Getting a Buzz Out of Hearing Aids Eric Burwood Many hearing aid users have access to a mobile phone network using the analog mobile phone system (AMPS). In Australia this system will be shut down in many areas from 1 January 2000. The current 900 MHz GSM (Global System for Mobile Communications) digital mobile phone system has been operational since 1993 and Telstra will introduce a new digital mobile communication system during 1999 based on code division multiple access technology (CDMA) in the 800 MHz band. The Australian Government has also auctioned radio spectrum in the 1800 MHz band that may also be used for cellular mobile phones. Research conducted in Australia and overseas has shown that digital mobile communication systems may cause interference to some models of hearing aids. The interference may be perceived as a "buzz", a "static-like" sound, or sometimes as "white noise" depending upon the type and operating mode of the digital mobile. Hearing aids can be designed to have immunity to these digital radio signals and allow many hearing aid users to have access to digital phone networks. This paper discusses the results of research into the cohabitation of hearing aids with digital mobile phones. |