It is shown that interactions between artificially injected whistler mode waves and electrons can be strongly enhanced if the frequency and amplitude of the injected signal are appropriately programmed. The frequency variation produces efficient and steady changes in the particles energy and pitch angle through an extension of the cyclotron-resonance interval. The amplitude modulation might prove necessary in certain interactions to avoid instability of the phase trapping mechanism. Sixteen interactions evolving in a duct centered at a geomagnetic field line with L = 4 are studied by following the (test particle) evolution of the equatorial pitch angle and energy, and obtaining the required (ground) transmitter spectrogram format. Transmission using the proposed modulation with sufficient accuracy to match the real magnetosphere appears feasible and could be attempted in the near future.