The Super Dual Auroral Radar Network (SuperDARN) is a global network of coherent high frequency (HF) radars located in the polar, high- and mid-latitudes of both the Northern and Southern hemispheres. This thesis deals with close-range SuperDARN echoes (oblique HF backscatter from the lower part of the ionosphere). The aim of this thesis is to shed light on the origin of these echoes. Previous studies have been content to propose explanations for the origin of these echoes without thorough checking of the proposed mechanisms against constraints available from various radars and other important information. For the purpose of clarifying the situation, a chain of SuperDARN radars in the Northern and Southern hemispheres and several years of daily statistics have been used. This has allowed for several findings. Notably, the close-range SuperDARN echoes show diurnal and seasonal variations and their properties with respect to signal-to-noise-ratio, Doppler velocity and Doppler width vary. Three distinct populations of close-range HF backscatter have been established: (1) a morning population (0400-0700 LT), (2) a midday summer population (0800-1300 LT) and (3) a pre-midnight (2100-2300 LT) population. The morning population is associated with meteor trails which are observed to be peaking near local dawn as expected, and already suggested by previous research. High latitude SuperDARN radars also had echoes (pre-midnight population) with higher Doppler velocities than the others yet the Doppler velocities are smaller than that expected from auroral E region echoes. Given the time and location of this population of echoes, it has been concluded that they are a special class of high latitude E region echoes at high aspect angle which have been termed ``high aspect irregularity region" echoes in the past. Lastly, the midday summer population was found to be too high for polar mesosphere summer echoes and too early for plasma instabilities. It is proposed that these SuperDARN echoes are produced either from contribution from meteors trails or by neutral turbulence which is suspected (from other work) to be present near 100 km. The properties of the midday summer population resembles those of meteor trails as they have the same power, and the same altitude and have high summer occurrence as expected for meteors. Their late morning occurrence could be due to particular look direction of individual radars which may change the occurrence statistics in the presence of meteor showers. With respect to neutral turbulence, the drift of the midday summer population is similar to that of neutral wind.

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International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / The Range Commanders Council "Flight Termination Systems Commonality Standard," RCC 319-92, has been written with the noble goal of providing "common design, test, and documentation requirements for Flight Termination Systems (FTS)." As is often the case with standards of any kind, the devil is in the details! The Army TACMS (ATACMS) Block II Flight Termination/Telemetry System design has been significantly affected by the constraints imposed by RCC 319-92 as well as by Lockheed Martin Vought Systems customers' interpretations of those constraints and requirements. Important system elements are discussed along with some of the engineering decisions made to achieve compliance and the rationale behind those decisions. It is hoped that this monograph will acquaint potential users of RCC 319-92 with some of the issues involved in achieving compliance.

International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Strategic Arms Reduction Treaty (START) introduces an important new element into the Mission planning and operation processes of the Western Range and its users. In the past, safe and successful completion of a ballistic or space operation was the primary mission of the Range. Under START, the Western Range has the added responsibility of playing a major role in the verification process necessary for a safe reduction of the world's ballistic nuclear weapons. This paper describes the impact of the Treaty on both the Western Range and its users while outlining how the Range has adapted to meet the challenges introduced by the Treaty.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The telemetry system has been used in many important fields. Generally speaking, it’s easy to judge whether the system operation is successful or not. But when it is running normally, it is not easy to evaluate the medium state (between success and fail) of the telemetry system, likes a man’s spirit state. In this paper, a method with fuzzy theory is brought forward to evaluate the “Spirit State” of the telemetry system. This method can be used to evaluate the telemetry system, or to evaluate other important system states. By this method, the estimation to the mission will be very exact and reliable.

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / This paper summarize range error caused by instability of transmission characteristics and change of signal frequency and amplitude. On the basis of transmission system's modulation-demodulation combined characteristic, amplitude-frequency characteristics even symmetry, phase-frequency characteristics odd symmetry, phase orthogonality of demodulator, author analyses influence of factors on range accuracy. And formulas of phase of ranging tone are derived. Using these formulas, the many factors having influence on drift range error may be calculated, and range accuracy can be improved. Above conclusion has been testfied and applied in TT&C system for years.

International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / Telemetry receiving sites at missile test ranges almost always use polarization diversity to maximize the quality of the telemetry signals collected from missiles during developmental tests. If the sites are operating optimally, their sensitivity should be independent of received polarization. In this paper a technique to test the sensitivity of each receiving site is presented that involves radiating from a central location with selectable polarization and precise power level. Results of testing five telemetry sites are presented and compared with performance predicted through link analysis using site G/T and location information.

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / Lower operating budgets and reduced personnel are causing the operators of test ranges to consolidate their assets and seek ways to maximize their utilization. This paper presents the versatile approach used by the NASA Dryden Flight Test Facility located at Edwards Air Force Base to monitor, control and operate five of its diversely located telemetry systems from a central control room. It describes a new generation of multi-purpose antenna controllers which are currently being installed as part of this NASA upgrade program.

International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / This paper describes a new mobile self contained telemetry station designed for field testing of air-to-ground weapons. The telemetry station makes creative use of existing equipment and incorporates a unique dual axis tracking system to provide complete coverage of most missions.

International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Vessel Traffic Management System is a cooperative effort of the Naval Undersea Warfare Center and the Naval Air Warfare Center Aircraft Division, funded by the OSD's Test Technology Development and Demonstration Program. The project is establishing the capability to acquire ship tracking information from numerous sources (GPS and radar target extractors), and combine them into a comprehensive, integrated view of the range safety target area. The consolidated tracking information will be transmitted to range safety vessel personnel and presented on portable display systems to aid in clearing the surveillance area of unauthorized vessels. The communications module is media independent in that positional and image data can be routed via RF modem, cellular phone, Intranet or Internet, singly or in any combination. The software systems for data acquisition, display and control are also platform independent, with the system under development operating under WindowsNT and Windows95. Additionally, the use of Java and VRML tools permits a user to display data (including three dimensional presentations of the data) without requiring the applications software. This system has numerous applications including range safety, commercial vessel traffic management, port authority and services monitoring, and oceanographic data gathering.