Date of Award

Fall 2009

Document Type

Thesis

Degree Name

Master of Science in Electrical Engineering - (M.S.)

Department

Electrical and Computer Engineering

First Advisor

Timothy Nam Chang

Second Advisor

Durgamadhab Misra

Third Advisor

Edwin Hou

Abstract

This work presents the hardware and software architecture for the detection of fractures and edges in materials. While the detection method is based on the novel concept of Low Transient Pulse (LTP), the overall system implementation is based on two digital microelectronics technologies widely used for signal processing: Digital Signal Processor (DSP) and Field Programmable Gate Array (FPGA). Under the proposed architecture, the DSP carries out the analysis of the received baseband signal at a lower rate and hence can be used for large number of signal channels. The FPGA's master clock runs at a higher frequency (62.5MHz) for the generation of LTP signal and to demodulate the passband ultrasonic signals sampled at 1MHz which interrupts the DSP at every 1 [Is. This research elaborates on designing a Quadrature Amplitude Modulator - demodulator (QAM) on the FPGA for the received signal from the ultrasound and edge detection on the DSP processor to detect the presence of edges/fractures on a test Sawbone plate. In this work, the LTP technology is applied to determine the location of the Sawbone plate edges based on the reflected signals to the receivers. This signal is then passed through a QAM to get the maxima (peaks) at the received signal to study the parameters in the DSP. This work successfully demonstrates the feasibility of modular programming approach across the two platforms. The dual time scale platform readily accommodates higher temporal resolution needed for the generation of Low Transient Pulses and the processing of real time baseband signals on the DSP for various test conditions.

Share

COinS