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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.
111

VLSI Implementation of Digital Signal Processing Algorithms for MIMO/SISO Systems

Shabany, Mahdi 30 July 2009 (has links)
The efficient high-throughput VLSI implementation of near-optimal multiple-input multiple-output (MIMO) detectors for 4x4 MIMO systems in high-order quadrature amplitude modulation (QAM) schemes has been a major challenge in the literature. To address this challenge, this thesis introduces a novel scalable pipelined VLSI architecture for a 4x4 64-QAM MIMO receiver based on K-Best lattice decoders. The key contribution is a means of expanding/visiting the intermediate nodes of the search tree on-demand, rather than exhaustively along with three types of distributed sorters operating in a pipelined structure. The combined expansion and sorting cores are able to find the K best candidates in K clock cycles. The proposed architecture has a fixed critical path independent of the constellation order, on-demand expansion scheme, efficient distributed sorters, and is scalable to a higher number of antennas/constellation orders. Fabricated in 0.13um CMOS, it operates at a significantly higher throughput (5.8x better) than currently reported schemes and occupies 0.95 mm2 core area. Operating at 282 MHz clock frequency, it dissipates 135 mW at 1.3 V supply with no performance loss. It achieves an SNR-independent decoding throughput of 675 Mbps satisfying the requirements of IEEE 802.16m and Long Term Evolution (LTE) systems. The measurements confirm that this design consumes 3.0x less energy/bit compared to the previous best design.
112

Enabling active locomotion and advanced features in capsule endoscopy

Alonso Casanovas, Oscar 27 April 2012 (has links)
The significant development in medical diagnostics and imaging has brought up a lot of new wireless capsule endoscopes coming to health care market. The capsule has been able to minimize patient discomfort and pain during digestive tract screening with less risk of infection and harmless to body organs. This kind of medical procedure is less invasive and gives a great impact compared to the traditional method. Although pill-shaped capsules have existed for over 11 years by now and are currently being used successfully in medical screening to study the GI tract, these systems are passive and are dependent to the peristaltic movement of the gastric wall to propel. The aim of this work is to provide the electronics needed to control an endoscopic capsule robot and the electronics needed to enable active locomotion and advanced vision functions (like autofocus). Enabling such functions the capsules will be able to perform screening, diagnosis and therapy. Such capsule robot has been designed in the framework of the “Versatile Endoscopic Capsule for Gastrointestinal Tumour Recognition and Therapy” (VECTOR) project. This project pursues the goal of realizing smart pill technologies and applications for gastrointestinal (GI) diagnosis and therapy. The overall medical goal of the project is to enable medical devices through advanced technology that can dramatically improve early detection and treatment of GI early cancers and cancer precursors. The main technological objective of the project is the take-up of microsystems and sub-components and their integration into robotic, mobile pill devices for useful and large impact applications in the medical field.
113

Implementation of an Active Pixel Sensor with Shutter and Analog Summing in a 0.35um Process / Implementation av en ljussensor med aktiva pixlar, elektronisk slutare och analogsummering i en 0.35um process.

Johansson, Robert January 2003 (has links)
An integrated circuit for evaluation of APS technology has been implemented in a 0.35 um process. The APS features snapshot operation and the readout circuitry can carry out: CDS, DS, and analog summing all in one circuit that is fully programmable. The output from the chip is a differential analog signal, intended to be connected to a high-speed ADC on an evaluation board. The sensor is fully compatible with current IVP camera systems, hence, the evaluation board should be easy to design. Several small code snippets that illustrate different modes of readout have been outlined, to aid the evaluation of the chip. It should be fairly straightforward to convert these code snippetsinto actual camera code. Furthermore, some code to illustrate a possible application and a faster mode of CDS have been indicated. Six types of APs have been implemented. They differ regarding diode type and implementation of the sampling capacitor. Design instructions and models for hand calculation have been described. The models have in most cases been validated by simulations and it has been shown that a readout speed of 8 MHz is possible to obtain, even for a larger sensor than this test chip. The desired resolution of 8 bits cannot be obtained for high levels of illumination. However, for low levels of illumination a resolution as high as 10 bits is possible. The chip layout has been validated to a large extent and should result in a fully functional chip, if manufactured. However, in the eventuality that IVP decides to manufacture this chip it is recommended to use the newer CAD tools, not available to the author at the time of implementation, to check the chip design for DRC and LVS errors.
114

Implementering av ett parameteriserbart aktivt vågfilter / Implementation of a parameterized wave active filter

Gustafsson, Helena January 2003 (has links)
Detta examensarbete gick ut på att försöka hitta ett sätt att mäta kompo nentkänslighet hos parameteriserbara aktiva vågfilter. Två olika ansatser har gjorts, men bara ett försök har avslutats. Det första försöket behandlar möjligheten att realisera ett vågfilter med hjälp av standardkomponenter i en kretskortslösning. Detta fungerade inte beroende på att nödvändiga komponenter inte finns på marknaden idag. Komponenterna som finns har för stora parasitkapacitanser. Dessa oönskade parasiter var så stora att de skulle kunna förstöra funktionen och det var således inte värt att fortsätta försöket. De komponenter som undersöktes var resistansstegar och digitala potentiometrar. Den största delen av studierna till det första försöket har bestått i att studera datablad från olika kretstillverkare för att hitta lämpliga komponenter. Istället startades ett nytt försök som syftade till att undersöka möjligheten att implementera ett aktivt vågfilter i en integrerad krets. I denna rapport presenteras en förstudie till hur en sådan lösning skulle kunna se ut. För att möjliggöra en fortsättning där mitt examensarbete tar slut har arbetet förklarats ingående. Jag har också inkluderat min programkod som bilagor i slutet av rapporten. / The purpose of this thesis was to find a way of measuring the sensitivity of component values for parameterized wave active filters. Two different approaches were made, but only one was finished. The first approach is about the possibility of making a wave active filter with standard components on a printed circuit board. This did not work though, because of a scarce market of possible components. The compo-nents existing today have too high parasite capacitances. These unwanted parasites are so large in value that they could destroy the functionality and it was therefore not worth continuing the attempt. The components that were investigated as possible on the board were ladder networks and digitally controlled potentiometers. The main part of the studies for the first attempt was to read data sheets from different electronic companies trying to find possible components. Instead a new approach was made with the purpose of investigating the possibility of making a wave active filter as an integrated circuit. In this report a pilot study for such an attempt is presented. To make it possible to continue work where these studies end, the work has been carefully explained. I have also included the computer programs I have made in the appendix of the report.
115

Inverse Discrete Cosine Transform by Bit Parallel Implementation and Power Comparision

Bhardwaj, Divya Anshu January 2003 (has links)
The goal of this project was to implement and compare Invere Discrete Cosine Transform using three methods i.e. by bit parallel, digit serial and bit serial. This application describes a one dimensional Discrete Cosine Transform by bit prallel method and has been implemented by 0.35 ìm technology. When implementing a design, there are several considerations like word length etc. were taken into account. The code was implemented using WHDL and some of the calculations were done in MATLAB. The VHDL code was the synthesized using Design Analyzer of Synopsis; power was calculated and the results were compared.
116

Physical Planning of ASIC’s in mobile systems

Roos, Håkan January 2007 (has links)
With increasing demands in terms of timing, area and power, today’s ASIC (Application Specific Integrated Circuit) designers are faced with new problems as technology emerges. Ericsson has started to work in 65 nm and realized that the methods used in previous, larger technologies, does not offer good enough correlation between synthesis and the results after physical placement. This leads to several expensive and time consuming iterations back and forth between Ericsson and the ASIC vendor. In order to narrow the gap between Ericsson and the ASIC vendor, and hence increase correlation, physical planning has been identified as a possible solution. Cadence First Encounter, part of the Cadence Encounter digital IC design platform, is an advanced tool for silicon virtual prototyping. The tool basically brings back-end placement knowledge to front-end ASIC designers. This master’s thesis main goal is to evaluate Cadence First Encounter and investigate how it could be integrated with Ericsson’s design flow. The tool has been tested on previous designs with known issues and the results are positive. By using the prototype work flow in First Encounter that is described in this report, it is possible to identify and correct issues with the netlists in time, which will help shortening the lead time in projects and hence also the time to market.
117

Design of Hybrid CMOS/Pass-Transistor-Logic Standard Cell Library

Tsai, Cheng-Hsuan 30 August 2010 (has links)
The mainstream of current VLSI design and logic synthesis is based on traditional CMOS logic circuits. However, various new logic circuit design styles based on pass-transistor logic (PTL) have been proposed. The advantage of PTL is higher speed, smaller area and lower power for some particular circuits such as XOR. Since most current automatic logic synthesis tools (such as Synopsys Design Compiler) are based on conventional CMOS standard cell library, the corresponding logic minimization for CMOS logic cannot be directly employed to generate efficient PTL circuits. In this thesis, we develop a novel PTL synthesizer that can efficiently generate PTL-based circuits. We proposed a new synthesis method (hybrid PTL/CMOS Library design) that has multiple driving strengths and multiple threshold voltages to achieve better performance in area, speed, and power. Since PTL-based circuits are constructed by only a few basic PTL cells, the layouts in PTL cells can be easily updated as the process technology migrates rapidly in current Nano technology era. The proposed PTL logic synthesis flow employs the popular Synopsys Design Compiler (DC) to perform logic translation and minimization based on the standard cell library composed of PTL and CMOS logic cells. Thus, the PTL design flow can be easily embedded in the standard cell-based ASIC design flow.
118

Measuring and Navigating the Gap Between FPGAs and ASICs

Kuon, Ian 08 March 2011 (has links)
Field-programmable gate arrays (FPGAs) have enjoyed increasing use due to their low non-recurring engineering (NRE) costs and their straightforward implementation process. However, it is recognized that they have higher per unit costs, poorer performance and increased power consumption compared to custom alternatives, such as application specific integrated circuits (ASICs). This thesis investigates the extent of this gap and it examines the trade-offs that can be made to narrow it. The gap between 90 nm FPGAs and ASICs was measured for many benchmark circuits. For circuits that only make use of general-purpose combinational logic and flipflops, the FPGA-based implementation requires 35 times more area on average than an equivalent ASIC. Modern FPGAs also contain "hard" specific-purpose circuits such as multipliers and memories and these blocks are found to narrow the average gap to 18 for our benchmarks or, potentially, as low as 4.7 when the hard blocks are heavily used. The FPGA was found to be on average between 3.4 and 4.6 times slower than an ASIC and this gap was not influenced significantly by hard memories and multipliers. The dynamic power consumption is approximately 14 times greater on average on the FPGA than on the ASIC but hard blocks showed promise for reducing this gap. This is one of the most comprehensive analyses of the gap performed to date. The thesis then focuses on exploring the area and delay trade-offs possible through architecture, circuit structure and transistor sizing. These trade-offs can be used to selectively narrow the FPGA to ASIC gap but past explorations have been limited in their scope as transistor sizing was typically performed manually. To address this issue, an automated transistor sizing tool for FPGAs was developed. For a range of FPGA architectures, this tool can produce designs optimized for various design objectives and the quality of these designs is comparable to past manual designs. With this tool, the trade-off possibilities of varying both architecture and transistor-sizing were explored and it was found that there is a wide range of useful trade-offs between area and delay. This range of 2.1 X in delay and 2.0 X in area is larger than was observed in past pure architecture studies. It was found that lookup table (LUT) size was the most useful architectural parameter for enabling these trade-offs.
119

Measuring and Navigating the Gap Between FPGAs and ASICs

Kuon, Ian 08 March 2011 (has links)
Field-programmable gate arrays (FPGAs) have enjoyed increasing use due to their low non-recurring engineering (NRE) costs and their straightforward implementation process. However, it is recognized that they have higher per unit costs, poorer performance and increased power consumption compared to custom alternatives, such as application specific integrated circuits (ASICs). This thesis investigates the extent of this gap and it examines the trade-offs that can be made to narrow it. The gap between 90 nm FPGAs and ASICs was measured for many benchmark circuits. For circuits that only make use of general-purpose combinational logic and flipflops, the FPGA-based implementation requires 35 times more area on average than an equivalent ASIC. Modern FPGAs also contain "hard" specific-purpose circuits such as multipliers and memories and these blocks are found to narrow the average gap to 18 for our benchmarks or, potentially, as low as 4.7 when the hard blocks are heavily used. The FPGA was found to be on average between 3.4 and 4.6 times slower than an ASIC and this gap was not influenced significantly by hard memories and multipliers. The dynamic power consumption is approximately 14 times greater on average on the FPGA than on the ASIC but hard blocks showed promise for reducing this gap. This is one of the most comprehensive analyses of the gap performed to date. The thesis then focuses on exploring the area and delay trade-offs possible through architecture, circuit structure and transistor sizing. These trade-offs can be used to selectively narrow the FPGA to ASIC gap but past explorations have been limited in their scope as transistor sizing was typically performed manually. To address this issue, an automated transistor sizing tool for FPGAs was developed. For a range of FPGA architectures, this tool can produce designs optimized for various design objectives and the quality of these designs is comparable to past manual designs. With this tool, the trade-off possibilities of varying both architecture and transistor-sizing were explored and it was found that there is a wide range of useful trade-offs between area and delay. This range of 2.1 X in delay and 2.0 X in area is larger than was observed in past pure architecture studies. It was found that lookup table (LUT) size was the most useful architectural parameter for enabling these trade-offs.
120

Digital implementation of high speed pulse shaping filters and address based serial peripheral interface design

Rachamadugu, Arun 19 November 2008 (has links)
A method to implement high-speed pulse shaping filters has been discussed. This technique uses a unique look up table based architecture implemented in 90nm CMOS using a standard cell based ASIC flow. This method enables the implementation of pulse shaping filters for multi-giga bit per second data transmission. In this work a raised cosine FIR filter operating at 4 GHz has been designed. Various Implementation issues and solutions encountered during the synthesis and layout stages have been discussed. In the second portion of this work, the design of a unique address based serial peripheral interface (SPI) for initializing, calibrating and controlling various blocks in a large system has been discussed. Some modifications have been made to the standard four-wire SPI protocol to enable high control speeds with lesser number of top-level pads. This interface has been designed to function in the duplex mode to do both read and write operations.

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