Abstract: A system includes a light source, a photodetector in optical communication with the light source, and a processor in communication with said photodetector and configured to output a signal representing oxygen saturation independent of an interfering signal from an interfering source. The system may further include an analog-to-digital converter in communication with the processor that is configured to digitize a signal from the photodetector by oversampling and output oversampling data to the processor. The processor may include an averaging filter that averages the oversampling data received from said analog-to-digital converter prior to decimation to generate an oversampling number.

Abstract: A sensor for measuring physiological characteristics includes a circuit assembly, at least one material layer, and an adhesive layer that extends beyond an outer edge of the circuit assembly. The at least one material layer forms an adhesive edge around the perimeter of the sensor.