由于周边环境复杂、倒塌空间有限，厂区内210 m高烟囱爆破拆除施工必须保证定向爆破的精准度与安全性。根据理论计算与工程经验选取正梯形爆破切口、切口高度为4.5 m，切口圆心角为216°，烟囱外壁单耗为2.3 kg/m3，内村单耗为1.45 g/m3。通过优化开凿工艺、爆破参数以及起爆网路等控制措施控制爆破次生灾害; 采用混合材料悬挂式覆盖防护、减震堤等安全措施控制爆破负面效应。最终爆破取得了良好效果，周边建(构)筑物在爆破过程中没有受到损伤，监测的振动峰值为0.27 cm/s。
钢筋混凝土烟囱 复杂环境 定向爆破 安全防护 reinforced concrete chimney complex environment directional demolition blast safety protection
光子学报
2021, 50(12): 1217001
1 中国科学院上海光学精密机械研究所空间激光信息传输与探测技术重点实验室，上海 201800
2 中国科学院大学材料与光电研究中心，北京 100049
3 中国科学院上海光学精密机械研究所中国科学院量子光学重点实验室，上海 201800
分布式光纤声波传感（DAS）技术以独特的动态在线监测、大范围密集测量、方便布设免维护等优势，获得了周界安防、结构健康、交通运输、油气勘探、海洋水声等多领域专家学者的广泛关注。同时，DAS技术可以方便地通过标准通信光缆或专用光缆形成大规模探测阵列，满足地球物理与自然灾害预测等领域的地震波检测需求，有望得到更广泛的应用。以新兴的地震波检测应用为切入点，结合调研情况，对DAS技术的基本传感原理、技术发展历程、地震波应用进展等进行论述，并分析DAS在地震波检测方向所面临的关键技术难题和未来发展趋势。
激光与光电子学进展
2021, 58(13): 1306006
1 电子信息控制重点实验室, 四川 成都 610036
2 中国科学院上海光学精密机械研究所空间激光信息传输与探测技术重点实验室, 上海 201800
3 中国科学院上海光学精密机械研究所中科院量子光学重点实验室, 上海 201800
随着高精度光钟及其各种应用的发展,人们对时频传输技术的精度要求越来越高。基于光纤的时频传输技术已经较为成熟,而自由空间激光时频传输技术可以应用在不方便铺设光纤、快速机动场合以及星地、星间时频传输领域。介绍了国内外在近地空间以及星地间进行时频传输的研究现状,并对其未来的发展趋势进行了展望。未来自由空间激光时频传输将会朝更高的传输精度、时频传输、测距、通信一体化以及时频空间组网的方向发展。
光通信 时频传输 自由空间 光钟比对 光频梳 激光与光电子学进展
2020, 57(17): 170004
Author Affiliations
Abstract
1 Key Laboratory for Quantum Optics, CAS, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China
3 Shanghai Key Laboratory of All Solid-State Laser and Applied Techniques, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
4 e-mail: hwcai@siom.ac.cn
Based on dense wavelength-division multiplexing technology, frequency transfer and time synchronization are simultaneously realized over a compensated cascaded fiber link of 430 km, which is a part of the Beijing–Shanghai optical fiber backbone network. The entire cascaded system consists of two stages with fiber links of 280 and 150 km, respectively. To keep high symmetry and low noise, specific bi-directional erbium-doped fiber amplifiers are used to compensate the large optical attenuation of each fiber link. When the compensation servo is active in every stage, the cascaded system achieves the stability of 1.94×10 13 at 1 s and 1.34×10 16 at 104 s, for frequency transfer. It is also verified that the actual results of the cascaded system are in good agreement with the theoretical ones calculated from error theory. Simultaneously, after calibration of each stage, time synchronization is also realized. The final accuracy of the whole system is within 94 ps.
060.2360 Fiber optics links and subsystems 060.2340 Fiber optics components 120.7000 Transmission Chinese Optics Letters
2016, 14(7): 070602
1 中国科学院上海光学精密机械研究所中科院量子光学重点实验室, 上海 201800
2 中国科学与技术大学量子信息与量子科技前沿协同创新中心, 合肥 安徽 230026
3 中国科学院上海光学精密机械研究所上海市全固态激光器与应用技术重点实验室, 上海 201800
通过级联方式在京沪光纤骨干网中实现了430 km的高精度频率传递。该级联系统包含了280 km和150 km两级系统,同时为了补偿光纤损耗,在两级链路中采用了低噪声高对称的双向掺铒光纤放大器。当每一级传递系统通过光学补偿方式达到稳定后，整个级联系统引入的频率不稳定度为在1 s处1.02×10-13和在104 s处8.24×10-17，实验结果验证了级联系统的实际结果与两级系统计算结果之间符合误差理论。
光纤光学 频率传递 级联系统 光学补偿
1 中国科学院上海光学精密机械研究所上海市全固态激光器与应用技术重点实验室, 上海 201800
2 中国科学院上海光学精密机械研究所中国科学院量子光学重点实验室, 上海 201800
3 中国科学技术大学量子信息与量子科技前沿协同创新中心, 安徽 合肥 230026
为实现准国土范围内高精度授时和守时，利用光纤传递铯钟、氢钟等高精度原子钟的时频信号，在实际光纤链路上验证其长距离传递性能。采用波分复用和双向双波长的传输方法，介绍了在275 km京沪干线上实现高精度时频传递的相关工作。针对长距离光纤链路的特点，探讨了链路损耗与散射、色散与频率噪声、补偿系统动态范围和反馈带宽等对时频传递性能的影响。实验获得了频率信号的秒稳定度达5×10-14和天稳定度达7×10-18的传递性能，同时，千秒尺度下的时间方差可达2.4 ps。
光纤光学 时频传递 时间同步 波分复用
1 中国科学院上海光学精密机械研究所中科院量子光学重点实验室, 上海 201800
2 中国科学院上海光学精密机械研究所上海市全固态激光器与应用技术重点实验室, 上海 201800
The joint transfer of frequency and one pulse-per-second time signals based on dense wavelength division multiplexing technology is demonstrated over a compensated cascaded fiber link of 230 km, consisting of two stages of fiber links with lengths of 150 km and 80 km . A bi-directional erbium-doped fiber amplifier is inserted in the center of 150 km fiber link to compensate for significant optical attenuation. After every stage has achieved the steady state by optical compensation, the Allan deviation of frequency signal of the cascaded system is 3.1×10-14 at 1 s and 6.3 × 10-18 at 104 s respectively; the time deviation of time signal is less than 3.5 ps at an averaging time of 102 s to 104 s. Further, it is verified that the stability of the cascaded link is the standard deviation of the stabilities of the two stages links for both frequency and time signals. After calibration, time synchronization is also realized and the accuracy is within 90 ps.
1 中国科学院上海光学精密机械研究所上海市全固态激光器与应用技术重点实验室, 上海 201800
2 中国科学院上海光学精密机械研究所中科院量子光学重点实验室, 上海 201800
提出了一种应用于光纤时间频率传递系统中时间信号的校准和同步方案。分析了基于光学补偿方式和波分复用技术的时频传递系统中本地和远地时间信号同步方案的原理，并完成了实验室内50 km 光纤链路的验证实验，时间同步精度为1.6 ps。在110 km 的商用光纤链路上完成了时间信号的同步实验，理论计算的时间同步精度为30.0 ps，对时间信号的误差来源进行了理论分析。
光纤光学 时频传递 时间同步 光学补偿 波分复用
Author Affiliations
Abstract
1 Key Laboratory for Quantum Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 Shanghai Key Laboratory of All Solid-State Laser and Applied Techniques, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
In an experiment on the round-trip fiber transfer of joint frequency and time signals based on wavelength-division multiplexing technology, a specific bidirectional erbium-doped fiber amplifier (Bi-EDFA) with low noise and high symmetry simultaneously is designed and applied to compensate for the loss of the link. The Allan deviation (ADEV) deterioration of the 1 GHz frequency signal induced by the Bi-EDFA is only 8×10 15 at 1 s and 9×10 18 at 104 s in the forward direction, and is 1.7×10 14 at 1 s and 1.2×10 17 at 104 s in the backward direction. The degraded time deviation (TDEV) caused by the asymmetry of the Bi-EDFA is only 0.8 ps at an average time of 103 s. With the proposed Bi-EDFA, in the field experiment on the 110 km fiber transfer of joint frequency and time signals, the ADEV of the 1 GHz frequency signal is 7.3×10 14 at 1 s and 2.5×10 17 at 104 s. The TDEV of the 1 pulse per second time signal is 6.8 ps with an average time of 1
060.2320 Fiber optics amplifiers and oscillators 060.2360 Fiber optics links and subsystems Chinese Optics Letters
2015, 13(11): 110601
