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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.
1

Detection and Classification of Interference in Mobile Communication Systems / Detektion och klassificering av störningar i mobila kommunikationssystem

Ring, Christoffer January 2015 (has links)
The usage of wireless technology has in the past decade vastly increased and it continues to do so as well. Because of this, we become more and more reliant on this considerably fragile technology. Wireless technology, which uses radio waves to transmit data from one point to another can easily be interfered by radio jammers. This thesis work is about the detection and classification of the interference that is produced by jammers over the Global System for Mobile Communications (GSM) air interface. A typical GSM jammer that can be found on the Internet is analyzed but also more advanced GSM jammers are analyzed. The GSM standard is analyzed to find vulnerabilities that a jammer can take advantage of. The result is an interference detector that can be used to detect and classify interference over the GSM networks. The detector is constructed with an Universal Software Radio Peripheral (USRP) but is also portable to other software-defined radio (SDR) platforms.
2

FMCW radar implemented with GNU Radio Companion

Zhu, Qizhao, Wang, Yaqi January 2016 (has links)
Continuous-wave frequency-modulated radar, or FMCW radar, is simple in design, small in size and weight and uses low transmitting power. The range resolution depends on the bandwidth. FMCWradar is used in applications ranging from guided weapons systems to vehicle collision avoidance systems. Measuring the distance to the target is the essential feature of FMCW radar. Firstly, this thesis introduces the basic structure of the FMCW radar and the principle formeasuring distance. Secondly, by using software-dened radio (SDR),FMCW radar can be implemented and congured with a reduced costand complexity. In this report, the radar is implemented by means ofthe software GNU Radio Companion with a test signal. HackRF may be used in future work with an osmocom source instead of the testsignal.
3

Waveform Development using Software Defined Radio

Sundquist, Thomas January 2006 (has links)
<p>Software Defined Radio (SDR) is a conception of implementing radio functions in computer software, instead of having electronics performing the functions. This thesis aims to compare two different ways of implementing these functions, or waveforms.</p><p>The Software Communications Architecture (SCA) is an open standard developed by the United States Department of Defense. It uses a CORBA interface environment to make waveform applications interoperable and platform independent. This method of developing SDR is compared to an open-source initiative going by the name GNU Radio.</p><p>Two waveform applications are developed, one transmitter using SCA, and one receiver using GNU Radio. The analog radio interface is simulated using the sound cards of two regular PCs. The development is done using the C++ and Python programming languages.</p><p>This thesis examines pros and cons of the two SDR methods, as well as performing studies of Software Defined Radio in general.</p>
4

Chirp Sounding and HF Application : SDR Technology Implementation

Dautbegovic, Dino January 2012 (has links)
From a HF propagation point of view, the ionospheric layers act as partially conducting media (plasma) in which a transmitted radio wave can reflect upon.A way of determining whether a radio wave with a given frequency will reflect from the ionosphere or completely penetrate is to utilize special radar instruments know as ionosondes or chirp sounders. The technique is widely used by amateur enthusiasts and military radio users for monitoring available radio channel links between two remote locations and can often serve as a base for HF radio prognoses.The objective of this Bachelor’s Thesis was to explore, implement and test a single channel receiver for monitoring ionospheric sounders. The implementation is based on Software Defined Radio (SDR) technology and relies on the GNU Chirp Sounder (gcs) open source script program.
5

Waveform Development using Software Defined Radio

Sundquist, Thomas January 2006 (has links)
Software Defined Radio (SDR) is a conception of implementing radio functions in computer software, instead of having electronics performing the functions. This thesis aims to compare two different ways of implementing these functions, or waveforms. The Software Communications Architecture (SCA) is an open standard developed by the United States Department of Defense. It uses a CORBA interface environment to make waveform applications interoperable and platform independent. This method of developing SDR is compared to an open-source initiative going by the name GNU Radio. Two waveform applications are developed, one transmitter using SCA, and one receiver using GNU Radio. The analog radio interface is simulated using the sound cards of two regular PCs. The development is done using the C++ and Python programming languages. This thesis examines pros and cons of the two SDR methods, as well as performing studies of Software Defined Radio in general.
6

Wideband and Narrowband Spectrum Sensing Methods Using Software Defined Radios

Stegman, Jason Karl 01 August 2014 (has links)
The ability to accurately sense the surrounding wireless spectrum, without having any prior information about the type of signals present, is an important aspect for dynamic spectrum access and cognitive radio. Energy detection is one viable method, however its performance is limited at low SNR and must adhere to Nyquist sampling theorem. Compressive sensing has emerged as a potential method to recover wideband signals using sub-Nyquist sampling rates, under the presumption that the signals are sparse in a certain domain. In this study, the performance and some of the practical limitations of energy detection and compressive sensing are compared via simulation, and also implementation using the Universal Software Radio Peripheral (USRP) software defined radio (SDR) platform. The usefulness and simplicity of the USRP and GNU Radio software toolkit for simulation and experimentation, as well as some other application areas of compressive sensing and SDR, is also discussed.
7

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.
8

Multihop Transmission Opportunistic Protocol on Software Radio

Hirve, Sachin C. 08 October 2009 (has links)
No description available.
9

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
10

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

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