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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.
51

Micro NPU for Baseband Interconnect

Karlsson, Sara January 2014 (has links)
The aim of this work is to investigate the possibility to implement a configurable NPU (Network Processing Unit) in the next generation of Ericsson’s EMCAs (Ericsson Multi Core Architecture). The NPU is constructed so that it can be configured for either Ethernet or xIO-s, as either a transmitter or a receiver. The motive for doing the work is that many protocols have similar functions and there could be possible advantages to have a configurable protocol choice in future hardware. A model of a NPU will be created in SystemC using the TLM 2.0 interface. The model will be analyzed to evaluate its complexity regarding a possible modification to also make it configurable for CPRI. The result that is presented is that it would be possible to implement a configurable NPU in the future EMCAs. The result is based on the conclusion that the protocols use many similar functions and most of the blocks could be made configurable for use with different protocols. Configurable blocks would benefit a configurable NPU as it would require fewer resources than separate blocks for each protocol.
52

Ethernetbaserad fältbusskommunikation inom processindustrin

Strid, Mikael January 2017 (has links)
Inom processindustrin får fältbussar en allt viktigare funktion. Moderna distribuerade styrsystem kopplas ihop med avancerade ändnoder såsom smarta ställverk och frekvensomriktare, som i många fall har egna inbyggda styrsystem. Detta ställer höga krav på säker och tillförlitlig datakommunikation inom en processindustri. Idag används till största del två sorters fältbussteknologier: Seriell kommunikation via RS-485 samt paketbaserad kommunikation baserad på IEEE 802.3, även mer känt som Ethernet. Seriella fältbussar dominerar marknaden än idag trots att det är en föråldrad teknologi jämfört med Ethernet. Anledningarna till detta är flera: Då seriella fältbussar har varit i drift inom processindustrin i över 25 år så är det beprövat och kompetensen att underhålla och felsöka systemet finns ofta ute på industrierna. Driftsäkerhet prioriteras högt och tröskeln att gå över till ett nytt system är hög. En annan anledning är att processerna som styrs generellt sett är långsamma, oftast räcker cykeltider på 1s, samt att datamängden som överförs är relativt liten, så den långsammare transmissionshastigheten i en seriell fältbuss har inte utgjort någon begränsning. Ethernetbaserade fältbussar besitter dock intressanta fördelar över seriella men har även begränsningar som måste beaktas. I början på denna uppsatsundersöks en processindustris generella krav på en fältbuss. Därefter studeras för- och nackdelar med ethernetbaserade fältbussar samt det undersöktes om ett av de protokoll som används för fältbusskommunikation över ethernet, Profinet IO, levt upp till de krav som ställts. En fördel som framkommit med ethernetbaserade fältbussar är att det går att upprätta väldigt robusta nätverk med de protokoll som finns att tillgå. En nackdel är svårbestämd fördröjningstid på grund av best effortprincipen i paketförmedlade nätverk. Profinet IO löser detta genom synkron dataöverföring direkt ut på länklagret.Avslutningsvis så genomfördes ett praktiskt upprättande av en ethernetbaserad fältbuss där ett styrsystem kommunicerar med en frekvensomriktare över ett redundant ringnätverk. / Fieldbuses plays an increasingly more important function in the process industry. Modern distributed control systems coupled with advanced end nodes such as "smart" substations and frequency converters which in many cases have their own internal control systems. This places high demands on secure and reliable data communication within a process industry. Today mainly two types of fieldbus technologies are used: Serial communication via RS-485 and packet based communication based on IEEE 802.3, also known as Ethernet. Serial field buses dominate the market today, even though it is an obsolete technology compared to Ethernet. There are several reasons for this: Serial field buses have been in operation in the process industries for over 25 years, it a proven technology and the skills to maintain and troubleshoot the system are often found out on the floor. Process industries prioritize reliability and the threshold to move to a new system is high. Another reason is that the processes that are controlled are generally slow, usually a cycle time of 1s is sufficient, and that the amount of data transferred is relatively small so the slower transmission rate in a serial field bus has not been a limitation. Ethernet-based field buses, however, possess interesting advantages over serial buses but also has limitations that must be considered. At the beginning of this paper the process industry's general requirements on a fieldbus is examined. Then the pros and cons of Ethernet-basedfield buses are studied. After that it was investigated if one of the protocols used for fieldbus communication over Ethernet, Profinet IO, lived up to the requirements. One advantage that emerged with Ethernet-based field buses is that very robust networks can be established with the protocols that are available. A disadvantage is that it’s difficult to determine the delay due to the best effort principlein packet switched networks. Profinet IO solves this by synchronous data transfer directly out the link layer. Lastly there’s a practical implementation of an Ethernet-based fieldbus, where a control system communicates with a frequency converter over a redundant ring network.
53

Estudo para uma rede metropolitana comunitária

Lopes, Gil Coutinho Costa Seixas January 2006 (has links)
Tese de mestrado. Redes e Serviços de Comunicação. 2006. Faculdade de Engenharia. Universidade do Porto
54

Enabling gigabit IP for embedded systems /

Tsakiris, Nicholas, January 2009 (has links)
Thesis (M. Engin.)--Flinders University, School of Computer Science, Engineering and Mathematics. / Typescript bound. Includes bibliographical references (leaves 128-133). Also available online.
55

A Duel Compression Ethernet Camera Solution for Airborne Applications

Willis, Stephen, Langer, Bernd 10 1900 (has links)
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 / Camera technology is now ubiquitous with smartphones, laptops, automotive and industrial applications frequently utilizing high resolution imagine sensors. Increasingly there is a demand for high-definition cameras in the aerospace market - however, such cameras must have several considerations that do not apply to average consumer use including high reliability and being ruggedized for harsh environments. A significant issue is managing the large volumes of data that one or more HD cameras produce. One method of addressing this issue is to use compression algorithms that reduce video bandwidth. This can be achieved with dedicated compression units or modules within data acquisition systems. For flight test applications it is important that data from cameras is available for telemetry and coherently synchronized while also being available for storage. Ideally the data in the telemetry steam should be highly compressed to preserve downlink bandwidth while the recorded data is lightly compressed to provide maximum quality for onboard/ post flight analysis. This paper discusses the requirements for airborne applications and presents an innovative solution using Ethernet cameras with integrated compression that outputs two steams of data. This removes the need for dedicated video and compression units while offering all the features of such including switching camera sources and optimized video streams.
56

PTPV1 and PTPV2 Translation in FTI Systems

Lefevre, D., Cranley, N., Holmeide, Ø. 10 1900 (has links)
ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / A Flight Test Instrumentation (FTI) system may consist of equipment that either supports PTPv1 (IEEE 1588 Std 2002) or PTPv2 (IEEE 1588 Std 2008). The challenge in such time distributed system is the poor compatibility between the two PTP protocol versions. This paper describes how to combine the PTP versions in the same network with minimum or no manual configuration.
57

A Low Cost, High Density Reconfigurable Recording Subsystem

Berchuk, Vitaliy, Grozalis, Ed, Yin, Jennifer, Dehmelt, Chris 10 1900 (has links)
ITC/USA 2012 Conference Proceedings / The Forty-Eighth Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2012 / Town and Country Resort & Convention Center, San Diego, California / Modern test programs require an increase in sensor and bus data while at the same time seeking a decrease in the size and price of data acquisition components. Data archiving, which has been traditionally supplied via dedicated standalone hardware, is not exempt to this demand, but in many ways has not kept up with other instrumentation components in terms of flexibility, size, density and price. The archiving capabilities of a data acquisition system must be able to meet the changing needs of the customer. This paper presents a Solid State Drive (SSD) based data recorder implementation that can be easily reconfigured to address the requirements of different applications, including traditional PCM based systems and contemporary network based systems. The paper identifies the requirements, design challenges, trade-offs and risks in creating a low-cost, flexible data archiving subsystem that can be used in a standalone configuration or be directly integrated with a host data acquisition system.
58

Timing and Synchronization over Ethernet

Lundqvist, Emil January 2015 (has links)
In this thesis an investigation will be done on how time and frequency can be synchronized over Ethernet with help of Precision Time Protocol and Synchronous Ethernet. The goal is to achieve a high accuracy in the synchronization when a topology of 10 cascaded nodes is used. Different approaches may be used when implementing Precision Time Protocol for synchronization. They will be investigated and the best approach for a good accuracy will be proposed. Another question that this thesis will cover is how to recover a radio frequency, a multiple of 3.84 MHz from Ethernets 10.3125 GHz. By using hardware support for the timestamps and transparent clocks in the forwarding nodes the best accuracy is achieved for the time and phase synchronization. Combining this with Synchronous Ethernet for frequency synchronization, to get a traceable clock through the system, will lead to the best result. The total error does not need to be greater than 1.46~ns if the asymmetry in the medium is neglected and a welldesigned PCS and FIFO are used. Recovering the radio frequency from Ethernet is done by using the highest common frequency, either an integer phase locked loop or a fractional phase locked loop can be used. The fractional phase locked loop will give a better result but will contribute with spurs that the integer phase locked loop does not.
59

Reliable file transfer across a 10 megabit ethernet /

Van Dellon, Mark. January 1984 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1984. / Typescript. Includes bibliographical references (p. 71).
60

Carrier grade ethernet

Σπυροπούλου, Θεώνη Κατερίνα 15 October 2012 (has links)
Περιγραφή δομής, λειτουργίας, χαρακτηριστικών και υπηρεσιών του Carrier Grade Ethernet και των πρωτοκόλλων που υποστηρίζει. Μελέτη της τεχνολογίας σε πραγματικό δίκτυο, ανάπτυξη προγραμματιστικών εφαρμογών για αυτοματοποιημένη διαχείρηση κυκλωμάτων. / -

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