Real-Time RF Exposure Setup Based on a Multiple Electrode Array (MEA) for Electrophysiological Recording of Neuronal Networks

Real-time investigations on the effects of mobile-phone exposure on neuronal activity are considered the highest priority in the health risk assessment of RF fields. Therefore, this paper describes a new real-time exposure setup for electrophysiology recordings, combining an open transverse electro-magnetic cell with a multiple electrode array. The system was numerically and experimentally characterized at a frequency of 1.8 GHz, representative of the uplink band of the GSM1800. Finite-difference time-domain simulations were performed, as well as measurements of the S₁₁ scattering parameter and temperature increases for specific absorption rate (SAR) determination. The local mean SAR value near the solution-electrodes interface was evaluated from the temperature measurements and coincided with the simulated one. The same is true for S₁₁ measurements that were consistent with numerical results; hence, confirming the accuracy of the modeling. Nevertheless, nonuniform SAR distributions were observed near the recording electrodes. Good system efficiency was determined from both numerical analysis and experimental data. Thermal behavior was evaluated and a small temperature increment of 0.3°C for a local experimental SAR of 3.2 W/kg was measured.