This research work focuses on the mechanism of 1/f noise in GaAs
resistors on semi-insulating substrates and 1/f noise due to temperature
fluctuations in heat conduction in resistors, diodes, and bipolar transistors. The
goal of this research is to generate accurate models to explain physical origin of 1/f
noise in...
A radix-based calibration technique was previously proposed with a two-stage algorithmic analog-to-digital converter (ADC). The objective of this work is to verify the capability of radix-based calibration for a true multi-stage ADC. In order to prove the idea, a single bit-per-stage, 20-stage pipelined ADC is designed in a 0.35-μm CMOS...
The passive charge compensation (PCC) technique was introduced for switched capacitor (SC) circuit to increase the slew rate and enhance the linearity performance, as PCC techniques are used on the Delta-Sigma modulator (DSM) in ADC circuitry. The PCC technique of the project was applied to the design of a SC...
As screen resolution and video decoding capability have increased, high-definition (HD) video in resolutions as high as 1920 x 1080 is rapidly becoming the standard. Ad-hoc streaming of HD video over 802.11 wireless networks, e.g., streaming from a mobile device to a television, is convenient for users, but is hampered...
Ring amplification has emerged as an efficient technique to drive large capacitive loads in switched capacitor circuits. We propose circuit techniques to demonstrate the first application of a ring amplifier in a non-capacitive feedback system of a LDO. These techniques enable a simple cap-less LDO structure in 180nm CMOS that...
Dynamic DC offset is one of the biggest problems preventing the implementation of single chip receivers. This thesis presents a 2.4GHz downconversion mixer designed to work with adaptive DC offset cancellation for a fully integrated direct conversion receiver. Offset can be removed by dynamically changing the PFET load bias in...
The increasing demand for higher data-rates is challenging to satisfy with spectrum-deficient indoor WiFi networks. A novel hybrid WiFi Free-Space Optical (WIFO) system has been proposed to enhance the wireless capacity of indoor WiFi networks. In this thesis, an integrated optical wireless receiver is designed and integrated in 65-nm CMOS...
The ability to accurately locate people and objects indoors will enable opportunities for control and automation of indoor environments. Current indoor localization solutions require dedicated hardware which must be custom tailored to each application. There are large technological, societal, and economic benefits in developing a more general purpose system that...
The sensors in real time data processing IoT devices require high resolution and sub-MHz data converters, usually implemented as Incremental ADCs due to the advantages of oversampling technique and low latency. In discrete time incremental (IDT) ADCs, the sampling switch non-linearity, charge injection degrade the resolution, and power hungry OPAMPs...
In cellular telephones, RF power amplifiers consume a significant part of the total phone current. Reducing the average PA current will extend battery life. In GSM systems the handset is commanded by the base station to transmit at power levels lower than full power much of the time. A Doherty...
In this thesis, we propose a Blockchain-based distributed protocol for enabling deployment of dynamic, on-demand IoT networks. Specifically, the proposed protocol leverages Blockchain technology to: (i) enable distributed and secure authentication, registration, and management of IoT devices; (ii) provide fast discovery of IoT resources and scalable and secure instantiation of...
A modeling technique for simulating the noise
performance of chopper-stabilized switched-capacitor
filters using SPICE2 is presented. A method for
selection of switched-capacitor network (SCN) stages
to be chopped and an op amp topology for low noise
applications are also outlined. Validity of the
modeling is verified by the close agreement...
Various natural language processing (NLP) tasks necessitate deep models that are fast, efficient, and small based on their ultimate application at the edge or elsewhere. While significant investigation has furthered the efficiency and reduced the size of these models, reducing their downstream latency without significant trade-offs remains a difficult task....
This thesis presents a channelized digital receiver design for UWB sytems in a multipath indoor environment. The UWB technology has been used for commercial and military purposes due to a number of advantages such as low-power consumption, noise-like and carrier free. The energy of UWB signal is spread over a...
The chopper-stabilized operational amplifier has good low
frequency noise properties. Unfortunately a simple technique for
simulation of the chopper-stabilized operational amplifier has
not been available.
This thesis describes the implementation of a differential
amplifier using chopper stabilization and its circuit modeling
for the SPICE simulation. This circuit has been designed...
A short-circuit-protected line-driver circuit is
particularly adapted for use in a CMOS differential line-driver
system, where one line-driver circuit provides a
true output signal, and another line-driver circuit
provides a complementary false output signal. A short-circuit
is sensed by measuring current through a secondary
pull-up transistor, and disabling a primary...
Various applications like wireless UWB communication, fast data acquisition systems and digital storage oscilloscopes needs ADCs with instantaneous input signal bandwidth from 0.1-40 GigaHertz range with 6-10 bits of resolution -- a challenging task and an impressive goal to achieve. Flash ADCs have been conventionally employed to achieve these goals...
AES (Advanced Encryption Standard), also known as Rijndael, is a symmetric key block cipher adopted as an encryption standard by the US government and used extensively in cryptographic applications worldwide. ARM is the most popular processor core used in embedded applications. This thesis surveys the available public implementations of AES...
Recently, continuous-time ΔΣ modulators are appearing increasingly often in both the literature and the marketplace due to their features of inherent antialiasing and relaxed requirements for opamp and so on. However, several nonideal factors such as clock jitter, excess loop delay, inter-symbol interference and so on, degrade the SNR performance...
The harmonic problem in power systems is gaining more attention as incidences correlated with harmonics increase. Conventional passive filtering techniques for harmonic mitigation have inherent problems, and purely active filters have the disadvantages of higher costs and ratings. Hybrid active filters inherit the efficiency of passive filters and the improved...
An analysis of substrate noise coupling in mixed-signal circuits has been performed in the TSMC 0.25 [mu]m lightly doped and heavily doped CMOS processes. Methods to minimize noise coupling in both the chip design and board design phases are presented along with techniques for accurate circuit simulation of noise coupling....
Three types of low noise amplifiers operating at 2.4GHz were designed. They are the commonly used single-ended and differential amplifiers as well as a new quasi-differential amplifier. The substrate noise injected into these amplifiers is examined for both heavily and lightly doped CMOS substrates. For the single-ended amplifier the noise...
For many years, the von Neumann bottleneck has imposed speed limits on the execution of a program. Because of their sequential nature, von Neumann computers can only execute a single instruction at a time. Instructions that are side-effect free and can be executed in parallel must wait. In an effort...
A comparison of two novel demodulators. The first is a basic zero crossing demodulator,
as introduced by Beards. The second is an approach proposed by Hovin. The two demodulators
are compared to each other and to the conventional method of demodulation.
Retention of engineering students is a problem for many universities, especially during the first year. The problem of introducing students to engineering while increasing retention rates has recently been addressed by many different universities. Implementing novel lab structures, adjusting the lecture to incorporate more effective teaching techniques, and using orientation...
A new, computer oriented system for automatic, in situ
monitoring of water quality is proposed which makes full and effective
use of modern computer technology. The main objective of this thesis
work was the development of the concept for in situ computer controlled
experimenting as a reasonable and effective means...
The dynamics of land use in the State of Oregon are simulated
on a digital computer. The introductory chapter outlines the complex
nature of the problems facing the post-industrial society and argues
that the scientific and professional estates share in the responsibility
for public policy formulation. The second chapter .presents...
This thesis presents a continuous time bandpass delta sigma modulator with frequency translation inside the delta sigma loop. The input IF signal is down converted to baseband after amplification by a low Q, wideband bandpass resonator. The down converted IF signal is digitized by a continuous time, second order lowpass...
Amateur Packet Radio Networking presently uses the NET/ROM
protocol to establish the network. NET/ROM is considered to be
insufficient to support the expected growth of the network. This
research work proposes to use the TCP/IP protocol suite instead to
build the network. A comparison between features of both protocols
supports...
Decision Feedback Equalization (DFE) in a data recovery channel filters
the bit decision in the current symbol period in generating the sample at the
comparator in the subsequent clock period. The operations of sampling,
comparing, filtering the decision bits into a feedback signal, and subtraction of
that feedback signal are...
This thesis presents a low power DC-DC converter suitable for harvesting energy from high impedance thermoelectric generators (TEGs) for the use in body powered electronics. The chip has been fabricated in a 130nm CMOS technology. To meet the power demands of body powered networks, a novel dual-path architecture capable of...
Pulse Width Modulation (PWM) has been used extensively for motor control, DC-AC
converters, DC-DC converters and in audio applications. The conventional method of
generating a pulse width modulated signal involves generating an accurate sawtooth or triangle
wave using analog circuits. In CMOS, being analog circuit intensive puts extra constraints
on...
As Moore’s Law continues to give rise to ever shrinking channel lengths, circuits are becoming more digital and ever increasingly faster. Generating high frequency clocks in such scaled processes is becoming a tough challenge. Digital phase locked loops (DPLLs) are being explored as an alternative to conventional analog PLLs but...
We present a new circuit design for adaptive offset cancellation in a fully differential 2.4 GHz CMOS direct conversion mixer. Our circuit structure is a modification of a Gilbert cell mixer in which offsets are cancelled by injecting cancellation currents into the legs of the mixer by dynamically varying the...
Commonly proposed ocean wave energy converters (OWEC) use inefficient and maintenance demanding intermediate hydraulic and pneumatic systems. We propose a novel rotary direct-drive OWEC that eliminates these intermediate stages. The new device employs a contactless force transmission system (CFTS) comprising a “piston” and a “cylinder” and a ball screw to...
FISHNET (Facilities Integrated in a Shared Habitat) is a communication subnet architecture utilizing a hybrid application of point-topoint and broadcast communications to achieve a high degree of network performance. This objective is achieved through utilizing a dual bus structure: a data bus and a control bus. The data bus consists...
With the development of high performance power electronic and semiconductor technologies, Adjustable Speed Drive (ASD) systems are increasingly applied in residential, commercial and industrial applications. Due to the advantages at higher power ratings, the three-level Neutral-Point-Clamped (NPC) Voltage Source Inverter (VSI) is being employed in industrial and traction applications, static...
Power quality has become an important concern to both electric utilities and
end users due to the increased use of non-linear loads in modem power systems
over the past decade. Nonlinear loads inject harmonics into the power system and
thus may lead to poor power quality and lower power factor....
This dissertation presents a dual-path 2-0 MASH (Multi-stAge-noise -SHaping) ADC with two verified digital corrections of DAC mismatch error and quantization noise leakage. By using these two techniques, the requirements for the analog circuits are greatly relaxed. The dual-path structure generates two outputs, one only composed of conversion errors, the...
It is popular belief that the volatility of the exchange rate is due
to the balance of payments, which in turn is mainly influenced by the
balance of trade. A closed-loop dynamic economic model is proposed
to describe and analyse the effect of the international trade of a
country on...
An adaptive decentralized nonlinear controller for a robot manipulator
is presented in this thesis. Based on the adaptive control schemes designed
by Seraji [18], Dai [30], and Jimenez [31], we redesigned and further
simplified the control algorithm and, as a consequence, we achieved better
path tracking performance.
The proposed adaptive...
A fast-settling CMOS operational amplifier using the
folded-cascode topology has been designed. The design is
based on a theory developed by Yang et al for the optimum
settling time of two-pole systems for switched-capacitor
applications. The theory states that the two poles are
separated by a given factor in order...
Researchers at Oregon State University, focusing on the development of ocean wave energy converters, have designed and installed a unique linear test bed to aid in the characterization of these converters. Under the original control scheme, the linear test bed follows a position profile and is limited in its ability...
Wave energy converter (WEC) devices are complicated systems containing hydrodynamic, mechanical, and electrical elements. WEC design efforts are primarily focused in the time-domain, using frequency-based energy analyses and numerical problem solving approaches that are staples in hydrodynamic design efforts to form the basic information set used in these time-domain development...
This thesis proposes a novel fully digital technique for the estimation and correction of the DAC error in multi-bit delta sigma ADCs. The structure of the DAC error is indicated through a simple model for unit-element based DACs. The impact of the DAC error on the performance of ADC is...
In any biomedical signal acquisition system, a front-end amplifier is needed to amplify low amplitude bio-signals while filtering out any unwanted low-frequency artifacts. The design of low frequency poles within the sub-Hz range implies very large time-constants which goes against system integrability. In recent years, the pseudo resistor has been...
This document investigates, justifies, designs, and simulates the application of a fuzzy logic controller/optimizer in a sawmill bucking system application that is the first production station where stems coming from the mountains are processed in a sawmill. One of the areas of success in the application of fuzzy logic is...
The electrical grid is a key component of the Nation's critical infrastructure. Its continuous and reliable operation is of vital importance; any system-wide disruption would have a debilitating impact on crucial services, public health and safety, the economy, and the national security of the United States.
High-impact low-frequency events pose...