An initial progress report on testing at the University of Oklahoma between hearing aids and wireless phones indicates some interference exists but makes no conclusions at this time.
“The key objective is to evaluate short-term and long-term solutions that will enable people with hearing aids to use the new digital wireless phones,” said Hank Grant, chairman of the board of directors for the OU Center for the Study of Wireless Electromagnetic Compatibility.
Phase I of the OU Center test will aim to determine the existence and severity of interference according to hearing aid type, phone technology and hearing loss configuration.
The three phone technologies used in current testing are Global System for Mobile communications at 1900 MHz, Time Division Multiple Access Interim Standard 54 at 800 MHz, and Code Division Multiple Access IS-95 at 800 MHz. TDMA and CDMA technologies will be tested at 1900 MHz when prototypes of those phones are available, said A. Ravi Ravindran, project director at the OU Center.
Eighteen of 75 people participating in the study have been tested, so conclusions are premature, Ravindran said. Thus far, research indicates there is some degree of interference between digital phones and hearing aids, but the extent has not been identified because of the limited sample size. Also, radio frequency shielding in the phones and hearing aids helps reduce interference, and the feasibility of shielding will be pursued, the report states.
Testing of all 75 people is scheduled to be completed by the end of March and a report should be issued in April. The OU Center is funded by the Cellular Telecommunications Industry Association, the University of Oklahoma and the National Science Foundation.
