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在研究和建立了多跑道障碍物限制面三维模型的基础上,基于G IS,开发了机场三维净空管理系统。该系统可按照相应标准自动生成单跑道特别是多跑道障碍物限制面、辅助进行净空管理,可极大地减少机场选址与规划中的超障物评定的工作量,显著提高净空管理效率,具有广阔的应用前景。 相似文献
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一、引言
穿越虹桥机场隧道的沉降监测遇到了如下几方面的问题:①在飞机未停航期间不能进入飞机跑道进行人工监测(凌晨1:30～5:00为停航时间);②飞机跑道表面不能有任何突起物;③对观测墩的安置应离开跑道中心线75 m;④设置在绿化带内的观测墩有限高要求(不得高于3.5 m),并要求有指示灯; 相似文献
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通过研究《民用机场飞行区技术标准》(MH,50001-2013)对进近面、过渡面、内水平面、锥形面、内进近面、内过渡面、复飞面和起飞爬升面组成的障碍物限制面定义的基础上,基于GIS技术,开发了机场三维净空管理系统.该系统可以按照相应的标准自动生成单跑道或双跑道障碍物限制面,辅助进行净空管理,极大地减少机场选址或者机场净空管理中障碍物评定的工作量,具有可视化、数字化、智能化的优点,在民航领域高速发展的今天具有广阔的应用前景. 相似文献
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CORS系统的雷电防御技术设计 总被引：1，自引：0，他引：1
根据CORS系统的组成情况,分析了雷电入侵CORS系统的方式以及对系统设备的危害,提出了CORS系统内部和外部设备的雷电防御技术设计,并结合西安市连续运行参考站防雷实例加以分析应用,仅供同行参考。 相似文献
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机场净空管理是机场运行指标的重要组成部分,做好机场净空管理确保飞行区的安全使用是机场当局主要工作之一。文中在对机场净空限制进行详细分析的基础上,建立单向跑道净空数学模型,并在数学模型的基础上建立单向跑道净空数字模型,再借助ArcScene进行三维显示。为进一步研究多根跑道综合机场净空限制模型,提高机场净空管理的准确度、精度和速度奠定基础。 相似文献
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Discussion of GPS Anti-Jam Technology 总被引：4，自引：0，他引：4
The Global Positioning System (GPS) satellita navigation aiding system, sometimes called NAVSTAR, has become a utility to
the military and many civilian areas. GPS, currently consisting of 24 satellites, is used by the military for navigation,
precision weapons delivery, and the future digital battlefield. In the civilian sector, GPS is widely used as the primary
or secondary aid for land, water, and air navigation; as a surveying aid; as a vehicle location system; and as a precision
time standard for cellular and ATM sites. In the aviation community, GPS is becoming an integral part of the WAAS (Wide Area
Augmentation System) and the LAAS (Local Area Augmentation System) for en route navigation in North America and Category II
and III precision approach, and for surface navigation. The vulnerability of GPS have become the vulnerabilities of WAAS and
LAAS, and require consideration of interference mittigation techniques. ? 1999 John Wiley & Sons, Inc. 相似文献
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设计了LAAS（GPS局域增强系统）参考站故障检测和排除方法；推导了多参考站伪距改正数误差及限值的计算公式。在任意B值排除方法的基础上提出了最大B值排除方法，通过分析得到，该方法有较好的完善性和连续性性能。 相似文献
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Certain GPS receivers exhibit a power-induced measurement error when the input signal power exceeds a certain threshold that is a function of the receiver architecture. The characterization of this error is important in the case of airport pseudolites (APLs) due to receiver saturation at ranges close to the transmission antenna. This paper details an effort using laboratory test to characterize the power-induced measurement error in NovAtel Millennium and Beeline receivers that are widely used for APL development. The results from the laboratory tests show that this effect can lead to errors as large as 3 m on pseudorange measurement for the dynamic range typical for APLs. The carrier-phase error however is seen to be limited to 5 cm. On the verification and characterization of the error, a cost-effective mitigation technique for LAAS is proposed. A solution for the ground subsystem is sought by employing power-control measures to limit the amount of APL power that LGF GPS/APL receivers are exposed to. In order to keep the integration cost low, the solution for the airborne subsystem does not involve hardware modifications or additions, but rather relies on the transition to a differential carrier-phase positioning algorithm prior to the onset of the power-induced error along the approach path. The proposed architecture was flight-tested to verify successful mitigation of the power-induced error on both the ground and air, and the results from these tests are presented in the paper. 相似文献
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Since the traditional Maximum Likelihood-based range domain multiple reference consistency check (MRCC) has limitations in
satisfying the integrity requirement of CAT II/III for civil aviation, a Kalman filter-based position domain method has been
developed for fault detection and exclusion in the Local Area Augmentation System MRCC process. The position domain method
developed in this paper seeks to address the limitations of range domain-based MRCC by focusing not only on improving the
performance of the fault detection but also on the integrity risk requirement for MRCC. In addition, the issue of the stability
of the Kalman filter in relation to the position domain approach is considered. GPS range corrections from multiple reference
receivers are fused by the adaptive Kalman filter at the master station for detecting and excluding the single reference receiver’
failure. The performance of the developed Kalman filter-based MRCC has been compared with the traditional method using experimental
data. The results reveal that the vertical protection level is slightly better in the traditional method compared with the
developed Kalman filter-based approach under the fault-free case. However, the availability can be improved to over 97% in
the proposed method relative to the traditional method under the single-fault case. Furthermore, the fault-tolerant positioning
result with an accuracy improvement of more than 32% can be achieved even if different fault types are considered under the
single-fault case. In particular, the algorithm can be a candidate option as an augmentable complement for the traditional
MRCC and can be implemented in a master station element of the LAAS integrity monitoring architecture. 相似文献
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海岸线是指平均大潮高潮时水陆分界的痕迹线.在实际操作中,如有一线海堤以该海堤为海岸线,如无一线海堤则需根据近期平均大潮高潮位确定海岸线.海岸线修测自调查中间线起始点向两侧各50 km的海岸线进行岸线走向测量,文章分析了勘界工作方法与内容,叙述了海岸线修测的基本内容,进行了海岸线稳定性评估,对海域勘界有实际意义. 相似文献
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约束秩亏间接平差模型的法方程系数矩阵为分块矩阵,其左上角的子块矩阵秩亏,因此无法直接计算分块矩阵的凯利逆矩阵.利用矩阵运算,构建一个能直接求凯利逆的分块矩阵,进而推算出约束秩亏间接平差模型法方程系数矩阵的凯利逆的直接显性表达式.提出将约束条件看作虚拟观测,和原有的秩亏间接平差模型组合成新的误差方程,再和约束条件组成约束... 相似文献
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针对GEO卫星切向轨道分量与双差模糊度强相关的问题,对经典双差动力法进行了改进,提出联合使用载波相位和相位平滑伪距实现北斗系统精密定轨,并从理论上分析了以上处理策略的可行性及对模糊度固定的影响,然后结合北斗系统精密定轨特点,推导给出了利用QIF方法实现北斗卫星双差模糊度固定的基本原理,实测数据分析表明:联合载波相位和相位平滑伪距,既可降低相关性,又可兼顾精度,定轨效果优于经典双差动力法;利用QIF方法能够取得一定的模糊度固定效果,但受观测条件限制,北斗卫星双差模糊度固定成功率整体不高,双差模糊度固定之后对轨道的改进作用有限。 相似文献