The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform
Huajun Yang - One of the best experts on this subject based on the ideXlab platform.
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Improving the transmission efficiency of the Cassegrain optical system for Bessel–Gaussian beams
Applied Optics, 2020Co-Authors: Huajun Yang, Ping Jiang, Weinan Caiyang, Miaofang ZhouAbstract:With the improvement of the transmission efficiency, the Cassegrain antenna can be widely used in space optical communication. In this paper, the Bessel–Gaussian (BG) beam is used to avoid the central energy loss of a Cassegrain antenna system. The intensity distribution and the phase distribution of the BG beam passing through a Cassegrain antenna are theoretically derived and simulated. At a wavelength of 1550 nm, this method can theoretically improve the transmission efficiency to approach 100% under the situation in which the obscuration ratio is nonzero, and the transmission efficiency can reach more than 80% when obscuration ratio is in the range of from 0 to 0.1252 with $l=4$l=4. The effects of on-axial defocusing on the light field and the transmission efficiency are studied. The method proposed in this paper can remarkably improve the transmission efficiency of a Cassegrain antenna in a practical and uncomplicated approach.
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structure design of a conic lens pair for improving the transmission efficiency of a Cassegrain antenna
Applied Optics, 2019Co-Authors: Miaofang Zhou, Huajun Yang, Ping Jiang, Weinan CaiyangAbstract:Central energy loss is a critical factor decreasing the transmission efficiency of a Cassegrain antenna. In this paper, a pair of conic lenses are designed and set in front of a Cassegrain antenna to improve the transmission efficiency of the antenna instead of designing a complicated antenna structure. On the basis of the analysis, the optimized conic lens pair can theoretically improve the transmission efficiency up to 100% at a wavelength of 1550 nm under ideal conditions. After several practical factors are considered, such as the dispersion of the material, the transmissivity and chamfering of the conic lens, and the reflectivity of the mirrors composing the Cassegrain antenna, the conic lens pair can still increase the transmission efficiency of the Cassegrain antenna up to 92.37% at a wavelength of 1550 nm. Compared with designing a complicated antenna, the method proposed here provides a more practical approach to improve the transmission efficiency of a Cassegrain antenna.
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On-axial defocused characteristic analysis for Cassegrain antenna in optical communication
Optik, 2016Co-Authors: Minyin Yu, Huajun Yang, Ping Jiang, Yao Zhang(, Lu ChenAbstract:Abstract In order to reduce the chromatic aberration problem of the multiple wavelength, reflex Cassegrain antenna is widely used in space optical communication system. There are many external factors such as temperature and vibration that may cause defocusing in practice which has influence on Cassegrain antenna. That is to say, the primary mirror's and the secondary mirror's focus cannot be coincided, so it will bring impact greatly on transmission efficiency. This paper studies the effects on the transmission characteristics of the defocused Cassegrain antenna system. While defocused 2.5 cm, the transmission efficiency of Cassegrain antenna will decrease 80% of the initial efficiency. So it is very important to maintain optimum position for high transmission efficiency.
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Optimizing the secondary mirror structure parameters for Cassegrain antenna
Optik, 2015Co-Authors: Minyin Yu, Huajun Yang, Ping Jiang, Wensen HeAbstract:Abstract Cassegrain antenna is a very important type of optical antenna, which is widely used in space optical communications. However, the secondary mirror barrier may cause lower transmission efficiency in practice. This paper studies the factors affecting the transmission efficiency of the Cassegrain antenna system. Then, a series of optimum structure parameters are obtained, achieving a transmission efficiency of 91.6%. Therefore, this antenna can increase the transmission efficiency to a great extent in optical communication systems.
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An optimum analysis for Cassegrain optical antenna
Optik, 2015Co-Authors: Xiaojun Ma, Huajun Yang, Bing Wang, Ping Jiang, Mingyin Yu, Yuchun Huang, Shasha KeAbstract:Abstract In this paper, the energy loss caused by the secondary mirror of Cassegrain antenna has been discussed numerically. As the diameter of the secondary mirror is one-fifth of the primary mirror, the loss goes beyond 18.5%. Because of the alignment of the optical system being the significant factor, it influences the transmission quality of the optical antenna system. We analyze and numerically simulate how power attenuation ratio and gain of Cassegrain antenna vary with the antenna deflection, and measure the distance such that the central axis of the receiving antenna deviates from the z -axis in case of occurrence of off-axis space in the system. Finally, an optimum structure is proposed by trepanning the secondary mirror.
Ping Jiang - One of the best experts on this subject based on the ideXlab platform.
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Improving the transmission efficiency of the Cassegrain optical system for Bessel–Gaussian beams
Applied Optics, 2020Co-Authors: Huajun Yang, Ping Jiang, Weinan Caiyang, Miaofang ZhouAbstract:With the improvement of the transmission efficiency, the Cassegrain antenna can be widely used in space optical communication. In this paper, the Bessel–Gaussian (BG) beam is used to avoid the central energy loss of a Cassegrain antenna system. The intensity distribution and the phase distribution of the BG beam passing through a Cassegrain antenna are theoretically derived and simulated. At a wavelength of 1550 nm, this method can theoretically improve the transmission efficiency to approach 100% under the situation in which the obscuration ratio is nonzero, and the transmission efficiency can reach more than 80% when obscuration ratio is in the range of from 0 to 0.1252 with $l=4$l=4. The effects of on-axial defocusing on the light field and the transmission efficiency are studied. The method proposed in this paper can remarkably improve the transmission efficiency of a Cassegrain antenna in a practical and uncomplicated approach.
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structure design of a conic lens pair for improving the transmission efficiency of a Cassegrain antenna
Applied Optics, 2019Co-Authors: Miaofang Zhou, Huajun Yang, Ping Jiang, Weinan CaiyangAbstract:Central energy loss is a critical factor decreasing the transmission efficiency of a Cassegrain antenna. In this paper, a pair of conic lenses are designed and set in front of a Cassegrain antenna to improve the transmission efficiency of the antenna instead of designing a complicated antenna structure. On the basis of the analysis, the optimized conic lens pair can theoretically improve the transmission efficiency up to 100% at a wavelength of 1550 nm under ideal conditions. After several practical factors are considered, such as the dispersion of the material, the transmissivity and chamfering of the conic lens, and the reflectivity of the mirrors composing the Cassegrain antenna, the conic lens pair can still increase the transmission efficiency of the Cassegrain antenna up to 92.37% at a wavelength of 1550 nm. Compared with designing a complicated antenna, the method proposed here provides a more practical approach to improve the transmission efficiency of a Cassegrain antenna.
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On-axial defocused characteristic analysis for Cassegrain antenna in optical communication
Optik, 2016Co-Authors: Minyin Yu, Huajun Yang, Ping Jiang, Yao Zhang(, Lu ChenAbstract:Abstract In order to reduce the chromatic aberration problem of the multiple wavelength, reflex Cassegrain antenna is widely used in space optical communication system. There are many external factors such as temperature and vibration that may cause defocusing in practice which has influence on Cassegrain antenna. That is to say, the primary mirror's and the secondary mirror's focus cannot be coincided, so it will bring impact greatly on transmission efficiency. This paper studies the effects on the transmission characteristics of the defocused Cassegrain antenna system. While defocused 2.5 cm, the transmission efficiency of Cassegrain antenna will decrease 80% of the initial efficiency. So it is very important to maintain optimum position for high transmission efficiency.
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Optimizing the secondary mirror structure parameters for Cassegrain antenna
Optik, 2015Co-Authors: Minyin Yu, Huajun Yang, Ping Jiang, Wensen HeAbstract:Abstract Cassegrain antenna is a very important type of optical antenna, which is widely used in space optical communications. However, the secondary mirror barrier may cause lower transmission efficiency in practice. This paper studies the factors affecting the transmission efficiency of the Cassegrain antenna system. Then, a series of optimum structure parameters are obtained, achieving a transmission efficiency of 91.6%. Therefore, this antenna can increase the transmission efficiency to a great extent in optical communication systems.
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An optimum analysis for Cassegrain optical antenna
Optik, 2015Co-Authors: Xiaojun Ma, Huajun Yang, Bing Wang, Ping Jiang, Mingyin Yu, Yuchun Huang, Shasha KeAbstract:Abstract In this paper, the energy loss caused by the secondary mirror of Cassegrain antenna has been discussed numerically. As the diameter of the secondary mirror is one-fifth of the primary mirror, the loss goes beyond 18.5%. Because of the alignment of the optical system being the significant factor, it influences the transmission quality of the optical antenna system. We analyze and numerically simulate how power attenuation ratio and gain of Cassegrain antenna vary with the antenna deflection, and measure the distance such that the central axis of the receiving antenna deviates from the z -axis in case of occurrence of off-axis space in the system. Finally, an optimum structure is proposed by trepanning the secondary mirror.
Guoquan Zhou - One of the best experts on this subject based on the ideXlab platform.
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power coupling of a two Cassegrain telescopes system in turbulent atmosphere in a slant path
Optics Express, 2007Co-Authors: Guoquan ZhouAbstract:The characteristics of dark hollow beams passing through a two-Cassegrain-telescopes system in turbulent atmosphere in a slant path have been investigated. The distribution of the average intensity at the receiver telescope and the efficiency of power coupling with respect to propagation distance with different parameters are derived and numerically calculated. These studies illuminate that the power of the dark hollow beams is concentrated on a narrow annular aperture at the source plane and its power coupling with a transmitter Cassegrain telescope can remain quite high. For short distance between the two Cassegrain telescopes, the normalized average intensity distribution at receiver plane holds shape similar to that at the source plane, and the two Cassegrain telescopes keep high efficiency of the power coupling. But with the increment in the propagation distance, the power of the dark hollow beams gradually converges to the central and the spot spreads. The central obscuration of the receiver telescope blocks more of the power; meanwhile more of the power moves out beyond the edge of the receiving aperture. Therefore, the efficiency of the power coupling decreases with the increment in the propagation distance. In addition, the relations between the efficiency of power coupling and wavelength of laser beams are also numerically calculated and discussed.
Xiegu Xu - One of the best experts on this subject based on the ideXlab platform.
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study on power coupling of annular vortex beam propagating through a two Cassegrain telescope optical system in turbulent atmosphere
Optics Express, 2013Co-Authors: Huiyun Wu, Shen Sheng, Zhisong Huang, Siqing Zhao, Hua Wang, Xiegu XuAbstract:As a new attractive application of the vortex beams, power coupling of annular vortex beam propagating through a two- Cassegrain-telescope optical system in turbulent atmosphere has been investigated. A typical model of annular vortex beam propagating through a two-Cassegrain-telescope optical system is established, the general analytical expression of vortex beams with limited apertures and the analytical formulas for the average intensity distribution at the receiver plane are derived. Under the H-V 5/7 turbulence model, the average intensity distribution at the receiver plane and power coupling efficiency of the optical system are numerically calculated, and the influences of the optical topological charge, the laser wavelength, the propagation path and the receiver apertures on the power coupling efficiency are analyzed. These studies reveal that the average intensity distribution at the receiver plane presents a central dark hollow profile, which is suitable for power coupling by the Cassegrain telescope receiver. In the optical system with optimized parameters, power coupling efficiency can keep in high values with the increase of the propagation distance. Under the atmospheric turbulent conditions, great advantages of vortex beam in power coupling of the two-Cassegrain-telescope optical system are shown in comparison with beam without vortex.
Huiyun Wu - One of the best experts on this subject based on the ideXlab platform.
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study on power coupling of annular vortex beam propagating through a two Cassegrain telescope optical system in turbulent atmosphere
Optics Express, 2013Co-Authors: Huiyun Wu, Shen Sheng, Zhisong Huang, Siqing Zhao, Hua Wang, Xiegu XuAbstract:As a new attractive application of the vortex beams, power coupling of annular vortex beam propagating through a two- Cassegrain-telescope optical system in turbulent atmosphere has been investigated. A typical model of annular vortex beam propagating through a two-Cassegrain-telescope optical system is established, the general analytical expression of vortex beams with limited apertures and the analytical formulas for the average intensity distribution at the receiver plane are derived. Under the H-V 5/7 turbulence model, the average intensity distribution at the receiver plane and power coupling efficiency of the optical system are numerically calculated, and the influences of the optical topological charge, the laser wavelength, the propagation path and the receiver apertures on the power coupling efficiency are analyzed. These studies reveal that the average intensity distribution at the receiver plane presents a central dark hollow profile, which is suitable for power coupling by the Cassegrain telescope receiver. In the optical system with optimized parameters, power coupling efficiency can keep in high values with the increase of the propagation distance. Under the atmospheric turbulent conditions, great advantages of vortex beam in power coupling of the two-Cassegrain-telescope optical system are shown in comparison with beam without vortex.
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A new method to improve power efficiencies of optical systems with Cassegrain-telescope receivers
Optics Communications, 2011Co-Authors: Huiyun Wu, Wuming Wu, Xiaojun Xu, Jinbao Chen, Yijun ZhaoAbstract:Abstract We presented a new method to improve power efficiencies of the optical systems with Cassegrain telescope receivers by using vortex sources with optimized parameters. A typical model of optical systems with Cassegrain telescope receivers was established and power losses in the optical system under the H-V 5/7 turbulence model were analyzed in detail. The calculating results showed that power efficiency of the optical system can be improved from 76.48% to 97.25%. A reduced-scaled experiment was carried out and the experimental results showed that power efficiency of the optical system can be improved from 71.89% to 90.60%.