- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Solution-Process ZnO-Mediated Semiconductor Bonding for Photovoltaic Applications
摘要： We propose and demonstrate frequency-comb regeneration using injection locking and a parametric mixer. We theoretically evaluate the effect of the dispersive walk-off between the two unmodulated carriers from which the comb is regenerated. We calculate the maximum number of carriers which can be regenerated as a function of the laser linewidth and transmission distance when considering dispersion-unmanaged links. Experimentally, we demonstrate a 70 line comb generation without major linewidth degradation from two carriers with 15 dB optical signal-to-noise ratio (OSNR). The low OSNR operation is achieved by the use of optical injection locking. We also evaluate the degradation in the comb regeneration when the carriers are temporally decorrelated in order to emulate the effect of dispersive walk-off. When the temporal delay is 1.5 ns, the comb regeneration does not suffer from major degradation but when the delay is 10 ns, only 30 carriers can be regenerated without linewidth degradation, which agrees with our theoretical analysis.
关键词： parametric devices,optical fiber communications,Homodyne detection
更新于2025-09-19 17:13:59
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Special Issue on Advanced DSP Techniques for High-Capacity and Energy-Efficient Optical Fiber Communications
摘要： The rapid proliferation of the Internet has been driving communication networks closer and closer to their limits, while available bandwidth is disappearing due to ever-increasing network loads. In the past decade, optical fiber communication technology has increased the per fiber data rate from 10 Tb/s to over 10 Pb/s. A major explosion came after the maturity of coherent detection and advanced digital signal processing (DSP), which enabled the achievement of high spectral and energy efficiency. It is difficult to overstate the impact that optical coherent technologies have had in both generating and supporting the revolution of optical communications over the last 10 years.
关键词： high-capacity,optical fiber communications,energy-efficient,DSP techniques
更新于2025-09-19 17:13:59
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Optical Fiber Communications (Principles and Applications) || Optical Amplifiers
摘要： An optical amplifier is a widely used device in optical fiber communications for the purpose of amplification of the optical signal generated by an optical transmitter. The optical signal is directly amplified to yield optical signal without any conversion to electrical signal first and then restoring it to amplified optical signal. This implies that optical amplifiers operate on photons in all-optical domain. In essence, optical amplifiers do require source and photodetector as optoelectronic devices and additional electronic circuits for other operations such as shaping of optical pulses including retiming. But why do we need optical amplifiers? We know that typical fiber loss around 1500-nm wavelength is approximately 0.2 dB/km. Let us examine what happens after the optical signals travel about 100 km down the fiber. The signals are attenuated by 20 dB. So they need to be amplified, otherwise the signal-to-noise ratio of detected signals is too low and bit-error-rate becomes too high (typically desired value of BER is <10-9). One way to resolve this issue is to detect the weak signals, followed by modulating a new laser (optical-to-electrical-to-optical conversions) which requires high-speed (>10 GHz) electronic circuitry. Therefore, the best way to amplify the signal is only optically and the preferred method is fiber amplifier which is the most efficient, the most stable and the one with the lowest loss.
关键词： Erbium-doped fiber amplifiers,Raman fiber amplifiers,optical amplifiers,semiconductor optical amplifiers,optical fiber communications
更新于2025-09-12 10:27:22
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Optical Fiber Communications (Principles and Applications) || Optical Sources and Transmitters
摘要： An optical source provides the electrical–optical signal conversion efficiently that enables the optical output to be effectively coupled and launched into the optical fiber. It is an active device that requires external power supply for operation in optical fiber communications. This chapter begins with the major requirements or desirable properties for the optical source in general. Light emitting diodes (LEDs) and injection laser diodes (ILDs) {which are simply known as laser diodes (LDs)} are the most popular semiconductor optical sources. LED is an incoherent optical source. It can support many propagation modes of light within its structure. This is the reason why is it employed as a multimode optical source. Whereas, ILD is a highly coherent optical source that has a very narrow spectrum and fast response time. Thus, it is mostly used as a single-mode optical source in single-mode propagation requirements. In this chapter the basic principle of operation of both these optical sources along with their major structures and configurations are described. For producing the light signal, the emission can be a spontaneous emission, as in the case of LED, or a stimulated emission as in the case of ILD. The spontaneous emission takes place when electrons are brought to a very high energy level, and an unstable state. The electrons will return spontaneously (within few picoseconds) to a stable state, and will consequently emit photons.. The optical wavelength is determined by the amount of energy the electron releases. A laser diode operates with stimulated emission in which the electrons enters and stays in a high-energy state for a few microseconds. Then it changes its state spontaneously. During this state, the photon stimulates so as to emit the energy in the form of another photon. Thus, the laser produces the light signal. Finally, a typical functional block schematic including features and operations of optical transmitter is covered to assess the utility of optical sources.
关键词： LED,spontaneous emission,optical transmitter,optical sources,stimulated emission,laser diode,optical fiber communications
更新于2025-09-12 10:27:22
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Optical Fiber Communications (Principles and Applications) || Optical Measurements
摘要： Optical measurements are necessary to verify the operational characteristics of the optical fiber communication link. Various measurement techniques and special-purpose test equipments are employed for determining key performance parameters of the constituent components and devices including the optical fiber. It is quite obvious that optical measurements are needed at different levels of research and design, manufacturing and production of optical components and devices, installation and commissioning of optical fiber communication systems in the field. There is wide variety of optical measurement and test equipments used. These include optical power meter, optical oscilloscope and spectrum analyzer, optical time-domain reflectometer (OTDR), optical waveform analyzer, connector inspection microscope, dispersion analyzer, live fiber detector, talk-set, optical test set (combined source and power meter), etc. All these measurements are wavelength specific. Fiber attenuation and occurrence of faults in the optical fiber link is the main concern in ensuring the desired performance. There are several challenges involved with optical measurements like multiple wavelengths/channels, high optical power levels, need to carry tests remotely along with a high degree of automation.
关键词： OTDR,optical measurements,spectrum analyzer,optical power meter,optical fiber communications
更新于2025-09-12 10:27:22
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[IEEE 2018 20th International Conference on Transparent Optical Networks (ICTON) - Bucharest (2018.7.1-2018.7.5)] 2018 20th International Conference on Transparent Optical Networks (ICTON) - Machine Learning Based Optimal Modulation Format Prediction for Physical Layer Network Planning
摘要： Physical layer network design and planning process is a cumbersome one. It includes laying out all possible combinations of modulation formats, fiber types, forward error correction codes, channel spacing, etc., conducting exhaustive simulations and lab experiments to come up with carefully tuned engineering rules, and finally using these approximate models to propose transmission feasibility. Besides being cumbersome, there are two fundamental issues in conventional network planning approach, firstly it almost exclusively offers conservative design, leading to resource underutilization, and secondly it’s not scalable – neither from planning viewpoint nor computationally – to next-generation highly granular and flexible networks. Machine learning, an artificial intelligence toolset, may be applied to solve aforementioned issues by allowing data-driven model development, and consequent transmission quality prediction. While network planning is an extensive topic, in this paper, we focus on neural network based modulation format classification, autonomously identifying best possible modulation format for a given link configuration.
关键词： machine learning,analytics,communication networks,optimization,optical fiber communications
更新于2025-09-10 09:29:36