Kegel, Thomas; Lipe, Bruce; Edwards Air Force Base (International Foundation for Telemetering, 1999-10)
      This paper describes the Real-Time/Post-Flight Processing System (RT/PFP) developed under the Air Force Flight Test Center (AFFTC) Advanced Data Acquisition and Processing Systems (ADAPS) development program. The RT/PFP is currently being deployed at all Range Division Mission Control Facilities as the principal Range Division telemetry processing system. This paper provides an overview of the RT/PFP system, its current capabilities, and future enhancements being developed. The RT/PFP is currently used to support the F-22 flight test program, and to provide telemetry processing support for the AFFTC Range Safety Office. The RT/PFP is also used in a mobile configuration to support the Advanced Fighter Technology Integration program.

      Terziev, George; Feher, Kamilo; University of California; Digcom, Inc. (International Foundation for Telemetering, 1999-10)
      The performance of novel experimental blind equalizers suitable for a large class of applications including telemetry systems and other wireless applications is described. Experimental hardware research of these adaptive patent pending Feher Equalizers (FE) confirms computer simulated data [1]. A two-ray RF selective faded telemetry channel has been simulated. A dynamically changing channel environment with a selective fade rate in the 1Hz to 50Hz range has been constructed by laboratory hardware. The Test and Evaluation (T&E) setup had RF frequency selective dynamic notch depth variations in the Power Spectral Density (PSD) within the band of the signal of up to 15dB. As an illustrative example of the adaptive equalizer capability we used a 1Mb/s rate Feher patented FQPSK [1] Commercially Of The Shelf (COTS) product. Both hardware experimental results as well as simulation indicate substantial performance improvement with the utilization of the FE. It is demonstrated that the FE improves for a large class of frequency selective faded systems the Bit Error Rate(BER) from 10^-2 to 10^-6. Similar performance improvements are presented for the Block Error Rate (BLER).
    • Advanced Data Acquisition and Processing System (ADAPS) – The Current State of the System

      Hafner, F. W. (Bill); Edwards Air Force Base (International Foundation for Telemetering, 1999-10)
      The technology growth in the Aerospace industry, as manifested and embodied in the current fighter technology, presents many challenges in the area of flight test and data processing. Past papers have delineated the concepts brought to bear in the design and implementation of the AFFTC’s latest generation of telemetry data systems in the Advanced Data Acquisition and Processing System (ADAPS) program. The current deployed system incorporates the planned approach of commercial-off-the-shelf (COTS) and government-off-the-shelf (GOTS) elements as basic to the system solution. The state of the program has advanced through full development, delivery and performance testing. The system is currently deployed in support of flight testing at Edwards AFB. This paper will present the status of the program.

      Luten, Robert H.; Diekmann, Vernon; Luten Data Systems; Tybrin Corp. (International Foundation for Telemetering, 1999-10)
      A typical telemetry system for aircraft flight-testing transmits one or several data streams to the ground for real-time display and analysis, and also records the same stream onboard for later playback. During test operations, only a fraction of the available data is used at any given time for real-time display or analysis. More efficient use of the RF channel could be realized if only the data needed for the current test point is transmitted, rather than the entirety of the data. Intelligent selection of a subset of the data stream can provide large reductions in the required telemetry downlink bandwidth. As one of the Advanced Range Telemetry (ARTM) On-Board Data Management (OBDM) initiatives, a prototype on-board data selection subsystem is being developed and demonstrated. The demonstration utilizes COTS telemetry workstations to the maximum extent possible and includes “plug-in” data requestor, selection, and server components to implement the added DML functionality. A significant objective of the OBDM/DML project will be to validate RF channel models to help minimize the amount of flight-testing necessary to validate the DML concept. This paper will discuss the OBDM/DML architecture, integration of several custom components with the COTS portions of the ARTM “test bench”, and the current status of the OBDM/DML development and test program.

      Claffey, Douglas J.; Analytical Graphics, Inc. (International Foundation for Telemetering, 1999-10)
      Advances in high-level architectures in both hardware and software now allow 3D software modeling and interactive simulation to be done from the desktop computer. This paper will address the increasing demand for 3D software modeling and simulation applications throughout the aerospace industry, what kinds of tools are currently available, how operational data is being used in real-world applications, and how to couple real-time data with terrain models and simulation tools to model and analyze operational environments. The following specific areas will be addressed: · The creation of real-world environments by merging virtual objects and ground data with interactive simulation and advanced graphics. · Recent advances in software modeling and simulation tools, which mirror general industry trends. · The ongoing effort to establish standards for modeling and simulation applications throughout the aerospace industry. · Examples of applications using high-level architecture-enabling technology like the visual display of detailed terrain data, drag-and-drop imagery, the enhancement of graphical performance without compromising the quality of rendered data, and expanded support for raster file format images.

      Schmidt, Allen; Computer Sciences Corporation (International Foundation for Telemetering, 1999-10)
      A broad class of Electro-Optical (E-O) sensors are continually being improved and/or developed for aircraft to assist in performance of such tasks as surveillance, target acquisition, target designation, and weapons delivery. These E-O sensors possess a variety of Electro-Optical links that encompass the spectral region of 0.4 to 14 micrometers. The Radiometric Lab at Edwards Air Force base is tasked to provide instrumentation support for projects that develop, test, and evaluate ground and airborne E-O systems/sensors. The heart of the labs support capability is the Radiometric Analysis and Measurement System (RAMS) and is contained within an all-terrain van. A variety of sub-systems exist within the van to meet support requirements. These include an 8 to 12 micron infrared (IR) imaging system, 4 to 14 micron spectral radiometer, 380 to 1068 nanometer spectral radiometer, 400 to 1800 nanometer imaging camera, 1.064 nd:YAG laser, off-axis collimator with IR and visible light sources, and a weather station. This paper describes the system, its capabilities and limitations, and its application in aircraft sensor evaluation.

      Cronauer, Tom; Cronk, Steve; Lipe, Bruce; Air Force Flight Test Center Range Division (International Foundation for Telemetering, 1999-10)
      The Range Division of the 412th Test Wing has recently had to incorporate high power RF transmission, remote monitoring and remote operation of systems to support the new Range Safety function incorporated within the Range. The sub-systems that make-up the Range Safety System are: Command Transmitter System (CTS) Command Panel System (CPS) Instantaneous Impact Prediction (IIP) (modified TECCS) Range Safety Data Display (ADAPS) Range Safety Data Recording (RaSDR) Flight Termination Test Set Being aware of the increasing importance of cost associated with ground and flight testing, the Range has structured its systems around Commercial Off The Shelf (COTS) hardware and software and remote operations where ever and when ever possible. This paper will outline the Ranges approach to Range safety addressing the rational behind the system design and making the customer happy. We will also discuss typical operations and how the Range maintains redundancy and RCC compliance.

      Ward, John M.; Edwards Air Force Base (International Foundation for Telemetering, 1999-10)
      Increasingly, military managers are requiring better and more efficient use of Special Use Airspace (SUA) and Military Operating Areas (MOA). To date, there has been no automated method for determining airspace utilization within the R-2508 Complex. This paper describes the development of a computer based airspace management tool called Airspace Utilization Reporting System (AURS). AURS receives aircraft beacon radar data from an air traffic control automation system used within the R-2508 Complex. The system processes this data in a customized Oracle database format and responds to query requests, making any information about aircraft activities and airspace utilization available to the user. AURS operates continuously 24 hours per day, seven days per week. The system provides a tool for near complete analysis of all transponder equipped aircraft activities and utilization information within the 20,000 square miles R-2508 airspace Complex. In this paper we also provide detailed AURS reports and examples of military and civilian aircraft activities obtained with AURS.
    • An Analysis of Error Tolerance Property of Spread Spectrum Sequence

      Daming, Hu; Tingxian, Zhou (International Foundation for Telemetering, 1999-10)
      This paper proposes a problem that the error tolerance property of spread spectrum sequence influences the performance of spread spectrum system. Then the relation is analyzed between the error tolerance property and the correlation property of binary sequence when correlation detection is proceeded, and the theoretical limitation of error tolerance is given. Finally, we investigate the relationship between the determination of the output decision threshold of correlation, the probability of correlation peak detection and the error tolerance of the spread spectrum sequence.

      Haiou, Zheng; Naitong, Zhang; Harbin Institute of Technology (International Foundation for Telemetering, 1999-10)
      In this paper, a hybrid frequency division multiple access/code division multiple access (FDMA/CDMA) system in a Rician fading channel is described and analysis. The performance of the hybrid system is compared with a wideband CDMA system, which occupies the same total bandwidth. The results show that for DPSK modulation with a RIKE receiver, a hybrid system can have a greater capacity with a strong direct path component or a high signal to noise ratio (SNR). Otherwise, a wideband system remains optimal.

      Hui, Liu; Qishan, Zhang; Beijing University of Aeronautics and Astronautics (International Foundation for Telemetering, 1999-10)
      The coverage characteristics of the GLONASS constellation is analyzed. The almanac data of GLONASS navigation message are used in the computation according to the operation of the satellites. The ground traces of the GLONASS satellites are plotted. And the probability of visible satellite number is calculated under different latitude conditions. The results are analyzed to give descriptions of the GLONASS constellation. And they are compared with those of GPS's. The conclusion is verified that GLONASS constellation provides better coverage at high latitude.

      Hart, Alan D.; US ARMY YUMA PROVING GROUND (International Foundation for Telemetering, 1999-10)
      This paper briefly reports on concepts for hardening (physically toughening) crystal reference oscillators for the highly integrated program known as HSTSS. Within the HSTSS program is the L & S band transmitter development contract. The harshest requirements for this contract are surviving and functioning, to within 20 ppm of its center frequency, 30 ms after sustaining a shock pulse of 100,000 (g) for 0.5 ms on any axis. Additional requirements call for the transmitter to be no larger than 0.2 in3, and to operate within a 20 ppm frequency stability throughout the temperature range of -400 to +850 centigrade and during centrifugal spins of up to 300 Hz or 25,000 (g). Fundamentally the question is, is it feasible for any telemetry system to be capable of withstanding such harsh conditions and, to be practical on all DoD Test Ranges, still adhere to the stability tolerance guidelines set forth by the Range Commanders Council on Telemetry Standards - IRIG 106-96? Under "normal" conditions, stability requirements for "Range" transmitters are easily satisfied through the use of off-the-shelf crystal reference oscillators which provide the reference frequencies required within a transmitter’s phase lock loop circuitry. Unfortunately, the oscillator is also the most vulnerable part of a transmitter to the conditions listed and is the key to this problem. The oscillator’s weak points are in its resonator’s fragile quartz structure (the blank) and support mechanism. The challenge is to invent and adapt this area to these newer harsher conditions and to do it in the smallest space ever required.

      Rice, Michael; de Gaston, David; Davis, Adam; German, Gus; Bettwieser, Christian; Brigham Young University (International Foundation for Telemetering, 1999-10)
      Initial results of wideband channel sounding experiments sponsored by the Advanced Range Telemetry (ARTM) program are presented. Data collected at Edwards EAFB during the Winter 1998-1999, are analyzed in the frequency domain to estimate the number, strength, and delays of the significant multipath reflections observed during the experiments. We observe that the channel is adequately modeled using two or three multipath reflections. The multipath fade events are correlated with recorded bit error rates and transmitter location to provide a comprehensive overview of the channel characteristics. Summaries from two test flights are included where it is seen that the 2- and 3-ray channel models provide excellent models for the data. In general, the 3-ray model captures the essential features of the multipath interference. In this model the first multipath is a strong specular reflection with relative amplitude greater than 0.5 and relative delay in the 30 to 70 ns range. The second multipath is a much weaker reflection with relative amplitude less than 0.5 and relative delay in the 175 to 325 ns range.

      Youssef, Ahmed H.; TYBRIN Corporation; Edwards Air Force Base (International Foundation for Telemetering, 1999-10)
      This paper presents the future of optical networking via photonic switches as a potential replacement for the existing electronic cross-connects. Although optical amplifiers are now mainstream and wave division multiplexing (WDM) systems are a commercial reality, the industry’s long-term vision is one of the all-optical network. This will require optical switching equipment such as all-optical or “photonic” cross-connect switches that will provide packet switching at an optical layer. Currently, as voice calls or data traffic are routed throughout Range and commercial networks, the information can travel through many fiber-optic segments which are linked together using electronic cross-connects. However, this electronic portion of the network is the bottleneck that is preventing the ideal network from achieving optimal speeds. Information is converted from light into an electronic signal, routed to the next circuit pathway, then converted back into light as it travels to the next network destination. In an all-optical network, the electronics are removed from the equation, eliminating the need to convert the signals and thereby significantly improving network performance and throughput. Removing the electronics improves network reliability and restoration speeds in the event of an outage, provides greater flexibility in network provisioning, and provides a smooth transition when migrating to future optical transmission technologies. Despite the fact that photonic switching remains uncommercialized, it now seems apparent that the core switches in both the public networks and DoD Range networks of the early 21st century will probably carry ATM cells over a photonic switching fabric.

      Kaiser, Julius A.; Herold, Fredrick W.; Fredrick Herold and Associates, Inc. (International Foundation for Telemetering, 1999-10)
      Employment of the retro-directive technique described in Reference 1 describes a totally Autonomous Ground Station providing hemispheric coverage and continuous tracking. This System establishes communications between the satellite and ground station without human intervention or moving parts. When a satellite is in view, the ground station beacon antenna, using CDMA, enables the desired satellite transmitter and directs its beam to the ground station. The ground station, using the satellite’s transmitted signal, directs it’s receive and transmit arrays to point the ground station beams to the satellite, establishing two-way communications. The process is automatic and provides continuous horizon to horizon tracking.

      Anderson, Mike; Militch, Peter; Pickens, Hugh; AlliedSignal Technical Services (International Foundation for Telemetering, 1999-10)
      In 1998, AlliedSignal Technical Services (ATSC) installed three fully autonomous 13-meter satellite tracking systems for the Integrated Program Office of the National Oceanic and Atmospheric Administration (NOAA) at the Command and Data Acquisition Station near Fairbanks, Alaska. These systems track and command NOAA Polar Orbiting Weather Satellites and Defense Meteorological Satellites. Each tracking system operates for extended periods of time with little intervention other than periodic scheduling contacts. Schedule execution initiates equipment configuration, including establishing the RF communications link to the satellite. Station autonomy is achieved through use of a robust scheduler that permits remote users and the System Administrator to request pass activities for any of the supported missions. Spacecraft in the mission set are scheduled for normal operations according to the priority they have been assigned. Once the scheduler resolves conflicts, it builds a human-readable control script that executes all required support activities. Pass adds or deletes generate new schedule scripts and can be performed in seconds. The systems can be configured to support CCSDS and TDM telemetry processing, but the units installed at Fairbanks required only telemetry and command through-put capabilities. Received telemetry data is buffered on disk-storage for immediate, post-pass playback, and also on tape for long-term archiving purposes. The system can autonomously support up to 20 spacecraft with 5 different configuration setups each. L-Band, S-Band and X-Band frequencies are supported.

      Archibald, James K.; Kelsey, Jed M.; Brigham Young University (International Foundation for Telemetering, 1999-10)
      This paper describes the experiences and final design of one team in a senior design competition to build a soccer-playing robot. Each robot was required to operate autonomously under the remote control of a dedicated host computer via a wireless link. Each team designed and constructed a robot and wrote its control software. Certain components were made available to all teams. These components included wireless transmitters and receivers, microcontrollers, overhead cameras, image processing boards, and desktop computers. This paper describes the team’s hardware and software designs, problems they encountered, and lessons learned.
    • Bandwidth Efficient Signaling Using Multiscale Wavelet Functions and its Performance in a Rician Fast Fading Channel Employing Differential Detection

      Moon, Todd K.; Lo, Chet; Utah State University (International Foundation for Telemetering, 1999-10)
      In this paper, orthogonal wavelets are employed to produce multiscale signaling. It is shown that signaling using these functions is bandwidth efficient compared other signaling schemes, including SFSK and GMSK. For signaling in Rician fast fading channel, it is also shown that scaling functions is superior in term of achieving low level of probability of error. Even for multiscale signaling, the level probability of error achieved by using wavelet is lower than conventional flat-top signaling. The benefits are largest for channels with small B(D)T , in which the degradation due to fading is most severe.

      Tsai, Kuang; Lui, Gee L.; The Aerospace Corporation (International Foundation for Telemetering, 1999-10)
      Gaussian Minimum Shift Keying (GMSK) is a form of Continuous Phase Modulation (CPM) whose spectral occupancy can be easily tailored to the available channel bandwidth by a suitable choice of signal parameters. The constant envelope of the GMSK signal enables it to corporate with saturated power amplifier without the spectral re-growth problem. This paper provides a quantitative synopsis of binary GMSK signals in terms of their bandwidth occupancy and coherent demodulation performance. A detailed account of how to demodulate such signals using the Viterbi Algorithm (VA) is given, along with analytical power spectral density (PSD) and computer simulated bit-error-rate (BER) results for various signal BT products. The effect of adjacent channel interference (ACI) is also quantified. Ideal synchronization for both symbol time and carrier phase is assumed.

      Gao, Wei; Wang, Shih-Ho; Feher, Kamilo; University of California; Digcom, Inc. (International Foundation for Telemetering, 1999-10)
      Blind adaptive equalization with application for Non-Linearly Amplified (NLA) quadrature amplitude modulation (QAM) systems in multipath selective fading channels is presented. With an offset sampling strategy in the receiver, the proposed blind equalization using Constant Modulus Algorithm (CMA) exhibits a fast convergent speed for a family of quadrature modulated systems in NLA and multipath fading channels. Feher’s patented Quadrature Phase Shift Keying (FQPSK) and Feher’s Quadrature Amplitude Modulation (FQAM) which correspond respectively to 4-state and 16-state QAM are used due to their higher Radio Frequency (RF) power and spectral efficiency in NLA channel. It has been shown that blind adaptive equalization can significantly open the eye signals in multipath frequency selective fading channels.