing technique effectively discriminates overlapped optical spectra with high accuracy (R2 ≥ 98.98%), offering an economical and scalable all-optical platform for optical sensing networks without the need for electro-optical modulators or strict synchronization.
研究不足
Potential errors from intensity noise, laser drift, and modulator transfer function drift. The system's response time is influenced by the speed of the TLS and ESA, and data processing is not real-time in this demonstration but could be optimized.
1：Experimental Design and Method Selection:
The system uses arrayed fiber delay lines to generate sub-carrier signals through temporal shifting, allowing multiplexing of devices with overlapping optical spectra. The principle involves pulse positioning via optical fiber delay lines to create intensity-modulated signals at unique sub-carrier frequencies.
2：Sample Selection and Data Sources:
Long-period gratings (LPGs) with overlapping optical spectra are used as sensors, immersed in Cargille oil with varying refractive indices for testing.
3：List of Experimental Equipment and Materials:
Includes a tunable laser source (TLS), polarization controller (PC), electro-optic modulator (EOM), digital pulse-pattern generator (PPG), erbium-doped fiber amplifier (EDFA), optical splitters and combiners, optical sub-carrier generators (with arrayed fiber delay lines), LPG sensors, optical/electrical converter (O/E converter), electrical spectrum analyzer (ESA), and optical spectrum analyzer (OSA).
4：Experimental Procedures and Operational Workflow:
Light from the TLS is modulated by the EOM using a 20 MHz pulse signal from the PPG, amplified by the EDFA, split into channels, each passed through an optical sub-carrier generator and LPG sensor, combined, converted to electrical signals by the O/E converter, and analyzed by the ESA. Optical spectra are reconstructed from electrical measurements using a normalization formula.
5：Data Analysis Methods:
Electrical peak powers are normalized to background and converted to optical powers using a logarithmic formula. The coefficient of determination (R2) is calculated to quantify resemblance between pristine and demultiplexed spectra.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容-
Electrical Spectrum Analyzer
N9320B
Agilent
Analyzes the electrical spectrum of the multiplexed signals.
-
Tunable Laser Source
AQ8201-13
ANDO
Provides swept wavelength light input for the system.
-
Digital Pulse-Pattern Generator
Generates the 20 MHz electrical pulse signal for modulation.
-
Electro-Optic Modulator
Modulates the light externally in response to the electrical pulse signal.
-
Erbium-Doped Fiber Amplifier
Amplifies the modulated optical signal.
-
Optical Spectrum Analyzer
Records the pristine output optical spectra for comparison.
-
Optical/Electrical Converter
Converts the multiplexed optical signal to electrical form for analysis.
-
登录查看剩余5件设备及参数对照表
查看全部
