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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.
21

Wireless transceiver for the TLL5000 platform : an exercise in system design

Perkey, Jason Cecil 26 August 2010 (has links)
This paper will present the hardware system design, development, and plan for implementation of a wireless transceiver for The Learning Labs 5000 (TLL5000) educational platform. The project is a collaborative effort by Vanessa Canac, Atif Habib, and Jason Perkey to design and implement a complete wireless system including physical hardware, physical layer (PHY-layer) modulation and filters, error correction, drivers and user-interface software. While there are a number of features available on the TLL5000 for a wide variety of applications, there is currently no system in place for transmitting data wirelessly from one circuit board to another. The system proposed in this report is comprised of an external transceiver that communicates with a software application running on the TLL-SILC 6219 ARM9 processor that is interfaced with the TLL5000 baseboard. The details of a reference design, the hardware from the GNU Radio project, are discussed as a baseline and source of information. The state of the project and hardware design is presented as well as the specific portions of the project to which Jason Perkey made significant contributions. / text
22

Efficient wireless transmission supporting internet of things

Ghasemiahmadi, Mohammad 19 December 2017 (has links)
The promise of Internet of Things (IoT) and mass connectivity has brought many applications and along with them many new challenges to be solved. Recognizing sensor networks as one of the main applications of IoT, this dissertation focuses on solutions for IoT challenges in both single-hop and multi-hop communications. In single-hop communications, the new IEEE 802.11ah and its Group Synchronized Distribution Coordination Function (GS-DCF) is studied. GS-DCF categorized nodes in multiple groups to solve the channel contention issue of dense networks. An RSS-Based grouping strategy is proposed for the hidden terminal problem that can arise in infrastructure-based single hop communications. For multi-hop communications, Physical Layer Network Coding (PNC) is studied as a robust solution for multi-hop packet exchange in linear networks. Focusing on practical and implementation issues of PNC systems, different challenges have been addressed and a Software Defined Radio (SDR) PNC system based on USRP devices is proposed and implemented. Finally, extensive simulation and experimental results are presented to evaluate the performance of the proposed algorithms in comparison with currently used methods. / Graduate
23

Emulátor signálu navigačního systému GPS / Global Positioning System Signal Emulator

Hofman, Jan January 2012 (has links)
Thesis is adressed to the principals of a satellite navigation. It is focused on a determination of a longitude, latitude and altitude of a single point on the surface of the Earth. It contains analysis of navigation messages and a manner of processing of navigation signals in GPS receivers. Realization of an emulator of the navigation signal of GPS system in Matlab is also described. The purpose of this emulator is a generation of navigation messages, which could be transmitted by universal software radio. The last part of thesis contains the analysis of these signals, which were captured by second software radio.
24

Analýza GSM sítě pomocí open source SW rádia / Analysis of GSM network, using open source SW radio

Kilian, Petr January 2013 (has links)
This master thesis is focused on analysis and creation of GSM network, using open-source projects. For such creation is used software defined radio – in this thesis kit USRP1 which uses OpenBTS with GNURadio. As a switchboard is used PBX Asterisk and for testing GSM network was used OsmocomBB (on Motorola C123) and Airprobe (on Nokia 3310) projects. Installation and implementation are part of this thesis. In thesis have been also created two scripts for simplify of the work with projects and one laboratory task.
25

Využití moderních vícetónových modulací v bezdrátových sítích / Application of modern multitone modulations in wireless networks

Hamada, Adam January 2013 (has links)
The main aim of this master's thesis was the create function models of wireless network technologies using the modern multitones modulation like is PFDM and FMT. This work is realised in Matlab – Simulink enviroment and models are tested in development kit. Development kit is universal software defined radio developer by Ettus.
26

Parametry komunikačních systémů založených na OFDM-CDMA / Parameters of Communication Systems Based on OFDM-CDMA

Blumenstein, Jiří January 2013 (has links)
Cíl disertační práce leží v oblasti modelování a vyhodnocení bezdrátových komunikačních systémů s dvojrozměrným rozprostíráním signálu a jejich klíčových parametrů v závislosti na vybraných vlastnostech moderního bezdrátového komunikačního řetězce. Výzkumné metody použité v této práci spočívají především ve vývoji softwarového simulátoru pro prostředí Matlab, s jehož pomocí, a s využitím statistického přístupu, jsou navržené algoritmy ověřeny. Dále je použit simulátor fyzické vrstvy dle 3rd Generation Partnership Project Long Term Evolution (3GPP LTE), vyvinutý na Technické univerzitě ve Vídni. Tento představuje ideální platformu pro implementaci metody dvojrozměrného (2D) rozprostírání a její vyhodnocení s přihlédnutím k současným bezdrátovým komunikačním systémům. Zjištění prezentovaná v této práci představují především ověření účinnosti systému nazvaného jako Variable Spreading Factor - Orthogonal Code Frequency Division Multiplex (VSF-OFCDM), který využívá principu 2D rozprostírání signálu a zjištění, že VSF-OFCDM systém překonává systémy využívající Orthogonal Division Frequency Multiplex (OFDM), nebo Code Division Multiple Access (CDMA). Dále byla navržena metoda 2D rozprostírání signálu v systému LTE, kde se též potvrdila její účinnost. Díky účinnějšímu potlačení vlivu rychlé variace přenosového kanálu v závislosti na frekvenci a čase, dosahuje systém VSF-OFCDM znatelně vyšší datové prostupnosti.
27

Wireless Physical Layer Design for Confidentiality and Authentication

Wang, Tao 03 July 2019 (has links)
As various of wireless techniques have been proposed to achieve fast and efficient data communication, it’s becoming increasingly important to protect wireless communications from being undermined by adversaries. A secure and reliable wireless physical layer design is essential and critical to build a solid foundation for upper layer applications. This dissertation present two works that explore the physical layer features to secure wireless communications towards the data confidentiality and user authentication. The first work builds a reliable wireless communication system to enforce the location restricted service access control. In particular, the work proposes a novel technique named pinpoint waveforming to deliver the services to users at eligible locations only. The second work develops a secure far proximity identification approach that can determine whether a remote device is far away, thus preventing potential spoofing attacks in long-haul wireless communications. This dissertation lastly describes some future work efforts, designing a light-weight encryption scheme to facilitate sensitive data encryption for applications which cannot support expensive cryptography encryption operations such as IoT devices.
28

Configurable SDR Operation for Cognitive Radio Applications using GNU Radio and the Universal Software Radio Peripheral

Scaperoth, David Alan 13 September 2007 (has links)
With interoperability issues plaguing emergency responders throughout the country, Cognitive Radio (CR) offers a unique solution to streamline communication between police, Emergency Medical Technicians (EMT), and military officers. Using Software Defined Radio (SDR) technology, a flexible radio platform can be potentially configured using a Cognitive Engine (CE) to transmit and receive many different incompatible radio standards. In this thesis, an interface between a Cognitive Engine and an SDR platform is described which modifies (i.e., configures) the radio's operation. The interface is based upon communicating information via eXtensible Markup Language (XML) data files that contain the radio's Physical (PHY) parameters. The XML data files have been designed such that more development can be made to its structure as this research develops. The GNU Radio and the Universal Software Radio Peripheral (USRP) serve as the SDR platform for an example implementation. The example implementation involves importing XML data files into the SDR for quick configuration. Three configuration examples are used to describe this process. / Master of Science
29

Computational Complexity of Signal Processing Functions in Software Radio

Shah, Kushal Yogeshkumar 20 December 2010 (has links)
No description available.
30

Experimental Study of Cooperative Communication using Software Defined Radios

Marunganti, Murali Krishna January 2010 (has links)
No description available.

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