ILS-past and present

Insight is provided into the evolution of VHF/UHF instrument landing system (ILS) equipment and the role of the US Civil Aeronautics and Federal Aviation Administrations in its development. The discussion covers the ILS localizer, glide slope (image arrays and nonimage arrays), marker beacon, reliability, and avionics     

Performance Analysis of a Dwell-Time Processor for Monopulse Beacon Radars

Performance of a monopulse air traffic control radar beacon system (ATCRBS) target data extractor is analyzed via an analytical approach. Results refer to a statistical analysis of the section of the receiver which associates replies sent by the desired aircraft during the antenna dwell-time. Some numerical results are reported which refer to the ATCRBS section to be devised in the discrete address beacon system (DABS).     

Deutsche Airbus flight test of Rosemount smart probe fordistributed air data systems

Deutsche Aerospace Airbus (division of DASA) and Rosemount Aerospace Inc. Jointly sponsored a flight test program to evaluate in-flight performance of distributed multifunction air data smart probes. The probes measure pitot pressure, static pressure, and angle of attack. The tests were conducted at the DLR Flight Test Center, near Braunschweig, Germany. Two smart probes were installed on the DLR VFW 614 ATTAS Flight Test Aircraft and tested between June of 1992 and January of 1993. Flight test results are presented together with suggested air data system architectures, including ARINC 738, that can be used with the distributed smart probe concept. New architectures are developed for future commercial aircraft. The smart probe concept offers several advantages including reduced weight and size, reduced number of line replaceable units (LRUs), and increased reliability. Overall cost of ownership is significantly lowered     

Correspondence [Errata to "Military digital avionics fiber-optic network design for maintainability and supportability", Sep 06]

Readers provide commentary about previous articles from the IEEE Aerospace and Electronic Systems Magazine.     

Eli Brookner [Exceptional Service Award]

Describes the career and professional achievements of Eli Brookner, who is the recipient of the IEEE Aerospace and Electronic Systems Society Exceptional Service Award.     

The Space Systems Technical Panel

The Space Systems Technical Panel of the IEEE Aerospace and Electronic Systems Society (AESS) was conceived in 2000 and established in 2001. The aims and main activities of the panel are highlighted together with an overview of the status of some ongoing key European space programs.     

William M. Brown [Obituary]

Recounts the life and career of William M. Brown, former Radar Editor of the IEEE Transactions on Aerospace and Electronic Systems, who passed away earlier this year.     

On the Perfomance of Air Traffic Control Radar Beacon System

The sidelobe suppression and improved sidelobe suppression mode performance of terminal and enroute air traffic control radar beacon systems using the existing antenna and a typical improved antenna in the presence of perfectly dielectric flat ground are investigated theoretically. Necessary analytical expressions for various quantities characterizing the system performance have been derived. A general purpose computer program has been developed for the computation and tabulation of these quantities as functions of the elevation angle of the observation point and for different combinations of heights of the directional and omnidirectional antennas of the beacon. Although the discussions given here apply to some specific antenna configurations, the theoretical method developed has more general application in evaluating quantitatively the performance of the beacon system in a given situation.     

基于GRU的仪表着陆系统故障预测方法研究

故障预测技术在保障仪表着陆系统的可靠运行、提高空管效能等方面具有重要应用价值。结合仪表着陆系统运行特征和实际运行维护工作,提出一种基于GRU 的仪表着陆系统故障预测方法。以航向信标为研究对象,在分析其监控参数与设备运行状态之间的关系后,将监控参数作为故障特征参数;根据监控参数时间步长、时变性特征显著的特点,采用GRU 预测监控参数的未来变化趋势;根据监控参数的隶属函数计算出参数未来时刻可能发生“故障”的概率,实现对航向信标故障的预测。结果表明：基于GRU 的预测方法的相对预测精度在95% 以上。     

The Significance of Letter Position in Word Recognition

Presents the summary of a PhD thesis on letter position in word recognition, which was written in 1976. The thesis was the source of the text used on the cover of the October 2006 issue of the IEEE Aerospace and Electronic Systems Magazine.     

Density and Temperature in Wind Tunnels Using Electron Beams

In a paper presented at the last meeting of the International Congress on Instrumentation in Aerospace Simulation Facilities, a method of measuring gas density by radiation scattering was presented. Since that time, the method has been further developed using scattering of 50-keV electrons and has been applied in a wind tunnel using air as a test gas. Test section temperature and density were in the neighborhood of 150°K and 6×10-8 g/cm3. In this application, accuracies better than 1.0 percent appear to be attainable, together with excellent spatial and temporal resolution. The application is described, and comprehensive design data are presented. In addition, the density measurements have been supplemented by measurements of the local rotational temperature, utilizing nitrogen molecular band radiation excited by a second electron beam. Comparisons between the density and temperature measurements and flow properties obtained by standard gas-dynamic calculations are made.     

Performance limits of track-to-track fusion versus centralized estimation: theory and application [sensor fusion]

Track-to-track fusion is an important part in distributed multisensor-multitarget tracking. The centralized and distributed tracking configurations were studied in (H.Chen et al., Proc. of SPIE Conf. on Signal and Data Processing of Small Targets, vol. 4048, 2000) using simulated air-to-air scenarios, and in (K.C. Chang, et al, IEEE Transact. on Aerospace and Electronic Systems, vol. 33, no. 4, pp. 1271-1276, 1997) with analytical results based on /spl alpha/-/spl beta/ filters. The current work generalizes the results in the latter to the cases with more than 2 sensors. As the number of sensors increases, the performance of the distributed tracker is shown to degrade compared with the centralized estimation even when the optimal track-to-track fusion is used. An approximate track-to-track fusion is presented and compared with the optimal track-to-track fusion with performance curves for various numbers of sensors. These performance curves can be used in designing a fusion system where certain trade-offs need to be considered. Finally, these results are compared with simulation results for a realistic air-to-air encounter scenario.     

Vehicle health management research for legacy and futureoperational environments

The Air Force will require the ability to diagnose and predict component failures in order to more effectively meet the requirements of the fast and agile Aerospace Expeditionary Force (AEF) and future space vehicles. This paper will cover topics relevant to vehicle health management for current and anticipated support environments. It reflects current projects underway at the Air Force Research Laboratory in the air vehicles and human effectiveness directorates. Specifically, the predictive failures and advanced diagnostics (PFAD) for legacy aircraft, passive aircraft status system (PASS), and the space operations vehicle integrated system (SOVIS) projects will be discussed     

弓网电弧辐射特性及对机场下滑信标的影响

为获得弓网电弧辐射特性及从理论上分析其对机场下滑信标的影响。选择典型电气化动车线路,首先基于CISPR16-1标准,利用电磁干扰接收机对电分相和普通点处的弓网电弧电磁辐射进行点频测试,获得了其在下滑信标台频谱内的辐射特性,然后基于电波传播理论,以电气化轨道平行跑道为例,分析了弓网电弧电磁辐射对飞机导航的影响。结果表明：电弧电磁辐射具有一定的随机特性,普通点处产生的电磁辐射场强小于电分相处;普通点的电磁辐射不会对飞机的导航产生干扰;当轨道距跑道中心的距离分别为700、120和60 m时,电分相拉弧点距下滑信标台天线的距离应分别小于3 291、546和249 m时才不会对飞机的导航产生干扰。本结果能够为轨道电气化和民用航空这两大工业体系在机场区域的电磁兼容性设计提供依据。     

基于FC-1394的空间载荷试验信息系统设计

IEEEl394是一种具有支持等时传输和异步传输的特点的高速串行数据总线,目前已在航天器载荷试验数据传输中得到良好应用,但在未来大型空间飞行器载荷试验信息传输的应用中仍存在重量功耗开销大、传输距离和速率有限等问题.光纤通道作为一种具有良好兼容性、可靠性高、低时延、传输距离远和传输速率高等优点的先进总线技术,可为上层协议提供通用的高速率数据传输通道.基于IEEEl394和光纤通道的基本特性,给出了一种适用于空间载荷试验信息系统的FC-1394桥接方案,并为基于IEEE1394和光纤通道协议映射的空间信息系统数据网络互连提供了一种解决方案.     

Open systems architecture solutions for military avionics testing

Raytheon makes extensive use of open systems architecture methods in developing special test equipment (STE) for testing military avionics equipment. Such use has resulted in significant cost and schedule savings in the development of production test equipment for radar and infrared systems. With open systems architectures, a test system can be assembled using COTS products. This brings economies of scale to test equipment, which is normally built in very low quantities. Therefore, the potential cost savings due to COTS usage is proportionately greater in STE than in the higher volume avionics systems that are tested. A second major benefit of using COTS products is that test system development schedule cycle time is greatly reduced. This paper describes the application of Open Systems Architectures (OSA) to avionics testing. The following major architectures are surveyed: VME bus, VXI bus, IEEE GPIB, IEEE 1149.1 JTAG test bus, 1553 Military Bus, Fibre Channel, and COTS Test Applications Software. We describe how the benefits of OSA have been extended at Raytheon into achieving vertical test commonalities. The flexibility of OSA can be exploited to provide an overall optimum test solution, taking all levels of test into account. For example, test systems can be tailored with COTS products to provide integrated methods for avionics tests at the module, unit, and system levels. Test systems can be configured to maximize the reuse of COTS hardware over all test levels. Test software can also be programmed to optimize such reuse over levels of test. Additional test verticality synergies derived from such OSA usage are described, including: test false alarm avoidance; test cones of tolerance optimization; and efficient test of field returns     

塔康仿真系统的设计

塔康是战术空中导航系统,能完成测距和测位的任务。塔康仿真器是具有塔康设备功能的计算机仿真系统,它可以代替塔康设备参与航空电子系统的综合试验,而且能取得很好的效果。本文在分析塔康工作原理的基础上,对塔康仿真器的硬件结构和软件设计做了较为详细的介绍,同时,对塔康信标的仿真也做了扼要的说明。     

电分相电弧对全向信标电磁辐射特性的分析

为了分析电气化铁路高速列车电分相电弧对机场全向信标（VOR）的影响,研究其电磁发射特性。利用电磁干扰接收机与频谱仪,分别以点频和扫频方式,对电气化铁路电分相点和普通点进行了大量辐射测试。分析测试数据的异方差性,改进回归分析方法,拟合出电弧在全向信标频段的幅频特性曲线,分析弓网电弧电磁辐射对机场全向信标的影响。结果表明：电分相电磁辐射是随机的,在电分相处比普通点大;现代电气化铁路高速列车经过电分相的测试数据异方差性比较明显,普通的最小二乘估计方法不适用;当电气化铁路电分相点与飞机距离小于4.944 km时,可能会对VOR信号产生影响。     

IEEE 1394: a growing computer connectivity standard for automatedtest

This paper describes the latest trends in the IEEE 1394 (“firewire^TM” or “iLink^TM”) standards and why it is becoming the connectivity standard of choice for automatic test applications. Why move to IEEE 1394, what are the possible risks with doing so, what are some of the myths associated with IEEE 1394 and a practical example of an automatic test application will all be presented with the prime emphasis on giving the latest information that will help you get IEEE 1394 integrated into your automatic test system     

Reply Correlation Test Analysis in Monopulse Beacon Radars

The statistical behavior of the position data furnished by single air traffic control radar beacon system (ATCRBS) reports is analyzed. Some statistical models are correspondingly derived in order to be employed for the performance evaluation of the dwell-time section of the ATCRBS monopulse receiver. The expression of the failure probability is derived for the range and azimuth tests performed by the association algorithms operating in the monopulse ATCRBS target data extractor. Some numerical results are reported referring to the evaluation of the above failure probabilities in different conditions.