ASU Electronic Theses and Dissertations
This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.
In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.
Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.
Displaying 31 - 40 of 92
Filtering by
- Creators: Ogras, Umit Y.
- Creators: Chassin, Laurie
Description
Historically, wireless communication devices have been developed to process one specific waveform. In contrast, a modern cellular phone supports multiple waveforms corresponding to LTE, WCDMA(3G) and 2G standards. The selection of the network is controlled by software running on a general purpose processor, not by the user. Now, instead of selecting from a set of complete radios as in software controlled radio, what if the software could select the building blocks based on the user needs. This is the new software-defined flexible radio which would enable users to construct wireless systems that fit their needs, rather than forcing to use from a small set of pre-existing protocols.
To develop and implement flexible protocols, a flexible hardware very similar to a Software Defined Radio (SDR) is required. In this thesis, the Intel T2200 board is chosen as the SDR platform. It is a heterogeneous platform with ARM, CEVA DSP and several accelerators. A wide range of protocols is mapped onto this platform and their performance evaluated. These include two OFDM based protocols (WiFi-Lite-A, WiFi-Lite-B), one DFT-spread OFDM based protocol (SCFDM-Lite) and one single carrier based protocol (SC-Lite). The transmitter and receiver blocks of the different protocols are first mapped on ARM in the T2200 board. The timing results show that IFFT, FFT, and Viterbi decoder blocks take most of the transmitter and receiver execution time and so in the next step these are mapped onto CEVA DSP. Mapping onto CEVA DSP resulted in significant execution time savings. The savings for WiFi-Lite-A were 60%, for WiFi-Lite-B were 64%, and for SCFDM-Lite were 71.5%. No savings are reported for SC-Lite since it was not mapped onto CEVA DSP.
Significant reduction in execution time is achieved for WiFi-Lite-A and WiFi-Lite-B protocols by implementing the entire transmitter and receiver chains on CEVA DSP. For instance, for WiFi-Lite-A, the savings were as large as 90%. Such huge savings are because the entire transmitter or receiver chain are implemented on CEVA and the timing overhead due to ARM-CEVA communication is completely eliminated. Finally, over-the-air testing was done for WiFi-Lite-A and WiFi-Lite-B protocols. Data was sent over the air using one Intel T2200 WBS board and received using another Intel T2200 WBS board. The received frames were decoded with no errors, thereby validating the over-the-air-communications.
To develop and implement flexible protocols, a flexible hardware very similar to a Software Defined Radio (SDR) is required. In this thesis, the Intel T2200 board is chosen as the SDR platform. It is a heterogeneous platform with ARM, CEVA DSP and several accelerators. A wide range of protocols is mapped onto this platform and their performance evaluated. These include two OFDM based protocols (WiFi-Lite-A, WiFi-Lite-B), one DFT-spread OFDM based protocol (SCFDM-Lite) and one single carrier based protocol (SC-Lite). The transmitter and receiver blocks of the different protocols are first mapped on ARM in the T2200 board. The timing results show that IFFT, FFT, and Viterbi decoder blocks take most of the transmitter and receiver execution time and so in the next step these are mapped onto CEVA DSP. Mapping onto CEVA DSP resulted in significant execution time savings. The savings for WiFi-Lite-A were 60%, for WiFi-Lite-B were 64%, and for SCFDM-Lite were 71.5%. No savings are reported for SC-Lite since it was not mapped onto CEVA DSP.
Significant reduction in execution time is achieved for WiFi-Lite-A and WiFi-Lite-B protocols by implementing the entire transmitter and receiver chains on CEVA DSP. For instance, for WiFi-Lite-A, the savings were as large as 90%. Such huge savings are because the entire transmitter or receiver chain are implemented on CEVA and the timing overhead due to ARM-CEVA communication is completely eliminated. Finally, over-the-air testing was done for WiFi-Lite-A and WiFi-Lite-B protocols. Data was sent over the air using one Intel T2200 WBS board and received using another Intel T2200 WBS board. The received frames were decoded with no errors, thereby validating the over-the-air-communications.
ContributorsChagari, Vamsi Reddy (Author) / Chakrabarti, Chaitali (Thesis advisor) / Lee, Hyunseok (Committee member) / Ogras, Umit Y. (Committee member) / Arizona State University (Publisher)
Created2016
Description
The present study aimed to test the effect of role socialization processes on declines in drinking after marriage. Role socialization as it relates to marriage theorizes that after occupying a role, individuals are likely to change their behaviors to conform to role expectations of marriage, such as reductions in drinking (Yamaguchi & Kandel, 1985). Previous literature has examined declines in drinking behaviors after marriage and inferred that role socialization was the underlying process. This study is the first to directly test whether beliefs that alcohol is harmful to the marital role predicted declines in frequency of drunkenness after marriage. Ordered probit regression was used to test the effect of marriage-related motives to limit drinking on declines in frequency of drunkenness from before marriage to after marriage. Analyses revealed that marriage-related motives to limit drinking were not significantly predictive of declines in frequency of drunkenness after marriage. Only partner drinking emerged as a significant predictor of declines in frequency of drunkenness after marriage. These results highlight the need for a reliable and valid measure of role socialization processes as they relate to the marital role. Furthermore, future studies should consider studying participants at different time points after marriage and consider measuring commitment to the marital role as a moderator. Such studies will help to better understand the results of this study as well as better understand the marriage effect on drinking.
ContributorsSternberg, Ariel (Author) / Chassin, Laurie (Thesis advisor) / Grimm, Kevin (Committee member) / Corbin, Will (Committee member) / Arizona State University (Publisher)
Created2016
Description
Adolescent substance use carries a considerable public health burden, and early initiation into use is especially problematic. Research has shown that sensation seeking traits increase risk for substance use experimentation, but less is known about individual and contextual factors that can potentially protect against this risk. This study utilized a longitudinal sub sample of youth (N=567) from a larger study of familial alcoholism to examine sensation seeking in early adolescence (ages 10-15) and its relations to later substance use experimentation. Hypotheses tested whether individual executive control, parenting consistency, neighborhood disadvantage, and neighborhood ethnic concentration moderated sensation seeking’s effects on substance use experimentation using multilevel zero-inflated Poisson modeling. Across models, higher levels of sensation seeking were predictive of a higher likelihood of having initiated substance use, but sensation seeking was not significantly related to the number of different substance use classes tried. Only neighborhood disadvantage emerged as a significant moderator of the path from sensation seeking to substance use initiation. The strength of sensation seeking effects on substance use initiation increased as neighborhood disadvantage decreased below average levels, with the most advantaged neighborhoods exhibiting the strongest link between sensation seeking and substance use. There was also a trend towards the most disadvantaged neighborhoods exhibiting increased sensation seeking effects on substance use initiation. These results highlight the importance of focusing on relatively more advantaged areas as potentially risky environments for the externalizing pathway to substance use.
ContributorsJensen, Michaeline R (Author) / Gonzales, Nancy A. (Thesis advisor) / Chassin, Laurie (Thesis advisor) / Enders, Craig (Committee member) / White, Rebecca (Committee member) / Arizona State University (Publisher)
Created2016
Description
Clock generation and distribution are essential to CMOS microchips, providing synchronization to external devices and between internal sequential logic. Clocks in microprocessors are highly vulnerable to single event effects and designing reliable energy efficient clock networks for mission critical applications is a major challenge. This dissertation studies the basics of radiation hardening, essentials of clock design and impact of particle strikes on clocks in detail and presents design techniques for hardening complete clock systems in digital ICs.
Since the sequential elements play a key role in deciding the robustness of any clocking strategy, hardened-by-design implementations of triple-mode redundant (TMR) pulse clocked latches and physical design methodologies for using TMR master-slave flip-flops in application specific ICs (ASICs) are proposed. A novel temporal pulse clocked latch design for low power radiation hardened applications is also proposed. Techniques for designing custom RHBD clock distribution networks (clock spines) and ASIC clock trees for a radiation hardened microprocessor using standard CAD tools are presented. A framework for analyzing the vulnerabilities of clock trees in general, and study the parameters that contribute the most to the tree’s failure, including impact on controlled latches is provided. This is then used to design an integrated temporally redundant clock tree and pulse clocked flip-flop based clocking scheme that is robust to single event transients (SETs) and single event upsets (SEUs). Subsequently, designing robust clock delay lines for use in double data rate (DDRx) memory applications is studied in detail. Several modules of the proposed radiation hardened all-digital delay locked loop are designed and studied. Many of the circuits proposed in this entire body of work have been implemented and tested on a standard low-power 90-nm process.
Since the sequential elements play a key role in deciding the robustness of any clocking strategy, hardened-by-design implementations of triple-mode redundant (TMR) pulse clocked latches and physical design methodologies for using TMR master-slave flip-flops in application specific ICs (ASICs) are proposed. A novel temporal pulse clocked latch design for low power radiation hardened applications is also proposed. Techniques for designing custom RHBD clock distribution networks (clock spines) and ASIC clock trees for a radiation hardened microprocessor using standard CAD tools are presented. A framework for analyzing the vulnerabilities of clock trees in general, and study the parameters that contribute the most to the tree’s failure, including impact on controlled latches is provided. This is then used to design an integrated temporally redundant clock tree and pulse clocked flip-flop based clocking scheme that is robust to single event transients (SETs) and single event upsets (SEUs). Subsequently, designing robust clock delay lines for use in double data rate (DDRx) memory applications is studied in detail. Several modules of the proposed radiation hardened all-digital delay locked loop are designed and studied. Many of the circuits proposed in this entire body of work have been implemented and tested on a standard low-power 90-nm process.
ContributorsChellappa, Srivatsan (Author) / Clark, Lawrence T (Thesis advisor) / Holbert, Keith E. (Committee member) / Cao, Yu (Committee member) / Ogras, Umit Y. (Committee member) / Arizona State University (Publisher)
Created2015
Description
Power Management circuits are employed in almost all electronic equipment and they have energy storage elements (capacitors and inductors) as building blocks along with other active circuitry. Power management circuits employ feedback to achieve good load and line regulation. The feedback loop is designed at an operating point and component values are chosen to meet that design requirements. But the capacitors and inductors are subject to variations due to temperature, aging and load stress. Due to these variations, the feedback loop can cross its robustness margins and can lead to degraded performance and potential instability. Another issue in power management circuits is the measurement of their frequency response for stability assessment. The standard techniques used in production test environment require expensive measurement equipment (Network Analyzer) and time. These two issues of component variations and frequency response measurement can be addressed if the frequency response of the power converter is used as measure of component (capacitor and inductor) variations. So, a single solution of frequency response measurement solves both the issues. This work examines system identification (frequency response measurement) of power management circuits based on cross correlation technique and proposes the use of switched capacitor correlator for this purpose. A switched capacitor correlator has been designed and used in the system identification of Linear and Switching regulators. The obtained results are compared with the standard frequency response measurement methods of power converters.
ContributorsMalladi, Venkata Naga Koushik (Author) / Bakkaloglu, Bertan (Thesis advisor) / Kitchen, Jennifer (Committee member) / Ogras, Umit Y. (Committee member) / Arizona State University (Publisher)
Created2015
Description
The reduced availability of 3He is a motivation for developing alternative neutron detectors. 6Li-enriched CLYC (Cs2LiYCl6), a scintillator, is a promising candidate to replace 3He. The neutron and gamma ray signals from CLYC have different shapes due to the slower decay of neutron pulses. Some of the well-known pulse shape discrimination techniques are charge comparison method, pulse gradient method and frequency gradient method. In the work presented here, we have applied a normalized cross correlation (NCC) approach to real neutron and gamma ray pulses produced by exposing CLYC scintillators to a mixed radiation environment generated by 137Cs, 22Na, 57Co and 252Cf/AmBe at different event rates. The cross correlation analysis produces distinctive results for measured neutron pulses and gamma ray pulses when they are cross correlated with reference neutron and/or gamma templates. NCC produces good separation between neutron and gamma rays at low (< 100 kHz) to mid event rate (< 200 kHz). However, the separation disappears at high event rate (> 200 kHz) because of pileup, noise and baseline shift. This is also confirmed by observing the pulse shape discrimination (PSD) plots and figure of merit (FOM) of NCC. FOM is close to 3, which is good, for low event rate but rolls off significantly along with the increase in the event rate and reaches 1 at high event rate. Future efforts are required to reduce the noise by using better hardware system, remove pileup and detect the NCC shapes of neutron and gamma rays using advanced techniques.
ContributorsChandhran, Premkumar (Author) / Holbert, Keith E. (Thesis advisor) / Spanias, Andreas (Committee member) / Ogras, Umit Y. (Committee member) / Arizona State University (Publisher)
Created2015
Description
RF transmitter manufacturers go to great extremes and expense to ensure that their product meets the RF output power requirements for which they are designed. Therefore, there is an urgent need for in-field monitoring of output power and gain to bring down the costs of RF transceiver testing and ensure product reliability. Built-in self-test (BIST) techniques can perform such monitoring without the requirement for expensive RF test equipment. In most BIST techniques, on-chip resources, such as peak detectors, power detectors, or envelope detectors are used along with frequency down conversion to analyze the output of the design under test (DUT). However, this conversion circuitry is subject to similar process, voltage, and temperature (PVT) variations as the DUT and affects the measurement accuracy. So, it is important to monitor BIST performance over time, voltage and temperature, such that accurate in-field measurements can be performed.
In this research, a multistep BIST solution using only baseband signals for test analysis is presented. An on-chip signal generation circuit, which is robust with respect to time, supply voltage, and temperature variations is used for self-calibration of the BIST system before the DUT measurement. Using mathematical modelling, an analytical expression for the output signal is derived first and then test signals are devised to extract the output power of the DUT. By utilizing a standard 180nm IBM7RF CMOS process, a 2.4GHz low power RF IC incorporated with the proposed BIST circuitry and on-chip test signal source is designed and fabricated. Experimental results are presented, which show this BIST method can monitor the DUT’s output power with +/- 0.35dB accuracy over a 20dB power dynamic range.
In this research, a multistep BIST solution using only baseband signals for test analysis is presented. An on-chip signal generation circuit, which is robust with respect to time, supply voltage, and temperature variations is used for self-calibration of the BIST system before the DUT measurement. Using mathematical modelling, an analytical expression for the output signal is derived first and then test signals are devised to extract the output power of the DUT. By utilizing a standard 180nm IBM7RF CMOS process, a 2.4GHz low power RF IC incorporated with the proposed BIST circuitry and on-chip test signal source is designed and fabricated. Experimental results are presented, which show this BIST method can monitor the DUT’s output power with +/- 0.35dB accuracy over a 20dB power dynamic range.
ContributorsGangula, Sudheer Kumar Reddy (Author) / Kitchen, Jennifer (Thesis advisor) / Ozev, Sule (Committee member) / Ogras, Umit Y. (Committee member) / Arizona State University (Publisher)
Created2015
Description
The present study tested the respective mediating effects of sensation seeking and initial level of response (LR) to negative, sedative alcohol effects on the relation between the density of familial history of alcoholism and adolescent alcohol use. Additionally, the present study tested the direct effect of LR to negative, sedative alcohol effects on adolescent drinking over and above the effects of sensation seeking; and also tested the moderating effect of sensation seeking on the relation between level of response negative, sedative alcohol effects and adolescent drinking. Specifically, OLS regression models first estimated the effects of sensation seeking, LR to negative, sedative alcohol effects, and their interaction on alcohol outcomes, over and above the influence of covariates. Indirect effects were then tested using the PRODCLIN method through RMediation. Analyses failed to support sensation seeking as a mediator in the relation between familial history of alcoholism and adolescent drinking, and as a moderator of the relation between LR and adolescent drinking. However, analyses did support a robust direct effect of LR to negative, sedative alcohol effects on adolescent alcohol involvement. A significant mediating effect of initial LR to negative, sedative alcohol effects on the relation between familial alcoholism and adolescent drinking was found, however failed to maintain significance in post-hoc analyses attenuating the downward bias of the measure of initial LR. Initial LR to negative, sedative alcohol effects continued to predict adolescent drinking after attenuating measure bias. These findings strengthen research on initial LR to negative, sedative alcohol effects as a risk for greater alcohol involvement in adolescence, and underscore the complexity of studying the familial transmission of alcoholism in adolescent populations
ContributorsPandika, Danielle (Author) / Chassin, Laurie (Thesis advisor) / Corbin, William (Committee member) / Aiken, Leona (Committee member) / Arizona State University (Publisher)
Created2015
Description
Due to high level of integration in RF System on Chip (SOC), the test access points are limited to the baseband and RF inputs/outputs of the system. This limited access poses a big challenge particularly for advanced RF architectures where calibration of internal parameters is necessary and ensure proper operation. Therefore low-overhead built-in Self-Test (BIST) solution for advanced RF transceiver is proposed. In this dissertation. Firstly, comprehensive BIST solution for RF polar transceivers using on-chip resources is presented. In the receiver, phase and gain mismatches degrade sensitivity and error vector magnitude (EVM). In the transmitter, delay skew between the envelope and phase signals and the finite envelope bandwidth can create intermodulation distortion (IMD) that leads to violation of spectral mask requirements. Characterization and calibration of these parameters with analytical model would reduce the test time and cost considerably. Hence, a technique to measure and calibrate impairments of the polar transceiver in the loop-back mode is proposed.
Secondly, robust amplitude measurement technique for RF BIST application and BIST circuits for loop-back connection are discussed. Test techniques using analytical model are explained and BIST circuits are introduced.
Next, a self-compensating built-in self-test solution for RF Phased Array Mismatch is proposed. In the proposed method, a sinusoidal test signal with unknown amplitude is applied to the inputs of two adjacent phased array elements and measure the baseband output signal after down-conversion. Mathematical modeling of the circuit impairments and phased array behavior indicates that by using two distinct input amplitudes, both of which can remain unknown, it is possible to measure the important parameters of the phased array, such as gain and phase mismatch. In addition, proposed BIST system is designed and fabricated using IBM 180nm process and a prototype four-element phased-array PCB is also designed and fabricated for verifying the proposed method.
Finally, process independent gain measurement via BIST/DUT co-design is explained. Design methodology how to reduce performance impact significantly is discussed.
Simulation and hardware measurements results for the proposed techniques show that the proposed technique can characterize the targeted impairments accurately.
Secondly, robust amplitude measurement technique for RF BIST application and BIST circuits for loop-back connection are discussed. Test techniques using analytical model are explained and BIST circuits are introduced.
Next, a self-compensating built-in self-test solution for RF Phased Array Mismatch is proposed. In the proposed method, a sinusoidal test signal with unknown amplitude is applied to the inputs of two adjacent phased array elements and measure the baseband output signal after down-conversion. Mathematical modeling of the circuit impairments and phased array behavior indicates that by using two distinct input amplitudes, both of which can remain unknown, it is possible to measure the important parameters of the phased array, such as gain and phase mismatch. In addition, proposed BIST system is designed and fabricated using IBM 180nm process and a prototype four-element phased-array PCB is also designed and fabricated for verifying the proposed method.
Finally, process independent gain measurement via BIST/DUT co-design is explained. Design methodology how to reduce performance impact significantly is discussed.
Simulation and hardware measurements results for the proposed techniques show that the proposed technique can characterize the targeted impairments accurately.
ContributorsJeong, Jae Woong (Author) / Ozev, Sule (Thesis advisor) / Kitchen, Jennifer (Committee member) / Cao, Yu (Committee member) / Ogras, Umit Y. (Committee member) / Arizona State University (Publisher)
Created2015
Description
ABSTRACT
Designers creating the next generation remote sensing enabled smart devices need to overcome the challenges of prevailing ventures including time to market and expense.
To reduce the time and effort involved in initial prototyping, a good reference design is often desired and warranted. This paper provides the necessary reference materials for Designers to implement a wireless solution efficiently and effectively.
This document is intended for users with limited Bluetooth technology experience.
Many sensing-enabled devices require a ‘hard-wire’ or cable link to a host monitoring system. This can limit the potential for product advancements by anchoring the system to a single location preventing portability and the convenience of a remote system. By removing the “wired” or cabled portion from a design, a broader scope of devices becomes feasible.
One common problematic area for these types of sensors is within the internal medicine field. Proximity sensing is far more practical and less invasive to implement than surgical implantation. Bluetooth Low Energy (BLE) systems solve the hard wired problem by decoupling the physical sensor from the host system through a BLE transceiver that can send information to an external monitoring system. This wireless link enables new sensor technology to be leveraged into previously unobtainable markets; such as, internal medicine, wearable devices, and Infotainment to name a few. Wireless technology for sensor systems are a potentially disruptive technology changing the way environmental monitoring is implemented and considered.
With this BLE design reference, products can be created with new capabilities to advance current technologies for military, commercial, industrial and medical sectors in rapid succession.
Designers creating the next generation remote sensing enabled smart devices need to overcome the challenges of prevailing ventures including time to market and expense.
To reduce the time and effort involved in initial prototyping, a good reference design is often desired and warranted. This paper provides the necessary reference materials for Designers to implement a wireless solution efficiently and effectively.
This document is intended for users with limited Bluetooth technology experience.
Many sensing-enabled devices require a ‘hard-wire’ or cable link to a host monitoring system. This can limit the potential for product advancements by anchoring the system to a single location preventing portability and the convenience of a remote system. By removing the “wired” or cabled portion from a design, a broader scope of devices becomes feasible.
One common problematic area for these types of sensors is within the internal medicine field. Proximity sensing is far more practical and less invasive to implement than surgical implantation. Bluetooth Low Energy (BLE) systems solve the hard wired problem by decoupling the physical sensor from the host system through a BLE transceiver that can send information to an external monitoring system. This wireless link enables new sensor technology to be leveraged into previously unobtainable markets; such as, internal medicine, wearable devices, and Infotainment to name a few. Wireless technology for sensor systems are a potentially disruptive technology changing the way environmental monitoring is implemented and considered.
With this BLE design reference, products can be created with new capabilities to advance current technologies for military, commercial, industrial and medical sectors in rapid succession.
ContributorsHughes, Clinton Francis (Author) / Blain Christen, Jennifer (Thesis advisor) / Ozev, Sule (Committee member) / Ogras, Umit Y. (Committee member) / Aberle, James T., 1961- (Committee member) / Arizona State University (Publisher)
Created2015