The parasitic components of MOS switches at high speeds affect the linearity and resolution of CMOS sample and hold circuits. CCD-based circuit design can offer good performance at high speeds. This thesis presents the design of sample and hold circuits using charge-coupled device structures in a standard CMOS process. Three sample and hold circuits have been built and tested for linearity and speed performance. The CCD S/Hs have been characterized using a continuous-time integrator and a Δ∑ ADC. The CCDs, with a switched capacitor amplifier at the output, achieve an SFDR of 54dB for an input signal V[subscript in]=2.6V+0.4Vpp at f[subscript in]=10.1KHz. / Graduation date: 2003

The general expressions for finding the network functions, e.g., the immittance and the scattering parameters, of a general, uniformly coupled n-line structure in an inhomogeneous medium are derived in terms of the normal mode parameters of the system. These are used to compute or to derive the explicit expressions for the elements of the immittance matrix in terms of normal mode parameters. The scattering parameters of a general non-symmetrical directional coupler with arbitrary terminations are derived in terms of the known scattering parameters with a specified set of terminations such as characteristic non-mode converting terminations. The formulation is quite general and can be applied to various coupled guided wave systems, including coupled microstrip lines, slot lines, comb lines, dielectric waveguides and various other uniformly coupled transmission systems. The results obtained are used to present the procedure to determine the optimum terminations for directional couplers and sensitivity of various multiports, including couplers, to changes in terminations. It is shown that the coupler performance can be optimized in terms of the terminating impedances. The analysis and design procedure for both symmetrical and nonsymmetrical four-port coupled structures consisting of the symmetrical three lines in an inhomogeneous medium such as microstrips are presented. Tables and charts for the design of three-line structure are based on the closed form expressions for the immittance parameters. The analysis and design procedure for open-circuited interdigital multiple coupled microstrip line structures for applications as wideband DC blocks and filters are also presented. As in the case of the other microstrip structures, the initial design is based on the TEM assumption and the final geometry is then determined by the exact computation of the frequency response of the two ports. For larger numbers of lines, the design is based on the equivalent even- and odd-mode parameters of the n-line system. For this case, the TEM design equations, derived in terms of even- and odd-mode impedances of a pair of lines, can be translated into a physical configuration by using published results on coupled lines. / Graduation date: 1983

In modern telecommunications, there is a need for quadrature oscillator exhibiting an accurate and stable phase relation. For example, identical two mutually coupled relaxation oscillator can generate identical quadrature signals, and have extremely accurate and stable phase relation. In this thesis, we propose a current cross-coupled relaxation oscillator with quadrature outputs. The oscillator consists of two identical current relaxation oscillators and a current comparator. The circuit takes the high frequency advantage of current mode circuit. Because of cross-coupled feedback, this oscillator have highly accurate ( <1¢X) and stable quadrature outputs. It is implemented by using TSMC 0.35£gm 2P4M CMOS technology.

The suitable frequency range of electromagnetic interference (EMI) filters is always limited by the parasitic inductances and capacitances of components. The main object in this research is to develop design rules for lowering parasitic effects due to parasitic inductance of capacitor by using three coupled inductors. In this thesis, the properties and equivalent circuit of three coupled inductors are discussed first. It is found that two negative series inductances can be simultaneously obtained at two ports when the parameters of three coupled inductors are appropriately selected. These two negative inductances can be used to lower parasitic effect of capacitors. In other words, the EMI filter performance can be effectively improved by using this technology. Furthermore, method to completely reduce parasitic inductances is derived. The common mode insertion loss of this design is able to achieve at the rate of -60 dB/decade at high-frequency. For differential mode the insertion loss is even higher to the rate of -100 dB/decade.

Real-time wave forecasts are critical to a variety of coastal and offshore opera- tions. NOAA’s global wave forecasts, at present, do not extend into many coastal regions of interest. Even after more than two decades of the historical Exxon Valdez disaster, Cook Inlet (CI) and Prince William Sound (PWS) are regions that suffer from a lack of accurate wave forecast information. This dissertation develops high- resolution integrated wave forecasting schemes for these regions in order to meet the critical requirements associated with shipping, commercial and sport fishing vessel safety, and oil spill response. This dissertation also performs a detailed qualitative and quantitative assessment of the impact of various forcing functions on wave pre- dictions, and develops maps showing extreme variations in significant wave heights (SWHs). For instance, it is found that the SWH could vary by as much as 1 m in the northern CI region in the presence of currents (hence justifying the need for integration of the wave model with a circulation model). Such maps can be useful for several engineering operations, and could also serve as guidance tool as to what can be expected in certain regions. Aside from the system development, the issue of forecast reliability is also addressed for PWS region in the context of the associated uncertainty which confronts the manager of engineering operations or other planners. For this purpose, high-resolution 36-h daily forecasts of SWHs are compared with measurements from buoys and satellites for about a year. The results show that 70% of the peak SWHs in the range 5-8 m were predicted with an accuracy of 15% or less for a forecast lead time of 9 h. On average, results indicate 70% or greater likelihood of the prediction falling within a tolerance of ±(1*RMSE) for all lead times. This analysis could not be performed for CI due to lack of data sources.

The introduction of deep reactive ion etching (DRIE) technology has greatly expanded the accessible design space for microscopic systems. Structures that are hundreds of micrometers tall with aspect ratios of 40:1, heretofore impossible, can now be achieved. However, this technology is primarily a forming technology, sculpting structures from a substrate. This work seeks to complement deep reactive ion etching by developing an electrical isolation technology to enable electro-mechanical function in these new deep reactive ion etched structures. The objective of the research is twofold. The first is to develop and characterize an electrical isolation technology for DRIE, single crystal silicon (SCS) micro-electro-mechanical systems (MEMS) using temperature gradient zone melting (TGZM) of aluminum junctions for diodic isolation. The second is to demonstrate the utility of this electrical isolation technology in the design, simulation, fabrication, and testing of a MEMS device, i.e. a micro-gyroscope, in such a way that the benefits from junction isolated, deep reactive ion etched, single crystal silicon devices are preserved.

In the first part of this dissertation we explore the consequences of high frequency operation of Josephson junction arrays. At high frequencies these systems are no longer well modeled by Kirchhoffs laws, and new dynamical equations are derived directly from Maxwells equations. From these equations we derive a reduced set of averaged equations which greatly simplify the analysis of high frequency arrays. The averaged equations allow us to examine experimental strategies for obtaining higher power outputs from arrays. These strategies rely on resonant architectures that place the junctions near antinodes of a desired standing wave mode of the fluctuating current. Simple, heuristic rules are derived for the proper placement of junctions. The second part of the dissertation is devoted to stochastic resonance. A new theory is proposed to explain both two-state and excitable stochastic resonance. Previous theories explaining the two types of stochastic resonance yield similar results while using different analytic strategies. A constrained asymmetric rate model is derived that in one limit produces the proper result for the two-state system, while in another limit models the excitable system. The result that the constrained asymmetric rate model gives in the excitable limit is off by a factor of two, and this discrepancy is examined. Furthermore, we study the consequences of adding a colored noise source to the classic two-state model of stochastic resonance. We will find that when both white and colored noise sources are present, stochastic resonance will occur as a function of colored noise strength only if the correlation time of the colored noise source is small enough. Two theories are proposed to explain this phenomenon and both are examined in detail.

During the latest ten years, development in the industry of machine tools has been growing rapidly in our country. Since industry automation is highly demanded, the study about CNC is therefore extensively proceeded. Owing to request for higher quality, the machine tool must achieve the high speed and high precision. There are three factors in precise motion control : the accuracy of reference command, the design of servo control structure, and machine structure. However the part of machine structure attains to maturity. The design of the control system need to include good motion control and correct reference command. NURBS can represent analytic curves and free-form curves accurately and easily. Cross-coupled control is able to adjust the dynamic system of each axis to reduce the contour errors. It is expected to improve control performance in terms of contour errors by combine NURBS reference command and the cross-coupled control framework. Keywords¡Gmachine tool, NURBS, cross-coupled control

Using compact structure to improve the defect of traditional transmission line filter which size is too big or transmission line is too long. Two special structures are used to implement the filter that is smaller or superior characteristic. One of the two structures is called DGS that etched defect in the ground plane. The etched lattice shape for the transmission line consists of narrow and wide etched areas in backside metallic ground, which give rise to increasing the effective capacitance and inductance of a transmission line, respectively. Thus, by using this character, the low-pass filters are designed and implemented easily. Another structure is coupled of microstrip square open-loop resonators. First, the coupling coefficients of the three basic coupling structures versus distance between adjacent resonators and different offset is established by means of three-dimensional field analysis methods. Then, the band-pass filter will be implemented by the combination of three basic coupling structures. Finally, two low-pass filter which have cutoff frequency 5.4GHz¡B2.26GHz and a four-pole band-pass filter are designed and fabricated. All theoretical and experimental performance is presented.

Determination of lead and iodine species by capillary electrophoresis inductively coupled plasma mass spectrometry.