Porter, Jim; Meyers, Tom; SEMCO (International Foundation for Telemetering, 1994-10)
      Embedded "Card-Based" receivers are one of the latest innovations in telemetry reception. These products provide substantial power and flexibility in a small form factor (one slot, PC or VME). In many applications they are a cost effective alternative to conventional telemetry receivers. This paper analyzes currently available products with regard to their features, capabilities, and performance, as well as highlighting typical applications.

      Hines, Dennis O.; Rhea, Donald C.; Williams, Guy W.; Edwards Air Force Base; SPARTA Inc. (International Foundation for Telemetering, 1994-10)
      The rapid technology growth in the aerospace industry continues to manifest itself in increasingly complex computer systems and weapons systems platforms. To meet the data processing challenges associated with these new weapons systems, the Air Force Flight Test Center (AFFTC) is developing the next generation of data acquisition and processing systems under the Advanced Data Acquisition and Processing Systems (ADAPS) Program. The ADAPS program has evolved into an approach that utilizes Commercial-Off-The-Shelf (COTS) components as the foundation for Air Force enhancements to meet specific customer requirements. The ADAPS program has transitioned from concept exploration to engineering and manufacturing development (EMD). This includes the completion of a detailed requirements analysis and a overall system design. This paper will discuss the current status of the ADAPS program including the requirements analysis process, details of the system design, and the result of current COTS acquisitions.

      Mitchell, B. J.; The Johns Hopkins University (International Foundation for Telemetering, 1994-10)
      Current theories concerning the surface of Titan postulate the existence of large, possibly oceanic, bodies of liquid ethane/ammonia plus various other chemicals. ESA's Huygens probe is designed to gather oceanographic data on Titan. If the postulated oceans or lakes do exist, follow up missions of an oceanographic nature will be planned. This paper provides a concept for a modified XBT (eXpendable Bathymetric Thermograph) probe design that will provide more data than just temperature as a function of depth. By judicious use of acoustic telemetering links, data on the sound speed profile and constituents of the ocean can be obtained. The exo-oceanographic data collected will have important ramifications for oceanographic studies on Earth.

      O'Brien, R. Michael; Loral Test & Information Systems (International Foundation for Telemetering, 1994-10)
      With today's telemetry systems, an hour-long analog test tape can be digitized in one hour or less. However, the digitized data produced by today's telemetry systems is usually not in a format that can be directly analyzed by the test engineer's analysis tools. The digitized data must be formatted before analysis can begin. The data formatting process can take from one to eight hours depending on the amount of data, the power of the system's host computer, and the complexity of the analysis software's data format. If more than one analysis package is used by the test engineer, the data has to be formatted separately for each package. Using today's high-speed RISC processors and large memory technology, a real-time Flexible Data Formatter can be added to the Telemetry Front End to perform this formatting function. The Flexible Data Formatter (FDF) allows the telemetry user to program the front-end hardware to output the telemetry test data in a format compatible with the user's analysis software. The FDF can also output multiple data files, each in a different format for supporting multiple analysis packages. This eliminates the file formatting step, thus reducing the time to process the data from each test by a factor of two to nine.

      Bougan, Timothy B.; Science Applications International Corporation (International Foundation for Telemetering, 1994-10)
      In order to meet the high-speed and high-density recording requirements for today's development and testing environments, we are seeking to merge the cutting edge technologies of tiny, high-performance disk drives and field programmable gate arrays (FPGAs) to build a high-speed compact disk recorder (CHSDR). Specifically, we designed, built, and tested a multi-drive controller that handles the interleaving of data to eight inexpensive IDE drives. These drives and controller comprise a "cell" capable of transferring data at 2.45 MB/sec (4 to 5 times the rate of a single drive). Furthermore, these "cells" can be run in parallel (with a single controller interleaving data between the cells). This "tree" effect multiplies the data rate by the number of cells employed. For example, 8 cells (of 8 drives each) can reach nearly 20 MB/second (sustained) and can be built for less than $30,000. The drives we used are the size of match boxes (the Hewlett Packard KittyHawk). These tiny drives hold 42 megabytes each and can withstand 150 Gs while operating. The cell controller is a Xilinx 4005 FPGA. Furthermore, we've designed a 120 MB/sec RAM FIFO to buffer data entering the system (to account for unavoidable drive seek latencies). In short, the compact high-speed disk array is a small, relatively low cost recording solution for anyone requiring high data speed but modest data volume. Missile shots, nuclear tests, and other short-term experiments are good examples of such requirements.
    • Distributed Interactive Simulation (DIS): An Overview Of The System And Its Potential Uses

      Boyd, Edward L.; Novits, Charles S.; Boisvert, Robert A.; Encore Computers (International Foundation for Telemetering, 1994-10)
      The Distributed Interactive Simulation (DIS) concept, since its inception, has been defined into three separate but distinct areas of service. • Viewing of data in the real-time environment. • Multiple range viewing and usage of"real-time data." • Problems with the sharing of information through DIS. This paper will discuss the DIS concept and some of the various methods available to display this data to users of the system.

      Gaskill, David M.; ASTRO-MED INC. (International Foundation for Telemetering, 1994-10)
      This paper will examine real-time ethernet capabilities in general and will describe in detail a practical implementation of an Ethernet interface that allows commands and data to be sent to a thermal array recorder using a standard TCP/IP, Novell, or similar interface. This interface allows two types of data transmission. First, real-time data may be sent at low rates for slow speed monitoring or, second, high speed packets may be sent for storage in local FIFO memory. A header containing sample rate information allows the recorder to reconstruct the data on paper smoothly so that it has the appearance of real-time recording but is slightly delayed. In addition, normal host control commands may be interleaved with data for a complete high speed digital data system.

      Cardinal, Robert; Loral Test & Information Systems (International Foundation for Telemetering, 1994-10)
      The success of the client/server paradigm for modern networked telemetry systems continues to stress the LAN that carries data generated from the acquisition front ends to the display workstations and the file servers on the LAN. As the number of LAN-attached devices such as Loral's System 500 Model 550 (Loral 550) telemetry front end, workstations, and file servers grows beyond two, the Ethernet LAN collision rates increase and the throughput slows down. At what point the network performance declines is a function of the specific application bandwidth demands required. This paper describes a new method for boosting LAN performance by providing Ethernet switching and protocol filtering. The performance of the LAN is critical to the performance of the complete telemetry enterprise architecture.
    • Use of a Commercial Visual Programming Language to Simulate, Decommutate, Test and Display a Telemetry Stream

      Wells, George; Baroth, Ed; California Institute of Technology (International Foundation for Telemetering, 1994-10)
      The advantages of using visual programming to create, modify, test and display a telemetry stream are presented. The failure to fully deploy the high-gain antenna of the Galileo spacecraft has resulted in a software redesign of the computer systems onboard the spacecraft to support the low-gain antenna mission. Visual programming software is being used to test new algorithms as part of the ground support for the spacecraft Test Bed. It is very important that any new software algorithms be thoroughly tested on the ground before any modifications are made to the spacecraft. The advantage of using a visual programming language (LabVIEW, National Instruments) is that it provides easy visibility into the decommutation process that is being modified by the Galileo programming support team. In addition, utilities were written using visual programming to allow real-time data display and error detection. A data acquisition board is used to clock in the actual synchronous telemetry signal from the Test Bed at rates below 10 kHz. The time to write and modify the code using visual programming is significantly less (by a factor of 4 to 10) than using text-based code. The gains in productivity are attributed to the communication among the customer, developer, and computer that are facilitated by the visual syntax of the language.

      Horan, Stephen; Minnix, Timothy; New Mexico State University (International Foundation for Telemetering, 1994-10)
      Small satellites have been perceived as having limited access to NASA's Space Network consisting of the TDR satellites and associated ground terminals. This paper presents the potential for access of the space network using basic small satellite design constraints and a simple helical antenna for the communications links. From the analysis derived through simulation of the orbit of both satellites, small satellites can be shown to have up to 30 minutes per orbit of single-TDRS access. Data rates on the order of 100 kbps are possible in this configuration with total daily data volumes in excess of 100 Mbits being achievable. Design parameters are given for a variety of orbital inclination angles and spacecraft transmission powers to illustrate the expected available contact time for such small satellites to the Space Network. This is compared with typical access time through a fixed ground station.
    • Portable Airborne Digital Data System Recorder

      Harris, Kevin E.; Veda Incorporated (International Foundation for Telemetering, 1994-10)
      Veda Incorporated has developed an airborne instrumentation recorder for a major commercial aircraft manufacturer. The recorder was developed for use in the aircraft company's Portable Airborne Digital Data System (PADDS), a small scale data acquisition and monitor system used for flight testing. The recorder is designed around an off-the-shelf 8mm tape drive, the Exabyte 8505. It records asynchronous, variable-rate data in a proprietary 24-bit recording format, and allows the data to be played back in real time. Its RS-422 control interface is designed to imitate the recorder used in the company's large scale data acquisition system, the Ampex DCRSi-II. Special provisions allow it to withstand the environment of an airplane's EE bay.
    • Planned Evolution of Range Telemetry and Communications into the Public Data Network

      Erdahl, Mike; Loral Test & Information Systems (International Foundation for Telemetering, 1994-10)
      The area of range telemetry and communications has been under budget constraints and interoperability enhancement requirements for some time. The near-term onslaught of multimedia communications offerings by telephony and communications companies is certain to cause range engineering personnel to conduct extensive research and possibly make numerous decisions on procurements and technologies before standards are finalized. This paper will address a low-risk migration path for range telemetry to the new multimedia communications for ranges based on current capabilities. This migration path has an end goal of positioning the ranges to take advantage of future multimedia communications as they become available, while leveraging off of current products and procurements, without a major investment.
    • Dual Function Transponder: A Data Link for the Next Generation

      DeViso, Hans; Troth, Bill (International Foundation for Telemetering, 1994-10)
      Future U.S. Navy at-sea and littoral battle group training range instrumentation requires a new, secure, high data rate link This link must be capable of providing the ranges with the capacity to increase the number of players, increase the amount of threat simulation, and allow an improved Global Positioning System (GPS) based position tracking system to be implemented This paper describes a Dual Function Transponder (DFT) capable of operating on any R-CUBED (Relay, Reporter, Responder) based range as well as any TACTS/ACMI range without modification of either range type. In addition, the DFT provides a new increased data rate capability for use by planned future ranges, enabling a dramatic increase in the number of participants as well as significantly increasing the quantity of data that can be communicated by each player. Miniaturization and programmability are the keys to this development and many of the methods used are described.
    • The Evolution of a Telemetry Groundstation Utilizing Today's Open Standards

      Friedman, Paul; Loral Test & Information Systems (International Foundation for Telemetering, 1994-10)
      Computer industry and government standards have had a profound effect on modern telemetry ground stations. Installations are no longer one-of-a-kind inflexible systems built to the specifications of a single user - meeting their needs without regard to the rest of the community. This paper will examine the effect that the evolution of significant graphics, network, operating system, and architecture standards has had on commercial telemetry ground station system products. It will also explore the issue of "open" versus proprietary architectures. The paper closes with a description of a system designed from its very inception to meet and grow with standards.
    • Binary PCM/FM Tradeoffs Between Spectral Occupancy and Bit Error Probability

      Law, Eugene L.; NAWCWPNS (International Foundation for Telemetering, 1994-10)
      The bit rates of telemetry systems are increasing rapidly. Higher bit rates occupy more spectra and result in decreased link margin. The major signal parameters that affect the spectral occupancy and bit error probability (BEP) of binary pulse code modulation (PCM)/frequency modulation (FM) signals are the bit rate, code, premodulation filter, and peak deviation. The measured spectral occupancy is also affected by the spectrum analyzer (or other measurement equipment) settings. Additional parameters that affect the BEP include the receiver intermediate frequency (IF) filter, the FM demodulator, and the bit detector. This paper will present the effects of these parameters on the measured 99% and -60 dBc bandwidths and the BEP of binary PCM/FM telemetry signals. Normalized BEP and bandwidth curves will be presented.
    • Design Equations for a Specified Bit Error Rate for PCM/FM+FM/FM and Optimum Bandwidths

      Carden, Frank F.; New Mexico State University (International Foundation for Telemetering, 1994-10)
      A PCM/FM+FM/FM system combines the bit sequence with the modulated subcarriers at baseband and the resultant modulates the carrier. This paper concerns the design of this composite system. Such a system combines the spectral efficiency of the analog system with the accuracy of a PCM system when needed for specific sensors and allows the direct transmission of binary computer words if necessary. The impact of the subcarriers on the bit error rate of the bit sequence is determined. Equations are given which allow the degradation of the FM/FM channels by the bit sequence to be determined. Further, it is shown in this work that as the IF bandwidth is increased above twice the bit rate, the peak deviation of the carrier by the bit sequence is no longer .35 times the bit rate. An optimum value for IF bandwidths is determined. The developed design equations allow the design of the composite system with a specified bit error rate and a specified signal to noise ratio in the subcarrier channels.

      Turner, W. C.; Potter, R. A.; Electro-Magnetic Processes, Inc. (International Foundation for Telemetering, 1994-10)
      A remotely-operated ground telemetry tracking and receiving station is described. The station, operating in a space-diversity mode, is capable of reception and tracking both at VHF and at UHF. The station can be configured and operated from a distance of 240 km using a wide-band land data link. Uplink command at VHF is included as part of the station.

      Richard, Gaetan C.; Gonzalez, Daniel G.; DECS, Inc; Malibu Research, Inc (International Foundation for Telemetering, 1994-10)
      The design of a telemetry tracking system is generally centered around its desired RF performance which is typically specified in terms of beamwidth, gain and/or G/T. These parameters determine the size of the reflector used in a given application and consequently dictate the required size and performance of the associated pedestal. Any subsequent improvement in the RF performance of such a system is primarily achieved by increasing the size of its reflector. The magnitude of the improvement realized is therefore limited by the load handling capability of the pedestal. In most instances, the substitution of a larger reflector with its increased inertia and wind loading causes a significant degradation in the dynamic performance of the tracking system. This paper describes how the figure of merit (G/T) of a specific dual axis telemetry tracking system can be improved by a minimum of 7.3 dB/K° without impacting its dynamic performance or increasing its weight. These impressive results are made feasible by the innovative pairing of a unique design planar reflector with a novel implementation of the conical scanner technology. The FLAPS™ reflector incorporates a newly developed concept which features lightweight construction and very low wind load coefficients [1, 2]. The conical scanner is a lightweight version of the DECS tracking feed system described in the referenced technical paper [3].
    • GPS as a Telemetry Sensor

      Qishan, Zhang; Xianliang, Li; Beijing University of Aeronautics and Astronautics (International Foundation for Telemetering, 1994-10)
      GPS is required in today's vehicle tracking and navigation applications. The Navigation Satellite Timing and Ranging (NAVSTAR GPS) is an all-weather. Radio based, satellite navigation system that enables users to accurately determine 3-dimensional position, velocity and time. So it is an intelligent sensor intended to be used as a component in a system for public service.
    • The Development of Application Software for Telemetry Groundstation Remote Control and Analysis

      Peterson, Dwight M.; Naval Warfare Assessment Division (International Foundation for Telemetering, 1994-10)
      Fleet telemetry stations were established in the 1965-1972 time frame to satisfy U.S. Navy requirements for weapons system training support. These stations are currently located at the Atlantic Fleet Weapons Training Facility (AFWTF), Puerto Rico; Naval Air Station (NAS) Oceana, Virginia; the NATO Allied Missile Firing Installation (NAMFI), Crete, Greece; and White Beach, Okinawa, Japan. The mission of these telemetry stations is to collect, record, and process telemetered missile data during exercises involving ships and aircraft. The Naval Warfare Assessment Division uses the data to analyze weapons system performance during missile firing exercises conducted on fleet training ranges associated with these telemetry stations. Since these stations were originally installed, missile weaponry has advanced in sophistication, complexity, and usage. New weapons and tactics have been developed and introduced into the fleet which have not been matched by corresponding technology enhancements in the existing fleet telemetry stations. As a result, the Program Manager for Tactical Training Ranges (PMA-248) tasked the Naval Warfare Assessment Division to develop a computer-controlled telemetry ground station design capable of meeting current and future fleet training range requirements. This program involved the design, procurement, integration, and testing of telemetry ground station hardware and software required to meet fleet telemetry data collection requirements. Full Operational Capability of the first system, which was installed at AFWTF in Puerto Rico, was achieved in March of 1994. To date, the new telemetry ground station hardware and software has been used to support complex fleet training exercises, Combat System Ship Qualification Trials, Development Tests, and Operational Tests of U.S. and foreign navies. This paper will present the hardware and software design principles used to develop a computer-controlled telemetry ground station and the demonstrated performance benefits which have been realized.