Rapid and sensitive detection of stress hormones, such as cortisol and dehydroepiandrosterone (DHEA), can benefit the diagnosis of diseases related to adrenal gland disorders, post-traumatic stress disorders, chronic fatigue syndrome, and more. Stress hormones fluctuate in a circadian rhythm, the highest in the early morning and the lowest at night;...
This dissertation studies two different wireless microwave sensing applications in the subjects of environmental monitoring and biomedical devices. The environmental sensing application presents a design of novel wireless sensor node configurations. These nodes are intended to be used specifically in a built environment of railroad track ballast for its health...
Simultaneous speech-to-text translation remains a difficult yet important problem for modern machine learning models whereby a text translation is generated concurrently with receiving partial speech inputs. One state-of-the-art simultaneous speech-to-text model is the augmented memory transformer whose encoder breaks a speech input into fixed-size overlapping segments composed of left, right,...
Ring Amplifier serves as a great candidate both for precision amplification and fast integration in the discrete time system. It can be utilized in high-performance analog-to-digital converters (ADCs). In high-speed ADC utilizing pipelined architectures with residue amplification, Successive-Approximation Register (SAR) ADCs as the sub-ADC and power efficient Ring Amplifier based...
The deployment of advanced technology standards for 5G and beyond in cellular networks has resulted in interest in integrated circuits (ICs) operating at frequencies above 10GHz. This has sparked research on wideband circuits in commercial low-cost silicon technologies, operating at high RF and mm-wave frequencies. Given the wide range of...
The passive charge compensation (PCC) technique was introduced for switched capacitor (SC) circuit to increase the slew rate and enhance the linearity performance, as PCC techniques are used on the Delta-Sigma modulator (DSM) in ADC circuitry. The PCC technique of the project was applied to the design of a SC...
In recent years, the research community's interest in fully integrated mm-Wave wireless communication systems has increased significantly. With the standards for 5G NR now in place, the focus has shifted to actual deployment. Mm-Wave systems provide wider bandwidths, higher capacity, and lower latency than existing systems such as 4G. Higher...
The need for sustainably powering unobtrusive internet-of-things applications has led to an interest in energy harvesting. Particularly, the proliferation of wireless communication and devices in the 2.4 GHz Industrial Scientific c Medical (ISM) band creates an opportunity to leverage commonly used devices for RF powering. This dissertation presents a low-quiescent-power...
Silicon photonics has become the most promising platform for future large-scale optical interconnect and optical computing systems due to its inherent CMOS compatibility, which brings exclusive advantages in bandwidth density, energy efficiency, and cost effectiveness. Parallel optical interconnects based on photonic integrated circuits (PICs) have the capacity to meet the...
Transparent conductive oxides (TCOs), combining the optical transparency and electrical conducting properties, have attracted escalating research interests in recent years due to their potential for various photonic applications. The electrical and optical properties, such as carrier concentration, mobility, will strongly affect the performance of TCO-based photonic devices. In this dissertation,...
Magnetic materials can be used in modern soft robotics as a method for external stimulus actuation and motion control. By combining aspects of biology and mechanics, devices are fabricated to create a structure capable of complex movement. Applications that these devices are subject to can be broken down into four...
Advances in additive manufacturing technologies allow for the rapid, inexpensive manufacturing of microwave circuits. Circuits made using additive manufacturing are comparable in performance to circuits produced circuits produced using conventional methods such as printed circuit board fabrication, thin film deposition, machining, and milling. Very little work has been done in...
Metal grating based plasmonic filters are widely researched for their unique properties of field enhancement and localization of light beyond diffraction limit. However, the plasmonic grating filters reported in literature mostly have broadband outputs making them unsuitable for spectroscopy. In this project, we have designed, fabricated, and characterized an array...
This dissertation focuses on the application of diatom frustules, the biosilica shell of an algae possessing physical and photonic properties capable of enhancing optical signals, for the enhancement of optical sensing. In this work, we incorporate diatom frustules into biosensors for signal enhancement and improved target molecule detection. The potential...
Successive-approximation-register (SAR) analog-to-digital converters are popular for medium accuracy, medium speed and low power applications, such as in biomedical applications. They have low latency and simple architecture compared with ΔΣ ADCs. This is because of SAR ADCs’ binary searching scheme. Furthermore, SAR ADCs can apply oversampling and noise shaping schemes...
This research focuses on receiver architectures which enable better spectral eciency
by handling blockers in the same spectral range as the signal. The presence of
such blockers, without the use of blocker cancelling/ ltering techniques leads to gain
compression and hence, consequent performance degradation of receivers leading to
reduced spectrum...
Wearable sensors with an inertial measurement unit (IMU) are popular for indoor positioning and activity pattern detection. The IMUs can be connected to a wireless transmission module, allowing users to monitor and process motion-related parameters remotely. Because of the complexity and uncertainty of signals in indoor environments, a radio frequency...
Filters and data converters are key analog-and-mixed-signal (AMS) building blocks in communication systems, such as software-defined radios and internet-of-things. In this dissertation, novel switched-capacitor filter and analog-to-digital converter (ADC) circuit configurations have been explored which are power efficient and are digital scaling friendly.
First, a novel switched-capacitor low-pass filter architecture...
Real time indoor positioning awareness systems aim to add localization capabilities to upcoming wireless technologies that are quickly becoming an important feature for indoor environment. RF-based impulse-radio ultra-wideband (IR-UWB) is a promising technology for in-door positioning systems due to obstacle penetration capabilities, immunity to multi-path and fading, and high resolution....
This work presents an inductor less switched capacitor based energy harvester, which can simultaneously harvest from 2 energy sources (Solar + Piezo). The proposed harvester employs 2D maximum power point tracking algorithm, by changing the conversion ratios of the charge pumps for piezo and solar sources, and 1D voltage regulation...
The dissertation focuses on the engineering of light-matter interaction using plasmonic nanoparticles and metamaterials to achieve enhanced luminescence and based on which to improve the performance of biosensing and light-emitting technologies. We designed and fabricated a spectrum of nanostructures to exhibit particular dispersion relations capable of controlling the spontaneous emission...
Due to the advantages of the high surface area and high porosity, Metal-Organic Framework (MOF) materials are widely used in gas storage. As a typical MOF material, Zeolitic Imidazolate Framework-8 (Zif-8) has high selectivity and adsorption capability of carbon dioxide (CO2). In this thesis, we investigated the infrared absorption of...
The prevalence of Internet-of-Things (IoT) applications leads to an increasing focus on the design and optimization of sensor nodes. Battery lifetime and associated costs of battery replacement often limits the long term operation and viability of sensor nodes. RF wireless energy harvesting on the other hand can be appealing since...
Analog-to-digital converters are essential components to the portable devices that we are using today. Wireless sensors, body implanted devices, communication devices and so forth require low power ADCs. Therefore achieving higher resolution and bandwidth with lower power consumption is targeted in ADCs design. In this work power efficient ADCs for...
The need to detect trace amounts of target molecules is great, particularly when it comes to biosensing. With the early detection of a disease, the odds of the successful treatment of an individual increases significantly. To enhance the capability of biomolecular detection, we have created an optical biosensor capable of...
In this work, an alternating current (ac) magnetic susceptometer is designed and implemented to track the Brownian relaxation time of magnetic nanoparticles that are suspended in a liquid medium. The detection technique based on the Brownian relaxation time of magnetic nanoparticles has found its way in a variety of biosensing...
Hyperthermia is a cancer therapy that relies on the local heating of a cancerous tumor to kill cancer cells and disrupt the future growth of the tumor. While hyperthermia is capable of killing tumors separately, physicians often combine it with other treatment methods, typically radiation therapy, for its synergistic effects...
This dissertation focuses on extending the application scope of surface enhanced infrared absorption spectroscopy to gas sensing. The method we propose is incorporating plasmonic nanostructures with nano-composite material, metalorganic framework, which can selectively preconcentrate certain gas molecules into the nanopores. The preconcentrating property is first demonstrated by applying metal-organic framework...
Recent sensor System-on-Chips (SoC) have enabled significant advances in energy-efficiency by incorporating various micro-powered building blocks. Unfortunately, most of these sensor systems do not address the high power cost associated with data storage and transmission, which in some cases vastly exceeds the power consumed by the rest of the SoC....
This dissertation focuses on the analysis, design, and application of inductor-capacitor (LC) oscillators for wireless sensor networks (WSNs).
First an analysis and design optimization approach for enhanced swing, low power CMOS LC oscillators is presented. A phasor based analysis is used for determining the amplitude and phase noise of these...