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Wireless communication analysis using software defined radio
Štrajt, Martin ; Štůsek, Martin (referee) ; Pokorný, Jiří (advisor)
The work deals with the use of software-defined radio as a probe for monitoring the operation of wireless communication according to the IEEE 802.11a/g standard. In the theoretical introduction, the concept of software-defined radio as a hardware device with software programmable circuits enabling the transmission or reception of signals in theoretically any frequency band is introduced. The introduction also contains adescription of selected devices and the IEEE 802.11 protocol with its most used additionsand modulations. In the first part of the practical part of the work, wireless communication is capturedusing a wireless network card in monitoring mode. The intercepted communication was decrypted and this decrypted traffic was compared with the data captured by the probe within the network. These results then served as acomparative basis for software-defined radio capturing. The focus of this work is to verify the capabilities of software-defined radio and its use for sniffing wireless communicationin the frequency band 2.4 GHz and 5 GHz. The attempt to use a software-defined radio here results from the scalability and adaptability that a wireless card cannot offer due to fixed hardware parameters. LimeSDR mini, LimeSDR and bladeRF 2.0 devices were used for capture. First, the configuration of the operating system, the installation of drivers and programs for control and work with selected devices are described. After verifying the functionality of the software-defined radio, a model of a signal decoder with the parameters of the IEEE 802.11g standard captured from the radio spectrum was put into operation. Finally, the data streams captured by the software-defined radio and the wireless network card were compared side by side. The results showed that the software-defined radio in the used configuration captures only a part of the total volume of transmitted frames.
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Signal Analyzer Based on DVB-T USB Tuner
Belica, Martin ; Grézl, František (referee) ; Černocký, Jan (advisor)
This bachelor thesis deals with the detection and analysis of a radio signals with the DVB-T USB tuner. The first step of the analysis is to capture some radio signal, in this case using a USB tuner. The next step is the appliction of signal processing algorithms. The most important algorithm for analysis is a discrete Fourier transform that is used to obtain a signal spectrum. Finally, several demodulation and filtering algorithms are used to better interpret the analyzed signal to the user.
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Multicarrier modulator and demodulator for software defined radio
Klučka, Jaroslav ; Urban, Josef (referee) ; Maršálek, Roman (advisor)
This thesis deals with computer simulation of the communication chain using the OFDM modulation. In the beginning of my thesis there is a brief description of digital modulations, especially OFDM. The model of the transmitter, radio channel and receiver, including a simple timing and frequency synchronization and equalization is designed and simulated in the Matlab environment. There is a designed communication system implemented into USRP development board in the Simulink environment. The development board could not work simultaneously as a transmitter and as a receiver. Function of the transmitter was verified by measuring on spectrum analyzer. Testing OFDM signal using the arbitrary waveform generator CompuGen 4302 was generated for the verification of the function of the receiver. Testing signal was received and demodulated on the development board which works as a receiver.
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Signal analyzer based on universal USB DVB-T receiver
Hoferek, Jakub ; Vychodil, Josef (referee) ; Derbek, Vojtěch (advisor)
This thesis deals with using a commercially available USB DVB-T tuner for spectrum analysis. In the first part, there are other possible platforms compared to income described hardware specific receiver tuner R820T and AD converter RTL2832. The next part is realized by a spectrum analyzer and a simple FM receiver. These functional units are created on GNU Radio and Matlab.
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Implementation of software radio into FPGA
Šrámek, Petr ; Maršálek, Roman (referee) ; Prokeš, Aleš (advisor)
The common objective of this project is implementation of software defined radio (SDR) into FPGA. The text contains review and comparison of several hardware concepts intended for SDRs implementation then the methods for digital implementation of various components of radios as the filters, mixers and others are mentioned. Part of the text introduces used hardware platform and describes software support for designing, simulations and implementation into hardware. Significant part of project describes complex of external hardware components as filter, amplifier and control panel designed and built within the project realization. But the main part of project demonstrates design of the software solution of radio receiver. There is specified architecture of radio for FM broadcast receiving, next the more complex systems with carrier recovery algorithm are presented. These systems are able to work with AM, BPSK and QPSK modulations. It is possible to implement all these receivers into hardware and verify their operation. The practical laboratory theme has been outlined within the project run.
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Security assessment of standards of IEEE 802.11 family
Řihánek, Tobiáš ; Pospíšil, Jan (referee) ; Pokorný, Jiří (advisor)
The aim of this work was to analyze the issue of security testing of the IEEE 802.11 protocols. The thesis includes a theoretical analysis of these protocols and a list of their vulnerabilities. Software used for testing the security was showcased. A utility was created to help with the testing. Finally, the thesis looks at the use of SDR as a way of testing security.
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Front end for software receiver
Slezák, Jakub ; Horský, Pavel (referee) ; Šrámek, Petr (advisor)
This thesis deals with a theoretical analysis of the basic parameters of receivers, input circuit architecture and signal digitization. According to the specified assignment it is outlined block scheme of front end for software receiver with specified components and the total bilance is calculated. Individual parts of the system are designed and realized. This is a set of four input filters for bandwidths: short waves up to 30 MHz, 87,5-108 MHz, 144-148 MHz and 174-230 MHz. The main point of design is a circuit containing a low-noise amplifiers, switches, and two amplifiers with adjustable amplification. Mainly are used integrated circuits from Analog Devices corporation. To control the various switches and adjustable amplifiers was designed a separate panel, which is connected to the main circuit via a cable. In the last phase was the whole system and its components subjected to measurements. Thanks to a number of mounted SMA connectors it is possible to measure different parts of the system and we are able to modify it partially.
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Design and implementation of a wireless transmission system using USRP
Vaclík, Michal ; Mlýnek, Petr (referee) ; Krajsa, Ondřej (advisor)
This thesis is focused on design and possibilities of implementation of modular wireless communications system based on software defined radio. This system uses USRP1 kits from Ettus Research and is controlled by GNU Radio Companion software. Final Python script is used to controll and modify parameters of modulation schemes, encoder properties and used bitrate. Thesis also describes possibilities and challenges of using radio HW for transmitting and receiving. Final chapter summerizes and analyzes achieved transmission qualities.
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SDR based Shortwave Receiver
Karetka, Gregor ; Maršálek, Roman (referee) ; Waldecker, Miroslav (advisor)
Práca sa zaoberá krátkovlnným prijímačom založeným na báze SDR (softvérovo definované rádio). Cieľom je navrhnúť a simulovať analógový predstupeň krátkovlnného prijímača pripojeného do Red Pitaya, ktorý dokáže prijímať vysielanie služby DRM. Návrh využíva mixovanie s duálnou konverziou. Návrh obsahuje systémovú schému a schému navrhovaného zariadenia a realizáciu DPS, ktoré bolo simulované na systémovej úrovni pro určenie dôležitých parametrov (zisk, prenos, citlivosť, SNR, atď.). Následne bola realizovaná doska plošného spoja, ktorá bola osadená, a na ktorej boli vykonané merania. S pomocou Red Pitaya bol implementovaný QPSK demodulátor v Matlabe.
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Satellite Telemetry Archive
Vorálek, Jan ; Povalač, Aleš (referee) ; Urbanec, Tomáš (advisor)
This thesis deals with a design of telemetry archive of PSAT, PSAT-2 and BRICSat sattelites. This telemetry data need to be extracted from SDR IQ records. The thesis contains a Doppler effect theory and description of structure of telemetry data. Then it presents a design of a program for Doppler effect correction, demodulation and decoding of these records and saving the data to telemetry archive. Thesis also deals with analysis of decoded data.
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