Engineering Commons^™

A Novel Ultrasound Imaging Technique Using Random Signals, Anahita Khalilzadeh

Electrical Engineering Theses and Dissertations

Ultrasound imaging has been used extensively because of its benign nature and relatively low cost implementation. The most common approach for forming an image is Brightness Mode (B-Mode), which uses an array with dynamic focusing. Focus is performed through Phase Shifters that are bulky and complicated components which increases the device cost.

This research describes a new method to form an Ultrasound image, without relying on phase shifting. The proposed method offers a lower cost solution compared to the B-Mode systems and overcomes some of their inherent limitations.

Using Gs/S Adc To Evaluate The Emi Of Gan-Based Power Devices, Chi Zhang

Electrical Engineering Theses and Dissertations

As the silicon-based power devices are gradually reaching their performance limits, new power transistors such as Silicon Carbide (SiC) and Gallium Nitride (GaN) FETs have been rapidly developed in recent years. GaN devices have been widely accepted by researchers for its higher speed and efficiency than silicon power devices. However, despite all its merits, the GaN device faces a more severe problem of electromagnetic interference (EMI) than the silicon device due to its high performance. Various control techniques of EMI have been studied so far and many of them require the evaluation of EMI. Research shows that the EMI level …

Investigating The Effect Of Detecting And Mitigating A Ring Oscillator-Based Hardware Trojan, Lakshmi Ramakrishnan

Electrical Engineering Theses and Dissertations

The outsourcing of the manufacturing process of integrated circuits to fabrications plants all over the world has exposed these chips to several security threats, especially at the hardware level. There have been instances of malicious circuitry, such as backdoors, being added to circuits without the knowledge of the chip designers or vendors. Such threats could be immensely powerful and dangerous against confidentiality, among other vulnerabilities.

Defense mechanisms against such attacks have been probed and defense techniques have been developed. But with the passage of time, attack techniques have improved immensely as well. From directly observing the inputs or outputs, adversaries …

High-Speed Single-Channel Sar Adc Using Coarse And Fine Comparators With Background Comparator Offset Calibration, Guanhua Wang

Electrical Engineering Theses and Dissertations

A 1-GS/s 8-bit single-channel successive-approximation-register (SAR) analog-to-digital converter (ADC) using coarse and fine comparators with fully background comparator offset calibration is presented. Low-power coarse comparators and low-noise fine comparators are both employed to improve the comparator power efficiency. Non-binary digital-to-analog converter (DAC) with redundancy is employed to tolerate possible errors in the most-significant-bit (MSB) decisions. A novel comparator offset calibration scheme is proposed to remove the offsets between the different comparators, without slowing down the speed of the SAR conversion. The prototype ADC is simulated in a 28 nm CMOS technology and achieves an SNDR of 42.13 dB near Nyquist …

Linear Phase Multi-Frequency Notch Filter Via Quadratic Programming, Yueran Ma

Electrical Engineering Theses and Dissertations

Discrete-time notch filters can be divided into infinite impulse response (IIR) and finite impulse response (FIR) notch filters. Infinite impulse response notch filters are easy to design and implement but suffer from nonlinear phase characteristics and unacceptable startup transients. Finite impulse response filters on the other hand can be designed to have linear phase but require more coefficients to achieve narrow notch widths. Multiple frequency FIR notch filters that can effectively reject several selected spectral regions while providing high transmission at frequencies outside the rejected regions have applications in communication systems, radar systems and biomedical signal processing.

A new multi-frequency …