Method and apparatus for measuring biological signal

A method of measuring a biological signal of a body using an apparatus for measuring the biological signal, the method comprising:

• obtaining signals from the body using at least three interfaces;
• applying a signal having a frequency higher than a frequency of interest of the biological signal to at least one of a first interface from among the at least three interfaces and one of a plurality of internal elements of the apparatus;
• generating a feedback signal from component signals generated due to the applied signal using a signal obtained from at least one of a second interface and a third interface from among the at least three interfaces;
• receiving the generated feedback signal, controlling a signal input from at least one of the second interface and the third interface and sending the controlled signal to an amplifier;
• and
• outputting a measured biological signal of the body using the controlled signal.

An apparatus for measuring a biological signal of a body, the apparatus comprising:

• at least three interfaces which obtain signals from the body;
• a signal application unit which applies a carrier signal to at least one of a first interface from among the at least three interfaces, and one of a plurality of internal elements of the apparatus;
• and
• a feedback signal generation unit which generates a feedback signal from component signals generated due to the applied carrier signal, using a signal obtained from at least one of a second interface and a third interface from among the at least three interfaces,
• wherein the carrier signal is synthesized based on a signal having a frequency higher than a frequency of interest of the biological signal, and the feedback signal received from the feedback signal generation unit, and is output from the signal application unit.