Featured Researcher Dr. Patrick ChiangDr. Patrick Chiang

(L-R) Patrick Chiang works with engineering students Sean Connell and Samuel House on investigating Indoor, Three Dimensional, High Resolution Tracking of Elderly Patients.

Dr. Patrick Chiang is an assistant professor in the Department of Electrical and Computer Engineering at Oregon State University.  He received the BS in electrical engineering from University of California, Berkeley in 1998 and hisPhD degree from Stanford University in 2007.  Since fall 2006, he has been at OSU where he directs the VLSI (Very Large Scale Integration) Research Group.  Prior to joining OSU, he was involved with several semiconductor startups in Silicon Valley.  In 2006, he was a visiting NSF researcher at Tsinghua University, China, working on adaptive wireless collaborating on energy-efficient UWB transceivers.  He is currently a senior visiting researcher at Fudan University, China, collaborating on energy-efficient UWB transceivers. He is the 2010 recipient of the Department of Energy Early CAREER award for the project entitled “Sustainable Silicon:Energy–Efficient VLSI Interconnect for Extreme-Scale Computing”.

Two Core Areas of Research

1) Energy-efficient communications for future semiconductor microchips
2) Ubiquitous, low-cost, wireless, medical sensors for enabling healthy aging

While at first glance it might seem that these two goals are unrelated, it turns out that one of the most critical requirements for future medical sensors is low power consumption.  For example, implantable wireless pacemakers, insulin pumps, and Parkinson’s neurostimulators need to monitor organ vital signs in the body for 5-10 years, placing important requirements on the battery life.  Non-invasive health monitoring, such as wearable sensors for measuring heart rate, pulse oximetry, or movement,  will need to consider energy consumption in order to reduce battery size and total sensor cost.  In all of these applications, the movement of data around (for example, between wired chips or through wireless communications) is the dominant source of power consumption – typically more than 90% of the total system power.  Hence, the design of energy-efficient communications at multiple levels is tantamount to achieving both of these research goals.

Two Specific Research Project with Local Oregon Organizations

1) Wireless tracking and localization of indoor-3D movement of elderly in their homes (with Huaping Liu (OSU); ORCATECH at OHSU)

The goal of this work is to monitor the 3D movement patterns (to less than a foot resolution) of elderly as they move around their homes.  With a small wireless transceiver, preliminary data shows the ability to achieve 6-10cm distance resolution of two patients walking within their home.  This movement tracking technology may enable early diagnosis of dementia, which is highly correlated with walking patterns, as well as continuous safety monitoring such as acute falls.

Related Publications:

Seungjin Baek, Ruiqing Ye, Charles Hu, Stephen Redfield, Huaping Liu, Tamara Hayes, and Patrick Chiang, "Preliminary Study of Indoor Ultrawideband Localization for At-Home Patient Monitoring", AMA-IEEE Medical Technology Conference on Individualized Healthcare, Washington DC, March 2010.

Karthik Jayaraman, Qadeer Khan, Baoyong Chi, William Beattie, Zhihua Wang, and Patrick Chiang, "A Self-Healing 2.4GHz LNA with On-Chip S11/S21 Measurement/Calibration for In-Situ PVT Compensation," Radio Frequency Integrated Circuits (RFIC) Symposium, Los Angeles, CA, May 2010.

Changhui Hu, Rahul Khanna, Jay Nejedlo, Kangmin Hu, Huaping Liu, and Patrick Y. Chiang, "A 90nm-CMOS, 500Mbps, Fully-Integrated IR-UWB Transceiver Using Pulse Injection-Locking for Receiver Phase Synchronization", Radio Frequency Integrated Circuits (RFIC) Symposium, Los Angeles, CA, May2010.

2) Wireless, non-invasive brain-computer interfaces for the continuous monitoring of neurological diseases (with Electrical Geodesics in Eugene)

Non-invasive monitoring of brain function and health is important for understanding neurological diseases such as depression, stroke, epilepsy, as well as many others.  Conventional brain imaging techniques have been limited to bulky, inaccurate, expensive hardware that has changed minimally over the past 30 years.  Due to recent advances in semiconductor technology (for example, giving us modern cell phones and consumer electronics), it is now possible to build low-cost, wireless, brain imaging interfaces that are massively integrated into a single microchip.  Using off-the-shelf components, we have built a 1st generation prototype the size of the quarter that can monitor a patient’s single EEG channel.  We are currently working on a next-generation microchip that incorporates hundreds of channels of brain sensors, performs local compression computation, and wirelessly transmits the data for further analysis.  With the proposed technology, it will then be possible to monitor and analyze brain behavior at one’s home – eliminating costly hospital visits and the associated infrequent neurological assessments that can lead to poor diagnosis.

Related Publication:

R. Albright, B. Goska, P.Y. Chiang, "A Wireless Transceiver Platform for Comparing Various ISM Bands for Next-Generation Body Area Networks", AMA-IEEE Medical Technology Conference on Individualized Healthcare, Washington DC, March 2010.