Search

This report has been prepared to summarize a test validation effort for an accelerated life testing model which uses a wide parametric Bayesian Analysis Methodology. Step stress testing was performed on seven (7) Joint Tactical Information Distribution System (JTIDS) Class 1 synthesizer detector, radio frequency assemblies. Failure data and analyses are provided. The report addresses issues concerning how to demonstrate high reliability (Mean-Time- Between-Failure values of 10,000 hours or more) on procured Air Force systems without incurring excessive testing costs., See also Part 1, ADA260182.

This report has been prepared to summarize a test validation effort for an accelerated life testing model which uses a wide parametric Bayesian Analysis Methodology. Step stress testing was performed on seven (7) Joint Tactical Information Distribution System (JTIDS) Class 1 synthesizer detector, radio frequency assemblies. Failure-data and analyses are provided. The report addresses issues concerning how to demonstrate high reliability (Mean-Time- Between-Failure values of 10,000 hours or more) on procured Air Force systems without incurring excessive testing costs.

This report documents the results of the concept definition phase for a high capacity wideband general purpose data/communications bussing system. A 'Flexible Intraconnect' bus concept is described in terms of its use to achieve physical and functional modularity in the design, implementation and operational deployment of command and control (C2) centers of the Tactical Air Force (TAF). Flexible Intraconnect (FI) design parameters are established in terms of traffic loading estimates and requirements of evolving configurations of C2 centers of the TAF. Surveys of data distribution system architectures, current and developing technologies and C2 device interfaces are provided. A design of a Flexible Intraconnect having high data rate and capacity, positive flow control and configuration flexibility is documented. A standardized interface for physical and functional device to bus access is described. Descriptions of the major functional elements of the FI are provided along with top level block diagrams. The design was analyzed and preliminary estimates of error performance, reliability, capacity and response times were derived. Results obtained from this phase will be used in specifications for the subsequent development phase of the FI program., See also Volume 2, ADB046391

A practical FI design concept which meets Tactical Air Force Modular C3 goals has been developed. It is recommended that the preliminary FI design be demonstrated and evaluated in a development program which connects typical C3 devices into an operational configuration. Conclusions: The developed FI concept meets TAF MOD C3 goals, A MOD C3 Standard Interface is defined which promotes C3 interoperability; and The preliminary design exploits advanced technology and is ready to be implemented. Recommendation: Develop the Flexible Intraconnect hardware and software to provide a vehicle for demonstrating and evaluating the concept in a realistic TAF C3 environment., See also Volume 1, ADB046390.

Existing maintainability prediction techniques are not accurate estimators of current electronic equipment/system characteristics. A new time synthesis prediction technique is developed which directly relates diagnostic/ isolation/test subsystem characteristics and other design characteristics to equipment/system maintainability parameters. The developed methodology includes a detailed prediction procedure for use when final design data is available, and an early prediction procedure for use when preliminary design data is available. Predicted parameters include mean time to repair, maximum (percentile) time to repair, maintenance man-hours per repair, and fault isolation resolution. Also included is a comprehensive set of time standards applicable to physical maintenance actions associated with current construction and packaging techniques.

Environmental Stress Screening is now being employed throughout the defense industry as a means of precipitating latent part and workmanship defects prior to fielding, with the expectation that improved field reliability and reduced support costs will result. The objective of this study was to develop a quantitative technique for planning, monitoring and controlling the cost effectiveness of stress screening programs for electronic equipment and to prepare a draft military standard based on the developed technique. Latent defects are introduced in equipment through defective parts and deficiencies in the manufacturing assembly process. Design related defects, though not insignificant, are not considered in the techniques developed. Stress screens act on part and workmanship defects with resulting fallout, but since screens are less than 100% effective, some defects escape in fielded equipment. A method for estimating the number of defects initially present was developed and is described later. The effectiveness of stress screens is measured by test strength determined from screening strength equations developed in a previous study and updated in this study based on acutal screening results and test detection efficiency. The question of what is a reasonable number of defects to escape is addressed based on equipment complexity and a tradeoff of stress screening cost and resulting field reliability.

Although RADC's interest in nonelectronic/mechanical components is limited to those used in electronic systems, this revised note book contains failure data and reliability methods pertaining to a variety of applications. Its objective was the collection, analysis, and presentation of nonelectronic component failure data and the presentation of analytical methods that form the state-of-the-art in nonelectronic reliability analysis. Topics include: Applicable statistical methods for nonelectronic reliability; Reliability specifications; Special application methods for Reliability Prediction; Part failure characteristics; and Reliability demonstration tests. Keywords: Mean time between failures; Mechanical reliability; Statistical methods; Failure rate., Supersedes Rept. no. RADC-TR-75-22, AD-A005 657.

This report presents the results of a study to develop quantitative and qualitative techniques for planning, monitoring and evaluating stress screening programs during electronic equipment development and production. A screening and debugging optimization (SDO) model developed on a prior study, RADC-TR-78-55, was revised to include current thermal cycling and vibration screening experience and an adaptive feature was added to allow stress screening program changes based on screening results.

This report presents the results of a quantitative investigation into the optimum selection of screening and debugging methods for the purpose of removing defects, and hence improving reliability, throughout the development process. A computerized optimization model has been developed which can be used to address three problem areas; (1) Select an optimum sequence of screens for a fixed dollar expenditure, (2) Select a sequence of screens which minimizes costs in the face of a fixed desired reliability improvement, and (3) Provide quantitative for performing screening/debugging tradeoffs. In order to implement the model it was necessary to obtain data to compute test strengths and test costs. The model includes four assembly levels, five types of screens (temperature cycling constant temperature, vibration constant power and power cycling), provides for introduction of defects at each assembly level and includes the rework cycle.

The object of the program is the establishment of a production capability for surface acoustic wave devices of varied design and material for the purpose of meeting estimated military needs for a period of two years after the completion of the contract and to establish a base and plans which may be used to meet expanded requirements. The primary requirement is the pilot line production of devices that are reliable, reproducible, and low cost. Fabrication for the 3rd, Confirmatory Phase of the program has been accomplished and environmental testing is nearing completion.

Testability represents the inherent susceptibility of electronics systems to undergo valid functional performance testing, fault detection and fault isolation, together with the characteristics of the test system mix of Built-in-Test and external test equipments. A high degree of testability is necessary to achieve the highest levels of system performance and availability at least costs of system development and operation since good testability allows for discovery and correction of faulty system operation with the least expenditure of program resources and within acceptable limits of elapsed time. The inherent testability needs to be systematically developed and integrated with the design of the system and the requirements for testability must be accorded the same level of recognition as performance, reliability, maintainability, availability, supportability, and safety. The Testability Notebook provides fundamental guidance for systematic establishment throughout the development cycle of the requisite inherent testability and comprehensive testability of the test resource mix in combination with the prime system design.

This report describes the manufacturing technology and test system that will enable detection, identification, and location of digital faults in the advanced missile electronic system that will be used in the 1980's. Emphasis is placed on the fault diagnosis of large printed circuit boards containing complex hybrid digital microelectronic circuits. The Hughes-enhanced, state-of-the-art, DTS-70 automatic test system installed at Redstone Arsenal as a result of this contract provides the capability to isolate digital faults in such circuit boards to the component level with a test comprehensiveness of 90% or better., Appendix to ADA093797.

During the reporting period (FY 1977), a High Speed Towed Array System (HSTAS) was conceived, designed, and fabricated. The system was successfully sea tested in July of 1977 in Exuma Sound in the Bahamas aboard the R/V Harris. In addition to the test being successful from the point of view of equipment operability at sea, the following program goals were achieved: a) The self noise results revealed that the 6 inch diameter module (FAM) was always quieter than the 3 inch modules, reaching a peak differential of approximately 15 dB in the frequency range between 80 Hz and 250 Hz at 18 knots towspeed. b) The demonstration (at sea) of the ability to eliminate ownship radiated noise interference from beam outputs by means of an adaptive filter employed as a noise canceller. Specifically, in the case of a broadband interfering signal, a maximum cancellation of 15 dB was achieved, while for the narrowband case the cancellation was 18 dB. For this latter effort, the R/V Harris was augmented acoustically by towing the HX-90 noise source.

The Automated Interactive Simulation Modeling System (AISIM) provides the user with the ability to do high level simulation of complex operational and distributed data processing systems. The purpose of this manual is to provide the AISIM user with a comprehensive guide for the use of the AISIM system on a VAX 11/780 computer. This manual is a straightforward reference document for the AISIM user. Chap 1 introduces this document, detailing the organization of this document, the document conventions and applicable documents. Chap 2 is an overview of the concepts used in modeling and simulation of systems using AISIM. Chap 3 contains a detailed description of the AISIM modeling constructs. Chap 4 describes the interface between the AISIM software and the host computer's time sharing system. Chap 5 through 10 present information of the various system user interface levels, including detailed descriptions of prompts and commands. Chap 11 discusses AISIM simulation results and how to interpret them. Appendix A presents operational procedures and other information which is useful for the user to know but not mandatory for using the system. Appendix B lists simulation error messages with a description of their meaning. Appendix C is a glossary of AISIM terms. Appendix D contains a detailed description of the message routing submodel. The tool is designed for the operations analyst or engineer as a workbench for investigating the impact of system alternatives., See also AD-A161 436.

This document describes the procedures for installing the automated interactive simulation modeling system (AISIM) on a Vax 11/780 computer and for conducting acceptance testing of the system. This document also contains a description of the contents of the AISIM delivery tapes and the tapes and the steps for building the AISIM system. The description of the AISIM delivery tapes includes a list of all of the files on the tapes and a brief description of each file. The instructions for building AISIM include steps on dumping the tape files to disk and changing all necessary execution command files so that AISIM will execute on a new host.

The HFI program objective was to establish the test and fault isolation requirements for complex digital, hybrid microelectronic assemblies (D/HMAs) of present, and future, production missile electronics. High production rate test and fault isolation of D/HMAs, would use a single probe (Autoprobe or AP) automated for X, Y, Z position, and operating under bus control of an external host computer of ATE system. Project R1023 hardware (HW) and software (SW) were also to be compatible with the ATE system HW and SW previously delivered to MICOM under project R783242. Work Accomplished: Digital Hybrid Microelectronic Assembly (D/HMA) Survey; Autoprobe Positioner Survey; Positioner AP Adaptation; HFI Autoprobe System Overview; Autoprobe Interface Software Elements; Test Candidate Hardware; Test Software; HFI Autoprobe System Data and Performance., See also Attachment 1, AD-A152 687.

This training manual presupposes virtually no programming experience and is intended to provide step by step information necessary to begin using AISIM as hosted on a VAX 11/780. It is not intended as a complete account of the system, and many topics covered in the companion AISIM User's Manual are covered here in less detail, or not at all. For further details on the operation of AISIM or on the kind of simulation AISIM is adapted to, the reader is referred to the more detailed AISIM User's Manual. This manual consists of seven sections. This first section provides a brief overview of AISIM and its main concepts. Sections 2, 3, and 4 concern the Design User Interface (DUI), i.e., that part of AISIM in which models are created. Section 5 describes the complete construction of a simple model. Section 6 turns to the use of the Analysis User Interface--the part of AISIM where simulation and analysis occur--using the model developed in Section 5 as an example. Finally, Chapter 7 will document the creation, simulation and analysis of a more complex system.

This report describes the investigations and analyses performed in connection with revising and updating the Nonelectronic Reliability Notebook (Formerly RADC-TR-75-22). It includes detailed descriptions of the statistical analyses performed, the data base on which the Nonelectronic Reliability Notebook is based, new part classification outlines, and a section on advanced statistical techniques for analyzing life data. Keywords include: Mechanical Reliability, Weibull Distribution, Exponential Distribution, Nonelectronic Part Failure Data, and Statistical Analysis., Revision A to report dated Jan 75, AD-A005 657.

This final report presents the results, supporting data, and recommendations relating to an automatic test probe system (Autoprobe or AP). The manufacturing technology effort described by this report covers automatic test and fault isolation of digital hybrid microelectronic devices (D/HMAs) used in current and future production missile systems. A need for the single automatic probe, or Autoprobe, system was established by high production rate test and fault isolation of D/HMAs having complex LSI, microprocessor devices, and large number of I/O interconnections. An overview and objectives of project 1023 (or HFI Program) are presented in Section 1 of this report. Section 2 describes the work accomplished and includes the successful results of the Industry Demonstration for test and fault isolation of a D/HAM. Section 3 contains recommendations to achieve a full production type Autoprobe system and suggested future effort or study towards necessary AP improvements. This document only provides two Fortran language programs and two machine language programs that were compiled.

This report documents the engineering effort applied during this Manufacturing Methods and Technology (MM/T) contract on two distinct SAW devices using grooved reflective arrays on two different piezoelectric substrate materials. One device is 60 MHz by 60 microsecond down chirp linearly-dispersive filter operating at 200 MHz using lithium niobate and the second device is a two-part, 100 KHz bandwidth resonator operating at 400 MHz using quartz. The reflective is formed by an ion beam etch process. The degree of time-linearity on the RAC filter was achieved by use of metallic phase correction patterns. With a common pattern, wth phase error was reduced to about 18 degrees (RMS); with a second correction pattern designed for each individual RAC, the phase error was further reduced to about 7 degrees (RMS). The corresponding sidelobe levels in the time-domain pulse compression loop using an ideal matched filter were 25 and 32 dB, respectively. (Author)

This report documents the development, evaluation, and design of mainbeam anti-jam techniques for successful operation of a C-band tracking radar in advanced ECM environments. The techniques addressed in this study employ an antenna array consisting of omnidirectional or high-gain subarray elements followed by a signal processor to remove mainbeam jamming and provide target detection and tracking. The signal processing techniques that were considered are similar well-known techniques used in the areas of adaptive array processing and high resolution spectrum estimation. Two procedures were developed and were shown to provide target detection in the presence of a high intensity mainbeam jammer. The extrapolation procedure employed extrapolation techniques to extend the apparent aperture of the antenna array and thereby achieve a narrow notch on the jammer while providing gain in the book direction of a nearby target. The maximum likelihood (ML) procedure provided both target detection and an estimate of its angle of arrival. The angle estimation feature offers a potential solution to the target tracking problem under mainbeam jamming conditions.

Application of heat pipe technology to cooling problems is an efficient means to reduce hot spot temperatures; overall thermal conductance is significantly improved as compared to conduction through a solid. This effort was focussed on the design and development of a heat pipe module which could be used to retrofit an efficient cooling system to an existing Integrated Power Switch (IPS) module. The design selected maximized the thermal performance of the heat exchange system by eliminating a dielectric barrier between the IPS power strip and the heat sink. This necessitated the use of isolation between the two power strips of the IPS to maintain normal circuit insertion capability; the overall package was also electrically insulated. At constant air flow pressure drop (different flow rates) the heat pipe module provided a reduction in component temperature rise by about a factor of three (3) at equal input power, or could handle approximately three (3) times the power of the conventional IPS thermal system for equivalent temperature rise. Measured thermal resistances of .17 and .51 C/watt were obtained for the heat pipe heat exchange system and the original IPS conduction heat sink, respectively, at a pressure drop of 0.60 inches of water. (Author)

Eight Navy technicians participated in an evaluation of the effectiveness of state tables in troubleshooting the Missile Control Unit (MCU) of the NATO Seasparrow Surface Missile System. In a repeated-measures design, the technicians used either state tables or ordnance publications (OPs) to troubleshoot 96 problems in the MCU. With state tables, 31 of 48 problems were solved in 1499 minutes. With OPs, nine of 48 problems were solved in 2027 minutes. Twice as many checks were made with OPs as were made with state tables. Seven of the eight subjects rated state tables as excellent or good. With OPs, the ratings were lower and less consistent, ranging from poor to good. In general, state tables were preferred over OPs. Results are discussed in terms of state table implementation in the fleet. (Author)

With the advent of microprocessors, considerable design activity has occurred in the development of semiconductor memories as an integral part of the family with the microprocessors. These memories tend to be organized in byte fashion or some submultiple or multiple of the 8 bits. Selected memories of this type have been evaluated and MIL-M-38510 detail specifications written for those devices deemed appropriate. Evaluation consisted of normal DC and AC parameter limit testing, functional tests and electrical characterization studies. The characterization studies included Schmoo plots of selected parameters that were considered critical, including AC timing requirements. The following types of memories were evaluated: Static RAMS, ROM, Fused PROM, Programmable Array Logic, Field Programmable Logic Arrays, Ultraviolet Erasable PROMS, and Electrically Erasable ROMS. Ten detail specifications were written for the foregoing types of parts as follows: Static RAMS - 1) 2147, 2147H, 2114, 2148; 2)6810; 3) 27S07A, 27S03A; 4) ROM - S6831B; 5) PAL - 10H8, 12H6, 14H4, 16H2; 6) FPLA - 82S100, 93458; 7) UV/EPROM-2716; 8) TMS 2532; 9) 6654; 10) EAROM-2810, 7810. (Author)

This is the Final report on phase three of the Adaptive Tracking System Study, which considers the application of adaptive filtering to passive sonar bearing estimation. The study was initiated because the adaptive filter structure seemed well suited to bearing estimation problems involving unknown input statistics and dynamic targets. In particular, (a) an adaptive filter does not require a priori power spectral information on signal and noise fields, (b) because it is iterative, it can track non-stationary inputs while preserving its underlying minimum mean square optimality criterion, and (c) since all the correlation information between adaptive filter inputs is contained in the filter weights, the potential exists to perform both broadband and narrowband tracking simultaneously. In summary, there are some genuine advantages in performance and perhaps even in implementation offered by the adaptive filter tracker over conventional trackers. The performance benefits come when signal or noise statistics are not known to the designer of the front-end filters on a conventional system. Implementation benefits can occur when sampling rates at the beamformer outputs are much slower than the time resolution required to achieve a specified angular estimation accuracy. The adaptive tracker interpolates between tap values rather than having to sample at a higher rate.

This report presents the final recommendations and conclusions, with supporting data, resulting from the contract option phase of contract DAAK40-78-C-0290. It describes the manufacturing technology and test system that will enable detection, identification, and location of digital faults in the advanced missile electronic systems that will be used in the 1980's. Emphasis is placed on the fault diagnosis of large printed circuit boards containing complex hybrid digital microelectronic circuits. The Basic Effort included an industry survey for digital printed circuit board test requirements and available test system capabilities, the D/PCB testability investigation and resulting design guide, the development of digital fault isolation methodology and the comprehensive selection of the optimum ATE that recommended the DTS-70 system. The contract option phase of this project involved the purchase and installation of the DTS-70 system, the selection of the PN-1635972 and the PN-1646178 D/PCBs for testing, the development of generalized test software and the development of the specific hardware and software needed to test these worst-case boards. (Author)

This report describes the manufacturing technology that will enable detection, identification, and location of digital faults in advanced digital missile electronic systems. Emphasis is placed on the fault diagnosis of large printed circuit boards containing complex digital hybrid microelectronic circuits to be used in the 1980's. The identified technology provides the capability to isolate digital faults to the minimum size component level, using state-of-the-art automatic test equipment. The effort included an industry survey for digital printed circuit board test requirements and available test system capabilities, the development of digital fault isolation methodology, and the identification of the corresponding optimum available automatic test hardware. The subsequent contract option phase of this project involves the purchase, setup, and demonstration of the selected fault isolation hardware/software system, using the developed techniques., Includes attachments of computer printouts.

The object of the program was the establishment of a production capability for surface acoustic wave devices of varied design and material for the purpose of meeting estimated military needs and to establish a base and plans which may be used to meet expanded requirements. The primary requirement was the pilot line production of devices that are reliable, reproducible, and low cost. Phase III involved fabrication of a large quantity of confirmatory devices which were sampled at a high rate and subjected to rigorous life and environmental testing. Phase III was successfully completed with delivery and acceptance of the confirmatory samples. The device configuration is detailed as it existed for Phase III along with assembly details, results and conclusions from the Confirmatory Sample production run. The Fourth Engineering Phase (Phase IV) of the program was pilot line production effort of 150 each of the devices scheduled to be delivered. Solder sealing was identified as a problem area during Phase IV for SAW devices in semiconductor pin packages. New solder seal screening and processing procedures were investigated. In addition, alternative sealing approaches were evaluated. These procedures, Tungsten Inert Gas (TIG) and projection and seam welding were demonstrated to be more compatible with SAW processing. They are especially suitable for high volume production., See also Volume 5, AD-A069 684.

A pulser with turn on-turn off switching capability in the nanosecond region has been fabricated and is presently in the preliminary stage of evaluation. The unit is designed to deliver a 1000 V pulse into a 50 ohm resistive load. (Author)

The AN/TPQ-37 Transmitter Test Bed will provide a vehicle for evaluating techniques for improving the reliability and maintainability of the AN/TPQ-37 Transmitter. Work includes design and fabrication of a major portion of the microprocessor based fault isolation subsystem. Support has been provided to ERADCOM in monitoring procurement of Advanced Design Traveling Wave Tubes. During a later phase of the program these TWT's will be evaluated in the AN/TPQ-37 transmitter. (Author)

This is the final report on phase 2 of a study contract to determine the usefulness of the LMS adaptive filter in a bearing tracker structure for passive sonar. Three potential advantages of such a structure over conventional trackers motivated the study, as follows (a) While conventional trackers require a priori knowledge of the input power spectra to optimize performance, the adaptive tracker is estimating the input spectra. This suggests that the adaptive tracker may be insensitive to incorrect a priori assumptions and variations of the input spectra, (b) Since all the correlation information between the split array outputs is contained in the adaptive filter weights, the potential exists to perform broadband and narrowband tracking simultaneously, and (c) Conventional trackers are essentially designed for stationary targets, modified for use with dynamic targets with the addition of a tracking loop. However, the adaptive filter weights are adjusted iteratively (dynamically) to satisfy a minimum mean square error criteria, which may provide advantages against moving targets., See also Phase 1, AD-A063 392.

Manufacturing processes to fabricate heat pipes for circuit cards were evaluated. These included shell and wick fabrication, shell and wick joining, and vacuum/fill and testing. Cost effective processes were selected to meet production requirements. A production facility was designed based on cost trade-offs. The results of the evaluation, selection of recommended manufacturing methods and the design of the production facility are presented. (Author)

No decision has been reached as to the semiconductor device that will be used as the switching element for the nanosecond pulsers. The evaluation of avalanche transistors, VMOS FET, and LASS devices is continuing. A contributing factor to the lack of progress during the early months of the contract was program staffing problems and late arrival of critical test equipment. (Author)

This report presents the results of a study and investigation of software reliability models. In particular, the purpose was to investigate the statistical properties of selected software reliability models, including the statistical properties of the parameter estimates, and to investigate the goodness of fit of the models to actual software error data. The results indicate that the models fit poorly, generally due to in most part the vagaries of the data rather than shortcomings of the models.

This report presents the results of a quantitative investigation into the relationship between reliability expenditures (costs) and reliability in the development phase for ground systems. The reliability program was divided into three phases: design, parts, and evaluation. In particular, three areas were addressed. First, quantitative relationships were developed for predicting reliability costs, by phase, of the reliability program and total cost, based on commonly available independent variables. Second, prediction models were developed for achieved reliability. Next, reliability gain (due to expenditures in each phase) was studied and models were developed for estimating reliability gain: total and by phase. Finally, optimal allocation of reliability resources was investigated. Models were developed and a solution found. The data base consisted of ten systems of relatively recent vintage. The data were subjected to an evaluation for validity and factors affecting reliability and reliability expenditures which could only confuse the results were normalized out of the data., Also available as GIDEP-347.40.00.00-F9-06.

The techniques traditionally in use for Failure Modes and Effects Analysis (FMEA) have been fragmented in approach and not fully automated. These limitations can result in FMEA's being performed which are inconsistent in quality and approach. The Advanced Matrix FMEA Technique is presented as a standardized FMEA technique, and the automation of this technique is discussed. Additionally, the results of research into component failure modes to support FMEA are presented. The Purpose of the study was to determine the feasibility of standardizing and automating FMEA techniques for electronics and to develop such techniques. FMEA is a bottom-up, inductive, failure analysis technique. This analysis, which is normally performed by reliability engineers, is used to support multiple disciplines. The analysis output supports reliability, maintainability, testability, logistics, and safety activities. The analysis starts with a single point, low-level failure and proceeds upward through the hardware under analysis to define the failure effect at each level.

The Display/Control Subsystem elements provide a flexible modular approach that is suited to the DCDRS system and mission configuration. The approach is modular in that the Enroute Console, Strike Console, and graphic Display Terminal all employ the same display-circuit modules, and the Enroute and Strike Consoles employ a common console structure., See also Volume 2, Part 3, AD-919 794L.

The unique operational and performance requirements of the Communication System for modern tactical Army helicopters are described. An integrated system architecture is described which satisfies these requirements and incorporates very high levels of automation thereby reducing pilot workload. The automation concepts include the use of a preloaded communication data base and a centralized communication processor containing advanced control, reconfiguration and message formatting software. Link analysis and simulation results are presented which show the performance capabilities of the system with respect to the projected mission requirements. NATO Furnished. (RH), This article is from 'The Design, Development and Testing of Complex Avionics Systems: Conference Proceedings Held at the Avionics Panel Symposium in Las Vegas, Nevada on 27 April-1 May 1987', AD-A198 666, p21-1 thru 21-8.

This paper reports on a prototype real-time distributed computer system which will be implemented in Ada. The goals of the Ada network are to support transparent distribution of application software and incremental growth, and to provide fault tolerant capabilities. Some of the motivations and methods for distributing software in a local network of communicating processors are discussed, in addition to the hardware configuration and software development facilities. The model of distributed Ada programs is then described. After the prototype software is implemented, the project will focus on assessing the performance characteristics of the network: specifically, on distribution, executive software, and Ada language overheads. (Author), This article is from 'Proceedings of the Annual Conference on Ada (Trademark) Technology (2nd) Held at Hampton, Virginia on March 27, 28, 1984', AD-A142 403, p55-61.

This report presents the results of a 12 month study program designed to obtain data on millimeter wave system electromagnetic compatibility characteristics. The period covered is from 6 Feb 1974 to 6 Feb 1975. Results described in the first three quarterly progress reports (references 1, 2 and 3) are summarized. Activities of the fourth quarter are described and recommendations for requirements of the millimeter wave electromagnetic compatibility specifications are included. The millimeter wave electromagnetic compatibility study was performed with the objective of obtaining data which can be applied in establishing an electromagnetic compatibility specification for millimeter wave systems operating in the frequency range of 10 to 100 GHz. The effort was designed to investigate millimeter wave EMC problems, to recommend electromagnetic interference reduction techniques and to up date present military EMC specifications and standards to include millimeter wave systems.

In order to integrate multiple sensor data into a single air picture, the individual sensor data must be expressed in a common coordinate system, free from errors due to site uncertainties, antenna orientation, and improper calibration of range and time. The process of ensuring the requisite error free coordinate conversion of sensor data is called registration. This paper develops a Generalized Least-Squares Estimation technique for sensor registration and compares quantitatively this technique with of some the standard methods in use today. (AN)

This study has resulted in the development of a comprehensive airborne radar simulation program that emulates the performance of modern Doppler filtering/CFAR techniques operating in a simulated nonstationary airborne clutter environment. Conventional and advanced adaptive Doppler filtering/CFAR techniques are implemented in the software which is created for the VAX 11/780 computer. The adaptive Doppler filtering techniques are based on modern spectral estimation methods: the autocorrelation lags estimate method (ALE); the forward-backward sample matrix inversion method (FBSMI); the maximum entropy method (MEM); the maximum likelihood/maximum entropy method (MLM/MEM); the modified least-squares autoregressive method (MLSA); and the principal eigenvector subspace method (PESM). Doppler filtering; CFAR processing; Pulse doppler radar; Maximum entropy method; Recorded clutter data; Airborne simulation.(jes)

The Automated Interactive Simulation Modeling System (AISIM) provides the user with the ability to do high level simulation of complex operational and distributed data processing systems. The purpose of this manual is to provide the AISIM user with a comprehensive guide for the use of AISIM version 5.0 on a VAX 11/780 computer.

This document is the Training Manual for the Hughes developed Automated Interactive Simulation Model (AISIM). This manual provides step-by-step information necessary to begin using AISIM on a VAX 11/780 computer. Keywords: Training, Simulation, Models, Subroutines, File management.

This document contains instructions for installing version 5.0 of the Automated Interactive Simulation Model (AISIM) onto a VAX 11/780 computer and a list of changes included in this version.

This acceptance test procedures manual is used to perform acceptance testing of AISIM versions 4.2 and 5.0 This manual contains test procedures covering all functions of the AISIM system and a description of the expected results for each test.

This report presents the results of a study to establish parametric cost estimating relationships (CER's) for reliability and maintainability program tasks or groups of tasks; and to investigate the feasibility of determining cost-benefit indices. The specific tasks are defined in MIL-STD-785 and MIL-STD-470. The CER's were developed using multiple linear regression analysis (MLR) based on data from 23 projects of varying size and complexity. The cost-benefit investigation determined that the MLR techniques were also applicable to developing models for estimating MTBF gain as a measure of benefit.

This document describes the procedures for installing and conducting the installation and acceptance testing of the Hughes developed Automated Interactive Simulation Model (AISIM). Comprehensive testing of a system can be divided into three categories: component testing, integration testing, and demonstration testing. Component testing is intended to verify that each system component works properly. Such testing is the sole responsibility of the developers and, therefore, is beyond the scope of this document. Integration testing is intended to show that all the components operate together properly. This testing is planned and performed by the developers. Demonstration testing is intended to show that the system meets its functional requirements. This testing is broken into two phases: (1) installation testing and (2) acceptance testing. Hughes has developed the procedures for performing these tests and they are contained herein. Testing should be performed by personnel representing the contractor and the customer. This document also contains a description of the contents of the system tape - its files and organization. The procedures for loading this tape on the host computer and then building the AISIM system are described in detail., See also AD-A135 761.

This report contains the results of a study to determine the use and applicability to Air Force software acquisition managers of six quantitative software reliability models to a major command, control, communications, and intelligence (C3I) system. The scope of the study included the collection of software error data from an on going C3I project, fitting six software reliability models to the data, analyzing the predictions provided by the models, and developing conclusions, recommendations, and guidelines for software acquisition managers pertaining to the use and applicability of the models., See also Volume 1, AD-A138 196.

The Automated Interactive Simulation Model (AISIM) System provides the user with the ability to do high level simulation of complex operational and distributed data processing systems. The purpose of this manual is to provide the AISIM user with a comprehensive guide for the use of the system. The manual describes the use of the AISIM software primarily from the user's point of view. It contains information necessary to operate AISIM. This manual discusses the hardware and software environments for AISIM as well as the function of the AISIM software., See also AD-A135 760.