Abstract: An apparatus for non-invasively estimating bio-information and a method of determining whether a bio-signal is normal by the apparatus for estimating bio-information are provided. The apparatus for estimating bio-information according to an embodiment of the disclosure includes: a photoplethysmogram (PPG) sensor configured to measure a PPG signal from an object; and a processor configured to extract a plurality of pairs of local maximum points and local minimum points from a second derivative signal of the PPG signal, to select at least one reference pair from among the extracted plurality of pairs, and to determine whether the PPG signal is normal based on the selected at least one reference pair.

Abstract: A repeater and method for automatically setting output signal level of the repeater is disclosed. The repeater includes: a voltage detection unit for measuring a voltage of signal amplified by a plurality of the amplifiers; a digital variable resist unit for providing a reference voltage value Vref; a comparison unit for comparing the detected voltage Vdec from the voltage detection unit and the reference voltage value Vref from the digital variable resist unit; and a control unit for setting output signal level of the repeater by controlling the digital variable resistor unit to generate the reference voltage Vref to be identical to the detected voltage Vdec and controlling an output of repeater based on the comparison result from the comparison unit after setting the output signal level of the repeater.

Abstract: A repeater and method for automatically setting output signal level of the repeater is disclosed. The repeater includes: a voltage detection unit for measuring a voltage of signal amplified by a plurality of the amplifiers; a digital variable resist unit for providing a reference voltage value Vref; a comparison unit for comparing the detected voltage Vdec from the voltage detection unit and the reference voltage value Vref from the digital variable resist unit; and a control unit for setting output signal level of the repeater by controlling the digital variable resistor unit to generate the reference voltage Vref to be identical to the detected voltage Vdec and controlling an output of repeater based on the comparison result from the comparison unit after setting the output signal level of the repeater.