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- Genre: Doctoral Dissertation
- Creators: Bakkaloglu, Bertan
- Creators: Gu, Bin
- Creators: Rockmaker, Jody
Description
Distributed estimation uses many inexpensive sensors to compose an accurate estimate of a given parameter. It is frequently implemented using wireless sensor networks. There have been several studies on optimizing power allocation in wireless sensor networks used for distributed estimation, the vast majority of which assume linear radio-frequency amplifiers. Linear amplifiers are inherently inefficient, so in this dissertation nonlinear amplifiers are examined to gain efficiency while operating distributed sensor networks. This research presents a method to boost efficiency by operating the amplifiers in the nonlinear region of operation. Operating amplifiers nonlinearly presents new challenges. First, nonlinear amplifier characteristics change across manufacturing process variation, temperature, operating voltage, and aging. Secondly, the equations conventionally used for estimators and performance expectations in linear amplify-and-forward systems fail. To compensate for the first challenge, predistortion is utilized not to linearize amplifiers but rather to force them to fit a common nonlinear limiting amplifier model close to the inherent amplifier performance. This minimizes the power impact and the training requirements for predistortion. Second, new estimators are required that account for transmitter nonlinearity. This research derives analytically and confirms via simulation new estimators and performance expectation equations for use in nonlinear distributed estimation. An additional complication when operating nonlinear amplifiers in a wireless environment is the influence of varied and potentially unknown channel gains. The impact of these varied gains and both measurement and channel noise sources on estimation performance are analyzed in this paper. Techniques for minimizing the estimate variance are developed. It is shown that optimizing transmitter power allocation to minimize estimate variance for the most-compressed parameter measurement is equivalent to the problem for linear sensors. Finally, a method for operating distributed estimation in a multipath environment is presented that is capable of developing robust estimates for a wide range of Rician K-factors. This dissertation demonstrates that implementing distributed estimation using nonlinear sensors can boost system efficiency and is compatible with existing techniques from the literature for boosting efficiency at the system level via sensor power allocation. Nonlinear transmitters work best when channel gains are known and channel noise and receiver noise levels are low.
ContributorsSantucci, Robert (Author) / Spanias, Andreas (Thesis advisor) / Tepedelenlioðlu, Cihan (Committee member) / Bakkaloglu, Bertan (Committee member) / Tsakalis, Kostas (Committee member) / Arizona State University (Publisher)
Created2013
Description
Bright Summer, a one-movement piece for orchestra, was composed in Arizona, and completed in February 2013. The piece is approximately twelve minutes long. The motivation for writing this piece was the death of my mother the year before, in 2012. The prevailing mood of this work is bright and pleasant, expressing my mother's cheerful personality when she was alive. It also portrays bright summer days which resemble my mother's spirit. Thus, soundscape plays an important role in this work. It depicts summer breeze, rustling sounds of leaves, and, to translate a Korean saying, "high blue skies." This soundscape opens the piece as well as closes it. In the middle section, the fast upbeat themes represent my mother's witty and optimistic personality. The piece also contains the presence of a hymn tune, The Love of God is Greater Far, which informs the motivic content and also functions as the climax of the piece. It was my mother's favorite hymn and we used to sing it together following her conversion to Christianity. The piece contains three main sections, which are held together by transitional material based on the soundscape and metric modulations. Unlike my earlier works, Bright Summer is tonal, with upper tertian harmonies prevailing throughout the piece. However, the opening and closing soundscapes do not have functional harmonies. For example, tertian chords appear and vanish silently, leaving behind some resonant sounds without any harmonic progression. Overall, the whole piece is reminiscent of my mother who lived a beautiful life.
ContributorsKim, JeeYeon (Composer) / DeMars, James (Thesis advisor) / Hackbarth, Glenn (Committee member) / Rogers, Rodney (Committee member) / Levy, Benjamin (Committee member) / Rockmaker, Jody (Committee member) / Arizona State University (Publisher)
Created2013
Description
Radio frequency (RF) transceivers require a disproportionately high effort in terms of test development time, test equipment cost, and test time. The relatively high test cost stems from two contributing factors. First, RF transceivers require the measurement of a diverse set of specifications, requiring multiple test set-ups and long test times, which complicates load-board design, debug, and diagnosis. Second, high frequency operation necessitates the use of expensive equipment, resulting in higher per second test time cost compared with mixed-signal or digital circuits. Moreover, in terms of the non-recurring engineering cost, the need to measure complex specfications complicates the test development process and necessitates a long learning process for test engineers. Test time is dominated by changing and settling time for each test set-up. Thus, single set-up test solutions are desirable. Loop-back configuration where the transmitter output is connected to the receiver input are used as the desirable test set- up for RF transceivers, since it eliminates the reliance on expensive instrumentation for RF signal analysis and enables measuring multiple parameters at once. In-phase and Quadrature (IQ) imbalance, non-linearity, DC offset and IQ time skews are some of the most detrimental imperfections in transceiver performance. Measurement of these parameters in the loop-back mode is challenging due to the coupling between the receiver (RX) and transmitter (TX) parameters. Loop-back based solutions are proposed in this work to resolve this issue. A calibration algorithm for a subset of the above mentioned impairments is also presented. Error Vector Magnitude (EVM) is a system-level parameter that is specified for most advanced communication standards. EVM measurement often takes extensive test development efforts, tester resources, and long test times. EVM is analytically related to system impairments, which are typically measured in a production test i environment. Thus, EVM test can be eliminated from the test list if the relations between EVM and system impairments are derived independent of the circuit implementation and manufacturing process. In this work, the focus is on the WLAN standard, and deriving the relations between EVM and three of the most detrimental impairments for QAM/OFDM based systems (IQ imbalance, non-linearity, and noise). Having low cost test techniques for measuring the RF transceivers imperfections and being able to analytically compute EVM from the measured parameters is a complete test solution for RF transceivers. These techniques along with the proposed calibration method can be used in improving the yield by widening the pass/fail boundaries for transceivers imperfections. For all of the proposed methods, simulation and hardware measurements prove that the proposed techniques provide accurate characterization of RF transceivers.
ContributorsNassery, Afsaneh (Author) / Ozev, Sule (Thesis advisor) / Bakkaloglu, Bertan (Committee member) / Kiaei, Sayfe (Committee member) / Kitchen, Jennifer (Committee member) / Arizona State University (Publisher)
Created2013
Description
Social media offers a powerful platform for the independent digital content producer community to develop, disperse, and maintain their brands. In terms of information systems research, the broad majority of the work has not examined hedonic consumption on Social Media Sites (SMS). The focus has mostly been on the organizational perspectives and utilitarian gains from these services. Unlike through traditional commerce channels, including e-commerce retailers, consumption enhancing hedonic utility is experienced differently in the context of a social media site; consequently, the dynamic of the decision-making process shifts when it is made in a social context. Previous research assumed a limited influence of a small, immediate group of peers. But the rules change when the network of peers expands exponentially. The assertion is that, while there are individual differences in the level of susceptibility to influence coming from others, these are not the most important pieces of the analysis--unlike research centered completely on influence. Rather, the context of the consumption can play an important role in the way social influence factors affect consumer behavior on Social Media Sites. Over the course of three studies, this dissertation will examine factors that influence consumer decision-making and the brand personalities created and interpreted in these SMS. Study one examines the role of different types of peer influence on consumer decision-making on Facebook. Study two observes the impact of different types of producer message posts with the different types of influence on decision-making on Twitter. Study three will conclude this work with an exploratory empirical investigation of actual twitter postings of a set of musicians. These studies contribute to the body of IS literature by evaluating the specific behavioral changes related to consumption in the context of digital social media: (a) the power of social influencers in contrast to personal preferences on SMS, (b) the effect on consumers of producer message types and content on SMS at both the profile level and the individual message level.
ContributorsSopha, Matthew (Author) / Santanam, Raghu T (Thesis advisor) / Goul, Kenneth M (Committee member) / Gu, Bin (Committee member) / Arizona State University (Publisher)
Created2013
Description
Norwegian composer Ola Gjeilo (b. 1978) is highly regarded as an accomplished and prolific composer of choral music. His creative output includes works for chorus, solo piano, and wind symphony. His unique style infuses elements of cinematic music, jazz and improvisation, with particularly intriguing selections of text. This study examines the factors that influence Gjeilo's compositional techniques, and the musical interpretations of conductor Charles Bruffy in his preparation for The Phoenix Chorale's recording Northern Lights: Choral Works by Ola Gjeilo. The eleven works discussed in this study are: The Ground, Evening Prayer, Ubi caritas, Prelude, Northern Lights, The Spheres, Tota pulchra es, Serenity, Phoenix (Agnus Dei), Unicornis captivatur, and Dark Night of the Soul. As a relatively new and young composer, there is very little published literature on Gjeilo and his works. This study provides an intimate glance into the creative process of the composer. By composing in multiple styles and with a variety of inspirational sources, Gjeilo creates a fresh approach toward composition of new choral music. His style is revealed through interviews and numerous collaborations with conductors and performers who have prepared and performed his music, as well through an examination of the eleven works recorded by The Phoenix Chorale.
ContributorsGarrison, Ryan Derrick (Author) / Reber, William (Thesis advisor) / Saucier, Catherine (Committee member) / Rockmaker, Jody (Committee member) / Doan, Jerry (Committee member) / Arizona State University (Publisher)
Created2013
Description
This thesis presents a new arrangement of Richard Peaslee's trombone solo "Arrows of Time" for brass band. This arrangement adapts Peaslee's orchestration - and subsequent arrangement by Dr. Joshua Hauser for wind ensemble - for the modern brass band instrumentation and includes a full score. A brief biography of Richard Peaslee and his work accompanies this new arrangement, along with commentary on the orchestration of "Arrows of Time", and discussion of the evolution and adaptation of the work for wind ensemble by Dr. Hauser. The methodology used to adapt these versions for the brass band completes the background information.
ContributorsMalloy, Jason Patrick (Author) / Ericson, John (Thesis advisor) / Oldani, Robert (Committee member) / Rockmaker, Jody (Committee member) / Arizona State University (Publisher)
Created2013
Description
The medical industry has benefited greatly by electronic integration resulting in the explosive growth of active medical implants. These devices often treat and monitor chronic health conditions and require very minimal power usage. A key part of these medical implants is an ultra-low power two way wireless communication system. This enables both control of the implant as well as relay of information collected. This research has focused on a high performance receiver for medical implant applications. One commonly quoted specification to compare receivers is energy per bit required. This metric is useful, but incomplete in that it ignores Sensitivity level, bit error rate, and immunity to interferers. In this study exploration of receiver architectures and convergence upon a comprehensive solution is done. This analysis is used to design and build a system for validation. The Direct Conversion Receiver architecture implemented for the MICS standard in 0.18 µm CMOS process consumes approximately 2 mW is competitive with published research.
ContributorsStevens, Mark (Author) / Kiaei, Sayfe (Thesis advisor) / Bakkaloglu, Bertan (Committee member) / Aberle, James T., 1961- (Committee member) / Barnaby, Hugh (Committee member) / Arizona State University (Publisher)
Created2012
Description
Test cost has become a significant portion of device cost and a bottleneck in high volume manufacturing. Increasing integration density and shrinking feature sizes increased test time/cost and reduce observability. Test engineers have to put a tremendous effort in order to maintain test cost within an acceptable budget. Unfortunately, there is not a single straightforward solution to the problem. Products that are tested have several application domains and distinct customer profiles. Some products are required to operate for long periods of time while others are required to be low cost and optimized for low cost. Multitude of constraints and goals make it impossible to find a single solution that work for all cases. Hence, test development/optimization is typically design/circuit dependent and even process specific. Therefore, test optimization cannot be performed using a single test approach, but necessitates a diversity of approaches. This works aims at addressing test cost minimization and test quality improvement at various levels. In the first chapter of the work, we investigate pre-silicon strategies, such as design for test and pre-silicon statistical simulation optimization. In the second chapter, we investigate efficient post-silicon test strategies, such as adaptive test, adaptive multi-site test, outlier analysis, and process shift detection/tracking.
ContributorsYilmaz, Ender (Author) / Ozev, Sule (Thesis advisor) / Bakkaloglu, Bertan (Committee member) / Cao, Yu (Committee member) / Christen, Jennifer Blain (Committee member) / Arizona State University (Publisher)
Created2012
Description
The German pianist and composer Johannes Brahms (1883-1897) wrote more than 122 works for a wide variety of ensembles and genres. Despite this remarkable productivity, and his widely heralded talent for innovation and technique as a composer, few of his works have been arranged for solo guitar, and these have focused primarily on his simpler, more melodic works. Conventional wisdom is that his music is "too dense" to be played on the guitar. As a result, there are no arrangements of orchestral works by Brahms in the standard repertoire for the guitar. In arranging Brahms's Serenade in D Major, movt. 1 for the guitar, I provide a counter argument that not all of Brahms's orchestral music is too dense all of the time. In Part I, I provide a brief overview of the history of, and sources for, the Serenade. Part II describes a step-by-step guide through the process of arranging orchestral repertoire for the solo guitar. Part III is an examination of the editing process that utilizes examples from the guitar arrangement of the Serenade in order to illustrate the various techniques and considerations that are part of the editing process. Part IV is a performance edition of the arrangement. In summary, the present arrangement of Brahms's Serenade, op.11 is the beginning of a conversation about why the "guitar world" should be incorporating the music of Brahms into the standard repertoire. The lessons learned, and the technical challenges discovered, should help inform future arrangers and guitar performers for additional compositions by Brahms.
ContributorsLanier, William Hudson (Author) / Koonce, Frank (Thesis advisor) / Micklich, Albie (Committee member) / Rockmaker, Jody (Committee member) / Arizona State University (Publisher)
Created2013
Description
Nelson Rolihlahla Mandela was born July 18, 1918 into the Madiba clan in Mvezo, Transkei, South Africa. Mandela was a lawyer by trade and a freedom fighter who envisioned freedom and equality for all South Africans regardless of race. In 1965, Mandela was imprisoned at Robben Island for twenty-seven years for treason and terrorist activities against the South African apartheid regime: he was assigned prison numbers 46664. In 1992, Mandela was released from prison and two years later not only became the first democratically elected president of South Africa, but also its first black president. "Madiba 46664" is an eight-minute chamber work scored for flute, oboe, clarinet in B-flat, and bassoon; vibraphone, and two percussionists; piano; violins, violas, and celli. The work blends traditional South African rhythms of the drumming culture with elements of Western harmony and form in contrasting textures of homophony, polyphony and antiphony. "Madiba 46664" utilizes Mandela's prison number, birthdate and age (at the time the composition process began in 2013) for the initial generation of meter, rhythm, harmony, melody, and form. The work also shares intercultural concepts that can be seen in the works of three contemporary African composers, South Africans Jeanne Zaidel-Rudolph and Andile Khumalo, and Nigerian Ayo Oluranti. Each section represents a period of Mandela's life as a freedom fighter, a prisoner, and a president. The inspiration stems from the composer's discussions with Mandela soon after his release from prison and prior to his presidency. These lively discussions pertained to the state of traditional music in then apartheid South Africa and led to this creation. The conversations also played a role in the creative process.
ContributorsMabingnai, Collette Sipho (Composer) / DeMars, James (Thesis advisor) / Hackbarth, Glenn (Committee member) / Humphreys, Jere (Committee member) / Rockmaker, Jody (Committee member) / Rogers, Rodney (Committee member) / Arizona State University (Publisher)
Created2014