System and method for wireless, low-loss transmission in conductive medium of a radio-frequency signal received by a passive array of magnetic dipole elements from a source magnetic dipole. The individual elements are separated from one another by a distance on the order of or less than a quarter-wavelength corresponding to resonant radio-frequency. An array individual elements of which are microscopically dimensioned form a neuronal transmitter that can be configured to be implanted into neuronal tissue such that a source dipole, disposed near a neuron, passes a signal representative of neuronal activity along the array to an outmost element and further to external receiver disposed near skull. Macroscopically-dimensioned embodiment is configured to be submerged into and operate in salty water.