A means for unobtrusive and ubiquitous detection and monitoring of heart and respiration activity from a distance could be a powerful tool for health care, emergency, and surveillance applications, yet remains a largely unrealized goal. Without contact or subject preparation (special clothing, attachments, etc.), this could better extend health monitoring to the chronically ill in routine life, allow wellness monitoring for a large population without known predisposition for risk or harm, and provide alarm and data in emergencies. Such technology could also be used to detect lost or hidden subjects, to help assess emotional state, and to compliment more cumbersome measurements as pre-screening. Doppler radar remote sensing of vital signs has shown promise to this end, with proof of concept demonstrated for various applications by the UHM PI.s and others. Unfortunately, this principle has not been developed to the level of practical application, mainly due to a lack of an effective way to isolate desired target motion from interference. However, by leveraging recent advances in signal processing and wireless communications technologies, this technique has the potential to transcend mere novelty and make a profound impact on health and welfare in society. We propose to explore robust radar monitoring techniques by isolating desired radar return signals from unwanted motion through recent developments in multiple input multiple output (MIMO) signal processing techniques, developed to enhance wireless communications channel capacity through constructive use of multipath phenomenon. The approach would involve three primary areas of research: (1) development of spatial-frequency algorithms for single and multiple source radar, (2) active radar system implementation using wireless terminals and/or silicon radar chips, and (3) development of an effective .pseudo-passive. sensing system where radio signals in the environment are harnessed for radar monitoring without control or specification of the signal source. The project will culminate with the demonstration of robust Doppler radar MIMO system capable of isolating and determining the number of subjects in the monitoring field, and measuring their heart and respiration rates.
Intellectual Merit: The proposed three-year collaborative research effort between the University of Hawaii at Manoa (UHM) and Bell laboratories (BL) would explore techniques for making non-contact Doppler radar sensing of cardiopulmonary activity a practical alternative or supplement to more cumbersome and invasive technologies that necessarily limit application. Recent work by the UHM PI and one Co-PI (Lubecke) to implement Doppler sensing by leveraging telecommunications technology, including the detection of heart and respiration signatures with wireless terminals, has attracted international attention for its potential. The second UHM Co-PI (Host-Madsen) is an established expert in statistical and communications signal processing with numerous publications in multi-user detection, estimation theory, and adaptive signal processing. The industry partner, BL, is widely considered the leader in the field of MIMO and other wireless systems technology. In related work, graduate students working with the PI have won three student paper competition awards in major IEEE MTT and EMB conferences.
Broader Impact: The outcomes of this project can lead to valuable tools beneficial for society in the areas of health care, emergency response, military, and security operations. The research would present a particularly motivating educational opportunity that leverages Hawaii.s unique needs for remote healthcare tools, and reaches out to a diverse population of ethnic minority students that have been historically underserved by local educational and industrial opportunities. Thus, an important aspect of this program will be interactions of UHM students with BL industrial co-advisors, involving extended periods of training in the highly relevant fields of communications and bio-sensing engineering, beyond the limits of the University (and Hawaii), at BL in a world-class research environment. The partnership established will allow UHM students and faculty to complement UHM resources by leveraging BL.s considerable expertise and facilities without charge, including a broad range of wireless test systems.
