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Hosseininejad, BijanDesign and Implementation of a Versatile Wireless Communication System via Software Defined Radio
Master of Science in Engineering, Youngstown State University, 2009, Department of Electrical and Computer Engineering
The purpose of this work is to design and implement a low cost and flexible Software Defined Radio platform. Software Defined Radio is an emerging technology that gives engineers and scientists the ability to create reconfigurable wireless technology. Functions that were traditionally performed in hardware are implemented in software, thus making a Software Defined Radio reconfigurable without requiring hardware modifications. Current Software Defined Radio designs are usually based on a personal computer or Field Programmable Gate Array and offer either flexibility at a high cost of implementation or a low cost of implementation that sacrifices flexibility. In this work, a Software Defined Radio platform is presented which offers flexibility with a low cost of implementation. This is achieved by using a personal computer-based architecture with Universal Serial Bus interface to the analog-to-digital conversion and Radio Frequency modules. This external hardware interface, constructed from off the shelf components, provides the versatility for the proposed Software Defined Radio platform at minimal cost. A proof-of-concept design is then implemented and tested, which demonstrates the feasibility of the design.

Committee:

Faramarz Mossayebi, PhD (Advisor); Frank X. Li, PhD (Committee Member); Jalal Jalali, PhD (Committee Member)

Subjects:

Electrical Engineering

Keywords:

Software Defined Radio; SDR; wireless communication; software radio; reconfigurable radio; personal computer-based radio

Legg, J. RobertJob Satisfaction at University Licensed FM Public Radio Stations: An Application of Herzberg’s Motivation-Hygiene Theory
Doctor of Philosophy (PhD), Ohio University, 2004, Telecommunications (Communication)

Public radio represents a significant part of many universities. These same stations continue to be underrated resources, subject to little scholarly research. This study evaluates the levels of satisfaction and dissatisfaction among student and staff employees for eighteen job-related factors as originally identified by Frederick Herzberg. Data was gathered via questionnaires developed by Frank Friedlander in conjunction with Herzberg. Statistical analysis was performed on the data. Qualitative interviews were conducted with members of management having supervisory duties. The study reveals general adherence to the theory and identifies areas of importance to staff and students. The study also identifies factors among student workers that differ from the theoretical expectations. Contrary to previous corporate studies, students in this investigation rated the hygiene issues of interpersonal relationships as significant elements of job satisfaction. The study concludes with a discussion of station manager realization and manipulation of these motivation-hygiene factors among his or her employees and suggestions for those in upper-administration and law-making positions.

Committee:

Charles Clift (Advisor)

Subjects:

Mass Communications

Keywords:

Job Satisfaction; Motivation and Hygiene; Herzberg; Public Radio; University Radio; Radio Managment

Mian, OmerIntelligent Spectrum Sensor Radio
Master of Science in Engineering (MSEgr), Wright State University, 2008, Electrical Engineering
A cognitive radio is a radio with built-in intelligence that makes it able to utilize the radio frequency spectrum more efficiently by adapting to the changing conditions and frequency availability. In this thesis a spectrum sensor radio is designed that detects transmissions in FM band and determine the range of used and unused frequencies within the band. The radio then starts a transmission on a frequency among the available frequencies. This intelligent radio system design is implemented using the Universal Software Radio Peripheral and GNU Radio with a program written in python that uses a number of GNU Radio modules along with other python and C-Shell scripts giving a working baseline structure of a cognitive radio.

Committee:

Zhiqiang Wu, PhD (Advisor); Yong Pei, PhD (Committee Member); Xiaodong Zhang, PhD (Committee Member)

Subjects:

Electrical Engineering; Engineering

Keywords:

Cognitive Radio; Software-defined Radio; GNU; gnu radio

Mannar Mannan, PallaviFRAMEWORK FOR THE DESIGN AND IMPLEMENTATION OF SOFTWARE DEFINED RADIO BASED WIRELESS COMMUNICATION SYSTEM
Master of Science, University of Akron, 2005, Electrical Engineering
The aim of this thesis is to design and implement a software defined radio based wireless communication system. Software defined radio is a feasible solution for reconfigurable radios, which can perform different functions at different times on the same hardware. The baseband section of a wireless communication system is first simulated and then implemented in hardware. The performance of the baseband transmitter is analyzed using constellation and eye diagrams for different modulation techniques and different signal-to-noise ratios, while considering an additive white Guassian noise channel. The performance of the receiver is analyzed by comparing the input and output waveforms. The performance of the system in real time is also analyzed by implementing the system in hardware using Xilinx Spartan 2E field programmable gate array. A comparison of the simulation results with the results obtained from implementing the system on Spartan 2E hardware is presented and discussed. It is shown that the simulation results and experimental results are similar.

Committee:

Okechukwu Ugweje (Advisor)

Keywords:

de¿¿¿¿¿¿ned; RADIO; software de¿¿¿¿¿¿ned; software de¿¿¿¿¿¿ned radio; de¿¿¿¿¿¿ned radio; System Generator; SDR

Banjade, ArjunCommunity Radio in Nepal: A Case Study of Community Radio Madanpokhara
Doctor of Philosophy (PhD), Ohio University, 2007, Mass Communication - Telecommunications (Communication)

This study is about Community Radio Madanpokhara (CRM) in Palpa district in Western Nepal. Initiated and managed by the local residents, CRM has been on the air on frequency modulation (FM) band serving 800,000 potential listeners in the region since 2000. Triangulating in-depth interviews, observations and an audience survey as methods, this research explores the nature and extent of the local residents’ participation in the communication process.

The station, operating with a wide participation from its community members, has not only been successful in providing them with an access to much needed information and entertainment but has also, in fact, proved to be an important avenue for the local population to express their opinions and views as well as exchange feelings. An audience survey, conducted in January 2004, revealed that 80.8 percentage of the local respondents listen to their community radio station for information and entertainment.

Community radio in the region not only took away listeners from the state owned radio station, it also added new listeners. Thus, operation of a community radio station is not about sharing power, but it is also about creating new power. CRM has increased access to information for a larger section of rural population previously not served or underserved by the state media or the capital based-elite media. If knowledge is power and democracy is more about decentralization of power, then community radio stations in Nepal are truly championing this cause by creating many centers of power in the nation by empowering those left behind in the process and by securing their active involvement. They are encouraging the dispossessed and the marginalized in breaking the ages-old culture of silence, and CRM is leading the way in this endeavor.

Committee:

Drew McDaniel (Advisor)

Subjects:

Mass Communications

Keywords:

Community; Radio; Nepal; Madanpokhara; Media; Participatory Radio; Development Radio

Haus, David RussellEXPERTISE AT WAR: THE NATIONAL COMMITTEE ON EDUCATION BY RADIO, THE NATIONAL ASSOCIATION OF BROADCASTERS, THE FEDERAL RADIO COMMISSION AND THE BATTLE FOR AMERICAN RADIO
Doctor of Philosophy (Ph.D.), Bowling Green State University, 2006, History
In 1930 a group of educators formed the National Committee on Education by Radio (NCER) to fight for the preservation of non-profit education radio stations while also combating the meteoric rise of commercial radio programs. Between 1930 and 1934 the NCER would do battle with the commercial radio industry and its trade organization, the National Association of Broadcasters, attempting to carve out a safe space for educational, non-profit radio through a mixture of lobbying efforts and grass-roots activism. Ultimately the NCER lost its battle with the passage of the Communications Act of 1934. Other scholars have explored this moment in American history, arguing that the NCER stood little chance for success because of its own ineptitude and a powerful commercial industry. This dissertation attempts to understand its choices and motivations in the struggle for educational radio while examining the broader implications of the NCER’s arguments on our understanding of New Deal politics, associationalism, gender, and consumerism. The NCER waged a principled campaign to protect the home from commercialism and prevent Eastern cultural colonization of the United States by providing a redemptive space on the air. The NCER was an organization steeped in a fusion of humanitarian progressivism and populism that informed and limited its courses of action. It believed that it had valuable, relevant expertise to offer the federal government in deciding the model of American radio. I conclude that the NCER was not an inept organization that ultimately failed to achieve its goals. Instead it was a progressive group that watched the very progressive machinery its members once supported quash its campaign for radio reform and alter its conception of democracy, seeing federal regulators devalue its gendered expertise and watching educational radio sacrificed at the altar of the New Deal. However, the NCER posed a greater threat to the commercial industry than previously believed, and could have succeeded under different circumstances. The NCER fought against the conflation of consumerism and democracy while fighting to stave off cultural domination by the East coast, and it compels us to rethink the nature and periodization of progressivism.

Committee:

Leigh Ann Wheeler (Advisor)

Subjects:

History, United States

Keywords:

Radio; Radio History; Progressive Era; New Deal; National Committee on Education by Radio

Dutton, Kevin E.Theory and performance of an X-band radio frequency phase-differencing position tracking system
Doctor of Philosophy (PhD), Ohio University, 2003, Electrical Engineering & Computer Science (Engineering and Technology)

A radio frequency microwave X-band (10 GHz) indoor position tracking system is designed, constructed, and analyzed. The system consists of a transmitter of unknown location, free to move, and four fixed receiver antennas in known locations. The transmitter generates carrier signals on two frequencies. The transmitter is assumed to start at known location, to calibrate for the hardware phase offsets. High speed sampling is performed on the single stage down-converted signals, and estimates of the initial phase offset on each channel of sampled data are made. These estimates are differenced between antennas (single difference) and between frequencies (double difference). The double difference or wide lane measurements are used to provide a rough position solution, from which the narrow lane, or single frequency, carrier phase integer ambiguities are determined. The position solution is then refined with the use of the narrow lane integers and narrow lane measurements. The combination of large signal to noise ratio and a large number of samples results in single frequency phase estimates of very small oise variance. For the combination of frequencies tested, multipath was the dominant error source. The results indicate that if the narrow lane integers are found exactly in the hand-over from the wide lane solution, extremely precise millimeter level positioning is possible even in a multipath-rich environment.

Committee:

Frank van Graas (Advisor)

Keywords:

X-band radio; radio frequency; phase-differencing position; position tracking system

Patton, Lee K.A GNU Radio Based Software-Defined Radar
Master of Science in Engineering (MSEgr), Wright State University, 2007, Electrical Engineering
GNU Radio is an open source software-defined radio project, and the Universal Software Radio Peripheral (USRP) is hardware designed specifically for use with GNU Radio. Together, these two technologies have been used to implement very sophisticated, yet low cost, software-defined radios. Since software-defined radio and software-defined radar are really one in the same technologies, it stands to reason that GNU Radio and the USRP could be utilized to form a low cost radar sensor. In this thesis, we discuss the design of a prototype software-defined radar, built using the open source GNU Radio and open specification USRP projects. The prototype design is introduced, followed by the results of laboratory testing. A discussion on the expected operational performance of the prototype is then provided. The thesis concludes with the development and analysis of a waveform optimization algorithm that is capable of improving signal to interference plus noise ratio in the presence of a band-limited interferer. The low computational complexity of this algorithm make it amenable to software-defined radar.

Committee:

Brian Rigling (Advisor)

Keywords:

GNU Radio; Software-Defined Radio; Software-Defined Radar

Stickler, David CollierSome properties of the electromagnetic field in a stratified layer /
Doctor of Philosophy, The Ohio State University, 1964, Graduate School

Committee:

Not Provided (Other)

Subjects:

Engineering

Keywords:

Radio waves;Radio meteorology

Ghosh, ChittabrataInnovative Approaches to Spectrum Selection, Sensing, and Sharing in Cognitive Radio Networks
PhD, University of Cincinnati, 2009, Engineering : Computer Science and Engineering
In a cognitive radio network (CRN), bands of a spectrum are shared by licensed (primary) and unlicensed (secondary) users in that preferential order. It is generally recognized that the spectral occupancy by primary users exhibit dynamical spatial and temporal properties. In the open literature, there exist no accurate time-varying model representing the spectrum occupancy that the wireless researchers could employ for evaluating new algorithms and techniques designed for dynamic spectrum access (DSA). We use statistical characteristics from actual radio frequency measurements, obtain first- and second-order parameters, and define a statistical spectrum occupancy model based on a combination of several different probability density functions (PDFs). One of the fundamental issues in analyzing spectrum occupancy is to characterize it in terms of probabilities and study probabilistic distributions over the spectrum. To reduce computational complexity of the exact distribution of total number of free bands, we resort to efficient approximation techniques. Furthermore, we characterize free bands into five different types based on the occupancy of its adjacent bands. The probability distribution of total number of each type of bands is therefore determined. Two corresponding algorithms are effectively developed to compute the distributions, and our extensive simulation results show the effectiveness of the proposed analytical model. Design of an efficient spectrum sensing scheme is a challenging task, especially when false alarms and misdetections are present. The status of the band is to be monitored over a number of consecutive time periods, with each time period being of a specific time interval. The status of the sub-band at any time point is either free or busy. We proved that the status of the band over time evolves randomly, following a Markov chain. The cognitive radio assesses the band, whether or not it is free, and the assessment is prone to errors. The errors are modeled probabilistically and the entire edifice is brought under a hidden Markov chain model in predicting the true status of the band. After spectrum sensing, our research direction is on spectrum sharing using cooperative communication. We discuss allocation strategies of unused bands among the cognitive users. We introduce a cooperative N-person Game among the N cognitive users in a CRN and then identify strategies that help achieve Nash equilibrium. When licensed users arrive in any of those sub-bands involved in unlicensed user communication, the affected cognitive users in those bands remove them out of the N-person game and assess their optional strategies with the licensed users using the 2-person game approach for coexistence with the licensed users. In the sequel of spectrum sharing, we present three novel priority-based spectrum allocation techniques for enabling dynamic spectrum access (DSA) networks employing non-contiguous orthogonal frequency division multiplexing (NC-OFDM) transmission. The allocation of bandwidth to unlicensed users, without significantly increasing the interference on the existing licensed users, is a challenge for Ultra Wideband (UWB) networks. We propose a novel Rake Optimization and Power Aware Scheduling (ROPAS) architecture for UWB networks as multipath diversity in UWB communication encourages us to use a Rake receiver.

Committee:

Dharma Agrawal (Advisor); Raj Bhatnagar (Committee Member); Chia-Yung Han (Committee Member); Yiming Hu (Committee Member); Marepalli Rao (Committee Member)

Subjects:

Computer Science

Keywords:

Cognitive Radio; Software Defined Radio; Spectrum Sensing; Spectrum Sharing; Game Theory; Hidden Markov Models

Cutno, PatrickAutomatic Modulation Classifier - A Blind Feature-Based Tool
Master of Science, Miami University, 2016, Computational Science and Engineering
Automatic modulation classifiers (AMC) are one of the basic building blocks of electronic warfare receivers and cognitive radios. Although many research papers on AMC algorithms have been published, very few results on their implementation are available. This thesis presents a feature-based AMC built upon a software-defined radio platform. The developed AMC can detect signals over a broad spectrum and classify the modulation used. The modulation schemes considered in this thesis are amplitude modulation (AM), frequency modulation (FM), phase-shift keying (PSK), and quadrature amplitude modulation (QAM). Experimental results demonstrate the validity of the developed AMC algorithm and its implementation.

Committee:

Chi-Hao Cheng, Ph.D (Advisor); Dmitriy Garmatyuk, Ph.D (Committee Member); Jason Pennington, Ph.D (Committee Member)

Subjects:

Communication; Computer Engineering; Computer Science; Electrical Engineering; Engineering; Experiments; Technology

Keywords:

Software Defined Radio; NI USRP-2920; USRP; Modulation; Automatic Modulation Detection; Automatic Modulation Classification; AMC; High Order Statistics; LabVIEW; Implementation; Electronic Warfare; Cognitive Radio; AM; FM; PSK; QAM; Energy Analyzer; SNR

Eaton, Joy JeanAn investigation of extraterrestrial radio radiation in the cygnus region at 915 megacycles per second /
Doctor of Philosophy, The Ohio State University, 1957, Graduate School

Committee:

Not Provided (Other)

Subjects:

Engineering

Keywords:

Radio waves;Extraterrestrial radiation;Radio astronomy

Adams, Anthony AndrewPerspectives on community service responsibility of broadcast licensees /
Doctor of Philosophy, The Ohio State University, 1971, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Radio broadcasting;Radio broadcasting;Television broadcasting;Television broadcasting

Hirve, Sachin C.Multihop Transmission Opportunistic Protocol on Software Radio
Master of Science in Electrical Engineering, Cleveland State University, 2009, Fenn College of Engineering

The need of high speed communication motivates us to use high bit rate communication to transmit more information in as little time as possible. However, MAC layer protocol overheads dominate the transmission capability particularly at high rates and hinder high speed transmission. Opportunistic transmission has been proposed to help to overcome this disadvantage by transmitting packets back-to-back without inter-packet delays. Though this approach alleviates the problem in single-hop wireless LAN scenario, it doesn't help in multi-hop networks. This thesis presents an approach for multi-hop wireless networks, which is named as Multi-hop Transmission OPportunity (MTOP). It achieves better performance by ensuring better end-to-end packet transmission by allowing back-to-back packet transmission over multiple hops rather than that by one node.

Recent developments in wireless communication research have fueled verification of new approaches on real-life systems rather than simulation. In this thesis, the MTOP approach has been implemented and verified on a widely known software radio platform i.e. USRP hardware and GNU Radio open source software framework. Software radio has emerged as one of the potential platforms for future wireless applications. The wide spread acceptance of software radio is due to the flexibility achieved by porting complex hardware functions to software. This not only speeds up the development, but also creates the multi-standard support for wireless applications. The results show that MTOP improves network performance in a multi-rate ad-hoc network as compared to the contemporary approaches.

Committee:

Chansu Yu, Ph.D. (Advisor); Wenbing Zhao, Ph.D. (Committee Member); Vijay Konangi, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

Multihop wireless networks; USRP; Software Radio; GNU Radio

Lacki, Brian CameronCosmic Rays in Star-Forming Galaxies
Doctor of Philosophy, The Ohio State University, 2011, Astronomy

Cosmic rays (CRs) are high energy particles that are found wherever in the Universe star formation is occurring. I investigate several problems in the propagation of CRs in star-forming galaxies. By applying analytic models and numerically solving the “leaky box” differential equation, I calculate the population of primary and secondary CR protons, electrons and positrons in model star-forming galaxies and their nonthermal emission.

Observations show that the synchrotron radio emission of star-forming galaxies grows linearly with the infrared emission from dust-obscured young stars; this is the FIR-radio correlation (FRC). To explain the correlation, I constructed one-zone models of galaxies over the dynamic range of the FRC. I found that the FRC is caused by conspiracies of several factors, including CR escape from galaxies, ultraviolet (UV) dust opacity, non-synchrotron cooling, and secondary electrons and positrons generated by CR protons. The conspiracies have great implications for the evolution of the FRC at high redshift, preserving it and allowing variations in the FIR-radio ratio for submillimeter galaxies.

Recent gamma-ray observations of M82 and NGC 253 indicate that CR protons lose much of their energy to collisions in these galaxies’ dense gas, where they generate unstable pions that decay into gamma rays and secondary particles. The ratio of gamma-ray to radio luminosity indicates that secondary electrons mostly do not cool by synchrotron emission, supporting a conspiracy origin of the FRC.

I also compare the intensities of the diffuse cosmic gamma-ray background to the X-ray and radio backgrounds. From this comparison, I find that Inverse Compton is a minority of the X-ray background, and that the radio background is probably not from starbursts.

Finally, I modeled the nonthermal X-ray emission from starburst galaxies, both synchrotron from TeV electrons and Inverse Compton from GeV electrons. The synchrotron emission is enhanced by gamma-gamma pair production in the intense infrared radiation of starbursts. Synchrotron and Inverse Compton emission make up 1 - 10% of the observed diffuse hard X-ray emission observed in starburst galaxies.

Committee:

Todd Thompson (Committee Chair); John Beacom (Committee Member); Christopher Kochanek (Committee Member)

Subjects:

Astronomy; Astrophysics

Keywords:

cosmic rays; galaxies; radio emission from galaxies; gamma rays from galaxies; cosmic radio background; cosmic gamma-ray background

VIJAY, VIKASA TOP-DOWN METHODOLOGY FOR SYNTHESIS OF RF CIRCUITS
MS, University of Cincinnati, 2004, Engineering : Computer Engineering
This thesis presents automated techniques for synthesis of high performance RF circuits. The top-down methodology developed encompasses all stages of RF design from circuit sizing, layout generation to parasitic extraction and performance analysis. The objective of this methodology is to minimize the design time and generate efficient, correct and re-usable design solutions. In the proposed methodology, given a circuit netlist and a set of performance goals, a ready-to-tapeout layout is generated which meets the specified performance constraints. A sizing tool is integrated to perform design space exploration. A parameterized layout generator generates the layout based on the input sizes. An RF-Performance Analysis system (PAS-RF) comprising of a set of C++ functions is also developed for measuring the performance of the RF circuit. The proposed methodology is successfully tested by synthesizing variants of RF receiver circuits (LNA, Mixers, VCO etc.) for different performance criterion.

Committee:

Dr. Ranga Vemuri (Advisor)

Keywords:

Radio Frequency; Synthesis; Optimization; Automation; Layout Generation; RF; Analog; High Frequency; Module Generation; C++; SKILL; Extraction; Performance Analysis; Circuit Sizing; Radio Receiver; LNA; Mixer; VCO; Phase Frequency Detector

Ward, Rachel MendlPODCASTING IMPLEMENTATION IN PUBLIC RADIO
Master of Arts (MA), Ohio University, 2007, Telecommunications (Communication)

New technologies present both opportunities and challenges to public broadcasters. This thesis examines how one such technology, podcasting, is being broached by public radio broadcasters in the United States. An overview of public broadcasting and podcasting is provided. A survey was conducted to measure the perception of podcasting among public radio broadcasters, in keeping with diffusion of innovations theory. Three factors from diffusion theory, complexity, compatibility, and relative advantage were found to shape broadcasters' perceptions of podcasting. Two other attributes, social approval/communicability and cost are proposed for future research. A positive relationship between membership in the National Public Radio network and adoption of podcasting is found. Recommendations for implementing a pilot system of paid podcasting are shared.

Committee:

Gregory Newton (Advisor)

Subjects:

Mass Communications

Keywords:

podcasting; public radio; MP3; diffusion of innovations; public broadcasting; new media; National Public Radio; information technology

Shah, Kushal YogeshkumarComputational Complexity of Signal Processing Functions in Software Radio
Master of Science in Electrical Engineering, Cleveland State University, 2010, Fenn College of Engineering
The increased usage of mobile communication devices has imposed a challenge of achieving efficient communication with minimum power consumption. Moreover, with the advent of software defined radios (SDR), it is highly possible that signal processing functions would be implemented in software in future mobile devices. Hence, the power consumption of these future devices will be directly related to the power consumed by the processor that executes SDR software. This thesis aims at analyzing the computational complexity of different modulation schemes and signal processing communication functions of IEEE WiFi standard. This analysis provides good insight on how the computational load varies at different data rates for different modulation schemes. For this purpose, we have analyzed computational complexity of various modulation schemes and other communication functions using widely known software radio platform i.e. USRP hardware and GNU Radio open source software platform, Matlab and OProfile (open source Linux profiling tool). After performing an extensive analysis, we are able to determine how different modulation schemes and communication functions perform computationally on a given platform. This analysis would help to achieve effective communication along with the efficient use of power in SDR based systems.

Committee:

Chansu Yu, PhD (Committee Chair); Wenbing Zhao, PhD (Committee Member); Fuqin Xiong, PhD (Committee Member)

Subjects:

Computer Engineering; Electrical Engineering

Keywords:

Computational Complexity; Software Radio; Signal Processing Functions; GNU Radio; USRP

Chakravarthy, Vasu D.Evaluation of Overlay/Underlay Waveform via SD-SMSE Framework for Enhancing Spectrum Efficiency
Doctor of Philosophy (PhD), Wright State University, 2008, Engineering PhD

Recent studies have suggested that spectrum congestion is mainly due to the inefficient use of spectrum rather than its unavailability. Dynamic Spectrum Access (DSA) and Cognitive Radio (CR) are two terminologies which are used in the context of improved spectrum efficiency and usage. The DSA concept has been around for quite some time while the advent of CR has created a paradigm shift in wireless communications and instigated a change in FCC policy towards spectrum regulations. DSA can be broadly categorized as using a 1) Dynamic Exclusive Use Model, 2) Spectrum Commons or Open sharing model or 3) Hierarchical Access model. The hierarchical access model envisions primary licensed bands, to be opened up for secondary users, while inducing a minimum acceptable interference to primary users. Spectrum overlay and spectrum underlay technologies fall within the hierarchical model, and allow primary and secondary users to coexist while improving spectrum efficiency. Spectrum overlay in conjunction with the present CR model considers only the unused (white) spectral regions while in spectrum underlay the underused (gray) spectral regions are utilized. The underlay approach is similar to ultra wide band (UWB) and spread spectrum (SS) techniques utilize much wider spectrum and operate below the noise floor of primary users.

Software defined radio (SDR) is considered a key CR enabling technology. Spectrally modulated, Spectrally encoded (SMSE) multi-carrier signals such as Orthogonal Frequency Domain Multiplexing (OFDM) and Multi-carrier Code Division Multiple Access (MCCDMA) are hailed as candidate CR waveforms. The SMSE structure supports and is well-suited for SDR based CR applications. This work began by developing a general soft decision (SD) CR framework, based on a previously developed SMSE framework that combines benefits of both the overlay and underlay techniques to improve spectrum efficiency and maximizing the channel capacity. The resultant SD-SMSE framework provides a user with considerable flexibility to choose overlay, underlay or hybrid overlay/underlay waveform depending on the scenario, situation or need. Overlay/Underlay SD-SMSE framework flexibility is demonstrated by applying it to a family of SMSE modulated signals such as OFDM, MCCDMA, Carrier Interferometry (CI) MCCDMA and Transform Domain Communication System (TDCS). Based on simulation results, a performance analysis of Overlay, Underlay and hybrid Overlay/Underlay waveforms are presented. Finally, the benefits of combining overlay/underlay techniques to improve spectrum efficiency and maximize channel capacity are addressed.

Committee:

Arnab Shaw, PhD (Committee Co-Chair); Zhiqiang Wu, PhD (Committee Co-Chair); Fred Garber, PhD (Committee Member); Michael Temple, PhD (Committee Member); Michael Bryant, PhD (Committee Member)

Subjects:

Electrical Engineering

Keywords:

Dynamic Spectrum Access; Cognitive Radio; Overlay waveform; Underlay waveform; Software defined radio

Smith, Birna RichieAn investigation of radio station variables in relation to audience size /
Doctor of Philosophy, The Ohio State University, 1981, Graduate School

Committee:

Not Provided (Other)

Subjects:

Mass Communications

Keywords:

Radio stations;Radio audiences

Shen, TianningEXPERIMENTAL STUDY OF MULTIRATE MARGIN IN SOFTWARE DEFINED MULTIRATE RADIO
Master of Science in Electrical Engineering, Cleveland State University, 2009, Fenn College of Engineering

Due to the recent development of spectrally-efficient modulation schemes, IEEE 802.11 Wifi and IEEE 802.16 WiMax radios support wireless communication at multiple bit rates. While high-rate transmission allows delivering more information in less time, the corresponding performance improvement is less than expected due to the PHY- and MAC-layer overheads, imposed by the 802.11/16 standards. This is particularly true in wireless ad hoc networks as there exist rate-distance and rate-hop count tradeoffs.

The concept of multi-rate margin is proposed in this thesis, which exploits the difference in communication characteristics at different rates and serves as the fundamental ingredient for an opportunistic transmission protocol, targeted to meliorate the ad hoc mobile wireless network performance. In this thesis, the multi-rate margin is analyzed with theoretical derivation, perceived with simulation result using MATLAB and observed through real world testing using USRP and GNU Radio, which is a recent implementation of Software Defined Radio.

Committee:

Fuqin Xiong, PhD (Committee Chair); Chansu Yu, PhD (Committee Member); Pong Chu, PhD (Committee Member)

Keywords:

multi-rate; 802.11b; GNU Radio; multi-rate margin; RADIO; MTOP; DBPSK

Graessle, Robert JamesA Software-Defined Radio Based on the Unified SMSE Framework
Master of Science, Miami University, 2010, Computer Science and Systems Analysis
The purpose of this research was to implement a software-defined radio based on a recently developed framework for constructing various spectrally-modulated, spectrally-encoded (SMSE) signals. Two candidate waveforms (MC-CDMA and TDCS) are selected to demonstrate the capabilities of the framework, and they are modulated using antipodal signaling. A transmitter and receiver are each implemented on separate digital signal processor starting kits (DSK). A channel simulator consisting of additive white Gaussian noise and narrowband BPSK interferers is implemented on an FPGA. Burst transmissions from transmitter to receiver through the channel simulator are conducted to evaluate the bit-error rate performance of the system. Results from floating point simulation, fixed point simulation and hardware implementation are presented. The bit-error results from the hardware implementation closely match theoretical results. Also, TDCS is shown to mitigate effects of narrowband interference compared to MC-CDMA.

Committee:

Chi-Hao Cheng, PhD (Advisor); Dmitriy Garmatyuk, PhD (Committee Member); Vasu Chakravarthy, PhD (Committee Member)

Subjects:

Electrical Engineering

Keywords:

Cognitive radio; Software-defined radio; SMSE; MC-CDMA; TDCS

Mohr, Phillip JoeThe radio and television listening habits and program preferences of Eighth U.S. Army personnel in Korea, Autumn, 1959 /
Doctor of Philosophy, The Ohio State University, 1960, Graduate School

Committee:

Not Provided (Other)

Subjects:

Theater

Keywords:

Radio broadcasting;Television broadcasting;Television viewers;Radio audiences;Listening

Teso, William A.VLF propagation studies based on phase comparison records /
Doctor of Philosophy, The Ohio State University, 1964, Graduate School

Committee:

Not Provided (Other)

Subjects:

Engineering

Keywords:

Radio frequency;Ionospheric radio wave propagation

Carver, Keith R.A cavity-fed concentric ring phased array of helices for use in radio astronomy /
Doctor of Philosophy, The Ohio State University, 1968, Graduate School

Committee:

Not Provided (Other)

Subjects:

Engineering

Keywords:

Phased array antennas;Radio astronomy;Radio

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