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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

EFFECTS OF NON- LINEAR AMPLIFICATION ON N-GMSK AND N-FQPSK SIGNAL STATISTICS

Gonzalez, Maria C., Branner, George R. 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / Digital modulation schemes that are power and bandwidth efficient are highly desirable. After non-linear amplification has been done, signal modulation schemes having constant or quasi-constant envelopes are not as susceptible to spectral regrowth as those with non-constant envelopes. Since such distortion generates interference in the adjacent channels, the power operation of the amplifier in non-constant envelope modulations is typically backed off, resulting in systems with reduced power efficiency. On the other hand, constant envelope modulation may have different bandwidth spectra. This paper examines the statistical characteristics of N-GMSK and N-FQPSK [1] signals to assess the bandwidth efficiency in the presence of amplifier nonlinearities.
32

AN ONBOARD PROCESSOR FOR FLIGHT TEST DATA ACQUISITION SYSTEMS

Wegener, John A., Blase, Gordon A. 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Today’s flight test programs are experiencing increasing demands for a greater number of high-rate digital parameters, competition for spectrum space, and a need for operational flexibility in flight test instrumentation. These demands must be met while meeting schedule and budget constraints. To address these various needs, the Boeing Integrated Defense System (IDS) Flight Test Instrumentation group in St. Louis has developed an onboard processing capability for use with airborne instrumentation data collection systems. This includes a first-generation Onboard Processor (OBP) which has been successfully used on the F/A-18E/F Super Hornet flight test program for four years, and which provides a throughput of 5 Mbytes/s and a processing capability of 480 Mflops (floating-point operations per second). Boeing IDS Flight Test is also currently developing a second generation OBP which features greatly enhanced input and output flexibility and algorithm programmability, and is targeted to provide a throughput of 160 Mbytes/s with a processing capability of 16 Gflops. This paper describes these onboard processing capabilities and their benefits.
33

DATA COMPRESSION STATISTICS AND IMPLICATIONS

Horan, Sheila 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Bandwidth is a precious commodity. In order to make the best use of what is available, better modulation schemes need to be developed, or less data needs to be sent. This paper will investigate the option of sending less data via data compression. The structure and the entropy of the data determine how much lossless compression can be obtained for a given set of data. This paper shows the data structure and entropy for several actual telemetry data sets and the resulting lossless compression obtainable using data compression techniques.
34

TELEMETRY RF SIGNAL BANDWIDTH; DEFINITIONS AND STANDARDS

Law, Eugene L. 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / This paper will present and compare several definitions of telemetry radio frequency (RF) signal bandwidth. Measured spectra for different signals will be presented. The bandwidths of these signals will then be determined and measurement methods will be discussed. This discussion will include the effects of spectrum analyzer resolution bandwidth, video bandwidth and detector type. Finally, a proposed spectral mask will be discussed. This spectral mask can be used to calculate the required attenuation for a given frequency offset from the center frequency. The required attenuation is a function of the the bit rate or maximum frequency of interest and the transmitter power. This spectral mask is proposed to be part of the next edition of the Telemetry Standards, Inter-Range Instrumentation Group (IRIG) Standard 106.
35

RADIO FREQUENCY PATH CHARACTERIZATION FOR WIDE BAND QUADRATURE AMPLITUDE MODULATION

Bracht, Roger 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / Remote, high speed, high explosive wave front monitoring requires very high bandwidth telemetry to allow transmission of diagnostic data before the explosion destroys the sensor system itself. The main motivation for this study is that no known existing implementation of this sort has been applied to realistic weapons environments. These facts have prompted the research and gathering of data that can be used to extrapolate towards finding the best modulation method for this application. In addition to research of similar existing analysis and testing operations, data was recently captured from a Joint Test Assembly (JTA) Air Launched Cruise Missile (ALCM) flight.
36

IPCM Telemetry System: Experimental Results

Carvalho, Marco Aurélio 10 1900 (has links)
ITC/USA 2015 Conference Proceedings / The Fifty-First Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2015 / Bally's Hotel & Convention Center, Las Vegas, NV / The aeronautical industries have been suffering financial cutbacks and the market has to face new challenges associated with new companies. Telemetry community has been facing the increase of the electromagnetic spectrum usage for a variety of applications (e.g. 4G), after all telemetry is everywhere. In view of these issues and focused on the inherent requirements of the Flight Test application, the IPEV R&D group proposes the iPCM Telemetry architecture as solution for the existing reliability and bandwidth issues associated with the telemetry link. In this article, as a proof-of-concept of the iPCM architecture, it has been performed an experimental assembly. The results demonstrate the iPCM's ability to regenerate corrupted data providing the required data integrity and reliability, besides the capability to dynamically select the FTI transmitted parameter list to optimize the bandwidth link.
37

Multimedia Codec Evaluation and Overview

Dernaika, Ghina, Khavtasi, Sophia January 2007 (has links)
Movies, songs, conferences, video streams and other multimedia services are spreading in everybody’s life, needs and work. Different types of audio and video codecs of various qualities appear to be used for different purposes. However, each codec can be suitable for a special usage, as for example a codec that can be use for high quality film may not be suitable for streaming it into network. The main purpose of this thesis is to compare the performance of different codecs in one particular scenario and indicate which codec performance is the best. The thesis work includes the investigation of several codec aspects (audio and video) and problems related to choosing a multimedia codec (coder/decoder) suitable for large-scale multimedia distribution over the Internet. More specifically, the work focuses on various features of modern media codecs, compares them and finds the best application for each of them. Furthermore, the thesis provides an overview of available research results related to this work and codec comparison tables for codecs and their features. Additionally, as part of this work, a testbed was developed to measure the performance of codecs when used to stream media over a network. The testbed enabled the collection of various QoS parameters, such as bandwidth usage and burst, size for each codec considered in this thesis. / Address: Minervavägen 22A, Room 2, 371 41 Karlskrona, sweden. Cel: +46706456674
38

Adaptive space diversity and ring coding for multicarrier CDMA over mobile radio channels

Uribeetxeberria, Roberto January 2001 (has links)
No description available.
39

Optimisation of spectrum utilisation for mobile communication systems

Mazharov, Konstantin January 1999 (has links)
No description available.
40

Compression of integral three-dimensional television pictures

Forman, Matthew Charles January 2000 (has links)
No description available.

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