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1
Ahn, Seung Choon. "Variable threshold detection with weighted PCM signal transmitted over Gussian channel." Ohio : Ohio University, 1986. http://www.ohiolink.edu/etd/view.cgi?ohiou1183126123.
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Borgen, Gary. "MICROCONTROLLER BASED PCM ENCODERS FOR TELEMETRY INSTRUMENTATION." International Foundation for Telemetering, 2005. http://hdl.handle.net/10150/604920.
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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<br>Pulse Code Modulation (PCM) Encoders used in Telemetry Instrumentation systems have traditionally been implemented using sequencer or state-machine based micro-architectures with distributed control and signal acquisition components. This architecture requires the use of many discrete electronic components and custom micro-code programming or state machine development for the control of the systems. The advent of relatively high-speed microcontrollers with embedded signal acquisition subsystems has brought about the ability to implement highly integrated PCM Encoder systems using fewer components and standardized programming methods. This paper will discuss sequencer based PCM encoders for background and then introduce the concept of Microcontroller Based PCM Encoders for Telemetry Instrumentation. Specific design examples will be introduced. Advantages and disadvantages of the two techniques will be discussed.
3
Svensson, Ake, and Michael Maoz. "HIGH SHOCK, COMPUTERIZED, MINIATURE, AIRBORNE PCM/FM TELEMETRY SYSTEM." International Foundation for Telemetering, 1989. http://hdl.handle.net/10150/614501.
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International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, California<br>Aydin Vector Division has developed and manufactured an airborne, high shock, wideband FM/FM telemetry system for Saab Missiles AB in Sweden. This system was presented in the ITC Proceedings of 1988, Volume XXIV, pp 71-84 (Ref [1]). Three such systems were supplied. Saab Missiles AB also awarded Aydin Vector Division with an additional order for a larger number of high shock, computer based, specially designed, miniature PCM/FM airborne telemetry systems. These systems were developed, manufactured and supplied to Saab Missiles AB, and have been extensively and successfully used in the Swedish program. The PCM/FM telemetry package described in this paper was used for the system testing and the firing trials program of a mortar projectile, where the measurement requirements included micro processor interfaces, as well as a high amount of analog and bi-level data channels. The paper covers the specifications of the PCM/FM system mentioned above, the concept that was used to meet these specifications, the system’s mechanical and electrical design, the packaging technique and some of the test results.
4
Elsabrouty, Maha. "Receiver-based packet loss concealment for pulse code modulation (PCM G.711) coders." Thesis, University of Ottawa (Canada), 2002. http://hdl.handle.net/10393/6306.
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Voice-over-IP (VoIP), the transmission of packetized voice over IP networks, is gaining much attention as a possible alternative to conventional Public Switched Telephone Networks (PSTN). However, impairments present on IP networks, namely jitter, delay and channel errors can lead to the loss of packets at the receiving end. This packet loss degrades the speech quality. Model-based coders, especially G.729-A and G.723.1 International Telecommunication Union (ITU-T) Standards, have been extensively used for speech coding over IP networks because of their inherent ability to recover from erasure. Their built-in packet loss concealment makes their quality drop slowly with increasing amount of packet loss. However, their memory makes the transition from the concealed state to the correct state require a few frames and they actually tend to corrupt a few good packets before recovery as a result of a phenomenon known as "State Error". On the other hand, Pulse Code Modulation (PCM), although having a higher score than G.729 and G.723 in the periods of normal operations, does not have the ability to conceal erasure and the quality of speech during loss periods drops dramatically. Yet it can recover from packet loss more rapidly than model-based coders since the first speech sample in the first good packet restores speech to its original quality. The goal of this work is to develop a Packet Loss Concealment (PLC) algorithm to provide the G.711 PCM coders with the required ability to conceal erasure and maintain a high score of user satisfaction. This algorithm uses a receiver-based prediction model to develop an estimate of the missing speech segments.
5
Tate, Jeffrey J. "Automating Signal Conditioning Setup Through Integration with Sensor Information." International Foundation for Telemetering, 1997. http://hdl.handle.net/10150/607535.
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International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada<br>Caterpillar Inc. has been testing construction and mining equipment using Computerized
Analysis Vans for two decades. During our latest van upgrade, we chose to move to
PCM/FM from FM/FM mainly to increase the channel count. We also replaced our old
signal conditioning that used span and balance potentiometers with computer
programmable signal conditioning. This new signal conditioning requires that the gain and
balance point be calculated for every channel on each test. The formulas for these
calculations depend on the sensor, the signal conditioning card used, and the test
requirements. Due to the number and variety of machines tested at the Caterpillar Proving
Grounds, these calculations needed to be automated. Using a few initial parameters and
the information from our sensor calibration database, each channel’s balance point, gain,
and expected slope are calculated. This system has increased productivity, accuracy, and
consistency over manually calculating these parameters. This paper covers the sensor
database, the calculated parameters and an overview of the way the system works.
6
PENHARLOW, DAVID. "MICROMINIATURE DISTRIBUTED DATA ACQUISITION SYSTEM." International Foundation for Telemetering, 1990. http://hdl.handle.net/10150/613485.
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International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, Nevada<br>The new generation of advanced tactical aircraft and missiles places unique demands on the electronic and mechanical designs for flight test instrumentation, high bit rates, operating temperature range and system interconnect wiring requirements.
This paper describes a microminiature PCM distributed data acquisition system with integral signal conditioning (MMSC) which has been used in advanced aircraft and missile flight testing. The MMSC system is constructed from microminiature, stackable modules which allow the user to reconfigure the system as the requirements change. A second system is also described which uses the same circuitry in hermetic hybrid packages on plug-in circuit boards.
7
Gaddis, William R. Jr, and Sawn Sandland. "AATIS AND CAIS DATA RECORDING." International Foundation for Telemetering, 1993. http://hdl.handle.net/10150/608876.
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International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada<br>DOD flight test centers need affordable, small-format, flight-qualified digital
instrumentation recording solutions to support existing and future flight testing. The
Advanced Airborne Test Instrumentation System (AATIS) is today's primary data
acquisition system at the Air Force Flight Test Center (AFFTC). Digital Recorder
(DR) 1995 is planned to provide full support for AATIS output capabilities and satisfy
initial recording requirements for the Common Airborne Instrumentation System
(CAIS). The follow-on to the AATIS, the CAIS is a tri-service development to satisfy
future DOD flight test data acquisition requirements. DR 2000 is planned as the future
recording solution for CAIS and will be able to fully satisfy the 50 Mbps recording
requirement. In the developments of DR 1995 and DR 2000, commonality and
interoperability have emerged as significant issues. This paper presents an overview
of these recording solutions and examines commonality and interoperability issues.
8
Morgan, Jon, and Charles H. Jones. "PCM Backfill: Providing PCM to the Control Room Without Dropouts." International Foundation for Telemetering, 2014. http://hdl.handle.net/10150/577490.
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ITC/USA 2014 Conference Proceedings / The Fiftieth Annual International Telemetering Conference and Technical Exhibition / October 20-23, 2014 / Town and Country Resort & Convention Center, San Diego, CA<br>One of the initial control room capabilities to be demonstrated by iNET program is the ability to provide data displays in the control room that do not contain data dropouts. This concept is called PCM Backfill where PCM data is both transmitted via traditional SST and recorded onboard via an iNET compatible recorder. When data dropouts occur, data requests are made over the telemetry network to the recorder for the missing portions of the PCM data stream. The retrieved data is sent over the telemetry network to the backfill application and ultimately delivered to a pristine data display. The integration of traditional SST and the PCM Backfill capability provides both real-time safety of flight data side-by-side with pristine data suitable for advanced analysis.
9
Ng, Sunny, Mei Y. Wei, Austin Somes, Mich Aoyagi, and Joe Leung. "REAL-TIME DATA SERVER-CLIENT SYSTEM FOR THE NEAR REAL-TIME RESEARCH ANALYSIS OF ENSEMBLE DATA." International Foundation for Telemetering, 1998. http://hdl.handle.net/10150/609671.
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International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California<br>This paper describes a distributed network client-server system developed for researchers to perform real-time or near-real-time analyses on ensembles of telemetry data previously done in post-flight. The client-server software approach provides extensible computing and real-time access to data at multiple remote client sites. Researchers at remote sites can share similar information as those at the test site. The system has been used successfully in numerous commercial, academic and NASA wide aircraft flight testing.
10
Berdugo, Albert, and William G. Ricker. "A NEW 1553 ALL-BUS INSTRUMENTATION MONITOR." International Foundation for Telemetering, 1990. http://hdl.handle.net/10150/613782.
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International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, Nevada<br>Increased data throughput demands in military and avionics systems has led to the development of an advanced, All-Bus MIL-STD-1553 Instrumentation Monitor. This paper discusses an airborne unit which acquires the information from up to 8 dual-redundant buses, and formats the data for telemetry, recording or real-time analysis according to the requirements of IRIG-106-86, Chapter 8.
The ALBUS-1553 acquires all or selected 1553 messages which are formatted into IRIG-compatible serial data stream outputs. Data is time tagged to microsecond resolution. The unit selectively transmits entire or partial 1553 messages under program control. This results in reduced transmission bandwidth if prior knowledge of 1553 traffic is known.
The ALBUS also encodes analog voice inputs, discrete userword inputs and multiplexed analog (overhead) inputs. The unit is provided in a ruggedized airborne housing utilizing standard ATR packaging,
11
Eccles, Lee, Michael O’Brien, and William Anderson. "DATA ACQUISITION SYSTEM FOR AIRCRAFT QUALIFICATION." International Foundation for Telemetering, 1986. http://hdl.handle.net/10150/615566.
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International Telemetering Conference Proceedings / October 13-16, 1986 / Riviera Hotel, Las Vegas, Nevada<br>The Boeing Commercial Airplane Company presently uses an Airborne Data Analysis and Monitor System (ADAMS) to support extensive qualification testing on new and modified commercial aircraft. The ADAMS system consists of subsystems controlled by independent processors which preprocess serial PCM data, perform application-specific processing, provide graphic display of data, and manage mass storage resources. Setup and control information is passed between processors using the Ethernet protocol on a fiber optic network. Tagged data is passed between processors using a data bus with networking characteristics. During qualification tests, data are dynamically selected, analyses performed, and results recorded. Decisions to proceed or repeat tests are made in real time on the aircraft.
Instrumentation in present aircraft includes up to 3700 sensors, with projections for 5750 sensors in the next generation. Concurrently, data throughput rates are increasing, and data preprocessing requirements are becoming more complex. Fairchild Weston Systems, Inc., under contract to Boeing, has developed an Acquisition Interface Assembly (AIA) which accepts multiple streams of PCM data, controls recording and playback on analog tape, performs high speed data preprocessing, and distributes the data to the other ADAMS subsystems. The AIA processes one to three streams in any of the standard IRIG PCM formats using programmable bit, frame and subframe synchronizers. Data from ARINC buses with embedded measurement labels, bus ID’s, and time tags may also be processed by the AIA. Preprocessing is accomplished by two high-performance Distributed Processing Units (DPU) operating in either pipeline or parallel environments. The DPU’s perform concatenation functions, number system conversions, engineering unit conversions, and data tagging for distribution to the ADAMS system. Time information, from either a time code generator or tape playback, may be merged with data
with a 0.1 msec resolution. Control and status functions are coordinated by an embedded processor, and are accessible to other ADAMS processors via both the Ethernet interface and a local operator’s terminal.
Because the AIA assembly is used in aircraft, the entire functional capability has been packaged in a 14-inch high, rack-mountable chassis with EMI shielding. The unit has been designed for high temperature, high altitude, vibrating environments. The AIA will be a key element in aircraft qualification testing at Boeing well into the next generation of airframes, and specification, design, development, and implementation of the AIA has been carried out with the significance of that fact in mind.
12
Papich, William J. "THE USE OF TELEMETRY IN AN ELECTROMAGNETIC TEST ENVIRONMENT." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/607292.
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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada<br>The U.S. Army Redstone Technical Test Center (RTTC) uses telemetry as a vital part of
its data acquisition and analysis for electromagnetic environmental effects developmental
testing of U.S. Army weapon systems. Testing in an electromagnetic environment poses
several unique challenges. These challenges have resulted in the development of highly
customized telemetry and data acquisition systems. This paper discusses the design and
integration of past and current telemetry needs to incorporate real-time or near real-time
simulations or scene generations into the testing process.
13
Afiomah, Stephen U. "A decision-directed-detection scheme for PCM systems in a noisy environment." Ohio : Ohio University, 1986. http://www.ohiolink.edu/etd/view.cgi?ohiou1183125570.
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Filho, Nelson Whitaker. "Aircraft Distance Measurement System." International Foundation for Telemetering, 1994. http://hdl.handle.net/10150/611674.
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International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California<br>The Aircraft Distance Measurement System (ADMS) could be used in Flight Test application to determine the aircraft position and speed during takeoff, landing and acceleration-stop performance test within runway limits using a microwave link.
15
Knoebel, Robert, and Albert Berdugo. "“CAIS GROUND SUPPORT EQUIPMENT USING A LOW COST, PC-BASED PLATFORM”." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/607589.
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International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California<br>The Common Airborne Instrumentation System (CAIS) was developed under the auspices
of the Department of Defense to promote standardization, commonality, and
interoperability among flight test instrumentation. The central characteristic of CAIS is a
common suite of equipment used across service boundaries and in many airframe and
weapon systems.
The CAIS system has many advanced capabilities which must be tested during ground
support and system test. There is a need for a common set of low cost, highly capable
ground support hardware and software tools to facilitate these tasks.
The ground support system should combine commonly available PC-based telemetry tools
with unique devices needed for CAIS applications (such as CAIS Bus Emulator, CAIS
Hardware Simulator, etc.). An integrated software suite is imperative to support this
equipment.
A CAIS Ground Support Unit (GSU) has been developed to promote these CAIS goals.
This paper presents the capabilities and features of a PC-based CAIS GSU, emphasizing
those features that are unique to CAIS. Hardware tools developed to provide CAIS Bus
Emulation and CAIS Hardware Simulation are also described.
16
Knudtson, Kevin, Alice Park, Bob Downing, Jack Sheldon, Robert Harvey, and April Norcross. "The Western Aeronautical Test Range Chapter 10 Tools." International Foundation for Telemetering, 2011. http://hdl.handle.net/10150/595770.
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ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada<br>The Western Aeronautical Test Range (WATR) staff at the NASA Dryden Flight Research Center is developing a translation software called Chapter 10 Tools in response to challenges posed by post-flight processing data files originating from various on-board digital recorders that follow the Range Commanders Council Inter-Range Instrumentation Group (IRIG) 106 Chapter 10 Digital Recording Standard but use differing interpretations of the Standard. The software will read the date files regardless of the vendor implementation of the source recorder, displaying data, identifying and correcting errors, and producing a data file that can be successfully processed post-flight.
17
Grace, Thomas. "COMMON AIRBORNE INSTRUMENTATION SYSTEM; A FRESH LOOK." International Foundation for Telemetering, 2001. http://hdl.handle.net/10150/606475.
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International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada<br>The US Government originally funded the development of the Common Airborne Instrumentation
System (CAIS) to address industry-wide compatibility, maintenance, and commonality issues. Although
initially targeted for US Department of Defense (DoD) programs, CAIS is also being used throughout
the world in many commercial applications. This paper provides a fresh look at the evolution of the
CAIS concept starting with some historical background of the CAIS Program, an overview of the CAIS
System Architecture and recent trends in the use of “Commercial Off The Shelf (COTS)” products and
technology.
18
Billings, Don, Mei Wei, Joseph Leung, Michio Aoyagi, Fred Shigemoto, and Rob Honeyman. "REAL-TIME INTEGRATION OF RADAR INFORMATION, AND GROUND AND RADIOSONDE METEOROLOGY WITH FLIGHT RESEARCH DATA." International Foundation for Telemetering, 1998. http://hdl.handle.net/10150/607368.
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International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California<br>Although PCM/TDM framed data is one of the most prevalent formats handled by flight
test ranges, it is often required to acquire and process other types. Examples of such non-standard
data types are radar position information and meteorological data from both
ground based and radiosonde systems. To facilitate the process and management of such
non-standard data types, a micro-processor based system was developed to acquire and
transform them into a standard PCM/TDM data frame. This obviated the expense of
developing additional special software and hardware to handle such non-standard data
types.
19
Knudtson, Kevin M., and Randy Glass. "DIGITAL VOICE DECODING IN TODAY'S TELEMETRY SYSTEM." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/607327.
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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada<br>Today’s telemetry systems can reduce spectrum demand and maintain secure voice
by encoding analog voice into digital data using; Continuously Variable Slope Delta
Modulation ( CVSD ) format and imbedding it into a telemetry stream. The model CSC-0390 DvD system is an excellent choice in decoding digital voice, designed with
flexibility, efficiency, and simplicity in mind. Flexibility in design brings forth a
capability of operating on a wide variety of telemetry systems and data formats without
any specialized interfaces. The utilization of 74HC series circuit technology makes this
DvD system efficient in design, low cost, and lower power consumption. In addition the
front panel display and control function is also is an example of Simplicity in design and
operation.
20
Alagha, Nader Sheikholeslami. "Modulation, pre-equalization and pulse shaping for PCM voiceband channels." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38277.
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For the past few decades, analog voiceband modems have been used extensively to carry digital information over the Public Switched Telephone Network (PSTN). Conventional voiceband modems treat the PSTN as an analog communication channel. However, today's PSTN is mostly a digital network except for the basic telephone services provided via analog subscriber lines. The conventional model of analog voiceband channels is no longer adequate to characterize the physical connection between terminals with direct digital access to the network and voiceband modems connected to analog subscriber lines. Such a connection requires a different model in each direction. There are now international modem standards which support rates of up to 56 kbits/s for the down-stream channel.<br>This dissertation examines the more challenging part of the voiceband communication channel, i.e., the up-stream direction connecting an analog subscriber to the digital network. The major source of distortion on the up-stream channel is quantization error caused by analog-to-digital conversion performed as part of the encoding to Pulse-Code Modulation (PCM) process. A bandpass filter prior to the PCM encoder restricts the bandwidth while the sampling rate of the PCM encoder is predetermined by the network. Signalling in the presence of such constraints lead to theoretical problems as well as practical concerns in modem design.<br>Communication models that characterize PCM voiceband channels are developed. We investigate modulation design and related issues including index mapping, constellation design and constellation probability assignment to match the pre-determined structure of the detector at the receiver, i.e., the PCM encoder at the central office.<br>We develop a framework for transmitter structures that can avoid or reduce Inter-Symbol Interference (ISI) at the receiver in order to sidestep the limited bandwidth of the up-stream channels and the fixed sampling rate of the up-stream channel. Techniques employed include linear filtering, spectral shaping and precoding to reduce the ISI, while limiting the average transmitted signal power. A filterbank structure for pre-equalizing channels with spectral nulls is also described.<br>A new method for pulse shaping design is proposed. The new pulse shaping filters provide a compatible design that can be used for the up-stream PCM channel as well as to the cascade of the up-stream and the down-stream channels.<br>Compared to conventional modem design, the proposed modulation and pre-equalization techniques together allow for an increase of the data transmission rates in the up-stream direction of up to 50%.
21
Dicken, L. W., and K. Jenkins. "Pulse Code Modulated Flight Termination Receiver." International Foundation for Telemetering, 1995. http://hdl.handle.net/10150/611593.
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International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada<br>Flight Termination is a control action that takes place when missiles or targets violate estabished safety criteria. The flight termination receiver, part of a ground to air control loop, is characterised by high system integrity and dedication to recovering and decoding the command signals. The paper describes the factors that have influenced the design and build of a robust Pulse Code Modulation Flight Termination Receiver for use on UK Trial Ranges. This work has been carried out with the support of UK MoD(PE), A ARM 51, on contract number A ARM 13b/224.
22
Lum, Randall M. G. "Differential pulse code modulation data compression." Scholarly Commons, 1989. https://scholarlycommons.pacific.edu/uop_etds/2181.
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With the requirement to store and transmit information efficiently, an ever increasing number of uses of data compression techniques have been generated in diverse fields such as television, surveillance, remote sensing, medical processing, office automation, and robotics. Rapid increases in processing capabilities and the speed of complex integrated circuits make data compression techniques a prime candidate for application in the areas mentioned above. This report addresses, from a theoretical viewpoint, three major data compression techniques, Pixel Coding, Predictive Coding, and Transform Coding. It begins with a project description and continues with data compression techniques, focusing on Differential Pulse Code Modulation.
23
Daqing, Huang. "Programming Code-Modulator and Demodulation-Decoder Suited to PCM Systems." International Foundation for Telemetering, 1989. http://hdl.handle.net/10150/614707.
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International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, California<br>In order to suit the development of computer telemetry systems, we have developed the intelligent code-modulator and demodulation-decoder. In hardware, they consist of a monolithic processor and some high-integrated devices. Different code or decode ways and several subcarrier modulation or demodulation systems can be varied by carrying out corresponding software programs. In this paper, the equipments' hardware constructions and software cnarts and their main principles are presented.
24
Baughman, James E. "A High Speed Miniature Pulse Code Modulation System." International Foundation for Telemetering, 1989. http://hdl.handle.net/10150/614639.
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International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, California<br>Increasing speed and complexity of guidance and target acquisition systems being developed for SDI missile interceptors mandate new performance standards for today's airborne telemetry systems. High bandwidth video data merged with a myriad of high sample rate analog and digital channels have pushed bit rates to 10 MBPS (Mega Bits Per Second) and beyond. These bit rates which are an order of magnitude beyond most telemetry systems in use today, result in the need for a new architecture which facilitates data transfer at these higher rates.
25
Navickas, T. A., and S. G. Jones. "PULSE CODE MODULATION DATA COMPRESSION FOR AUTOMATED TEST EQUIPMENT." International Foundation for Telemetering, 1991. http://hdl.handle.net/10150/612065.
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International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada<br>Development of automated test equipment for an advanced telemetry system requires
continuous monitoring of PCM data while exercising telemetry inputs. This
requirements leads to a large amount of data that needs to be stored and later analyzed.
For example, a data stream of 4 Mbits/s and a test time of thirty minutes would yield
900 Mbytes of raw data. With this raw data, information needs to be stored to
correlate the raw data to the test stimulus. This leads to a total of 1.8 Gb of data to be
stored and analyzed. There is no method to analyze this amount of data in a reasonable
time. A data compression method is needed to reduce the amount of data collected to a
reasonable amount.
The solution to the problem was data reduction. Data reduction was accomplished by
real time limit checking, time stamping, and smart software. Limit checking was
accomplished by an eight state finite state machine and four compression algorithms.
Time stamping was needed to correlate stimulus to the appropriate output for data
reconstruction. The software was written in the C programming language with a DOS
extender used to allow it to run in extended mode. A 94 - 98% compression in the
amount of data gathered was accomplished using this method.
26
Collaer, Marcia Lee. "IMAGE DATA COMPRESSION: DIFFERENTIAL PULSE CODE MODULATION OF TOMOGRAPHIC PROJECTIONS." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/291412.
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Ma, Kuang-Hua. "Image compression using a double differential pulse code modulation technique (DPCM/DPCM." Ohio : Ohio University, 1996. http://www.ohiolink.edu/etd/view.cgi?ohiou1178215120.
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Wong, K. H. J. "Adaptive differential pulse code modulation and sub-band coding of speech signals." Thesis, University of Southampton, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380170.
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See, Chun Kit. "Hybrid pulse interval modulation-code-division multiple-access for optical wireless communications." Thesis, Sheffield Hallam University, 2003. http://shura.shu.ac.uk/20340/.
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The work in this thesis investigates the properties of the IR diffuse wireless link with regard to: the use of sets of signature sequences with good message separation properties (hence providing low BER), the suitability of a hPIM-CDMA scheme for the IR diffuse wireless systems under the constraint of eye safety regulations (i.e. when all users are transmitting simultaneously), the quality of message separation due to multipath propagation. The suitability of current DS-CDMA systems using other modulation techniques are also investigated and compared with hPIM-CDMA for the performances in power efficiency, data throughput enhancement and error rate. A new algorithm has also been proposed for generating large sets of (n,3,1,1)OOC practically with reduced computation time. The algorithm introduces five conditions that are well refined and help in speeding up the code construction process. Results for elapsed computation times for constructing the codes using the proposed algorithm are compared with theory and show a significant achievement. The models for hPIM-CDMA and hPPM-CDMA systems, which were based on passive devices only, were also studied. The technique used in hPIM-CDMA, which uses a variable and shorter symbol duration, to achieve higher data throughput is presented in detail. An in-depth analysis of the BER performance was presented and results obtained show that a lower BER and higher data throughput can be achieved. A corrected BER expression for the hPPM-CDMA was presented and the justification for this detailed. The analyses also show that for DS-CDMA systems using certain sets of signature sequences, the BER performance cannot be approximated by a Gaussian function.
30
Yoshida, K. "Speech coding by adaptive differential pulse code modulation with adaptive bit allocation." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37905.
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31
Johnson, Bruce. "Telemetry Receive/Record & Re-Radiation Pod." International Foundation for Telemetering, 2014. http://hdl.handle.net/10150/577391.
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ITC/USA 2014 Conference Proceedings / The Fiftieth Annual International Telemetering Conference and Technical Exhibition / October 20-23, 2014 / Town and Country Resort & Convention Center, San Diego, CA<br>This paper discusses the mission needs, design/development, and testing of the (L, S & C Band) Telemetry Receive/Record & Re-Radiation pod.
32
Cooperwood, Michael Vonshay. "Analysis and performance comparison of adaptive differential pulse code modulation data compression systems." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA307823.
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Baker, Kenneth R. "Importance sampling simulation of free-space optical APD pulse position modulation receivers." Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06062008-172207/.
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Skrzypczak, Alexandre, Grégory Blanc, and Bournault Tangi Le. "Combining a Reed-Solomon Block Code with a Blind Equalizer: Synchronization and Bit Error Rate Performance." International Foundation for Telemetering, 2015. http://hdl.handle.net/10150/596403.
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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<br>The performance of telemetry systems may be strongly affected by diverse sources of perturbations. Among them, multipath channels and transmission noise are the most critical. While the effects due to the multipath channels can be attenuated thanks to equalization, the effects of the noise are limited if forward error correction is used. This paper first proves that the combination of blind equalization and forward error correction can strongly improve bit error rates. The other objective of the paper is to show that reasonably powerful codes like Reed-Solomon codes are sufficient to enable quasi-error free transmissions in a large majority of propagation channel scenarios.
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Ferreira, Alisson da ConceiÃÃo. "Estudo numÃrico do acoplador duplo simÃtrico de fibras Ãpticas operando com PPM e PAM para obtenÃÃo de portas lÃgicas." Universidade Federal do CearÃ, 2008. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2365.
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CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior<br>Neste trabalho, foram investigadas as caracterÃsticas de operaÃÃo de um Acoplador Direcional NÃo-Linear(NLDC) Duplo SimÃtrico, trabalhando com pulsos de , em duas diferentes aplicaÃÃes: ObtenÃÃo de portas lÃgicas E e OU, sob ModulaÃÃo Por PosiÃÃo de Pulsos (PPM); obtenÃÃo de portas lÃgicas E e OU, sob ModulaÃÃo Por Amplitude de Pulsos (PAM). A investigaÃÃo à realizada, atravÃs de simulaÃÃes numÃricas, utilizando-se do mÃtodo de Runge Kutta de quarta ordem. Na primeira aplicaÃÃo, à analisada a possibilidade da realizaÃÃo de operaÃÃes lÃgicas pelo Acoplador Direcional NÃo-Linear (NLDC) Duplo SimÃtrico sem perda. Considerando a operaÃÃo das portas lÃgicas, foram utilizadas as quatro possÃveis combinaÃÃes para dois pulsos, nas fibras 1 e 2, modulados pela posiÃÃo temporal (PPM) nos nÃveis lÃgicos 0 ou 1. Foram investigados os efeitos de uma variaÃÃo no parÃmetro de ajuste da modulaÃÃo PPM, ou seja, no deslocamento inicial do pulso em relaÃÃo ao pulso referencial, ou informaÃÃo nÃo modulada, e na diferenÃa de fase entre os pulsos sÃlitons fundamentais de entrada devidamente modulados. Na segunda aplicaÃÃo, o NLDC duplo simÃtrico à submetido à modulaÃÃo PAM, utilizando-se tambÃm, das quatro combinaÃÃes possÃveis para os dois pulsos, nas fibras de entrada. Foram investigados os efeitos da variaÃÃo no parÃmetro de ajuste da modulaÃÃo PAM na amplitude inicial do pulso em relaÃÃo à amplitude de referÃncia, ou sinal sem modulaÃÃo, e tambÃm observada a amplitude de saÃda modulada versus uma diferenÃa de fase entre os pulsos sÃlitons fundamentais de entrada devidamente modulados. Nas duas aplicaÃÃes foram obtidas portas lÃgicas E e OU.<br>In this work, the performance study of a Symmetric Dual-Core Non-Linear Directional Coupler (NLDC), working with pulses of , in two different applications have been investigated: accomplishment of logical gates AND and OR, under Pulse Position Modulation (PPM); accomplishment of logical gates AND and OR, under Pulse Amplitude Modulation (PAM). The investigation is based in a numerical simulation study, using the fourth order Runge Kutta numerical method. In the first application, the possibility of the accomplishment of logical operations by Symmetric Dual-Core Non-Linear Directional Coupler (NLDC) without loss is analyzed. Considering the operation of the logical gates, the four possible combinations for two pulses, on the input fibers, modulated by the temporal PPM in the logical levels 0 or 1, were used. The effects of a variation in the coding parameter offset of the PPM modulation, that is, in the displacement of the input pulse relative to the reference time level, was investigated. In the second application, the symmetric dual-core NLDC is submitted to PAM modulation, using the four possible combinations for two pulses on the input fibers, were used, as well. The effects of a variation in the coding parameter offset of the PAM modulation relative to the reference amplitude, was investigated. The modulated output amplitude versus a phase difference between the input pulses , was also studied. On the two applications, logical gates AND and OR was observed.
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Zichy, Michael Andrew. "[Sigma Delta] Quantization with the hexagon norm in C /." Electronic version (PDF), 2006. http://dl.uncw.edu/etd/2006/zichym/michaelzichy.pdf.
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Šiška, Martin. "Impulzové modulace." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220215.
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This work deals with the analysis of pulse modulation issues, work is divided into six chapters. The first chapter of the thesis deals with pulse modulations as a whole. It explains the concept of modulation, the distinction between analog and digital modulation, and there is the basic classification of pulse modulation done. The second chapter focuses on the issue of non-quantized pulse modulation. For each modulation belonging to this group is verbally and graphically explains the principle of its activities. In the third chapter, which is similar to the second chapter, the work focuses on quantized pulse modulation. Again, each of these modulations explained its basic principle. It is also in this chapter outlines the design models in Matlab-Simulink. The fourth chapter presents calculations and tables with calculated values needed for simulations. In the fifth chapter, a comparison waveforms. It contains a discussion about the dependence of modulation on their parameters, parameters of the input signal and the sampling frequency. In the final sixth chapter deals with the early design concepts and detailed diagrams for the production of demonstration products.
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Cirineo, Tony. "Doppler Video Signal Conditioning, Theory of Operation." International Foundation for Telemetering, 1996. http://hdl.handle.net/10150/611417.
Full textAbstract:
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California<br>This paper describes some of the signal conditioning and processing circuits that were developed to reconstruct the doppler video signal from a radar receiver under test. The reconstructed doppler video signal is then digitized and put into a telemetry frame for transmission to a ground receiving station.
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Aue, Volker. "Optimum linear single user detection in direct-sequence spread-spectrum multiple access systems." Thesis, Virginia Tech, 1995. http://hdl.handle.net/10919/43609.
Full textAbstract:
<p>After Qualcomm's proposal of the IS-95 standard, <i>code-division multiple access</i>
(CDMA) gained popularity as an alternative multiple-access scheme in cellular and <i>personal
communication systems</i> (PCS). Besides the advantage of allowing asynchronous
operation of the users, CDMA <i>direct-sequence spread spectrum</i> (DS-SS) offers resistance
to frequency selective fading and graceful degradation of the performance as the number
of users increases.</p>
<p>
Orthogonality of the signals in time-division multiple access and frequency-division
multiple access is inherent from the nature of the multiple access scheme. In a CDMA
system, orthogonality of the signals is not guaranteed in general. Consequently, the
performance of conventional correlation receivers suffers.</p>
<p>
Sub-optimum receivers which use knowledge of the interfering signals have been
investigated by other researchers. These receivers attempt to cancel the multi-user interference
by despreading the interfering users. Hence, these receivers require knowledge
about all the spreading codes, amplitude levels, and signal timing, and are, in general,
computationally intensive.</p>
<p>
In this thesis, a technique is presented for which a high degree of interference rejection
can be obtained without the necessity of despreading each user. It is shown
that exploiting spectral correlation can help mitigate the effects of the multiple-access
interference. If <i>code-on-pulse</i> DS-SS modulation is used, a cyclic form of the Wiener
filter provides substantial improvements in performance in terms of bit error rate and
user capacity. Furthermore, it is shown, that a special error-criterion should be used to
adapt the weights of the filter.</p>
<p>
The computational complexity of the receiver is equivalent to that of conventional
equalizers.</p><br>Master of Science
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Grant, Eugene. "INTERCEPTOR TARGET MISSILE TELEMETRY." International Foundation for Telemetering, 1997. http://hdl.handle.net/10150/607598.
Full textAbstract:
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada<br>A target missile is a unique piece of test hardware. This test tool must be highly reliable,
low cost and simple and must perform any task that the developing interceptor missile
planners require. The target missile must have ample power and guidance resources to put
the target in a specified place in the sky at a desired time. The telemetry and measurement
system for the target missile must have the same requirements as its interceptor missile but
must be flexible enough to accept new requirements as they are applied to the target and
its interceptor. The United States Army has tasked Coleman Aerospace to design and build
this type of target missile. This paper describes and analyzes the telemetry and
instrumentation system that a Hera target missile carries. This system has been flying for
the past two years, has completed seven out of seven successful test flights and has
accomplished all test objectives to date.
The telemetry and instrumentation system is an integral part of the missile self-test system.
All preflight checks and flight simulations are made with the on-board three-link telemetry
system through a radio frequency (RF) link directly through the missile antenna system to a
ground station antenna. If an RF transmission path is not available due to test range
restrictions, a fiber-optic cable links the pulse code modulator (PCM) encoder to the
receiving ground stations which include the bitsync, decommutator and recorders. With
this capability, alternative testing is not limited by RF test range availability.
The ground stations include two mobile stations and a factory station for all testing
including preflight testing of the missile system prior to flight test launches. These three
ground stations are built in a single configuration with additional equipment in the mobile
units for use at remote locations. The design, fabrication, testing and utilization of these
ground stations are reviewed. The telemetry system is a modification of the classical PCM
system and will operate with its interceptor missile at least into the first decade from the
year 2000.
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Hochner, William "Bill." "B-2 Flight Test Implementation of an Ethernet Based Network System for Data Acquisition." International Foundation for Telemetering, 2015. http://hdl.handle.net/10150/596404.
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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<br>Northrop Grumman Corporation's B-2 Flight Test Instrumentation team is revamping its entire Data Acquisition System (DAS) to be an Ethernet based network (EBN) system that will provide simplified wiring, higher speeds, greater capacity, and control over the data. The old system became obsolete in terms of capability and maintainability. New on-board avionic systems also demand that the Flight Test Instrumentation group (INSTR) accommodate fiber and high speed Ethernet data. In addition, the footprint and location for INSTR systems and components will be moved to remote areas. INSTR engineering selected the Teletronics Technology Corporation's Ethernet networked Data Acquisition Units (DAUs), known as MnDAUs, as the core system. Prior to the first flight utilization of the new INSTR DAS will undergo extensive lab and field testing to assure flight test effectiveness and the accuracy of all necessary data products. The goal is to acquire and employ the best system available while avoiding costly lessons.
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Martins, Gabriel Soares 1983. "Construção de um turbidímetro de baixo custo para controle de qualidade de efluentes industriais." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263484.
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Orientador: Luiz Otávio Saraiva Ferreira<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica<br>Made available in DSpace on 2018-08-21T21:54:45Z (GMT). No. of bitstreams: 1
Martins_GabrielSoares_M.pdf: 6495887 bytes, checksum: 4a05e53032d23853568df2eca3d4ecf7 (MD5)
Previous issue date: 2012<br>Resumo: Medir a qualidade da água sempre foi importante para as agências governamentais, organizações científicas e a própria sociedade manterem o nível de contaminação da água em patamares que não afetem a sobrevivência de nenhum ser vivo. Rastrear de forma mais detalhada e precisa os efluentes industriais que retornam aos rios e lagos das cidades, através da instalação de diversos medidores ao longo das linhas de distribuição de água industriais, auxilia na manutenção da qualidade da água destas fontes naturais. Os medidores existentes atualmente, conhecidos por turbidímetros, são caros, o que impede o amplo monitoramento das linhas de água. O objetivo desta dissertação é a construção de um turbidímetro de baixo custo que seja capaz de auxiliar na avaliação dos efluentes industriais. O turbidímetro proposto é baseado no GLI Método 2 (Great Lake Instruments Method 2), que emprega duas técnicas de espectroscopia: a nefelometria e a turbidimetria. A contribuição dada por esta dissertação está na aplicação da técnica de modulação por amplitude de pulso com amostragem instantânea, muito utilizada em telecomunicações, com o intuito de mitigar qualquer deslocamento do sinal devido às fontes de luz do ambiente e outras interferências do circuito eletrônico. O equipamento consegue medir uma faixa de turbidez de 16 a 4000 NTU. Abaixo de 16 NTU não há precisão nas medidas devido à intensa presença de ruído no sinal nefelométrico. Apesar de não conseguir medir o nível de turbidez aceitável de água apropriada para consumo (5 NTU), considera-se a faixa de medição suficiente para se medir efluentes indústrias e monitorá-los para não que não poluam os rios e reservatórios das cidades<br>Abstract: Measuring water quality has always been important for government agencies; scientific organizations and society maintain the level of water contamination at levels that do not affect the survival of any living being. Track, with more details and accuracy, the industrial effluents that return to the rivers and the lakes of the cities through the installation of several meters along the water lines of industries, helps maintain water quality of the natural sources. The meters currently existing, known for turbidimeters, are expensive, which prevents the widespread monitoring of water lines. The objective of this dissertation is design a low cost turbidimeter that is able to assist in the assessment of industrial effluents. The turbidimeter proposed is based on the GLI Method 2 (Great Lake Instruments Method 2), which employs two spectroscopic techniques: nephelometry and turbidimetry. The contribution of this dissertation is in applying the technique of pulse amplitude modulation with instantaneous sampling, widely used in telecommunications, in order to mitigate any signal offset due to ambient light sources and interference from the electronic circuit. The equipment can measure a range of 16-4000 turbidity NTU. Below 16 NTU there is no accuracy in measurements because the noise interfering in the nephelometric signal. Although the equipment cannot measure the acceptable turbidity level of drinking water (5 NTU), it is considered sufficient to measure industrial effluents and track them to not pollute the rivers and reservoirs of cities<br>Mestrado<br>Mecanica dos Sólidos e Projeto Mecanico<br>Mestre em Engenharia Mecânica
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Spáčil, Tomáš. "Bicí automat pro hudebníky." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220353.
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The aim of this work is to create a functional prototype of a drum machine with sound generating using a microcontroller. Introduction is devoted to general drum machine and an analysis of its parts, principle and basic modes of operation. The following chapter deals with the principle of digital signal processing and sound generation using a microcontroller. Part of this chapter is focused on mixing using compression methods. The core of this work is to design my own block structure and overall scheme of the drum machine with a description of the parts. Followed by analysis and implementation with theoretical and practical point of view. It is mainly about presentation and description of important parts of firmware codes, DPS design and another technical documentation useful for final prototype production. The conclusion contains a summary of the results with prezentation and discussion.
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Contino, Sergio. "Development of Software Tools for the Test of Ultra Wide Band Receivers." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/4327/.
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In the last years, the importance of locating people and objects and communicating with them in real time has become a common occurrence in every day life.
Nowadays, the state of the art of location systems for indoor environments has not a dominant technology as instead occurs in location systems for outdoor environments, where GPS is the dominant technology.
In fact, each location technology for indoor environments presents a set of features that do not allow their use in the overall application scenarios, but due its characteristics, it can well coexist with other similar technologies, without being dominant and more adopted than the others indoor location systems.
In this context, the European project SELECT studies the opportunity of collecting all these different features in an innovative system which can be used in a large number of application scenarios.
The goal of this project is to realize a wireless system, where a network of fixed readers able to query one or more tags attached to objects to be located.
The SELECT consortium is composed of European institutions and companies, including Datalogic S.p.A. and CNIT, which deal with software and firmware development of the baseband receiving section of the readers, whose function is to acquire and process the information received from generic
tagged objects.
Since the SELECT project has an highly innovative content, one of the key stages of the system design is represented by the debug phase.
This work aims to study and develop tools and techniques that allow to perform the debug phase of the firmware of the baseband receiving section of the readers.
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Cronje, Bernhard. "Evaluation of a poisson windowed test signal for pcm codecs." Thesis, 2015. http://hdl.handle.net/10539/16550.
Full textAbstract:
This project deals with the critical evaluation of a Poisson
windowed test signal which was proposed for in-service and
production testing of filtered pulse code modulation systems. The
Poisson windowed test signal has various advantages over the
existing two test methods specified by the International
Consultive Committee for Telephone and Telegraph (CCITT). The
main goals of the new test signal are to minimise the test time
and to accommodate the send- and reel eve filters normally found in
communication systems.
The evaluation process included the compilation of performance
curves of signal ,to noise ratio vs. signal level and gain
variation vs. signal level. These curves were compiled by
simulating the codec and filters on a digital computer and
processing the output data. Three sets of programs were
The results obtained revealed some fundamental limitations of the
proposed test signal. Using the basic properties of the Poisson
windowed signal, an alternative test signal was proposed. It was
the single sided exponentially windowed sinusoidal which proved
to be suitable for the testing of filtered pulse code modulation
stems.
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Wan-ZhenHuang and 黃婉甄. "Adaptive Differential Pulse Code Modulation for Audio Signals." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/qt67qr.
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Chen, Horng-Bin, and 陳鴻斌. "Advanced Double Predictor Differential Pulse Code Modulation Image Transmission System." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/52648235553857997819.
Full textAbstract:
碩士<br>大葉大學<br>電機工程研究所<br>87<br>The thesis is focused on the improvement of Double Predictor Differential Pulse Code Modulation algorithm for image data compression to increase the image transmission speed. We adopt the Quadtree segmentation algorithm to divide the real-world images into regions having widely differing perceptual importance. The detail regions of a given image will be segmented into blocks with smaller block size, and the background regions of the image will be assigned larger block size for the blocks. After the pre-processing of Quadtree segmentation, the differential values between the near by pixels of each image block are reduced. Therefore, we can decrease the distribution range of prediction error as well as reduce the bit rate and quantization levels.
We also use the double predictor DPCM architecture for the proposed image coding system. The conventional DPCM image coding system can be easily affected by a larger fed-back quanti-zation error while transmitted over an error-free channel. The advantage of double predictor DPCM system is to reduce the affect from the fed-back quantization error and not to increase the system complexity. The system performance results of the proposed variable block-size Double Predictor DPCM image encoder/decoder system are about 5 to 6 dB coding gain in signal to noise ratio（SNR） than the conventional DPCM system.
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Wu, tsong-nan, and 吳聰男. "The Research,Design and Application of Adaptive Pulse Code Modulation Speech Codec." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/81556512688010405338.
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碩士<br>淡江大學<br>電機工程學系<br>84<br>The speech application are very popular in the world today,
such as telephone,voice mail box,speech recognition,speech
synthesis...etc.The amout of orginal speech data is very large.
If we don't process those stored speech data , it must cost much
memory.For example,if we record speech signal with 8 KHZ
sampling rate and 8 bits per sample,we need 64k bits memory
per second and 3.84 Mbits per minute . In the region of speech
coding, people try to reduce the bit rate of speech data and
make reconstructed signal comfortable for people.This paper
focuses on using less bit rate to implement speech application.
Sound baster is used to record speech signal and Adaptive
Differential Pulse Code Modulation (ADPCM ) bases on
International Telegraph and Telephone Consultative Committee
(CCITT) G.721 standard is adopted to compress speech data in
this paper.The sampling rate is 8 KHZ and 4 bits per sample. In
ADPCM system , one word memory adaptive quantizer and adaptive
preditor is adopted to reduce bit rate in this paper. In the
decoder of ADPCM , a 8-bit mircocontroller is adopted to
implement this algorithm.Besides,the paper use verilog to
simulate the interface between the mircocontroller,memory and D-
to-A converter.After finishing all simulation,the paper uses
FPGA to verify whole system in real world. Besides,this paper
design a simple application using this speech decoder to make
sure the quantity of output speech accepted by the people.
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Wu, Cong-Nan, and 吳聰男. "The Research,Design and Application of Adaptive Pulse Code Modulation Speech Codec." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/56932765701443924098.
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CHUNG, HSIN-CHUN, and 鍾新志. "Advanced Double Predictor Dofferential Pulse Code Modulation Image Transmission System Over Fading Channel." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/15871976111878200226.
Full textAbstract:
碩士<br>大葉大學<br>電機工程研究所<br>90<br>ABSTRACT
In this study, we use quadtree segmentation method to improve the non-stationary statistic characteristics of digital image models. The double predictor differential pulse code modulation (DP-DPCM) system can reduce the quantization error than that in tradition differential pulse code modulation (DPCM) system. Therefore, DP-DPCM algorithm can possess better data compression ratio as well as increase system transmission rate. The transmission medium is modeled as a fading communication channel and quadrature phase shift keying (QPSK) modulation is adopted in the study. For channel coding, we use convolution encoder and maximum-likelihood Viterbi hard decision decoder. The channel coding scheme is to protect the transmitted source data and to reduce bit error rate (BER) in fading channel. Performance of this advanced double predictor differential pulse code modulation image transmission system over fading channel is evaluated in this research.
Key Words : quadtree segmentation, non-stationary statistical, double predictor differential pulse code modulation, differential pulse code modulation, quadrature phase shift keying, fading channel.