Harmonic allocation of cochlea implant frequencies

A system for fitting a cochlea implant system to a patient comprising:

• a first implantable stimulation unit with a first electrode array including a plurality of electrodes configured to apply an electrical stimulation to auditory nerve fibers of a cochlea of the patient;
• an external unit including a memory unit which comprises a natural frequency allocation model;
• and
• a frequency allocating unit configured to allocate a plurality of characteristic frequencies to each electrode of the first electrode array according to a frequency allocating scheme, wherein the frequency allocating scheme including;
• determining an insertion angle of at least one electrode of the first electrode array,
• determining a plurality of natural frequencies as a function of a cochlea spiral length based on the natural frequency allocation model and the insertion angle,
• determining the plurality of characteristic frequencies as a function of a cochlea spiral length by frequency downshifting the plurality of natural frequencies until a predetermined frequency allocation objective is obtained and while preserving the harmonic relationship between the natural frequencies of the plurality of natural frequencies in the plurality of characteristic frequencies, and
• programming the cochlea implant system to allocate the plurality of characteristic frequencies to each electrode of the first electrode array based on the insertion angle of the at least one electrode.