Nowadays, Multi-GHz analog-to-digital converters (ADCs) are becoming more and more popular in radar systems, software-defined radio (SDR) and wideband communications, because they can realize much higher operation speed through using many interleaved sub-ADCs to relax ADC sampling rates. Although the time interleaved ADC has some issues such as gain mismatch, offset mismatch and timing skew between each ADC channel, these deterministic errors can be solved by previous works such as digital calibration technique. However, time-interleaved ADCs require a precise sample clock to achieve an acceptable effective-numberof-bits (ENOB) which can be degraded by jitter in the sample clock. The clock generation circuits presented in this work achieves sub-picosecond jitter performance in 180nm CMOS which is suitable for time-interleaved ADC. Two different test chips were fabricated in 180nm CMOS to investigate the low jitter design technique. The low jitter delay line in two chips were designed in two different ways, but both of them utilized the low jitter design technique. In first test chip, the measured RMS jitter is 0.1061ps for each delay stage. The second chip uses the proposed low jitter Delay-Locked Loop can work from 80MHz to 120MHz, which means it can provide the time interleaved ADC with 2.4GHz to 3.6GHz low jitter sample clock, the measured delay stage jitter performance in second test chip is 0.1085ps.

The travel times of public transit systems that operate on mixed use right-of-ways are often dictated by the delays experienced at signalized intersections. When these delays become large and/or highly variable, transit quality degrades and agency operating costs increase. A number of transit priority measures can be applied, including transit signal priority or queue jump lanes. However, it is necessary that a process of prioritizing intersections for priority treatment be conducted so as to ensure the greatest return on investment is achieved. This thesis proposes and demonstrates a methodology to determine the distribution of stopped delays experienced by transit vehicles at signalized intersections using archived AVL (automated vehicle location) and APC (automated passenger counting) data. This methodology is calibrated and validated using queue length and bus unscheduled stopped delay data measured at a field site. Results show the proposed methodology is of sufficient accuracy to be used in practice for prioritizing signalized intersections for priority treatment. On the condition that a sample of the transit vehicle fleet is equipped with an AVL/APC system, the proposed methodology can be automatically implemented using the archived AVL/APC data and therefore avoid the need to conduct dedicated data collection surveys. The proposed methodology can provide estimates of (1) the maximum extent of the queue; and (2) measures of the distribution of stopped delays experienced by transit vehicles (e.g. mean, standard deviation, 90th percentile, etc.) caused by the downstream traffic signal. These measures can be produced separately for different analysis periods (e.g. different times of the day; days of the week; and time of the year) and can be compiled separately for different transit routes. These outputs can then be used to identify and prioritize signalized intersections as candidates for transit signal priority measures. The proposed method is suitable for application to most transit AVL/APC databases and is demonstrated using data from Grand River Transit, the public transit service provider in the Region of Waterloo, Ontario Canada.

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The travel times of public transit systems that operate on mixed use right-of-ways are often dictated by the delays experienced at signalized intersections. When these delays become large and/or highly variable, transit quality degrades and agency operating costs increase. A number of transit priority measures can be applied, including transit signal priority or queue jump lanes. However, it is necessary that a process of prioritizing intersections for priority treatment be conducted so as to ensure the greatest return on investment is achieved. This thesis proposes and demonstrates a methodology to determine the distribution of stopped delays experienced by transit vehicles at signalized intersections using archived AVL (automated vehicle location) and APC (automated passenger counting) data. This methodology is calibrated and validated using queue length and bus unscheduled stopped delay data measured at a field site. Results show the proposed methodology is of sufficient accuracy to be used in practice for prioritizing signalized intersections for priority treatment. On the condition that a sample of the transit vehicle fleet is equipped with an AVL/APC system, the proposed methodology can be automatically implemented using the archived AVL/APC data and therefore avoid the need to conduct dedicated data collection surveys. The proposed methodology can provide estimates of (1) the maximum extent of the queue; and (2) measures of the distribution of stopped delays experienced by transit vehicles (e.g. mean, standard deviation, 90th percentile, etc.) caused by the downstream traffic signal. These measures can be produced separately for different analysis periods (e.g. different times of the day; days of the week; and time of the year) and can be compiled separately for different transit routes. These outputs can then be used to identify and prioritize signalized intersections as candidates for transit signal priority measures. The proposed method is suitable for application to most transit AVL/APC databases and is demonstrated using data from Grand River Transit, the public transit service provider in the Region of Waterloo, Ontario Canada.

A high resolution speedy delivery time domain reflectometer (SD/TDR) has been developed in the Electrical Engineering department at The University of Texas at Austin. The SD/TDR uses a novel non-sinusoidal signal that does not undergo dispersion during transmission in a lossy media. SD/TDR is used to estimate the length and detect the location of faults in the transmission lines. Time of flight (TOF) is one of the critical parameters of SD/TDR and a function of several temperature dependent factors. Given the TOF and length of a transmission line, signal delay can be computed. This research presents an empirical study of the effect of temperature on the TOF in a plenum grade coaxial cable for temperatures ranging from -3 °C to 60 °C. We also study the effect of temperature on characteristic impedance of the coaxial cable. Finally, a SD double exponential waveform is used to estimate TOF for calibrated short and open terminations. / text