ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The use of Ethernet and Internet Protocol (IP) networking technologies in flight test instrumentation and telemetry systems is rapidly increasing, driven by the ubiquity, scalability, and flexibility of networking technologies. Networks first made a positive impact in ground station infrastructure and have recently been emerging in test article data acquisition infrastructure in programs such as the A380, 787, P-8A, and Future Combat Systems. The next logical step is to provide a two-way network telemetry link to fully extend the flexibility of the network between the test articles and ground station. The United States Department of Defense (DoD) integrated Network-Enhanced Telemetry (iNET) program is currently working to build a standardized network telemetry link for exactly this purpose. When developing a network telemetry link, the limited availability of telemetry spectrum must be considered and thus it is critical to choose system-level approaches to maximize the throughput achieved from the link. This paper first presents the statistics of the network data that would typically use this link based on empirical data from current network-based flight test instrumentation systems. Several approaches to using a network telemetry link are then presented. Predicted achievable throughputs of each approach are presented that are derived from the statistics of the empirical test data. Based on this, the paper presents recommendations for building systems using network telemetry links.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper describes key points in the field of Galileo application abroad spacecraft and normal vehicles. On the basis of ephemeris of Galileo constellation, the mathematic model and procession are given in high dynamic signal environment, the digital simulation is also completed, the results are statistics and analyzed and presented. On the topic of navigation satellite constellation orbit and visibility, the paper presents the Galileo frame system, time system, navigation satellite orbit elements, constellation structure, and GDOP calculation. The users include low dynamic as well as high dynamic spacecraft. The analysis for relevant GPS is also showed. About the navigation signal structure, main points are Galileo system working frequency, including E5, E6 and L1 frequency spans, the modulation and navigation data, ets. At the same time, this paper compares Galileo with GPS. On the aspect of signal communication link, Dopplar frequency shift and power level calculation are present as well as compare with GPS system.

International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper describes the design considerations and methodology applied to solve the practical problems posed in the creation of a high bit rate telemetry relay system and specifically the techniques implemented to enhance signal to noise performance under adverse operational conditions.

International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Methods to improve reception during multipath fading of telemetry data received aboard ships participating in missile exercises include various diversity techniques. Among these techniques are polarization, angle, height, and frequency diversity. In this paper, a two-ray multipath model is used to investigate the various techniques and determine the merits of each. Possible ways of implementing the promising ones are discussed.

International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The VHF air/ground data link of CAAC is introduced in detail. This paper proposes a solution of VHF air/ground data link system, which exchanges downlink messages and uplink messages in data link information processing networks. The following topics are covered in this paper: components of VHF data link; data processing and design about VHF data link Gateway system; the application of VHF air/ground data link in airlines.

In this thesis we derive some basic properties of graphs G embedded in a surface determining a link diagram D(G), having a specified number μ(D(G)) of components. ( The relationship between the graph and the link diagram comes from the tangle which replaces each edge of the graph). Firstly, we prove that μ (D(G)) ≤ f (G) + 2g, where f (G) is the number of faces in the embedding of G and g is the genus of the surface. Then we focus on the extremal case, where μ (D(G)) = f (G) + 2g. We note that μ (D(G)) does not change when undergoing graph Reidemeister moves or embedded ∆ ↔ Y exchanges. It is also useful that μ(D(G)) changes only very slightly when an edge is added to the graph. We finish with some observations on other possible values of μ(D(G)). We comment on two cases: when μ = 1, and the Petersen and Heawood families of graphs. These two families are obtained from K6 and K7 respectively by using ∆ ↔ Y exchanges.

Today, different types of cellular networks are actively working on the radio links. For instance, the Global System for Mobile Communication (GSM) is being used in nearly two hundred countries and currently it has around two and half billion users all over the world. Universal Mobile Telecommunication System (UMTS) is currently deployed in many countries and it is providing increased data rates, coverage and mobility as compared to GSM. Wireless Local Area Networks (WLAN) are very famous when we have a small area and none real time services. Worldwide Interoperability for Microwave Access (WiMAX) is a new technology and it is in deployment phase. In all these cellular technologies, we have very limited recourses and we have to make best use of them by proper management. Radio Resource Management (RRM) is a control mechanism for the overall system which is being used to manage radio resources in the air interface inside a cellular network. The main objective is to utilize the available spectral resources as efficiently as possible. Our aim is to use them in the best possible way to maximize the performance and spectral efficiency in such a way that we have maximum number of users in our network and Quality of Service (QoS) is up to the mark. In a cellular communication system, a service area or a geographical region is divided into a number of cells and each cell is served by an infrastructure element called the base station which works through a radio interface. The frequency license fees, real estate, distribution network and maintenance are the issues which dominates the cost for deploying a cellular network. Management of radio related resources is a critical design component in cellular communications. In RRM, we control parameters like Radio Frequency (RF) planning, link budgeting, modulation schemes, channel access schemes etc. RF planning includes cell planning, coverage of the network and capacity of the network. Our main focus in this thesis will be on cell planning and link budgeting and we will discuss them in context of a WiMAX network.

This study has examined the relationship between corporate governance structures and the performance of a sample of companies listed on the Malaysian Stock Exchange in the post-Asian financial crisis period beginning 2001 and ending in 2003. The sample was selected to provide matched-pairs of government linked companies (GLCs) and non-government linked companies (NGLCs), as it was anticipated that these groups would have different governance structures and that these differences might impinge on the association being studied. The empirical results indicate that there were eight statistically significant differences between the corporate governance structures of GLCs and NGLCs, thus supporting the contention that it would be useful to examine the association between corporate governance structures and performance for these two distinct groups separately. Accordingly, univariate and multivariate tests were performed on three samples: (i) GLCs; (ii) NGLCs and (iii) a combination of these referred to as All Companies. The multivariate tests were performed both on the dataset collected from published sources and this data transformed using the Van Der Waerden approach. Although tests for conformity suggested no significant statistical problems with the original data-set for multivariate analysis, it was hoped that the transformation would provide better models for explaining the relationship between corporate governance variables and performance. The multivariate analyses on both the standard and transformed data-set found no empirical evidence of a consistent relationship between corporate governance structures and performance measured by return on assets and return on equity in GLCs, NGLCs or the combined sample over the period. Statistically significant relationships were found across the groupings and for different performance measures but were not sustained across all years. The implications for corporate governance research of these inconsistent results across different measures of performance and different samples across the three year period is that empirical research may reach conclusions based on statistically significant results at a point in time that are only relevant for this historic context and may not persist. The results also indicate that, despite the eight differences in governance structures of GLCs and NGLCs, the observed differences in the performance could not be explained by their governance structures. This finding supports the view that these structures provide appropriate monitoring on company’s management rather than improving performance. These findings are consistent with the ambivalent position on the relationship between performance and corporate governance variables observed by the literature which exhibits conflicting arguments about the direction of relationships and empirical results that are extremely variable. This study also found that the relatively poor performance of GLCs in Malaysia which has been associated with government influence on the board structures such as the appointment of a bumiputra as director (BUM), a senior government officer as director (SGO) and a politician as director (POL) were basically unfounded because these variables have no statistically significant adverse impact on performance.

The work presented in this thesis describes the development of a novel strategy for the steady state tip position control of a single link flexible robot arm. Control is based upon a master/slave relationship. Arm trajectory is defined by through 'master' positioning head which moves a laser through a programmed path. Tip position is detected by an optical system which produces an error signal proportional to the displacement of the tip from the demand laser spot position. The error signal and its derivative form inputs to the arm 'slave' controller so enabling direct tip control with simultaneous correction for arm bending. Trajectory definition is not model-based as it is defined optically through movement of the positioning head alone. A critical investigation of vacuum tube and solid state sensing methods is undertaken leading to the development of a photodiode quadrant detector beam tracking system. The effect of varying the incident light parameters on the beam tracker performance are examined from which the optimum illumination characteristics are determined. Operational testing of the system on a dual-axis prototype robot using the purpose-built beam tracker has shown that successful steady state tip control can be achieved through a PD based slave controller. Errors of less than 0.05 mm and settling times of 0.2 s are obtained. These results compare favourably with those for the model-based tip position correction strategies where tracking errors of ± 0.6 mm are recorded.

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