Wireless, RF & Smart Dust

Research that includes:

  • Tuneable RF components: capacitors, inductors, transformers
  • RF microrelays
  • High frequency MEMS resonators: devices, structures, and processes

BPN803: Single Chip Mote

Alex Moreno
Titan Yuan
Austin Patel
Abanob Bostouros
Lydia Lee
2022

The single chip micro mote 3C (SCµM-3C) was designed to be a wireless sensor node on a chip capable of joining a network as a bare die with a standards compliant BLE and 802.15.4 mesh communication radio while fully self-contained and functional with no external components. SCµM-3C’s deep level of integration allows users to connect a battery, program using a touchless optical programmer and be ready to connect to the network. As a sensor, SCµM-3C was shown to have a ~1 cm accurate 3D localization estimate and measure temperatures from 0 to 100C with <2 C of precision....

NT18: MEMS RF Switch with Liquid Gallium Contacts

Qingquan Liu
2006

A self-healing MEMS RF switch, which utilizes liquid gallium contacts to take the place of the traditional metal-to-metal hard contacts, is proposed in this project. Electrostatic actuation is used to drive a silicon nitride diaphragm with upper electrodes. When the diaphragm is pulled down by the electrostatic force, small droplets of liquid gallium work as an interface between the upper and lower electrodes. The loss of the gallium droplets can be avoided due to the unwettability of the material surrounding the contact areas. In this project, hermit package and 1A DC current...

NT11: Tunable Inductors and Transformers Utilizing Electro-Thermal Vibromotors

Wen-Pin Shih
Zhihong Li
2004

The goal of this project is to develop on-chip tunable inductors and tunable transformers which have high inductance value and high tuning ratios. The potential applications include performance optimization and functionality enhancement to wireless communication, magnetic microsensors, and micromagnetic power devices, such as dc/dc converter.

Project end date: 08/18/04

NT13: RF Dielectric Fluid Immersed Silicon MEMS Tunable Capacitors

Daniel T. McCormick
Zhihong Li
2004

The objective of this project is to develop micro-electromechanical tunable capacitors employing dielectric fluids. In the case of electrostatic, mechanically tunable capacitors the goal is to increase the capacitance per unit area and the tuning range, reduce the mechanical noise and also improve mechanical performance and long-term reliability.

Project end date: 08/18/04

NT14: A Variable Inductor Array Using Lateral-Contact Microrelays

Ye Wang
Zhihong Li
2003

The objective of this project is to develop a variable inductor array using lateral-contact microrelays to provide a wide tuning range and design flexibility for building blocks using passive RF MEMS components in wireless communication systems.

Project end date: 01/27/04

BPN987: Single-chip µV Precision ADC for SCµM-V (New Project)

Yu-Chi Lin
Daniel Lovell
2022

We are developing a mm-square low-power wireless ADC that will detect and transmit microvolt signals, which is promising for precision measurements in biomedical applications, automotive, and mobiles. This project specifically aims to be used for a concurrent TMS-EEG-fMRI system, a highly desirable temporal and spatial imaging method to unveil the mystery of brain circuits. The precision ADC will make it possible to acquire EEG signals down to 10µV while wireless transmission will avoid safety heating issues by current induced in wired-loop under time-varying magnetic field in MRI....

BPN976: Fully-Integrated MEMS-Based Wireless Receiver (New Project)

Kevin Zheng
2022

Recent MEMS process advancements from our group have enabled a class of low-temperature, thin-film ruthenium RF filters that can be processed directly on top of CMOS wafers. This work seeks to demonstrate the first low-IF receiver with fully-integrated MEMS-based RF channel-select filters, which permits low power applications in high-sensitivity, narrow-band software-defined communications and cognitive radio.

BPN953: Long-Term Drift of MEMS-Based Oscillators

Xintian Liu
Kevin H. Zheng
QianYi Xie
2022

This project seeks to characterize and de-mystify mechanisms behind long-term drift in MEMS-based oscillators, including ones employing various sustaining amplifiers and referenced to resonators constructed in a variety of materials, including silicon, polysilicon, AlN, diamond, and ruthenium. A measurement apparatus that suppresses unwanted sources of drift, e.g., temperature, to better focus on resonator and oscillator long-term drift will be instrumental to success and will likely entail the use of double or triple ovens, as well as environment resistant circuit design.

BPN859: High Frequency Oscillator Characterization

Kevin H. Zheng
QianYi Xie
Xintian Liu
Kieran Peleaux
2022

This project aims to study and understand fundamental mechanisms that govern phase noise, aging, thermal stability, and acceleration stability in high frequency micromechanical resonator oscillators.

BPN871: An Ultrasonic Implantable for Continuous In Vivo Monitoring of Tissue Oxygenation

Soner Sonmezoglu
2022

Our group previously demonstrated a “neural dust” system for neural recording which includes an implantable device and external ultrasonic transducers to power and communicate with the implantable. In this work, we extend that paradigm, demonstrating an implantable that can measure and report tissue oxygenation. Oxygenation state is a key parameter when assessing the metabolic state of cells and tissues, tissue and organ viability, tumor state, among many examples in both basic science and clinical care. Various types of methods for the detection of oxygen have appeared in recent...