Methods and apparatus for adaptive filtering of signals of continuous analyte monitoring systems

Inventors

Russo, Anthony P.

Assignees

Ascensia Diabetes Care Holdings AG

Abstract

A method of filtering a signal in a continuous analyte monitoring system (CAM) includes applying adaptive filtering to the signal using an adaptive filter to generate a filtered continuous analyte monitoring signal during an analyte monitoring period, and increasing the adaptive filtering applied to the signal as a function of increasing noise on the signal. Other methods, apparatus, continuous analyte monitoring devices, and continuous glucose monitoring devices are also disclosed.

Core Innovation

The invention relates to adaptive noise-dependent filtering of a continuous analyte monitoring signal, where a noise level is computed in an environment and used to control filtering during an analyte monitoring period. The system generates a signal in the environment using one or more biosensors, with a working electrode and a counter electrode, and measures a current associated with the working electrode as proportional to an analyte concentration.

Adaptive filtering is applied to the signal to generate a filtered continuous analyte monitoring signal by using an adaptive filter that varies with the noise level. The adaptive filtering comprises switching one or more low-pass filters into a closed state, where the one or more low-pass filters include one or more cut-off frequencies, and the switching is a function of the noise level such that all of the one or more low-pass filters are switched into the closed state when the noise level is zero.

The signal is passed through the one or more low-pass filters such that frequencies of the signal are filtered out upon reaching the one or more cut-off frequencies, and the one or more cut-off frequencies are changed as a function of the noise level. The adaptive filtering is increased as a function of increasing noise level to a following signal generated by the biosensors, thereby increasing adaptive filtering/attenuation when noise increases.

Claims Coverage

The partial content includes two independent claims. Both independent claims center on adaptive noise-dependent filtering of a continuous analyte monitoring signal generated by biosensors, with low-pass filter switching based on a computed noise level and increased filtering/attenuation as noise increases.

Across the independent claims, the coverage is directed to generating a continuous analyte monitoring signal from biosensors using working and counter electrodes, computing a noise level in the environment, and using that noise level to control adaptive filtering by switching low-pass filters into a closed state and adjusting cut-off frequencies, such that filtering or attenuation increases with increasing noise level.

Stated Advantages

Documented Applications