Two LC circuits (each with its own coil) are used in either or both of an external controller or an implanted medical device to extend the range at which the two devices can communicate. Only one of the LC circuits (i.e., one of the coils) is used when the device is transmitting, while both LC circuits (i.e., both coils) are used when the device is receiving. When receiving, the LC circuits are preferably connected in series. The series connection of the LC circuits does not affect the resonant frequency, and thus this resonant frequency is the same for both transmission and reception despite the different LC circuits used. Switching circuitry is controlled to disconnect one of the LC circuits when the device is transmitting, and to connect the LC circuits in series during reception.
