The Use of a Field Programmable Gate Array in a Compact Ion Mobility Spectrometer Sensor System for Subsurface Volatile Organic Compound Detection

Contaminants such volatile organic compounds (VOCs) can prove to be harmful if they come in contact with our nation\u27s drinking wells. In order to ensure that the level of contaminants meets the standards set by the Environmental Protection Agency (EPA), contaminated sites must be monitored. Current methods for monitoring subsurface groundwater contaminants are costly and inaccurate; therefore there remains a need to develop an inexpensive monitoring system that can provide accurate results in a timely manner. In order to meet this need, Boise State University (BSU), with collaboration from Washington State University (WSU), has developed an inexpensive, minimally invasive, real-time miniature Ion Mobility Spectrometer (IMS) based sensor system that can be used for long-term monitoring of subsurface VOCs. This thesis presents the design methodologies and implementation of a FPGA based data acquisition and control system for use with the IMS based sensor system. This FPGA based data acquisition and control system was designed in a hardware/software co-design environment using an embedded soft-core processor. The design makes use of a FPGA to accelerate the digital signal processing algorithms and provide accurate IMS timing and control. An embedded soft-core processor was used to ease development by implementing non-time critical portions of the design in software. The design was successfully implemented using a low cost, off-the-shelf FPGA and supporting digital and analog electronics