Experimental estimation of EMI from cellular base-station antennas on implantable cardiac pacemakers

The impact of electromagnetic interference (EMI) from cellular base station (BS) antennas on implantable cardiac pacemakers is clarified in this article. The estimation of the impact is based on in vitro experiments that are conducted using simulated multicarrier and multicode signals, which are transmitted from actual BS antennas and dipole antennas as the radiation source of the BS antenna. Critical interference to the electric field strength is revealed with respect to the 800-MHz band second-generation and 2-GHz band third-generation cellular systems. The experimental results show two things. One is that the pacemaker EMI depends on the average power of the transmission signals and does not depend on the peak-to-average power ratios of the transmission signals, which increase with the number of multicarriers and multicodes. The other is that the boundary of the EMI area where malfunctions occur closely approximates the contour of a 25-V/m electric field that is exited from a commercially available collinear array antenna typically used in BSs. Furthermore, no pacemaker EMI is detected in the immediate vicinity under the BS antenna at an input power level for typical operation. Accordingly, it is clear that the pacemaker EMI should not pose a concern in residential environments.