Summary
International Symposium on Antennas and Propagation
2010
Session Number:3TD3
Session:
Number:3TD3-2
Hearing Aid Compatibility Improvement for Mobile Phones.
Sangha Lee, Minsu Kim, Hyungchul Kim, Austin Kim, Jhon Lee, Douglas Kim, Jungho Park, Youngoo Yang,
pp.-
Publication Date:2010/11/23
Online ISSN:2188-5079
Summary:
HAC indicates the electromagnetic interference level, which is regulated by FCC, between the terminal and the hearing aid in order to avoid discomfort from people with impaired hearing, while they are using mobile terminals. More than 28 million people in USA (more than 1/10 of population) are using hearing aids [1]. There are two HAC approval items for the types of hearing aids. RF-emission is evaluated by measuring the electric and magnetic fields that are emitted toward the receiver and have carrier frequency of the terminal. T-coil measures the magnetic field at the voice band in the receiver of the terminal. Compared to T-coil, RF-emission is more closely related to the emission performance of the portable terminal [1]-[4] Presently, there are two methods by which the HAC Performance can be improved [4]-[6]. One is dual parasitic element (DPE) method. The other is adjusting the performance so that there is no margin of emissions performance in the business Spec. DPE method has problems, such as interference with sub-antennas and causing lack of mounting space, as portable terminals become more and more multifunctional and miniaturized. This paper presents a new HAC improvement method which has low interference with subantennas by decreasing the number of parasitic elements.