RF implanted antenna gain characterization: Procedures and challenges

Preliminary research shows that implanted antenna gain characterization is a complicated issue and common measurement procedures in anechoic chambers are not directly applicable. Finding appropriate phantom size depends upon the part of the body involved, location of the implant, frequency of operation and plane of propagation of the communication link. A procedure to define the correct size has been proposed for horizontal plane transmission by a subcutaneous implant in the human torso. In addition, due to the particular low implanted antenna gain and unbalanced currents, the impact of feeding cable is decisive in the final results. Baluns, attenuators and/or optical feeding are required in this kind of measurement set-ups.