DEVELOPMENT OF AN OPTIMIZED ANTENNA AND OTHER ENHANCEMENTS OF A SPECTROMETER FOR THE STUDY OF OZONE IN THE MESOSPHERE
DEVELOPMENT OF AN OPTIMIZED ANTENNA AND OTHER ENHANCEMENTS OF A SPECTROMETER FOR THE STUDY OF OZONE IN THE MESOSPHERE
复制标题
开发用于研究中间层臭氧的优化天线和光谱仪的其他增强功能
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
A. Rogers
中科院分区：
文献类型：
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作者：
S. Tenneti;A. Rogers
该项目的目标是优化Haystack上测量中间层臭氧量的光谱仪的性能。这就需要寻找和测试紧凑、廉价的低噪声块转换器（LNB），这些转换器可以在电磁频谱的X波段高效工作。测试了各种设备，如Fortec FSKUVN 0.2 dB、Invacom SNF-031 0.3 dB喇叭、Invacom SNF-031 0.3 dB C120法兰和Smart 0.1 dB。软件被用来估计作为方位角和仰角的函数的“天空噪声”，并反过来被用来计算天线响应。许多校准技术用于获得噪声系数的准确值，例如使用各种吸收器来测量“Y因子”、液氮校准以及使用周期性打开和关闭的荧光灯进行校准。还测试了一些可能的解决方案，以减少从地面的溢出，并进一步优化天线性能。引言观察11.072 GHz臭氧线的设置主要包括一个“直接电视”偏置抛物面碟和一个LNB远离碟的距离等于其焦距，并在一个角度等于其偏移角。对于Winegard DS-4047，焦距为10.6”，偏移角为24度。反射镜位于碟形天线的中心，用于对准，天线波束以8度仰角接近碟形天线。抛物线：21 = y2/（4 f）
The goal of this project was to optimize the performance of a spectrometer at Haystack that measures the amount of ozone in the mesosphere. This required searching and testing for compact, inexpensive low noise block converters (LNBs) that can perform efficiently in the X-band of the electromagnetic spectrum. Various devices were tested such as the Fortec FSKUVN 0.2 dB, Invacom SNF-031 0.3 dB Horn, Invacom SNF-031 0.3 dB C120 flange, and the Smart 0.1 dB. Software was used to estimate the “sky noise” as a function of azimuth and elevation, and in turn was used to calculate the antenna response. Numerous calibration techniques were used to obtain accurate values for the noise figure, such as the use of various absorbers to measure the “Y-factor”, liquid nitrogen calibration, and also calibration with a fluorescent lamp that periodically turns on and off. Some possible solutions to reduce spillover from the ground and further optimize the antenna performance, were also tested. INTRODUCTION The setup to observe the ozone line of 11.072 GHz consists mainly of a “Direct TV” offset parabolic dish and an LNB away from the dish at a distance equal to its focal distance and looking up at an angle equal to its offset angle. For the Winegard DS-4047, the focal distance is 10.6” and the offset angle is 24 degrees. A mirror is located at the center of the dish for alignment, and the antenna beam approaches the dish at 8 degrees elevation. Parabola: 21 = y2/ (4 f)