Patent ID: 9717463
Date: 2017-08-01
CPC Classifications: A61B,H03L

Claim:
1. A biological information measurement apparatus comprising: a sensor configured to detect a biological signal; a phase/frequency comparator configured to output a deviation signal based on a phase difference/frequency difference between the biological signal and an oscillation signal; a loop filter configured to block a signal of a predetermined frequency band contained in the deviation signal; a voltage controlled oscillator coupled to the phase/frequency comparator and configured to generate the oscillation signal based on the deviation signal that has been filtered by the loop filter; a low pass filter coupled to an output of the loop filter, the low pass filter having a variable cutoff frequency to selectively block a signal of a predetermined frequency band contained in the deviation signal that has been filtered by the loop filter; and a computer processing unit configured to analyze a phase, a frequency, and a SN ratio of the biological signal and change the variable cutoff frequency of the low pass filter based on the analyzed phase, frequency and SN ratio of the biological signal.