Journals >Study On Optical Communications
Contents
2021
Volume: 47 Issue 2
15 Article(s)
Export citation format
Discussion on the Prospect of Informatization and Network Evolution
ZHANG Xin-quan, and YU Shao-hua
In recent decades, with the rapid progress of Information and Communications Technology (ICT), the impact of informatization on the social operation and human life is deepening. Based on the level of digitalization, networking and intelligentization, we review the history of informatization, and propose that the develoIn recent decades, with the rapid progress of Information and Communications Technology (ICT), the impact of informatization on the social operation and human life is deepening. Based on the level of digitalization, networking and intelligentization, we review the history of informatization, and propose that the development stage after digital twin will be digital intelligence and digital transcendence. As informatization is becoming the key driving force of network evolution in the future, we put forword 4 characteristics for the future network, namely network-computing collaboration, access collaboration, photo-electric cooperation and network intelligentization, and emphasize the key role and challenge of optical communication..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 1 (2021)
[in Chinese]
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 1 (2021)
Research on Industrial Internet Platform Architecture and Application based on Edge Intelligence 2.0
LIU Wei, and ZHANG Wei
Edge intelligence is the combination of Artificial Intelligence (AI) and edge computing, which can meet the key requirements of digital industry in real-time business, data optimization and intelligence application etc. In this article, we propose the concept of edge intelligence 2.0, and an industrial internet platforEdge intelligence is the combination of Artificial Intelligence (AI) and edge computing, which can meet the key requirements of digital industry in real-time business, data optimization and intelligence application etc. In this article, we propose the concept of edge intelligence 2.0, and an industrial internet platform based on open source framework is designed and built. Combining with the concept of cloud-network integration, cloud-edge collaboration and edge-edge collaboration, we achieve four in one collaboration of cloud, network, edge and terminal equipment. Finally, the edge intelligence technology is applied to Surface Mounted Technology (SMT) production line, through data modeling, analysis and optimizing technological parameters. Therefore, the manufacturing enterprises can reduce the costs and inventory with improved quality and efficiency..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 7 (2021)
Orthogonal Space Time Block Coding for Spatial Pulse Position Modulation
MAO Zhong-yang, LI Yin-long, LIU Xi-guo, XU Jian-wu... and WU Qiang|Show fewer author(s)
The system performance of Spatial Pulse Position Modulation (SPPM) is poor in turbulent channels. In order to solve this problem, the bit complement orthogonal space time Block Coding for Spatial Pulse Position Modulation (BCOSTBC-SPPM) is proposed by combining space-time block codes with spatial modulation technology The system performance of Spatial Pulse Position Modulation (SPPM) is poor in turbulent channels. In order to solve this problem, the bit complement orthogonal space time Block Coding for Spatial Pulse Position Modulation (BCOSTBC-SPPM) is proposed by combining space-time block codes with spatial modulation technology to improve the bit error rate performance using the space-time coding information redundancy. Based on Maximum Likelihood （ML） detection, the bit error rate expression of the proposed modulation is derived and is verified by Monte Carlo simulation. The simulation results show that compared with SPPM, the error performance of BCOSTBC-SPPM is greatly improved. At the bit error rate of 10-4, (4,2,4)-BCOSTBC-SPPM improves the signal-noise ratio by about 10 dB when comparing with (4,1,4)-SPPM under weak turbulence. Compared with the traditional orthogonal space-time coding scheme, this method has a certain improvement in spectrum efficiency, and realizes a reasonable trade-off between system effectiveness and reliability..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 14 (2021)
A Hybrid Dedicated Path Protection Strategy in EONs
ZHANG Sheng-feng, YUAN Qiang, CHEN Hui-dan, and HUANG Sheng
In order to reduce the bandwidth blocking rate and the consumption of spectrum resources in dynamic networks, the path conditions of different service requests may be different. Therefore, it is impossible to determine the advantages and disadvantages of single-path dedicated protection and partitioning dedicated path In order to reduce the bandwidth blocking rate and the consumption of spectrum resources in dynamic networks, the path conditions of different service requests may be different. Therefore, it is impossible to determine the advantages and disadvantages of single-path dedicated protection and partitioning dedicated path protection. In this paper, a Hybrid Dedicated Path Protection (HDPP) routing spectrum allocation strategy is proposed by combining single-path dedicated protection and partitioning dedicated path protection. This strategy considers the distance adaptive modulation and the number of path hops pre-calculated k link disjoint candidate paths. We also propose a Multiple Path Spectrum Assignment (MPSA) strategy that considers the highest spectrum efficiency per unit frequency slot with the number of path hops and the maximum available spectrum information on the path. HDPP selects the best scheme among multiple survivability routing spectrum allocation schemes. The simulation results show that the proposed algorithm has better performance in terms of blocking rate and spectrum utilization compared with other algorithms..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 20 (2021)
A Pre-equalization Method based on Prior Model in Underwater Optical Communication
ZHANG Lei, AO Jun, and SHI Jun-Jie
Due to seawater scattering characteristics, Inter-Symbol Interference (ISI) will occur in underwater transmission, especially in poor transmission environment. In order to solve this problem, pre-equalization technology is applied to underwater optical communication system based on Direct Current Offset Orthogonal FreqDue to seawater scattering characteristics, Inter-Symbol Interference (ISI) will occur in underwater transmission, especially in poor transmission environment. In order to solve this problem, pre-equalization technology is applied to underwater optical communication system based on Direct Current Offset Orthogonal Frequency Division Multiplexing (DCO-OFDM) modulation, and a pre-equalization method based on prior information is proposed. The performance of Turbid Harbor seawater channel is compared with that of traditional equalization algorithm. The simulation results show that the ISI in underwater optical communication system can be effectively reduced, as well as the Bit Error Rate (BER). The reliability of channel estimation can be improved under the condition of poor Signal Noise Ratio (SNR). Compared with the Least Squares (LS) post-equalization, LS pre-equalization and Mini-mental State Examination (MMSE) algorithms, the BER can be reduced by ~3.56, ~3.00 and ~1.85 dB, respectively..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 26 (2021)
Wide-band Bending Insensitive Multimode Fiber
SHEN Yi-chun, JIANG Xin-li, FAN Yan-ceng, and XU Wei-wei
In order to further improve the multimode fiber transmission performance in the Ethernet, the paper proposes to improve the performance of wide-band bending insensitive multimode fiber considering the material composition and profile structure design. By optimizing the concentration distribution of the doped elements iIn order to further improve the multimode fiber transmission performance in the Ethernet, the paper proposes to improve the performance of wide-band bending insensitive multimode fiber considering the material composition and profile structure design. By optimizing the concentration distribution of the doped elements in the core, the sensitivity between the parameter of optimal profile refractive index distribution αopt and the wavelength is reduced, and the fiber bandwidth characteristics is improved. In addition, the new design contains an inner cladding which can adjust the profile structure continuously at the interface of core and cladding. The continuous adjustable structure can reduce the influence of viscosity difference between the core layer and the trench on the fiber performance. It can also alter the delay of higher-order modes very effectively to eliminate the impact of trench structure on fiber bandwidth characteristics, by adjusting inner cladding profile. The results show that the fiber with the new structure has not only higher bandwidth characteristics, but also lower bending loss..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 31 (2021)
Research on the Displacement Sensing Structure with Varied Line-space Grating and Its Error Analysis
QIAO Fei, ZHANG Wen, HE Wei, SONG Yan-ming, and MENG Fan-yong
Due to the low measurement precision, small measurement range and low stability of traditional displacement sensors, this paper propose and implement a displacement sensor based on varied line-space grating, with the displacement characteristic test and the error problems in the measurement process are accomplished andDue to the low measurement precision, small measurement range and low stability of traditional displacement sensors, this paper propose and implement a displacement sensor based on varied line-space grating, with the displacement characteristic test and the error problems in the measurement process are accomplished and analyzed, respectively. In the experiment, the varied line-space grating is placed on the electric displacement platform. The incident position of the light spot is controlled by adjusting the displacement of the platform. Besides, the correlation between the grating displacement and the wavelength of the reflection spectrum first-order diffraction center is established to realize the wavelength coding of the displacement. The platform movement range is 0~20 mm, with step length of 2 mm, and the round trip repeated measurement is made for 6 times. The central wavelength at each shift point is recorded and the displacement characteristics of the sensor are calibrated. Based on the error analysis of the central wavelength data generated by repeated measurements at each shift point, the standard deviation of multiple measurements at each point is analyzed by using Bessel formula combined with the Pieters method. The reliability of the data is further determined by combining with the 3σ criteria. The experimental results show that the sensor system has no systematic error and gross error. Also, the wavelength and displacement of the sensor change linearly, and the linearity of multiple repetitions is better than 0.994 6. The average displacement sensitivity of the sensor’s full range is 16.67 nm/mm. The content of this paper can provide a certain research reference for displacement sensing system based on varied line-space grating..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 35 (2021)
Optical Properties and Filtering Applications of Coaxial Gold Nanotube Ordered Array
CHENG Jian-xin, ZHOU Ying, CHANG Jian-hua, and NI Hai-bin
In order to realize the multi-band tunable filtering of the metamaterial filter in the visible and near infrared bands, the ordered array of coaxial gold nanotubes is numerically simulated by using the Finite-Difference Time-Domain method. We investigate the absorption characteristics of cylindrical surface plasmons asIn order to realize the multi-band tunable filtering of the metamaterial filter in the visible and near infrared bands, the ordered array of coaxial gold nanotubes is numerically simulated by using the Finite-Difference Time-Domain method. We investigate the absorption characteristics of cylindrical surface plasmons as well as gap surface plasmons in the ordered array and explore their applications in the filtering fields. Then we analyze the influence of structural parameters on the number and location of resonant wavelengths. The simulation results show that multi-band tunable filtering can be realized in the range of 600~1 700 nm by adjusting the structural parameters..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 41 (2021)
Design and Study on 25 Gbit/s Optical Transmitter Module based on Silicon Optical Scheme
CHENG Xuan-xuan, ZHAO Jian-yi, XIAO Xi, LI Miao-feng... and CAI Jing|Show fewer author(s)
With the rapid development of optical communication technology, the capacity of optical transmission increases dramatically. The flexible requirements for the management and scheduling of Dense Wavelength Division Multiplexing （DWDM）network systems also become higher. The wavelength adjustable module can meet the requiWith the rapid development of optical communication technology, the capacity of optical transmission increases dramatically. The flexible requirements for the management and scheduling of Dense Wavelength Division Multiplexing （DWDM）network systems also become higher. The wavelength adjustable module can meet the requirements of flexible network management, which will be widely used in Wavelength Division Multiplexing （WDM） system and 5G network. As the core component in the module, the research of tunable laser is particularly important. This paper introduces the hybrid integrated package technology of tunable laser and silicon modulator chip, which uses the design of an etalon a gluing standard to control the wavelength, saving the design of semiconductor refrigerator and the package size. The tunable laser produced meets the wavelength output requirements of ITU-96 channel, and the eye map meets the working eye map of 100 G Base-LR4 international standard..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 48 (2021)
Design Technique for Transimpedance Amplifier using gm/Id Methodology
LIN Jia-hui, and JIANG Xiang
Aiming at the high complexity of the mathematical model of short channel transistor, a gm/Id method is proposed to describe the short channel transistor model. This method optimizes the circuit performance by establishing the relationship between the circuit index and transistor size. The experiment result shows that tAiming at the high complexity of the mathematical model of short channel transistor, a gm/Id method is proposed to describe the short channel transistor model. This method optimizes the circuit performance by establishing the relationship between the circuit index and transistor size. The experiment result shows that the transimpedance amplifier with a photodetector capacitance of 250 fF can achieve a gain of 59.72 dBΩ, a bandwidth of 3.445 GHz, an input referred current noise of 6.209×10-3 nA/sqrt/Hz and equivalent input noise current of 876.0 nA. The design dissipates 7.5 mW from a 1.2 V supply. The test results show that, when 100 μA current is input, the peak to peak data jitter of the circuit is about 64.92 ps, and the output swing is 81.1 mW..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 54 (2021)
Design and Development of 25 Gbit/s TOSA based on MWDM
HU Ting, LE Huan, GAO Jian-he, ZHENG Qing-li... and XU Hong-chun|Show fewer author(s)
5th-Generation (5G) fronthaul is an important part of the bearer network. High-precision time synchronization and massive connection requirements may have higher demands on the access network. In order to solve the problems of fronthaul dumb resource management and optical fiber resources, China Mobile proposed a Mediu5th-Generation (5G) fronthaul is an important part of the bearer network. High-precision time synchronization and massive connection requirements may have higher demands on the access network. In order to solve the problems of fronthaul dumb resource management and optical fiber resources, China Mobile proposed a Medium Wavelength Division Multiplexing (MWDM) fronthaul solution. In view of the demand of MWDM scheme and the need to reduce the cost in the implementation of 5G fronthaul, a 25 Gbit/s Transmitter Optical Subassembly (TOSA) for MWDM optical module is proposed in this paper, which is packaged with low-cost and hermetic coaxial structure. Built-in thermo electric cooler is also used to support the harsh conditions of outdoor scene. This paper mainly introduces the key design and packaging form of TOSA, and optimizes its temperature control ability from the design and process. Finally, the photoelectric performance, temperature control ability and transmission performance of the sample are tested. The results show that the device has excellent performance, which also meet the SFP28 package form and IEEE 802.3 protocol standards..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 59 (2021)
Research on High Power Remote Pump Transmission System
HOU Meng-jun, FU Cheng-peng, BU Qin-lian, YU Chun-ping, and LE Meng-hui
The transmission distance of high power pump in the remote pump transmission system is limited. Considering this issue, a novel remote pump transmission scheme is proposed based on the principle of the randomly distributed feedback fiber laser, which enhances the stimulated Raman effect of the pump and outputs the targThe transmission distance of high power pump in the remote pump transmission system is limited. Considering this issue, a novel remote pump transmission scheme is proposed based on the principle of the randomly distributed feedback fiber laser, which enhances the stimulated Raman effect of the pump and outputs the target pump power through the fiber Bragg grating with high reflectivity. The transmission performance of the new remote pump transmission system is tested. The experimental results show that the experimental data and theoretical calculation data of the new remote pump transmission system are consistent. Compared with the remote pump transmission system, the new remote pump transmission system improves the fiber input power of the pump and extends the transmission distance of the transmission system..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 63 (2021)
A Method for MEMS Optical Switches in Power Systems
RUAN Jun, DU Hao-tao, ZHU Zhi-jun, and SUN Hao
The Micro-Electromechanical System (MEMS) optical switches in power systems may be affected by optical control signals during fiber switching, which may cause damage to Optical Time-Domain Reflectometer （OTDR）. In order to solve this problem, this paper proposes a method to optimize the switching path of MEMS optical sThe Micro-Electromechanical System (MEMS) optical switches in power systems may be affected by optical control signals during fiber switching, which may cause damage to Optical Time-Domain Reflectometer （OTDR）. In order to solve this problem, this paper proposes a method to optimize the switching path of MEMS optical switches in power systems. After the optical switch performing a complete scan, the accurate optical signal channel power contour map is obtained, and then the switching path is optimized and controlled. Therefore, the MEMS optical switch can achieve the highest relative channel isolation of incident light along the premise of balancing the control channel switching time. The best path for switching control can also be used to minimize the impact of the MEMS optical switch on other channels when switching under the premise of ensuring the switching time, and it will not be affected even in a very complicated channel environment..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 66 (2021)
Research Progress of Terahertz Wave Radiation Source
WANG Ge, SHI Ming-deng, HAN Qing-hua, MENG Hong-bing, and ZENG De-bin
Terahertz band in electromagnetic spectrum has many properties than traditional light source, which has very important research value in biology, material, security, communication and other fields. The high power and high efficiency terahertz radiation source is an important factor and prerequisite for the transformatiTerahertz band in electromagnetic spectrum has many properties than traditional light source, which has very important research value in biology, material, security, communication and other fields. The high power and high efficiency terahertz radiation source is an important factor and prerequisite for the transformation of terahertz technology into actual productivity. In this paper, the research progress of terahertz wave generated by laser interacting with different excitation media is summarized from the perspective of gas, solid and liquid as excitation media. The physical mechanism of four-wave mixing, mass-dynamic, cherenkov and photocurrent models commonly used in gas media, as well as the physical mechanism of photoconductance and photorectification models in solid media are described in detail, and the factors affecting the generation of terahertz waves by these excitation media are analyzed and summarized. Finally, the methods of producing terahertz radiation source by liquid excited medium are prospected..
Study On Optical Communications
- Publication Date: Aug. 22, 2021
- Vol. 47, Issue 2, 70 (2021)
© Copyright 2018-2021 | Chinese Laser Press. All Rights Reserved 沪ICP备15018463号-20