Radio technology is rapidly evolving and as processing capabilities and algorithms become more complex, the need for alternative compilation and user interface abstraction increases. Field Programmable Gate Array (FPGA) technology introduces unique reconfigurable hardware architectures that can aid in software defined radio (SDR) design. FPGAs have greater processing capability than traditional general purpose processors (GPP) found in desktop workstations. This work builds on an ongoing project, GReasy, that augments a Linux based open source SDR development platform, GNU Radio, with FPGA processing capabilities. By delegating processing intensive portions of a radio design to the Xilinx Zynq FPGA architecture, the domain of deployable radios by GNU Radio can be broadened. Xilinx Zynq, integrates the FPGA fabric and CPU onto a single chip, which eliminates the need for a controlling host computer; thus, providing a single, portable, low-power, embedded platform. This thesis presents a Zynq capable version of GNU Radio -- an open-source rapid radio deployment tool -- with an enhanced flow that utilizes the processing capability of FPGAs. This work features TFlow -- an FPGA back-end compilation accelerator for instant FPGA assembly. GReasy generates a description of the hardware components that are used by TFlow for the instant FPGA assembly. Once the FPGA is programmed with a design based on the description generated by GReasy, modules and the target hardware can be parameterized to realize an even larger class of applications and further solidify the concept of rapid assembly of software defined radios. / Master of Science

Cognitive radio technology has been an important area of research in telecommunications for solving the problem of spectrum scarcity. That\'s because in addition to allowing dynamic allocation of the electromagnetic spectrum, cognitive radios must be able to identify the non cognitive user\'s transmission on the channel. This operation is only possible through the continuous sensing of the electromagnetic spectrum. In this context, this paper presents a detailed study on spectrum sensing, an important stage in cognitive radio technology. For the presentation of this work, a detailed study on software dened radio (SDR) was carried out, without which it would be impossible to work with cognitive radios, once they are implemented by means of SDR technology. It was also presented the tools GNU Radio and USRP, which together form a solution of SDR, through implementation of AM receivers. The theoretical foundations of spectrum sensing and blind source separation (BSS) are presented and then is made a detailed study of the use of BSS for spectral sensing. From the study of BSS, it is possible to use new metrics for decision making about the presence or the absence of a primary user in the channel. Throughout the study, simulations and implementations were conducted on MATLAB in order to perform various situations, and, nally, it is presented outcomes and conclusions reached during the work. / A tecnologia de rádio cognitivo tem sido uma importante área de pesquisa em telecomunicações para a solução do problema da escassez espectral. Isto porque, além de permitirem a alocação dinâmica do espectro eletromagnético, os rádios cognitivos devem ser capazes de identificar as transmissões de usuários não cognitivos no canal. Esta operação só é possível por meio do sensoriamento contínuo do espectro eletromagnético. Neste contexto, este trabalho apresenta um estudo detalhado sobre o sensoriamento de espectro, uma importante etapa da tecnologia de rádios cognitivos. Para a apresentação deste trabalho foi realizado um estudo detalhado a respeito de rádio definido por software (SDR), sem o qual não seria possível o trabalho com rádios cognitivos, uma vez que este é implementado por meio da tecnologia de SDR. Também foram apresentadas as ferramentas GNU Radio e USRP, que, juntas, formam uma solução de SDR, por meio de implementações de receptores AM. Os fundamentos teóricos de sensoriamento de espectro e separação cega de fontes (BSS) são apresentados e, em seguida, é realizado um estudo aprofundado do uso de BSS para o sensoriamento espectral. A partir do estudo de BSS, é possível utilizar novas métricas de decisão a respeito da presença ou não de um usuário primário no canal. Durante todo este trabalho foram realizadas implementações e simulações no MATLAB com a finalidade de executar diversas situações e, finalmente, são apresentados resultados verificados e conclusões obtidas neste trabalho. / Mestre em Ciências

Massive deployment of diverse ultra-low power wireless devices necessitates the rapid development of communication protocols. Software Defined Radio (SDR) provides a flexible platform for deploying and evaluating real-world performance of these protocols. But SDR platform based communication systems suffer from high and unpredictable delays. There is a lack of comprehensive understanding of the characteristics of the delays experienced by these systems for new SDR platforms like LimeSDR. This knowledge gap needs to be filled in order to reduce these delays and better design protocols which can take advantage of these platforms. We design a GNU Radio based IEEE 802.15.4 experimental setup, where the data path is time-stamped at various points of interest to get a comprehensive understanding of the characteristics of the delays. Our analysis shows GNU Radio processing and LimeSDR buffering delay are the major delays in these data paths. We try to decrease the LimeSDR buffering delay by decreasing the USB transfer size but it comes at the cost of increased processing overhead. The USB transfer packet size is modified to investigate which USB transfer size provides the best balance between buffering delay and the processing overhead across two different host computers. Our experiments show that for the best-measured configuration the mean and jitter of latency decreases by 37% and 40% respectively for the host computer with higher processing resources. We also show that the throughput is not affected by these modifications. Higher processing resources help in handling higher processing overhead and can better reduce the buffering delay. / Stora installationer av heterogena extremt energisnåla trådlösa enheter ställer krav på snabb utveckling av kommunikationsprotokoll. Mjukvarubaserad radio (Software Defined Radio, SDR) tillhandahåller en flexibel plattform för att installera och utvärdera faktisk prestanda för dessa protokoll. Men SDR-baserade system har problem med stora och oförutsägbara fördröjningar. Verklig förståelse av hur dessa fördröjningar beter sig i nya plattform som LimeSDR saknas. Dessa kunskapsbrister behöver överbryggas för att kunna minska fördröjningarna och för att mer framgångsrikt kunna designa protokoll som drar nytta av de nya plattformarna. Vi skapar en försöksuppställning för IEEE 802.15.4 baserad på GNU Radio. Data som passerar systemet tidsstämplas för att ge underlag till att förstå fördröjningarnas egenskaper. Vår analys visar att fördröjningarna främst kommer från processande i GNU-radion och buffertider för LimeSDR. Vi försöker minska buffertiderna för LimeSDR genom att minska paketstorleken för USB-överföring, men det kommer till priset av ökade bearbetningskostnader. Paketstorleken för USB-överföring modifieras för att på två olika testdatorer undersöka den bästa balansen mellan buffertider och bearbetningskostnader. Våra experiment visar att för att den mest noggrant undersökta försöksuppställningen så minskar medelvärdet och jittret för fördröjningarna med 37% och 40% för testdatorn med mest beräkningskraft. Vi visar också att genomströmningen inte påverkas av dessa ändringar. Med mer beräkningskraft kan de ökade bearbetningskostnader hanteras, och buffertiderna kan förkortas mer effektivt.

With the development of powerful computational resources such as Digital Signal Processors and Field Programmable Gate Arrays, It has become possible to utilize many radio functions via software. This is the main concept of an up-and-coming technology of Software Defined Radio. In the Thesis, a number of platforms for implementation of Software Defined Radio has been evaluated. Platform that proved to be most suitable for the project was Ettus’ USRP N210. Using the platform, implementation of 802.15.4 Zigbee’s physical layer was done, where experiments whose outputs can later be used to compare performance with respect to "hardware radios" were performed. / Med utvecklingen av enheter med kraftfulla beräkningsegenskaper som “Digital Signal Processors” och “Field Programmable Gate Arrays” har det blivit möjligt att implementera flera radiofunktioner i mjukvara. Det är huvudkonceptet i den uppåtgående teknologin mjukvaru definierad radio.I det här examensarbetet har ett flertal plattformar för mjukvaru definierad radioutvärderats. Plattformen som visade sig vara mest lämplig för projektet var Ettus USRP N210. En implementation av IEEE 802.15.4 Zigbees fysiska lager har realiserats till plattformen. Experiment, vars utdata senare kan användas för att jämföra prestanda mellan mjukvaru definierad radio och hårdvaru baserad radio, har även utförts. / TESLA - Time-critical and Safe wireLess Automation communication / GAUSS - Guaranteed Automation communication Under Severe disturbanceS

Radio Frequency IDentification (RFID) is a contactless, automatic identification wireless technology primarily used for identifying and tracking of objects, goods and humans. RFID is not only limited to identification and tracking applications. This proliferating wireless technology has been deployed in numerous securities sensitive applications e.g. access control, e-passports, contactless payments, driver license, transport ticking and health cards. RFID inherits all the security and privacy problems that are related to wireless technology and in addition to those that are specific to RFID systems. The security and privacy protection schemes proposed in literature for wireless devices are mostly secured through symmetric/asymmetric keys encryption/decryption and hash functions. The security of all these cryptographic algorithms depends on computationally complex problems that are hard to compute using available resources. However, these algorithms require cryptographic operations on RFID tags which contradict the low cost demand of RFID tags. Due to limited number of logic gates in tags, i.e., 5K-10K, these methods are not practical. Much research effort has done in attempt to solve consumer's privacy and security problem. Solutions that prevent clandestine inventory are mostly application layer techniques. To solve this problem, a new RFID physical layer scheme has been proposed namely Direct Sequence Backscatter Encryption (DSB Enc). The proposed scheme uses level generator to produce different levels before transmitting the signal to the tag. The tag response to the signal sent by the reader using backscatter communications on the same signal which looks random to the eavesdropper. Therefore eavesdropper cannot extract the information from reader to tag and tag to reader communication using passive eavesdropping. As reader knows the different generated levels added to the carrier signal, it can remove the levels and retrieve the tag's messages. We proposed a lightweight, low-cost and practically secure physical layer security to the RFID system, for a supply chain processing application, without increasing the computational power and tag's cost. The proposed scheme was validated by simulations on GNU Radio and experimentation using SDR and a WISP tag. Our implementation and experimental results validate that DSB Enc is secure against passive eavesdropping, replay and relay attacks. It provides better results in the presence of AWGN channel.

In this thesis, we present the design and implementation of a CubeSat receiver system using the Universal Software Radio Peripheral (USRP) and GNU Radio. The goal of this project is to develop a low-cost and flexible ground station capable of receiving telemetry and payload data from CubeSats in real time. The CubeSat receiver operates in the UHF frequency range with a center frequency of 435 MHz and uses a software-defined radio (SDR) approach to provide wideband signal processing and demodulation capabilities. The satellite transceiver transmits an Ax.25 Transciever packet every 1 second using the Pumpkin CubeSat kit programmed in MPLab. To achieve this goal, we discuss the design considerations for the receiver system, including the selection of suitable hardware components and the development of custom software blocks in GNU Radio. We also developed the GFSK-based transmitter and receiver in GNU Radio, as well as a tracking system for the satellite. To decode the Ax.25 radio packet transmitted by the Pumpkin CubeSat kit, we developed an Ax.25 deframer in GNU Radio to decode the received signal. Our results demonstrate that the CubeSat receiver is capable of receiving and demodulating AX.25 formatted radio signals from Transciever. Additionally, we show that the receiver system is scalable and can be easily adapted for use with other CubeSat missions. Overall, our work provides a practical solution for CubeSat communication and lays the groundwork for future developments in low-cost CubeSat ground station technology.

The goal of software-defined radio (SDR) is to move the processing of radio signals from the analog domain to the digital domain — to use digital microchips instead of analog circuit components. Until faster, higher-precision analog-to-digital (ADCs) and digital-to-analog converters (DACs) become affordable, however, some analog signal processing will be necessary. We still need to convert high-radio frequency (RF) signals that we receive to low intermediate-frequency (IF) or baseband (centered on zero Hz) signals in order for ADCs to sample them and feed them into microchips for processing. The reverse is true when we transmit. Amplification is also needed on the receive side to fully utilize the dynamic range of the ADC and power amplification is needed on the transmit side to increase the power output from the DAC for transmission. Analog filtering is also needed to avoid saturating the ADC or to filter out interference when receiving and to avoid transmitting spurs. The analog frequency conversion, amplification and filtering section of a radio is called the RF front end. This thesis describes work on a new RF front end daughterboard for the Universal Software Radio Peripheral, or USRP. The USRP is a software-radio hardware platform designed to be used with the GNU Radio software radio software package. Using the Motorola RFIC4 chip, the new daughterboard receives RF signals, converts them to baseband and does analog filtering and amplification before feeding the signal into the USRP for processing. The chip also takes transmit signals from the USRP, converts them from baseband to RF and amplifies and filters them. The board was designed and laid out by Randall Nealy. I wrote the software driver for GNU Radio. The driver defines the interface between the USRP and the RFIC chip, controls the physical settings, and calculates and sets the hundreds of variables necessary to operate this extremely complex chip correctly. It allows plug-and-play compatibility with the current USRP daughterboards and supplies additional functions not available in any other daughterboard. / Master of Science

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.

In wireless communication systems, one of the most important resources being focused on all the researchers is spectrum. A cognitive radio (CR) system is one of the efficient ways to access the radio spectrum opportunistically, and efficiently use the available underutilized licensed spectrum. Spectrum utilization can be significantly enhanced by developing more applications with adopting CR technology. CR systems are implemented using a radio technology called software-defined radios (SDR). SDR provides a flexible and cost-effective solution to fulfil the requirements of end users. We can see a lot of innovations in Internet of Things (IoT) and increasing number of smart devices. Hence, a CR system application involving an IoT device is studied in this thesis. Opportunistic spectrum access involves two tasks of CR system: spectrum sensing and dynamic spectrum access. The functioning of the CR system is rest upon the spectrum sensing. There are different spectrum sensing techniques used to detect the spectrum holes and a few of them are discussed here in this thesis. The simplest and easiest to implement energy detection spectrum sensing technique is used here to implement the CR system. Dynamic spectrum access involves different models and strategies to access the spectrum. Amongst the available models, an interweave model is more challenging and is used in this thesis. Interweave model needs effective spectrum sensing before accessing the spectrum opportunistically. The system designed and simulated in this thesis is capable of transmitting an output from an IoT device using USRP and GNU radio through accessing the radio spectrum opportunistically.

Denna studie genomför en detaljerad undersökning av två olika plattformar för programvarudefinierad radio (SDR), GNU Radio och Simulink, för att avgöra vilken som är mest lämpad för integration i en specifik kurs inom läroplanen vid mittuniversitet. Utvärderingen fokuserar på nyckelprestandamått såsom beräkningskapacitet, simuleringens hastighet och visualiseringsförmåga, vilket ger en omfattande jämförelse mellan dessa två plattformar. Undersökningen inleds med att simulera det fysiska lagret av WiFi, vilket är ett grundläggande krav för kursens laboratoriearbete. Studiens omfattning utvidgas sedan för att inkludera simuleringar av andra nätverkstekniker som 4G. Denna expansion syftar till att samla in omfattande data för en mer noggrann jämförelse och för att grundligt utvärdera varje plattforms förmåga att hantera olika nätverkssimuleringar. Dessutom fördjupar studien sig i olika simuleringstekniker genom att diskutera två distinkta angreppssätt till SDR-simuleringar, vilket belyser deras respektive styrkor och tillämpbarhet i ett utbildningssammanhang. Det slutgiltiga målet med denna forskning är att avgöra om GNU Radio erbjuder betydande fördelar jämfört med MATLABs Simulink och om det bör ersätta Simulink som det primära verktyget som används i denna kurs. I förväntan på potentiella förändringar har nya alternativa laborationsinstruktioner för GNU Radio också utvecklats och presenterats. Dessa instruktioner är utformade för att underlätta en smidig övergång om universitetet beslutar att anta GNU Radio, för att säkerställa att utbildningsmålen fortsätter att uppnås på ett effektivt och effektivt sätt. Även om studien visar att GNU Radio erbjuder bättre beräkningskapacitet var själva simuleringsprocessen något svårare. De två plattformarna uppnådde nästan samma resultat, men GNU Radio krävde extra arbete. Med tanke på att inlärningsresultaten var liknande men inlärningsprocessen med GNU Radio var mer komplicerad bedömdes GNU Radio som olämplig för denna kurs. / This study conducts a detailed examination of two distinct Software Defined Radio (SDR) platforms, GNU Radio and Simulink, to ascertain which is more suited for integration into a specific course within the curriculum at Mid University. The evaluation focuses on key performance metrics such as computing efficiency, simulation speed, and visualization capabilities, providing a comprehensive comparison between these two platforms. The investigation begins by simulating the physical layer of WiFi, which is a fundamental requirement of the course laboratory work. The scope of the study is then broadened to include simulations of other network technologies like 4G. This expansion aims to collect extensive data for a more accurate comparison and to thoroughly evaluate the capabilities of each platform in handling various network simulations. Moreover, the study delves into different simulation methodologies by discussing two distinct approaches to SDR simulations, highlighting their respective strengths and applicabilities in an educational context. The ultimate objective of this study is to determine whether GNU Radio offers a significant advantage over MATLAB’s Simulink and if it should replace Simulink as the primary tool used in this course. In anticipation of potential changes, new alternative laboratory instructions for GNU Radio are also developed and presented. These instructions are designed to facilitate a smooth transition should the university decide to adopt GNU Radio, ensuring that educational goals continue to be met efficiently and effectively. While the study shows that GNU Radio offers better computing efficiency, the process of simulating was somewhat more challenging. The two platforms accomplished almost the same tasks, but GNU Radio required extra effort. Considering that the learning outcomes were similar but the learning process with GNU Radio was more difficult, GNU Radio was deemed unsuitable for this course.