Gain control for a periodic signal and method regarding same

摘要

A gain control method for providing a gain controlled signal representative of a periodic physiological parameter of a patient includes providing a signal characteristic of the periodic physiological parameter. The periodic physiological parameter includes a plurality of periodic cycles. Gain of the signal is updated only once per periodic cycle following detection of a periodic event. The updating is performed by monitoring an amplitude of the signal between detection of periodic events and comparing the amplitude to a gain control amplitude threshold. Gain of the signal is updated as a function of the comparison. Further, gain is updated following expiration of a predetermined period of time if a periodic event is not detected within the predetermined period of time. The physiological parameter may be respiratory effort. An apparatus for providing such gain control is also provided.