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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.
11

A Bidirectional Two-Hop Relay Network Using GNU Radio and USRP

Le, Johnny 08 1900 (has links)
A bidirectional two-hop relay network with decode-and-forward strategy is implemented using GNU Radio (software) and several USRPs (hardware) on Ubuntu (operating system). The relay communication system is comprised of three nodes; Base Station A, Base Station B, and Relay Station (the intermediate node). During the first time slot, Base Station A and Base Station B will each transmit data, e.g., a JPEG file, to Relay Station using DBPSK modulation and FDMA. For the final time slot, Relay Station will perform a bitwise XOR of the data, and transmit the XORed data to Base Station A and Base Station B, where the received data is decoded by performing another XOR operation with the original data.
12

Studying Media Access andControl Protocols

Mohammed, Alalelddin Fuad Yousif January 2010 (has links)
This thesis project’s goal is to enable undergraduate students to gain insight into media access and control protocols based upon carrying out laboratory experiments. The educational goal is to de-mystifying radio and other link and physical layer communication technologies as the students can follow packets from the higher layers down through the physical layer and back up again. The thesis fills the gap between the existing documentation for the Universal Software Radio Peripheral (USRP) resources and the knowledge of undergraduate students. This was necessary because the existing document is targeted at advanced audiences rather than undergraduates. This thesis describes the design and evolution of a workbench for students to experiment with a variety of media access and control protocols, much as Wireshark gives students the ability to watch network and higher layer protocols. Another motivation for this thesis is that an increasing number of communication networks use complex media access and control protocols and existing tools do not allow students to see the details of what is taking place in these protocols, except via simulation. Today an software defined radio and computer are affordable as laboratory equipment for an undergraduate course. Hence the time is ripe for the development of undergraduate laboratory course material using these tools. The thesis is targeted at (1) instructors of undergraduates who might use this work to develop their own lesson plans and course material and (2) students of physical and link layer protocols who want a practical tool for carrying out experiments in these layers. Hopefully by de-mystifying these lower layers and by making the USRP more approachable by undergraduate students we will encourage lots of students to view wireless network technology as being just as approachable as a wired Ethernet. Due to the widespread use of wireless communications technologies, there is a great need by industry for more graduates who can understand communication systems from the physical to the application layer - rather than the current situation where there is a hard boundary between the lower two layers and the upper layers. While there has been a lot of research concerning cross layer optimization, much of this is theoretical and not very approachable by students. A desired outcome of this thesis project is that undergraduate students will be able to understand tradeoffs at all layers of the protocol stack and not be limited to the upper layers. / Detta examensarbete har som mål att göra det möjligt för studenter att få inblick i tillgång till medierna och protokoll som grundar sig på att utföra laboratorieexperiment. Det pedagogiska målet är att de-mystifierande radio och annan länk och fysiska lagret kommunikationsteknik som studenterna kan följa paket från högre skikt ner genom det fysiska lagret och upp igen. Avhandlingen fyller gapet mellan den befintliga dokumentationen för Universal Software Radio Peripheral (usrp) resurser och kunskap om studerande. Detta var nödvändigt eftersom det befintliga dokument riktar sig till avancerade publik snarare än studenter. Denna avhandling beskriver utformningen och utvecklingen av en arbetsbänk för studenter att experimentera med olika tillgång till medierna och protokoll kontroll, mycket som Wireshark ger studenterna möjlighet att titta på nätet och högre skikt protokoll. Ett annat motiv för denna tes är att ett ökande antal kommunikationsnät använda komplicerade tillgång till medierna och protokoll kontroll och befintliga verktyg inte tillåter eleverna att se detaljer om vad som sker i dessa protokoll, utom via simulering. Idag en programvarustyrd radio och dator är överkomliga laboratorieutrustning för en grundutbildningskurs. Därför är tiden mogen för utvecklingen av grundutbildningen laborationer material med hjälp av dessa verktyg. Avhandlingen riktar sig till (1) instruktörer för studenter som kan använda detta arbete för att utveckla sin egen lektionsplanering och kursmaterial och (2) studenter på fysisk och länka protokoll skikt som vill ha ett praktiskt verktyg för att utföra experiment i dessa lager. Förhoppningsvis genom de-mystifierande de undre lagren och genom att göra usrp mer tillgänglig genom att studenter ska vi uppmuntra många elever att visa trådlös nätverksteknik vara lika lättillgänglig som ett ethernet. På grund av den utbredda användningen av trådlös kommunikationsteknik, finns ett stort behov från näringslivet för fler studenter som kan förstå kommunikationssystem från det fysiska till applikationslagret - i stället för den nuvarande situationen där det finns en hård gräns mellan de två lägre skikten och de övre skikten. Samtidigt som det har varit en hel del forskning om cross lager optimering, mycket av detta är teoretisk och inte särskilt tillgänglig av studenter. Ett önskat resultat med detta examensarbete är att studenter ska kunna förstå kompromisser på alla nivåer inom den protokollstack och inte vara begränsade till de övre skikten.
13

Multihop Transmission Opportunistic Protocol on Software Radio

Hirve, Sachin C. 08 October 2009 (has links)
No description available.
14

A GNU Radio Based Software-Defined Radar

Patton, Lee K. 12 June 2007 (has links)
No description available.
15

Enhancing GNU Radio for Run-Time Assembly of FPGA-Based Accelerators

Stroop, Richard Henry Lee 17 September 2012 (has links)
Software defined radios (SDRs) have changed the paradigm of slowly designing custom radios, instead allowing designers to quickly iterate designs with a large range of functionality. With the help of environments like the open-source project, GNU Radio, a designer can prototype radios with greatly improved productivity. Unfortunately, due to software performance limitations, there is no way to achieve the range of radio designs made possible with actual physical radio hardware. In order for SDRs to become more prevalent in radio prototyping and development, accelerators must be added to high-throughput and computationally intensive portions. Custom DSPs, GPUs, and FPGAs have all been added to SDRs to try and expand their computational capabilities. One difficulty in this is that by adding these accelerators, the "instant gratification" dynamic of the GNU Radio is lost. In this thesis, an enhanced GNU Radio flow is presented that seamlessly augments the GNU Radio software-only model with FPGAs, yet preserves the GNU Radio dynamics by providing full-custom radio hardware/software structures in seconds. By delegating portions of a GNU Radio flow graph to networked FPGAs, a larger class of software-defined radios can be implemented. Assembly of the signal processing structures within the FPGAs is accomplished using an enhanced flow where modules are customized, placed, and routed in a fraction of the time required by the vendor tools. With rapid FPGA assembly, a GNU Radio designer retains the ability to perform "what-if" experiments, which in turn greatly enhances productivity. Due to the modular nature of GNU Radio and of the FPGA designs, a modular assembly of the FPGA hardware is used. In the flow presented here, optimized hardware library components are designed by a domain expert, and stored as compact placed-and-routed modules. When a designer requests the assembly of one or more components within a given FPGA via a GNU Radio Python script, the necessary library components are accessed and translated to an appropriate location within the chip. Then the ports of the modules are stitched together using a custom FPGA router. This process reduces the large compile times of hardware for an FPGA to reasonable software-like times. To the radio designer, the complexity of the underlying hardware is abstracted away, making it appear as if everything compiles and runs in software, allowing many iterations to be realized quickly. Radio design can continue at the speeds that GNU Radio designers are accustomed to but with the range of possible waveforms and general functionality extended. / Master of Science
16

Enhancing GNU Radio for Hardware Accelerated Radio Design

Irick, Charles Robert 06 July 2010 (has links)
As technology evolves and new methods for designing radios arise, it becomes necessary to continue the search for fast and flexible development environments. Some of these new technologies include software defined radio (SDR), Field Programmable Gate Arrays (FPGAs), and the open source project GNU Radio. Software defined radio is a concept that GNU Radio has harnessed to allow developers to quickly create flexible radio designs. In terms of hardware, the maturity of FPGAs give radio designers new opportunities to develop high-speed radios having high-throughput and low-latency, yet the conventional build-time for FPGAs is a limiting factor for productivity. Recent research has lead to reductions in build-time by using FPGAs in a non-traditional manner, meaning productivity no longer has to be sacrificed. The AgileHW project demonstrated this concept and will be used as a basis to develop an overlaying architecture that uses a combination of the technologies mentioned to create a flexible, open, and efficient environment for radio development. This thesis discusses the realization of this architecture with the use of Xilinx FPGAs as a hardware accelerator for an enhanced GNU Radio. / Master of Science
17

PicoRF: A PC-based SDR Platform using a High Performance PCIe Plug-in Card Extension

Said, Karim A. 29 October 2012 (has links)
Wireless communication serves as the foundation for a wide range of services that have become an integral part of human life in this day and age. Driven by the desire to have a single piece of hardware that can provide multiple wireless services, attention has been directed to SDRs due to their programmable nature and the flexibility they can offer in operating over multiple standards. In addition, they can provide effective solutions to current challenges in wireless communication, such as spectrum overcrowding and inter-standard operability, as well as future challenges to come due to their upgradeability. Although SDRs have been around in the research community for over a decade, they have not reached the point of transitioning to the mass consumer market, size being one of the major obstacles. Numerous SDR hardware platforms have been developed demonstrating successful functionality, yet to this day most of them remain trapped in desktop/benchtop form factors which are not suited for mobility. A main factor contributing to the size of SDR units is the RF front end. Using current technology, wide-band operation of SDR RF front-ends is achieved by aggregating multiple dedicated components, each covering a portion of the frequency range. Recent technology advances have enabled the integration of wide frequency functionality inside a single integrated package. One example is a prototype RFIC transceiver chip from Motorola Research Labs which contains a complete direct conversion RF transceiver in a single chip, with a frequency coverage range of 100MHz-2.4GHz. RFIC5, the latest version of the chip, has additionally integrated high speed ADC and DAC units, leading to a significant reduction in the component count and the overall size of the SDR hardware. This thesis describes the implementation of a highly compact, SDR PC plug-in card, known as PicoRF. PicoRF is based on the Motorola's RFIC chip for the RF front-end functionality, while the combined computational power of a V5 FPGA and a PC host is used for waveform signal processing. An overlay gird consisting of an interconnection of PR slots is reserved on the FPGA to host the components of a signal processing pipeline which can be modified during run-time. Through a high speed PCIe connection, partial bitstreams can be downloaded from the host PC to the FPGA at a very high speed making it possible for the radio to modify its function in very short time intervals and greatly reducing the service interruption time. Control software running on the PC host manages the overall system operation including the RFIC which is controlled through a custom developed API. The combination of the laptop host and the plug-in card form a small form factor, mobile SDR node that is one step towards satisfying both the performance and ergonomics demand of the consumer market. / Master of Science
18

Radiolänk med GNU Radio

Nordin Hellström, Kristopher, Williams, Kenny January 2008 (has links)
<p>At the Department of Technology and Built environment at the University of Gävle there was an interest to study GNU Radio, which is an "open source radio project. The project is based on that most of the radio signal processing is made in an ordinary PC. The idea behind this degree project was that in a laptop there are several radio transmitters/receivers that takes space, generates heat and transmit in varied frequency band etcetera.</p><p> </p><p>All these radio transmitters/receivers could be replaced with a Software Defined Radio system. It means that one common, general radio hardware is used to different communications such as: WLAN, Bluetooth, GPRS, 3G etcetera. The waveform is generated in the software, which makes the system very flexible. To transmit and receive radio signals a USB-based hardware is required, for example from Ettus Research LLC.</p><p> </p><p>During this degree project two PC:s was used for the signal processing and the signal transferring. The operating system that was used on the computers, were the Linux based Ubuntu 8.04. To generate the signals, to modulate/demodulate the signals and to get the communication on the sound cards in/out-port working, the different packages in the GNU Radio software was used and for programming the high level language, Python, was used.</p><p> </p><p>In this degree project a lot of experiments where made, for example a sine wave was generated in computer 1 and the signal was amplitude modulated and transferred to computer 2, through the sound card. In computer 2 the signal was demodulated and filtrated, before it was saved to the hard drive. When the signal was saved on computer 2, it could be sent out on the sound card and be studied on an oscilloscope. This transfer between the computers was made with a stereo cable, but also with a radio link equipment on the University of Gävle.</p><p> </p><p>The result of this degree project was satisfying, because the signal was possible to modulate, transfer, demodulate and save. In the wire transfer a lot of noise was generated on to the signal, mostly because of the sound cards. When the wireless transfer was made it appeared more noise, because of the quality of the receiver, the transmitter and the antennas.</p><p> </p><p>This work can be developed to more advanced systems.</p> / <p>Vid Högskolan i Gävle på institutionen för Teknik och Byggd miljö (ITB) fanns ett intresse att undersöka GNU Radio, som är ett open source radio-projekt. Projektet bygger på att den största delen av radiosignalbehandlingen sker i en vanlig PC. Idén som låg till grund för detta examensarbete var att det i en laptop finns ett stort antal radiosändar- och mottagarkretsar som tar plats, genererar värme och sänder på olika frekvensband med mera.</p><p> </p><p>Alla dessa radiosändar- och mottagarkretsar skulle kunna ersättas med ett Software Defined Radio-system. Vilket innebär att en gemensam, generell radiohårdvara används för olika kommunikationer som: WLAN, Bluetooth, GPRS, 3G med flera. Vågformerna genereras i mjukvaran, vilket gör systemet mycket flexibelt. För att kunna ta emot och sända radiosignaler behövs en hårdvara. Denna hårdvara har bland annat Ettus Research LLC tagit fram, med USB-anslutning.</p><p> </p><p>Under examensarbetet har två stycken PC använts för behandling av signaler, samt överföring mellan dessa. Operativsystemet som användes på datorerna var det Linuxbaserade Ubuntu 8.04. För att generera signaler, modulation/demodulation av dessa signaler samt för att få kommunikation med ljudkortets in-/utgång att fungera, användes de olika paketen i mjukvaran GNU Radio och för programmering användes högnivåspråket Python.</p><p> </p><p>I detta examensarbete utfördes ett flertal experiment, bland annat genererades en sinussignal i dator 1 och signalen amplitudmodulerades och överfördes till dator 2 via ljudkortet. På dator 2 demodulerades denna signal och filtrerades, innan den sparades på hårddisken. Signalen kunde sedan skickas ut på ljudkortet och studeras med ett oscilloskop. Överföringen mellan datorerna gjordes med en stereokabel, men också med en radiolänkutrustning som fanns på Högskolan i Gävle.</p><p> </p><p>Resultatet var tillfredställande då signalen kunde moduleras, överföras samt demoduleras och sparas. I den trådbundna överföringen uppstod mycket brus i signalen, till största delen berodde detta på ljudkorten. När den trådlösa överföringen gjordes uppstod mera brus, vilket berodde på kvalitén hos mottagare, sändare och antennerna.</p><p> </p><p>Detta arbete kan utvecklas till mer avancerade system.</p>
19

Radiolänk med GNU Radio

Nordin Hellström, Kristopher, Williams, Kenny January 2008 (has links)
At the Department of Technology and Built environment at the University of Gävle there was an interest to study GNU Radio, which is an "open source radio project. The project is based on that most of the radio signal processing is made in an ordinary PC. The idea behind this degree project was that in a laptop there are several radio transmitters/receivers that takes space, generates heat and transmit in varied frequency band etcetera.   All these radio transmitters/receivers could be replaced with a Software Defined Radio system. It means that one common, general radio hardware is used to different communications such as: WLAN, Bluetooth, GPRS, 3G etcetera. The waveform is generated in the software, which makes the system very flexible. To transmit and receive radio signals a USB-based hardware is required, for example from Ettus Research LLC.   During this degree project two PC:s was used for the signal processing and the signal transferring. The operating system that was used on the computers, were the Linux based Ubuntu 8.04. To generate the signals, to modulate/demodulate the signals and to get the communication on the sound cards in/out-port working, the different packages in the GNU Radio software was used and for programming the high level language, Python, was used.   In this degree project a lot of experiments where made, for example a sine wave was generated in computer 1 and the signal was amplitude modulated and transferred to computer 2, through the sound card. In computer 2 the signal was demodulated and filtrated, before it was saved to the hard drive. When the signal was saved on computer 2, it could be sent out on the sound card and be studied on an oscilloscope. This transfer between the computers was made with a stereo cable, but also with a radio link equipment on the University of Gävle.   The result of this degree project was satisfying, because the signal was possible to modulate, transfer, demodulate and save. In the wire transfer a lot of noise was generated on to the signal, mostly because of the sound cards. When the wireless transfer was made it appeared more noise, because of the quality of the receiver, the transmitter and the antennas.   This work can be developed to more advanced systems. / Vid Högskolan i Gävle på institutionen för Teknik och Byggd miljö (ITB) fanns ett intresse att undersöka GNU Radio, som är ett open source radio-projekt. Projektet bygger på att den största delen av radiosignalbehandlingen sker i en vanlig PC. Idén som låg till grund för detta examensarbete var att det i en laptop finns ett stort antal radiosändar- och mottagarkretsar som tar plats, genererar värme och sänder på olika frekvensband med mera.   Alla dessa radiosändar- och mottagarkretsar skulle kunna ersättas med ett Software Defined Radio-system. Vilket innebär att en gemensam, generell radiohårdvara används för olika kommunikationer som: WLAN, Bluetooth, GPRS, 3G med flera. Vågformerna genereras i mjukvaran, vilket gör systemet mycket flexibelt. För att kunna ta emot och sända radiosignaler behövs en hårdvara. Denna hårdvara har bland annat Ettus Research LLC tagit fram, med USB-anslutning.   Under examensarbetet har två stycken PC använts för behandling av signaler, samt överföring mellan dessa. Operativsystemet som användes på datorerna var det Linuxbaserade Ubuntu 8.04. För att generera signaler, modulation/demodulation av dessa signaler samt för att få kommunikation med ljudkortets in-/utgång att fungera, användes de olika paketen i mjukvaran GNU Radio och för programmering användes högnivåspråket Python.   I detta examensarbete utfördes ett flertal experiment, bland annat genererades en sinussignal i dator 1 och signalen amplitudmodulerades och överfördes till dator 2 via ljudkortet. På dator 2 demodulerades denna signal och filtrerades, innan den sparades på hårddisken. Signalen kunde sedan skickas ut på ljudkortet och studeras med ett oscilloskop. Överföringen mellan datorerna gjordes med en stereokabel, men också med en radiolänkutrustning som fanns på Högskolan i Gävle.   Resultatet var tillfredställande då signalen kunde moduleras, överföras samt demoduleras och sparas. I den trådbundna överföringen uppstod mycket brus i signalen, till största delen berodde detta på ljudkorten. När den trådlösa överföringen gjordes uppstod mera brus, vilket berodde på kvalitén hos mottagare, sändare och antennerna.   Detta arbete kan utvecklas till mer avancerade system.
20

[en] IMPLEMENTATION OF THE ENERGY DETECTOR AND PERFORMANCE ANALYSIS SCHEMES IN GNU RADIO: SIMULATIONS AND TESTS / [pt] IMPLEMENTAÇÃO DO DETECTOR DE ENERGIA E ESQUEMAS DE ANÁLISE DE DESEMPENHO NO GNU RADIO: SIMULAÇÕES E TESTES

ELIZEU CALEGARI 28 September 2018 (has links)
[pt] O rádio cognitivo é uma tecnologia que visa o compartilhamento do espectro radioelétrico entre usuários primários licenciados e os demais usuários secundários de maneira harmoniosa, sem provocar interferências que prejudiquem a prestação dos serviços e visando uma melhoria na eficiência do uso do espectro radioelétrico, que é um recurso cada vez mais escasso. No âmbito da pesquisa referente a esta dissertação, é construído e implementado no GNU Radio um esquema de avaliação de desempenho de detectores para rádio cognitivo, é construído o detector de energia, e são implementadas simulações computacionais e ensaios por meio de duas USRP para avaliar o desempenho do detector criado, visando os requisitos do padrão IEEE 802.22. / [en] Cognitive radio is a technology that aims to share the radio spectrum between licensed primary users and other secondary users in a harmonious way without causing interference that prevent the services provision and aiming at an improvement in the efficiency in the use of the radioelectric spectrum, which is a resource increasingly scarce. In the scope of the research related to this dissertation, a performance evaluation scheme of cognitive radio detectors is constructed and implemented in GNU Radio, the energy detector is constructed, and computational simulations and tests are implemented through two USRPs to evaluate the performance of the detector created, targeting the requirements of the IEEE 802.22 standard.

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