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Flexible encoder and decoder designs for low-density parity-check codesKopparthi, Sunitha January 1900 (has links)
Doctor of Philosophy / Department of Electrical and Computer Engineering / Don M. Gruenbacher / Future technologies such as cognitive radio require flexible and reliable hardware architectures that can be easily configured and adapted to varying coding parameters. The objective of this work is to develop a flexible hardware encoder and decoder for low-density parity-check (LDPC) codes. The design methodologies used for the implementation of a LDPC encoder and decoder are flexible in terms of parity-check matrix, code rate and code length. All these designs are implemented on a programmable chip and tested.
Encoder implementations of LDPC codes are optimized for area due to their high complexity. Such designs usually have relatively low data rate. Two new encoder designs are developed that achieve much higher data rates of up to 844 Mbps while requiring more area for implementation. Using structured LDPC codes decreases the encoding complexity and provides design flexibility. The architecture for an encoder is presented that adheres to the structured LDPC codes defined in the IEEE 802.16e standard.
A single encoder design is also developed that accommodates different code lengths and code rates and does not require re-synthesis of the design in order to change the encoding parameters. The flexible encoder design for structured LDPC codes is also implemented on a custom chip. The maximum coded data rate of the structured encoder is up to 844 Mbps and for a given code rate its value is independent of the code length.
An LDPC decoder is designed and its design methodology is generic. It is applicable to both structured and any randomly generated LDPC codes. The coded data rate of the decoder increases with the increase in the code length. The number of decoding iterations used for the decoding process plays an important role in determining the decoder performance and latency. This design validates the estimated codeword after every iteration and stops the decoding process when the correct codeword is estimated which saves power consumption. For a given parity-check matrix and signal-to-noise ratio, a procedure to find an optimum value of the maximum number of decoding iterations is presented that considers the affects of power, delay, and error performance.
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Experiment Demonstrating the Use of a WLAN for Data Telemetry from Small, Fast Moving NodesBamberger, R. J., Barrett, G. R., D’Amico, W. P., Lauss, M. H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper is a follow up to a paper presented at ITC 2002 entitled “Wireless Local Area Network
for Data Telemetry from Fast Moving Nodes” by R. J. Bamberger, G. R. Barrett, R. A. Nichols, and
J. L. Burbank of the Johns Hopkins University Applied Physics Laboratory, and M. H. Lauss of the
Yuma Test Center at the U.S. Army Yuma Proving Ground (YPG). In that paper, network-centric
data telemetry systems, specifically those based on commercial off- the-shelf (COTS) technologies
such as the IEEE 802.11b Wireless Local Area Network (WLAN), were offered as an improvement
over traditional frequency modulated (FM) data telemetry systems. The feasibility study of using
WLANs for data telemetry considered both the radio frequency (RF) link over extended ranges and
the effect due to Doppler shift. This paper describes an experiment designed to test those previous
analyses.
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AN AIRCRAFT T&E METHODOLOGY BASED ON THE IEEE 1451 FAMILY OF STANDARDSFernandes, Ronald, Graul, Michael, Koola, Paul, Garner, Mark, Jones, Charles H. 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper describes a methodology for aircraft T&E processes that exploits the advantages of
the IEEE 1451 family of standards, including the design, implementation, test, and maintenance
of instrumentation systems. The methodology includes the use of handheld and desktop
applications that support the design of sensor networks, commissioning of sensors, sensor health
monitoring, sensor plug-and-play capability, alarm management, and reports. The methodology
incorporates the use of existing instrumentation support systems that have traditionally been used
for aircraft T&E processes.
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Considerations for Deploying IEEE 1588 V2 in Network-Centric Data Acquisition and Telemetry SystemsNewton, Todd, Grim, Evan, Moodie, Myron 10 1900 (has links)
ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California / Network-centric architectures continue to gain acceptance in data acquisition and telemetry systems. Though networks by nature impose non-deterministic transit time of data through a given link, the IEEE 1588 standard provides a means to remove this jitter by distributing time messages to the data acquisition units themselves. But like all standards, they evolve over time. The same is true with IEEE 1588, which is releasing its second version later this year. This paper discusses the challenges of the first version of the IEEE 1588 standard that Version 2 set out to address, potential challenges with Version 2, and interoperability issues that may arise when incorporating a mixture of Version 1 and Version 2 devices.
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Wireless Sensor System for Airborne ApplicationsPellarin, Steve, Grossman, Hy, Musteric, Steven 10 1900 (has links)
ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California / Adding an instrumentation / telemetry system to a test article has historically required an intrusive installation. Power, wiring, and available space typically present significant challenges. There has been a long-standing need in the test and training community for a non-intrusive, flexible and modular instrumentation and telemetry system that can be installed on an aircraft or other test article without the need for permanent modifications. In addition, as available space in aircraft weapon bays, small weapons, and unmanned vehicles becomes a premium, the miniaturization of remote sensors and telemetry units becomes critical. This paper describes the current status of the Advanced Subminiature Telemetry System (ASMT) Initial Test Capability Project. It discusses the progress to date in fielding an operational, wireless sensor system that may be installed on the aircraft skin using an Electro-Cleavable adhesive as an alternative to conventional mounting methods. The wireless sensor utilizes the Wireless Communications Standard for Wireless Personal Area Network™ (WPAN™) IEEE 802.15 Working Group standard (commonly referred to as Bluetooth) to establish communication between the sensor and controller modules. Results of aircraft ground testing for EMI compatibility with aircraft systems will be presented. It is also expected that actual flight test results will be available by the time the paper goes to publication.
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WIRELESS SENSOR SYSTEM FOR AIRBORNE APPLICATIONSPellarin, Steve, Musteric, Steven 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Adding an instrumentation / telemetry system to a test article has historically required an
intrusive installation. Power, wiring, and available space typically present significant challenges.
There has been a long-standing need in the test and training community for a non-intrusive,
flexible and modular instrumentation and telemetry system that can be installed on an aircraft or
other test article without the need for permanent modifications. In addition, as available space in
aircraft weapon bays, small weapons, and unmanned vehicles becomes a premium, the
miniaturization of remote sensors and telemetry units becomes critical.
This paper describes the current status of the Advanced Subminiature Telemetry System
(ASMT) Initial Test Capability Project. It discusses the challenges that have been overcome in
developing a wireless sensor network system for use in an airborne test environment. These
include wireless sensor packaging design, selection of operating frequencies, COTS wireless
devices, batteries, system synchronization and data bandwidth calculations. The paper will also
document the progress to date including preliminary test results.
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OVERVIEW OF AN INTEGRATED INSTRUMENTATION DATA SYSTEM USED BY THE F-35 LIGHTNING II FLIGHT TEST PROGRAMVu, Doug, Berdugo, Albert 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The Joint Strike Fighter program is the largest DOD contract ever awarded. There are three F-35 Lightning II variations, each intended to meet the specific needs of the Air Force, Navy, Marine Corps, and U.S. Allies. The Data System required for this flight test program challenged the conventional ways used in instrumenting test aircraft. Typical data systems available today don’t provide the level of hardware and software integration required for today’s complex applications. For example, cockpit control panels, recording systems, TM transmitters, data acquisition systems and avionic bus interface units are all independent systems. Additionally, avionic bus catalogs, ground-based systems, and flight setup software have historically been independent components. This paper will describe the hardware and software components used by the F-35 flight test program to provide an integrated system. A special emphasis will be given to the methods used to accommodate rapid changes to the IEEE-1394B avionic bus catalog including the acquisition of that data, and the use of an IRIG-106 Chapter 10 distributed multiplexer / recorder system, which is being used simultaneously as a data acquisition system.
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DEVELOPMENT OF A NETWORK-CENTRIC DATA ACQUISITION, RECORDING, AND TELEMETRY SYSTEMMoodie, Myron, Newton, Todd, Abbott, Ben 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The growth of the Internet and the resulting increasing speeds and decreasing prices of network
equipment have spurred much interest in applying networks to flight test applications. However,
the best-effort, variable-latency nature of network transport causes challenges that must be
addressed to provide reliable data acquisition and timing performance. This paper describes the
major issues that must be addressed when designing and implementing real-time networking
applications. An overview of a recently implemented large-scale, network-centric data
acquisition, recording, and telemetry system for commercial flight test applications provides a
real-world example of what is currently achievable.
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EVALUATING IEEE 1588 IN A HOMOGENOUS SWITCHED NETWORK TEST ARTICLE SEGMENTWilmot, Sinbad, Corry, Diarmuid 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / At the 2007 iNet Technology Demonstrator multiple vendors are asked to participate to develop
and evaluate protocols for time synchronization, configuration identification and heterogeneous
data packet transfer. The iNet initiative from RCC is aimed at focusing and collating telemetry
network developments within the wider sphere of commercial and military network
developments. The KAM-500 is an inherently networked data-acquisition system offering
seamless gateways to many heterogeneous data sources, such as different sensor devices,
avionics-busses, networks and video sources. This paper offers insights into the impact of traffic
and network configuration on the performance of heterogeneous data acquisition in a
homogenous-switched network based a 1588 enabled controller module.
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A WIRELESS NETWORK-BASED RFNET SOLUTION FOR FLIGHT TESTXuming, Fan, Xiaoxian, Bai, Baoqiang, Zhao, Junmin, Zhang 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / An rfNET solution based on IEEE 802.11 wireless network is presented to perform one-way
remote transmission of airborne instrumentation data and multi-channel video images in
flight test by modifying the wireless network bridge and UDP protocol. Its architecture and
structure is introduced briefly and the results of ground transmission test and flight
demonstration transmission are provided. It also points out the major problems of this
solution for engineering application and their solutions.
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