A system for treating disordered breathing comprising: a. an electrical pulse generator capable of providing electrical stimulation signals to a phrenic nerve or diaphragm of a patient at a predetermined signal frequency； b. a respiration sensor capable of sensing a signal representative of the patient's respiration； c. a frequency comparator that compares the spectral power of the frequency distribution of sensed respiration signals over a stimulation frequency band to the spectral power of sensed respiration signals over a respiratory frequency band； and d. power adjusting circuitry that adjusts the power of the electrical stimulation signals provided by the electrical pulse generation based on the comparison of the spectral power values.
