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1.
A simulation model of the adaptive optics of the German Vacuum Tower Telescope (VTT), Observatorio del Teide, Tenerife, is presented. The model uses modules from the integrated model of the Euro50 extremely large telescope, and includes submodels of a Shack-Hartmann wavefront sensor, a de-formable mirror, a tip-tilt mirror, high-voltage amplifier low-pass filters, a reconstructor and a controller. We investigate the impact on the closed loop bandwidth of changes in controller configuration and certain system parameters, such as low pass filter bandwidth and camera integration and readout time. Control strategies were tested on simple models before implementation on the full VTT model. Using the models, different control strategies are compared.  相似文献   
2.
自 1992年起云南天文台开始了在云南省西北部的天文选址。丽江高美古最终被选择作为未来中国地基天文光学观测的新址点。并且 ,在国家科技部 ,云南省政府 ,以及中科院的支持下 ,2m级天文望远镜项目在 2 0 0 0年 12月获得立项。在文中 ,我们简要的介绍了高美古台址的情况 ,并给出了 2 .4m望远镜的详细情况 ,以及其他相关情况。  相似文献   
3.
This paper describes the design of a star sensor based upon a high dynamic range CCD in order to reach an arcsec-level attitude determination in balloon-borne missions. A custom star identification software was developed and laboratory-tested on a prototype assembled using commercial components. A set of numerical simulations have been carried out to study the dependence on the pointing precision of the centroid position accuracy, the number of detected stars and the effect of the image focusing. Moreover, the role of the electronic noise and the discrete pixel structure on the light signals is identified by the analysis of numerical simulations. Laboratory tests confirm that the arcsec pointing accuracy with a 1 Hz update rate can be achieved with our combination of custom-developed software and selected hardware components.  相似文献   
4.
本文简要地介绍了云南天文台太阳射电快速记录系统PIN调制器的运用,描述了该器件的结构原理和性能检测,并给出了测试结果  相似文献   
5.
Radio observation is one of important methods in solar physics and space science. Sometimes, it is almost the sole approach to observe the physical processes such as the acceleration, emission, and propagation of non-thermal energetic particles, etc. So far, more than 100 solar radio telescopes have been built in the world, including solar radiometers, dynamic spectrometers, and radioheliographs. Some of them have been closed after the fulfillment of their primary scientific objectives, or for their malfunctions, and thus replaced by other advanced instruments. At the same time, based on some new technologies and scientific ideas, various kinds of new and much more complicated solar radio telescopes are being constructed by solar radio astronomers and space scientists, such as the American E-OVSA and the solar radio observing system under the framework of Chinese Meridian Project II, etc. When we plan to develop a new solar radio telescope, it is crucial to design the most suitable technical parameters, e.g., the observing frequency range and bandwidth, temporal resolution, frequency resolution, spatial resolution, polarization degree, and dynamic range. Then, how do we select a rational set of these parameters? The long-term observation and study revealed that a large strong solar radio burst is frequently composed of a series of small bursts with different time scales. Among them, the radio spike burst is the smallest one with the shortest lifetime, the narrowest bandwidth, and the smallest source region. Solar radio spikes are considered to be related to a single magnetic energy release process, and can be regarded as an elementary burst in solar flares. It is a basic requirement for the new solar radio telescope to observe and discriminate these solar radio spike bursts, even though the temporal and spatial scales of radio spike bursts actually vary with the observing frequency. This paper presents the scaling laws of the lifetime and bandwidth of solar radio spike bursts with respect to the observing frequency, which provide some constraints for the new solar radio telescopes, and help us to select the rational telescope parameters. Besides, we propose a spectrum-image combination mode as the best observation mode for the next-generation solar radio telescopes with high temporal, spectral, and spatial resolutions, which may have an important significance for revealing the physical essence of the various non-thermal processes in violent solar eruptions.  相似文献   
6.
The accurate observation of the microphysical structure of cloud and precipitation plays an important role in understanding the formation of clouds and precipitation. In-situ measurement using measuring instruments carried by meteorological balloons is an effective way to obtain the microphysical properties of cloud and precipitation particles, which is a supplementary means for aircraft to observe cloud and precipitation particles. This observation method plays a more and more important role in in-situ measurement. According to the difference of the working principle of the existing balloon-borne cloud and precipitation particles probes, the detectors can be divided into particle impact-sampling sensors, particle imaging sensors, light-scattering sensors, light intensity attenuation sensors and charge measurement sensors. The working principles, key technologies and main advantages and disadvantages of typical instruments were summarized, and their applications to detailed cloud structure acquisition, cloud remote sensing method establishment, cloud and precipitation physical process research and parameterization, and scientific observation of thunderstorm clouds were briefly introduced. Finally, the development trend of balloon-borne cloud precipitation particle detectors was prospected, which will provide reference for related technical research and equipment development.  相似文献   
7.
An introduction to the instrumonts to be used for solar radio observations in Beijing in Solar Cycle 23 is made in this paper. They are 10cm solar radio telescope which has been used for a long time,and 1.02.0GHz,2.63.8GHz and 5.27.6GHz spectrometers. The former two spectrometers has passed a test,showing high guality,and the 5.27.6GHz one will be in operation from 1999. It is believed that highl gualified data should be obtained in the next solar cycle.  相似文献   
8.
本文介绍了便携式人卫光电望远镜的主要性能特点,探讨了将其应用于狮子座流星暴观测的可能性。  相似文献   
9.
A technique to detect man-made interference in the visibility data of the Mauritius Radio Telescope (MRT) has been developed. This technique is based on the understanding that the interference is generally ‘spiky’ in nature and has Fourier components beyond the maximum frequency which can arise from the radio sky and can therefore be identified. We take the sum of magnitudes of visibilities on all the baselines measured at a given time to improve detectability. This is then high-pass filtered to get a time series from which the contribution of the sky is removed. Interference is detected in the high-pass data using an iterative scheme. In each iteration, interference with amplitudes beyond a certain threshold is detected. These points are then removed from the original time series and the resulting data are high-pass filtered and the process repeated. We have also studied the statistics of the strength, numbers, time of occurrence and duration of the interference at the MRT. The statistics indicate that most often the interference excision can be carried out while post-integrating the visibilities by giving a zero weight to the interference points.  相似文献   
10.
本文介绍月球射电探测仪的基本原理,通过讨论所使用的电偶极天线的特性,得到了月球地层上方不同频率及不同距地高度的天线方向图,为最终选择出最佳方案提供了参考.  相似文献   
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