The purpose of this research project was to design, implement, and evaluate a prototype underwater positioning system which extends the reach of the terrestrial Global Positioning System (GPS) underwater. The GPS does not function underwater because the high-frequency low-power signals used by the GPS are not able to penetrate more than several meters in water. The Underwater Global Positioning System (UGPS), presented in this work, provides underwater position data to an unlimited number of underwater assets, such as autonomous vehicles. The user requirements are discussed and a design is presented that incorporates a topside surface buoy (satellite) and a subsurface receiver. The satellite is responsible for receiving GPS data and relaying the data, via acoustic signals, to the subsurface receiver. The receiver calculates its position using the coded acoustic signals. The implementation of the prototype UGPS satellite and subsurface receiver are discussed in detail; the custom electronics, software, data acquisition systems and mechanical housings are described. The key operating characteristics of the UGPS are investigated both experimentally and through the analysis of a model describing the entire UGPS. Employing the prototype UGPS, a series of sea-trials were performed that provides essential design data for developing the next version of the system. The main characteristics that were experimentally investigated were: the long and short-range accuracy; the repeatability; and the resolution. The experimental data was also employed to confirm the UGPS model performance. The prototype system demonstrated the feasibility of the UGPS concept and showed that a position accuracy of 6.5m should be attainable for an unlimited number of underwater receivers operating within a one square kilometer workspace. The accuracy can be enhanced to sub-meter by employing more accurate GPS receivers in the satellites and using a sound velocity meter to measure the sound velocity profile of the acoustic workspace.

Rychlý vývoj v oblasti mobilní informatiky vyústil v nový, alternativní způsob mobilní komunikace, v němž mobilní uzly tvoří samoorganizující se bezdrátovou síť, jíž se říká mobilní síť ad hoc (Mobile Ad hoc Network, MANET). Specifické vlastnosti sítí MANET stavějí návrh síťového protokolu před řadu problémů na všech vrstvách protokolové sady . Příčinou jsou nepředvídatelné změny topologie a mobilní povaha těchto sítí. Nástrojem, který řeší problémy plynoucí z mobility uzlů, je predikce budoucích změn v topologii sítě. To má zásadní význam pro různé úlohy jako přesměrování. Tato disertační práce se zabývá dvěma metodami predikce mobility pro sítě MANET. První metoda se nazývá „predikce mobility s využitím virtuální mapy“ (mobility prediction using virtual map) a předpokládá, že každý uzel si dokáže vybudovat svou virtuální mapu v závislosti na svém umístění v průběhu času. Vyvinutý predikční algoritmus byl implementován do síťového simulátoru NS-2, aby jej bylo možné vyhodnotit. V této práci zkoumám stávající modely mobility a způsob, jakým v nich lze aplikovat tuto metodu predikce. Simulace sledují zlepšení výkonnosti, co se týče průměrného zpoždění na bázi end-to-end, poměru doručených paketů a propustnosti sítě. Navržený koncept predikce byl implementován pomocí směrovacího protokolu AODV(Ad Hoc On-Demand Distance Vector). Pro druhou metodu jsem vyvinula umělou neuronovou síť pro predikci pohybů v sítích MANET. Model pro predikci mobility vznikl na základě dat shromážděných ze vzorců umístění. K učení či trénování ANN byl využit bayesovský přístup. Ten byl implementován v softwaru pro trénování bayesovských neuronových sítí s názvem Model Manager. Nejlepším způsobem hodnocení závěrečného modelu je provedení predikcí a jejich srovnání s cílovými daty. Predikce vznikají na základě 50 vzorců jako vstupních proměnných. Dosažené výsledky prezentované s diskutované v práci se vyznačují zlepšením zásadních parametrů komunikační sítě, jako jsou propustnost, zpoždění, Poměr doručených paketů, až o 30% v porovnání s klasickým směrovacím protokolem AODV, kde není implementován predikční model.

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The Joint Advanced Missile Instrumentation (JAMI) Program’s main thrust has been the integration of Global Positioning System (GPS) tracking technology into the Department of Defense (DoD) Missile Test Ranges. This technology could be used for Time, Space, Position, and Information (TSPI), Flight Termination (FTS), or End Game Scoring purposes. However the Program’s main goal is to develop Proof-of-Concept components only. Transitioning Missile technology developed by the Government to Private Industry, so that it can be economically mass produced, has been quite a challenge. Traditionally, private industry has had to bid on proposals without much detailed information on how these components have been designed and fabricated. These unknown risks, Non-Recurring Engineering (NRE) and Missile Flight Qualification costs, routinely have significantly increased the price of these procurement contracts. In order so that the Fleet can economically utilize these components in the field, Cooperative Research and Development Agreements (CRADA) between the Government and Private Industry have been used to successfully transition Government developed technology to mass production. They can eliminate the NRE and flight qualification costs to provide for an economical and low risk method of providing the Fleet with the latest advances in GPS Tracking Technology. This paper will discuss how this is currently being accomplished in the development of a conformal wraparound instrumentation antenna for a five-inch diameter Missile Telemetry (TM) Section.

International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The accurate determination of test aircraft position and velocity is a very strong requirement in several certification and development flight test applications. This requirement often requires availability of test ranges properly instrumented with optical or radar tracking systems, precision time for data reduction and dependency on environmental and meteorological conditions. The capabilities of GPS (Global Positioning System) technology, in terms of data accuracy, speed of data availability and reduction of test operating cost, moved Bombardier Flight Test Center to make an investment and integrate a system utilizing GPS for extensive use in flight and ground test activity. Through the use of differential GPS (DGPS) procedures, Bombardier Flight Test Center was able to implement a complete system which could provide real-time data results to a very acceptable output rate and accuracy. Furthermore, the system was capable of providing post-processed data results which greatly exceeded required output rate and accuracy. Regardless of the type of aircraft testing conducted, the real-time or post-processed data could be generated for the same test. After conducting various types of testing, Bombardier Flight Test Center has accepted the DGPS as an acceptable and proper flight and ground test measurement tool for its various aircraft test platforms.

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / A system was developed using capabilities from the Range Applications Joint Program Office (RAJPO) GPS tracking system and the ACMI Interface System (ACINTS) to provide tracking data and visual cues to experimenters. The Mobile Advanced Range Data System (ARDS) Control System (MACS) outputs are used to provide research data in support of advanced project studies. Enhanced from a previous system, the MACS expands system capabilities to allow researchers to locate where Digital Terrain Elevation Data (DTED) is available for incorporation into a reference data base. The System Integration Group at Veda Incorporated has been supporting Wright Laboratories in the ground-based tracking and targeting arena since 1989 with the design, development, and integration of four generations of real-time, telemetry-based tracking aids. Commencing in Q3 1995, Veda began developing a mobile, transportable system based on the RAJPO GPS tracking system. The resulting system architecture takes advantage of the front end processor (FEP) used in the three previous generations of interface systems built for Wright Laboratories, thus maximizing hardware and software reuse. The FEP provides a computational interface between the GPS tracking system and the display (operator) system. The end product is a powerful, flexible, fully mobile testbed supporting RDT&E requirements for Wright Laboratories, as well as to other U.S. and foreign research organizations. The system is rapidly reconfigurable to accommodate ground-based tracking systems as well as GPS-based systems, and its capabilities can be extended to include support for mission planning tools, insertion of virtual participants such as DIS entities, and detailed post-mission analysis.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Edwards Flight Test Range is a part of 20,000 square miles of DOD airspace (R-2508). A hypersonic air vehicle traveling above Mach 3 can easily exceed that airspace within seconds. An Unpiloted Autonomous Vehicle can exceed the airspace when flying long duration missions. To satisfy the flight-test requirements of Hypersonic Air Vehicles and Unpiloted Autonomous Vehicles, additional airspace and extended test ranges are required. The Air Force Flight Test Center and Dryden Flight Research Center at Edwards Air Force Base, California have mutual goals to support these flight test programs. To meet these goals, the Extended Test Range Alliance was formed as an engineering and operations team to satisfy program requirements in the areas of telemetry, flight termination, ground communications, uplink command, and differential global positioning systems. This paper will discuss the resources and technical capabilities available through the Extended Test Range.

Epidemic obesity in the U.S. has prompted exploration of causal factors related to the built environment. Recent research has noted statistical associations between the spatial accessibility of retail food sources, such as supermarkets, convenience stores, and restaurants, and individual characteristics such as weight, socioeconomic status, and race/ethnicity. These studies typically use residential proximity or neighborhood density to food sources as the measure of accessibility. Assessing food environments in this manner, however, is very limiting. Since most people travel outside of their neighborhood on a daily basis, the retail food sources available to individuals residing in the same area could vary widely. This research developed new techniques for describing food accessibility or food environments based upon individuals’ activity and travel patterns, or their activity spaces. Researchers have previously used travel diaries to study activity and travel behavior, but these are burdensome for participants, and are prone to recall error and other inaccuracies. This study explored use of global positioning system (GPS) to identify participants' activity spaces, and employed a geographic information system (GIS) to assess the retail food sources located within these spaces. This produced ‘activity-based’ measures of individual retail food accessibility that do not rely on areal units, nor require travel diaries. Participants included 121 residents of a census tract in Lexington, Kentucky who agreed to carry GPS trackers for three workdays, and complete surveys regarding weight, socioeconomic and demographic characteristics, and diet and food purchasing habits. The types and relative frequencies of food locations within their activity spaces were compared to those within close proximity to the census tract. Dietary and food purchasing habits were subsequently analyzed in relation to activity-based food environment measures. The results of this study demonstrate substantial potential for misclassification bias in food accessibility research based on residential proximity or neighborhood density. Furthermore, this study observed statistically significant relationships between the new activity-based food accessibility measures and some personal characteristics and food-related behaviors. Despite some limitations, the techniques developed in this research show great potential for future research, which should be explored further in a variety of contexts.

International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / This paper examines the issues involved in replacing the current Range safety infrastructure with an autonomous range safety system based on GPS (Global Positioning Satellite) integrated navigation system solutions. Range safety is required in the first place because current launch vehicle navigation systems cannot meet a level of trust needed to determine if the mission is really under control and on course. Existing launch vehicle navigation is generally based on attitude and acceleration sensing instrumentation that are subject to drift, initialization errors and failures. Thus, a launch vehicle can easily be under the control of a seemingly operating navigation system, yet be steering the launch vehicle along an incorrect and dangerous flight path. Inertial-based navigation systems are good, but they cannot be trusted. The function of Range safety is to assure that untrustworthy navigation is backed up with a trusted system that has positive knowledge of the launch vehicle location, and the intelligence to decide when and where a launch vehicle must be destroyed. Combining inertial navigation, GPS derived position information and knowledge-based computer control has the potential to provide trusted and autonomous Range safety functions. The issues of autonomous Range safety are addressed in this paper.

Approved for public release; distribution is unlimited / Systems engineering is a vital element of systems acquisition, and yet, as a result of previous Department of Defense (DoD) and United States Air Force (USAF) policies and practices, many government systems engineers today lack the systems engineering/management skills required to successfully execute national security space programs. The purpose of this thesis is to study and understand common issues that have impacted the ability of the USAF to cost-effectively acquire satellite systems. The research performed here involves an analysis of the differences between the traditional DoD systems acquisition and the national security space systems acquisition processes and an investigation of previous national efforts to improve these processes. The analysis results, together with the findings from a review of successful and struggling space programs, are then used to discover trends that aid in the formulation of the recommendations in this thesis. Specifically, to improve USAF systems engineering management skills and thereby improve the national security space systems acquisition process, the role of the government systems engineer should be defined as one of risk management, and the government systems engineers should be trained, equipped, and tracked in order to efficiently perform systems engineering in support of the space systems acquisition process. Finally, the research findings will provide a foundation for future researchers to expand upon the recommendations and make steady progress toward improving DoD and USAF space systems engineering expertise. / Outstanding Thesis

Master of Science / Department of Biological and Agricultural Engineering / Stacy L. Hutchinson / Military training lands are a vital resource for national security and provide crucial habitat for a number of threatened and endangered species. Military land managers must manage the land in accordance with federal environmental policy and regulation, while simultaneously providing the lands needed for training military forces. Off road maneuver training can cause significant environmental damage including removal of vegetation, compaction of soils, increased erosion, loss of habitat, and degradation of the landscape to a point of not being useful for continued military training. Various techniques have been developed to help the military land managers determine a sustainable training level for the landscape. Many of these techniques have limitations in the spatial resolution of data collected and the ability to provide timely and accurate assessments of training disturbance. Advancements in GPS and GIS technology over the past two decades have shown the potential to fill this knowledge gap. In this study low cost civilian off the shelf (COTS) GPS devices were accuracy tested to determine their capability to provide reliable and accurate military vehicle locations during training (1.93 m CEP, 4.625m 2dRMS). The GPS data collected from COTS devices on three battalion training exercises at Fort Riley, KS were processed in a GIS and statistically analyzed to compare and contrast several off road maneuver metrics (speed, turning radius, distance traveled) by vehicle type tracked, and by platoon in order to determine if units or vehicle types could reliably explain the variation in these metrics. Lastly, a method of mapping the relative environmental disturbance was developed and mapped for the same data sets. Wheel sinkage was used as a measure of disturbance, it was calculated at each GPS point based on vehicle type and soil conditions then mapped in using a fishnet grid for Fort Riley, Kansas.