A pulse reader for ionization chambers has been developed,
tested, and calibrated. An insulated gate field effect transistor
(IGFET) was used to detect the pulses and Victoreen Model 362
Pocket Chambers were used as ionization chambers. The energy
dependence of the Victoreen Model 362 Pocket Chamber was determined
to be...
This thesis presents methods for treating annihilation photon pairs in deterministic pulse height distribution (PHD) simulations. The methods are applied in PHD simulations for monoenergtic sources of 1.6 and 2.6 MeV photons incident on 5 and 10 cm 1-D slabs of germanium, sodium iodide, and lead and the results are...
We used two temporally separated femtosecond pulses to manipulate the waveforms of multi-cycle THz pulses through optical rectification in periodically-poled lithium mobate (PPLN). The relative phase of the THz pulses was controlled by the relative time delay between the optical pulses. This phase adjustability combined with the frequency tunability of...
In source-detector radiation transport simulations, pulse height distributions are a useful metric in assessing the effectiveness of nuclear instrumentation. In the area of spectroscopy, pulse height distributions are used to identify an unknown source. It is widely believed that pulse height distributions cannot be created using deterministic methods. This quantity...
The extremely fast ionization process in semiconductors offers a means of generating pulses that have sub -nanosecond rise times and high peak powers. There are several important applications of these pulses which require the duration of the generated pulse to be variable. This thesis investigates three methods of producing variable...
Time-domain data conversion has recently drawn increased research attention for its highly digital nature in favor of process technology scaling. Also, as the time information being carried by binary voltage, time-domain operation is much less sensitive to voltage noise compared to conventional voltage domain operation. However, for analog-to-digital converter (ADC)...
Voltage controlled oscillator (VCO) based ADC is an important class of time-domain ADC that has gained widespread acceptance due to their several desirable properties. VCO-based ADCs behave like an open-loop continuous time ΔΣ modulator and achieve excellent resolution by first order noise shaping the quantization error. However, the SNDR 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...
