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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An Efficient Arithmetic Sum-of-Product (SOP) based Multiplication Approach for FIR Filters and DFT

Kumar, Rajeev 03 October 2013 (has links)
Discrete Fourier Transform (DFT) and Finite Impulse Response (FIR) filters are extensively used in Digital Signal Processing (DSP) and Image Processing. As a result, there is a strong motivation to come up with area- and delay-efficient hardware realizations of DFT and FIR filters. In this thesis, we propose an arithmetic Sum-of-Product (SOP) based approach to implement area- and delay-efficient Discrete Fourier Transform (DFT) and FIR filter circuits. Our SOP based engine uses an improved column compression algorithm, and handles the sign of the input efficiently. The partial products of the computation are compressed down to 2 operands, which are then added using a single hybrid adder (which is comprised of a ripple carry adder for the early-arriving lower-order bits, a Kogge-Stone adder for the slower middle bits, and a carry-select adder for the early-arriving higher order bits). The DFT and FIR filters can also be cast as instances of the Multiple Constant Multiplication (MCM) problem. RAG-n is one of the best known algorithms for realizing an MCM block with the minimum number of adders. We compare our SOP-based implementations with the RAG-n algorithm. We implement both approaches using a 45 nm cell library, and demonstrate that our approach yields a faster DFT circuit (by about 12-13%), with a small (about 5%) area penalty and a significantly better algorithmic runtime. We also demonstrate that our approach realizes FIR filters with hard-to-implement coefficients with a 4.4× speedup and 1.38× area penalty as compared to two recent adder cascade based approaches. For a set of symmetric and asymmetric filters, we compare the area-delay curves of the circuits generated by using our SOP based approach with that of the circuits generated by using a Common Sub-expression Elimination (CSE) based algorithm, which tries to minimize the number of adders utilized under a maximum adder cascade length constraint. We show that for a large range of delays, the circuits generated by using our approach have the smallest area. Finally, we propose a new hybrid form realization for FIR filters. The hybrid form realization attempts to perform the computation using both the Direct and Transposed Direct form realization styles. We discuss conditions under which it would improve on both the Direct and Transposed Direct form realizations, in terms of circuit area and delay.
2

A Biomechanical Comparison of Unilateral and Bilateral String-Of-Pearls Locking Plates in a Canine Distal Humeral Metaphyseal Gap Model

Hurt, Richard J 15 August 2014 (has links)
Humeral fractures in veterinary patients are challenging to stabilize. This study is a biomechanical in vitro comparison of the performance of two locking plate constructs used to stabilize a canine distal humeral metaphyseal gap model. Two groups of canine cadaveric humeri were prepared. One group consisted of a unilateral medially placed locking plate (UNI). The second group consisted of bilateral locking plates (BI). Constructs were tested in torsion and axial compression. The UNI constructs had significantly lower stiffness in torsion and axial compression than the BI group. However, UNI constructs had a significantly higher ultimate strength than BI constructs. All UNI constructs failed by bending of the transcondylar screw and SOP plate. All BI constructs failed by axial pullout of the distal most screws. The clinical significance is that in stabilizing canine supracondylar humeral fractures as modeled here, both the UNI model and the BI model demonstrated biomechanical advantages.
3

Automatic Generation of Control Code for Flexible Automation / Automatgenerering av kod för flexibel automation

Svensson, Andreas January 2012 (has links)
In order to quickly adapt the production on a production line to the demand, there is a needfor flexibility. A tool designed for this purpose, p-sop, has been developed at UniversityWest. This thesis deals with implementation of p-sop in a demonstrator, and developmentof a framework for priority policies as well as a graphical user interface to p-sop. The prioritypolicies evaluated in the demonstrator did note give an increased efficiency, and thegraphical user interface is shown to be well suited for the demonstrator and p-sop in general.
4

3D System-On-Package (SoP) Signal Generator to Control MEMS Movable Microelectrode Arrays

January 2012 (has links)
abstract: Microelectrodes have been used as the neural interface to record brain's neural activities. Most of these electrodes are fixed positioned. Neural signal normally degrades over time due to the body immune response and brain micromotion that move the neurons away from the microelectrode. MEMS technology under SUMMiT VTM processes has developed miniaturized version of moveable microelectrodes that have the ability to recover the neural signal degradation by searching new cluster of neurons. To move the MEMS microelectrode a combination of four voltage waveforms must be applied to four thermally actuated microactuators. Previous design has used OmneticTM interconnect to transfer the waveforms from the external signal generators to the MEMS device. Unfortunately, the mechanism to attach and detach the OmneticTM interconnect introduce mechanical stress into the brain tissue that often caused raptures in the blood vessel. The goal of this project is to create an integrated System-On-Package Signal Generator that can be implanted on the brain of a rodent. A wireless system and a microcontroller are integrated together with the signal generators. The integrated system can be used to generate a series of voltage waveforms that can be customized to drive an array of MEMS movable microelectrodes when a triggered signal is received wirelessly. 3D stacking technique has been used to develop this Integrated System. 3D stacks lead to several favorable factors, such as (a) reduction in the power consumption of the system, (b) reduction in the overall form-factor of the package, and (c) significant reduction the weight of the package. There are a few challenges that must be overcome in this project, such as a commercially available microcontroller normally have an output voltage of 3.3 V to 5.5 V; however, a voltage of 7 - 8V is required to move the MEMS movable microelectrodes. To acquire higher density neural recording, more number of microelectrodes are needed. In this project, SoP Signal Generator is design to drive independently 3 moveable microelectrodes. Therefore, 12 voltage waveform are required. . However, the use of 12 signal generators is not a workable option since the system will be significantly large. This brings us to the other challenge, the limiting size of the rodent brain. Due to this factor, the SoP Signal Generator has to be deisgned to be able to fit without causing much pressure to the rodent's brain. For the first challenge, which is the limited output voltage of 3.3V on the microcontroller, the RC555 timers are used as an amplifier in addition to generating the signals. Demultiplexers have been for the next challenge, which is the need of 24 waveforms to drive 3 electrodes. For each waveform, 1 demultiplexer is used, making a total of 4 demultiplexers used in the entire system, which is a significant improvement from using 12 signal generators. The last challenge can be approached using 3D system stacking technique as mentioned above. The research aims of this project can be described as follows: (1) the testing and realization of the system part, and the designing of the system in a PCB level, (2) implementing and testing the SoP Signal Generator with the MEMS movable microelectrodes, The final outcome of this project can be used not only for neural applications, but also for more general applications that requires customized signal generations and wireless data transmission. / Dissertation/Thesis / M.S. Electrical Engineering 2012
5

Miniaturized and Ferrite Based Tunable Bandpass Filters in LCP and LTCC Technologies for SoP Applications

Arabi, Eyad A. 04 1900 (has links)
Wireless systems with emerging applications are leaning towards small size, light-weight and low cost. Another trend for these wireless devices is that new applications and functionalities are being added without increasing the size of the device. To accomplish this, individual components must be miniaturized and the system should be designed to maximize the integration of the individual components. The high level of 3D integration feasible in system on package design (SoP) concept can fulfill the latter requirement. Bandpass filters are important components on all wireless systems to reject the unwanted signals and reduce interference. Being mostly implemented with passive and distributed components, bandpass filters take considerable space in a wireless system. Moreover, with emerging bands and multiple applications encompassed in a single device, many bandpass filters are required. The miniaturization related to bandpass filters can be approached by three main ways: (1) at the component level through the miniaturization of individual bandpass filters, (2) at the system level through the use of tunable filters to reduce the overall number of filters, and (3) at the system level through the high level of integration in a 3D SoP platform. In this work we have focused on all three aspects of miniaturization of band pass filters mentioned above. In the first part of this work, a low frequency (1.5 GHz global positioning system (GPS) band) filter implemented through 3D lumped components in two leading SoP technologies, namely low temperature co-fired ceramic (LTCC) and the liquid crystal polymers (LCP) is demonstrated. The miniaturized filter is based on a second order topology, which has been modified to improve the selectivity and out-of-band rejection without increasing the size. Moreover, for the case of LCP, the filter is realized in an ultra-thin stack up comprising four metallization layers with an overall thickness of only 100 _m. Due to its ultra-thin structure, the LCP filter is ten times smaller size as compared to the filters reported in published work. The filter is exible and, therefore, suitable for conformal applications. In the second part of this work, relatively higher frequency (Ku band) distributed bandpass filter is presented which can be tuned through an applied magnetic field. This has been realized in a relatively new LTCC tape with magnetic properties, known as ferrite LTCC. Traditionally, magnetically tunable filters require large external electromagnets or coils, which are non-integrable to typical planar circuit boards and are also inefficient. To demonstrate high level of integration, completely embedded windings realized in multiple layers of LTCC have been used instead of the external coils. As a result, the presented bandpass filter is several orders of magnitude smaller that the reported ones. Aside from reducing the size, the embedded windings based design is more efficient than the external coils because it can avoid the demagnetization effect (fields lost at air-ferrite interface) and thus require much smaller bias fields for tunability. Though the embedded windings bring in a number of advantages as mentioned above, the currents passing through these windings generate considerable heat which can inuence the performance of the microwave structure (bandpass filters in our case). This has never been studied before fro Ferrite LTCC based designs with embedded windings. In this work, the effect of the heat generated by these windings has been investigated. It has been found that this self-heating effect inuences the tunability of the filters considerably so it must be estimated at the design stage. Therefore, a strategy to simulate this effect has been developed. The resultant simulations agree well with the measurements verifying the simulation strategy. The designs presented in this work demonstrate the feasibility of realizing highly integrated, miniaturized and tunable filters in SoP platform which are very suitable for modern and futuristic small form factor and slim wireless devices.
6

Modeling, design, fabrication and characterization of miniaturized passives and integrated EM shields in 3D RF packages

Sitaraman, Srikrishna 07 January 2016 (has links)
An innovative structure for thin-film band-pass filters was proposed and analyzed. This structure was employed in the design, fabrication, and development of 3D IPD diplexers on glass substrates with double-side metallization electrically connected by through-vias. Through modeling, design, fabrication and characterization of the WLAN 3D IPD glass diplexers, the proposed filter structure was shown to enable miniaturized and high-performance RF passives. Further, component-level shield structures were developed to provide electromagnetic interference isolation between thin-film passives that are placed less than 100 µm apart. Glass substrates were designed, fabricated and characterized to demonstrate the shield effectiveness of metallized trench and via-array-based shields. The integration of such shields in miniaturized WLAN RF modules enables up to 60dB EM isolation in the frequency range of 1- 20GHz. Advanced RF module technologies based on 3D IPAC concept were designed and demonstrated with ultra-thin low-loss organic and glass substrates, integrating the proposed WLAN actives with miniaturized diplexer and EM shields. Double-side integration of such high-performance components on ultra-thin glass substrates enables up to 8x volume miniaturization including more than 3x reduction in area. Thus, the advanced components demonstrated in this research, vis-a-vis miniaturized diplexers and component-level EMI shields; integrated with actives in ultra-thin glass substrates using the 3D IPAC concept, can enable highly-miniaturized smart systems with multiband wireless communication capabilities.
7

STANDARD OPERATING PROCEDURES FOR THE TRAFFIC INVENTORY DEPARTMENT OF THE DISNEY ABC TELEVISION GROUP

Johnson, Matthew L 01 December 2015 (has links)
The Mack truck principle is the reason a Standard Operating Procedure (SOP) document is a good idea – so I was told by my boss in my early days working for Disney ABC Television Group. This principle is quite simple: if the one person who knows how to do the job walks out the door and is hit by a Mack truck, we have a problem; no one else knows how to do what that person did. And when it comes to television operations, that is a huge dilemma! Standard Operating Procedures is a document that lists the step-by-step process for completing tasks in order to, in this case, keep a network on the air. This document would be beneficial in cases of disaster recovery, but it might be just as useful for training new employees or for covering for someone who is out sick. There may be various reasons to go to the SOP, but they all have the same goal: to keep operations working to fulfill the business objective. An SOP for the operations of an entire network would likely fill at least one if not multiple books, so in order to keep this project manageable, I limited the development of the SOP to one department, Traffic Inventory, which is responsible for the commercial and promotional assets which are sold and scheduled to air on any of the Disney cable networks (Disney Channel, DisneyXD, and Disney Junior.) In order to develop an SOP, it was necessary to review the different software programs in use, and understand their purpose and application to the overall operations of the cable networks. This will be a “living” document, meaning updates and changes will be anticipated, requiring constant maintenance of the SOP in order to keep it up to the latest development. In an effort to make it truly useful, multiple screen captures are used, as this provides a more user-friendly tutorial and makes for a more effective “blueprint” to comprehend and follow. By having Standard Operating Procedures on hand, anyone in the department will be able to effectively follow the process for handling the commercial and promotional assets in an efficient manner, with minimal impact on the daily operation of the networks. This will then be a valuable document, helping the business to keep its commitment to both advertisers and viewers, without the fear of Mack trucks.
8

Design, Modeling, and Optimization of Compact Broadband and Multiband 3D System-On-Package (SOP) Antenna Architectures for Wireless Communications and Millimeter-Wave Applications

DeJean, Gerald Reuben 31 January 2007 (has links)
In recent years, the miniaturization of cell phones and computers has led to a requirement for antennas to be small and lightweight. Antennas, desired to operate in the WLAN frequency range, often possess physical sizes that are too large for integration with radio-frequency (RF) devices. When integrating antennas into three-dimensional (3D) system-on-package (SOP) transceivers, the maintenance of a compact size also provides isolation from other devices, hence, surface wave propagation or high dielectric constant materials such as low temperature cofired ceramics (LTCC) does not affect nearby components of the transceiver such as filters, baluns, and other embedded passives. Therefore, the application of design methods is necessary for realizing compact antennas in the wireless community that can be integrated to RF packages. Furthermore, it is essential that these compact antennas maintain acceptable performance characteristics, such as impedance bandwidth, low cross-polarization, and high efficiency. In addition, the analysis of circuit modeling techniques that could be used to obtain a better understanding of the physical phenomena of the antenna is quite necessary as modules become more and more complex. Based on these requirements, the focus of this research is to improve the design of compact antennas for wireless communications, wireless local area networks (WLAN), and millimeter-wave applications by using time-domain electromagnetic and circuit modeling techniques and optimizations. These compact antenna designs are applied to practical wireless communications systems such as global system of mobile communications (GSM), Bluetooth Industrial-Scientific-Medical (ISM) devices, IEEE802.11a WLAN, and Local Multipoint Distribution Systems (LMDS) applications. Parametric analyses are conducted to study critical parameters that may affect the antenna designs. Moreover, optimizations are performed to optimize the structures, and measured results are presented to validate design techniques.
9

LTCC Fresnel Lens Designs For 24 GHz SoP Automotive Radar Applications

Khalid, Muhammad Umair 12 1900 (has links)
In this thesis, a novel System-on-Package (SoP) antenna concept has been developed for 24 GHz automotive radar applications. High-performance applications such as automotive radars require miniaturization, excellent performance and a high level of integration. The multi-layer Low-temperature co-fired ceramic (LTCC) SOP approach is an effective solution to meet these stringent needs as it offers not only great capability of integrating embedded functions, but also the real estate efficiency and cost-savings. The antenna concept utilizes a mixed LTCC tape system and combines for the first time a fractal antenna array and an integrated grooved Fresnel lens. The overall gain of the system is 15 dB which includes a 6 dB gain enhancement due to the integration of the lens. The bandwidth is 1.8 GHz which is 7.5% of the center frequency. The three types of dielectric Fresnel lenses (grooved, multi-dielectric and perforated) have been investigated as gain enhancement and beam shaping components for high performance LTCC SoP applications. A high dielectric constant material has been utilized to realize the lenses in the LTCC medium. All three lenses perform well with significant gain enhancement (>6 dB) and beam shaping despite their compact sizes (2.4 cm x 2.4 cm). The excellent performance makes all three lenses highly suitable for high performance SoP applications with the grooved lens being most suitable due to the relative ease of fabrication.
10

System on Package (SoP) Millimeter Wave Filters for 5G Applications

Showail, Jameel 05 1900 (has links)
Bandpass filters are an essential component of wireless communication systems that only transmits frequencies corresponding to the communication band and rejects all other frequencies. As the deployment of 5G draws nearer, first deployments are expected in 2020 [1], the need for viable filters at the new frequency bands becomes more imminent. Size and performance are two critical considerations for a filter that will be used in emerging mobile communication applications. The high frequency of 5G communication, 28 GHz as opposed to sub 6 GHz for nearly all previous communication protocols, means that previously utilized lumped component based solutions cannot be implemented since they are ill-suited for mm-wave applications. The focus of this work is the miniaturization of a high-performance filter. The Substrate Integrated Waveguide (SIW) is a high performance and promising structure and Low Temperature Co-Fired Ceramic (LTCC) is a high-performance material that both can operate at higher frequencies than the technologies used for previous telecommunication generations. To miniaturize the structure, a compact folded four-cavity SIW filter is designed, implemented and tested. The feeding structure is integrated into the filter to exploit the System on Package (SoP) attributes of LTCC and further reduce the total area of the filter individually and holistically when looking at the final integrated system. Two unique three dimensional (3D) integrated SoP LTCC two-stage SIW single cavity filters and one unique four-cavity filter all with embedded planar resonators are designed, fabricated and tested. The embedded resonators create a two-stage effect in a single cavity filter. The better single cavity design provides a 15% fractional bandwidth at a center frequency of 28.12 GHz, and with an insertion loss of -0.53 dB. The fabricated four-cavity filter has a 3-dB bandwidth of .98GHz centered at 27.465 GHz, and with an insertion loss of -2.66 dB. The designs presented highlight some of the previously leveraged advantages of SoP designs while also including additions of embedded planar resonators to feed the SIW cavity. The integration of both elements realizes a compact and high-performance filter that is well suited for future mm-wave applications including 5G.

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