Home > Highlights > Electromagnetic Radiation and Human Health

Electromagnetic Radiation and Human Health

Do you carry your cell phone in your pocket? Maybe you use a two-way radio or other portable wireless device. Every time you use a portable wireless device to transmit, your body is absorbing electromagnetic radiation from the device. The effect of this radiation on human health is frequently the subject of debate, as are the Federal Communications Commission’s (FCC) limits on the maximum specific absorption rate (SAR) of electromagnetic radiation that the body can safely absorb. (SAR is measured in Watts per kilogram and is influenced in part by the transmission power of the device.) A byproduct of the demand for higher performance, many wireless devices are nearing current FCC limits. Notre Dame researchers are working to improve device performance without increasing health risks.

Electromagnetic research takes place in ND’s anechoic chamber where a mannequin that mimics human tissue is used to model the effects on the body when the devices are held in lifelike positions.
Standard designs of portable wireless devices, such as a cell phone, typically involve a single transmitter in the device, which effectively creates a “hot spot” of radiation at the point where the antenna and amplifier are located. A three-year, $1.2 million project, recently funded by the National Science Foundation, focuses on transforming current engineering and designs of portable wireless devices in order to lower SAR for a given performance level or increase performance for a given SAR level. The multi-university research team, led by Bertrand Hochwald, the Freimann Chair Professor of Electrical Engineering, is exploring the concept of replacing a device’s single-transmitter with multiple transmitters located at different points on the device, without changing the SAR constraint or reducing performance.

The key to success may prove to be the distributed transmitters, which, under a power constraint, may have lower SAR than a single transmitter for the same level of performance. Achieving this innovative use of the transmitters, however, involves modeling electromagnetic radiation and its effects on the human body, as well as modeling their effect on wireless device performance.

Team members include Patrick Fay, professor of electrical engineering, who will address microwave modeling; David Love, professor of electrical and computer engineering at Purdue University, who will focus on signal processing and modeling analysis; and Jianming Jin, the Y.T. Lo Chair Professor in Electrical and Computer Engineering at the University of Illinois at Urbana-Champaign, who will focus on electromagnetics.