The short-term effects of antenna insulation thickness on path losses in wireless telemetry implants at microwave frequencies

摘要: Various physiological parameters can be monitored non-invasively using wireless biotelemetry links. The development of sophisticated ultra low power consuming transceivers allows the transmission large amounts data from inside body to an external receiver in real time at microwave frequencies.Antenna impedance matching is crucial for obtaining acceptable propagation link budget a telemetry link. dielectric properties biological tissue induce detuning transceiver antennas when implanted into body. To counteract problems, implant are coated with biocompatible insulating material. study investigates losses communication different insulation thicknesses medical grade silicone Industrial-Scientific-Medical (ISM) radio band 2.45 GHz. consisted implantable unit which was placed between two pads substitute material and connected laptop. Predefined packets were transmitted implant, received analyzed, packet errors logged signal strength indicator values (RSSI) recorded. Our results showed that mean RSSI insulated transmitter - embedded equivalent provide more safety distance critical sensitivity level than uncoated antennas.The conducted measurements let us conclude increasing thickness layer, antenna becomes less sensitive by adjacent Therefore tuned influenced surrounding after implantation.