Apparatus and method of communicating data employing current pulses transmitted by an implanted device through living biological tissue to an external device. The method also contemplates transmission of current pulses from the external device through living biological tissue to an implanted device. Uniquely configured antenna electrodes are preferably employed in the implanted device. Increase in signal-to-noise ratio is achieved through synchronization. The method may be employed in diagnostic, therapeutic and general monitoring activities in connection with human beings.