Bio-signal measuring apparatus and bio-signal measuring method

A bio-signal measuring apparatus, comprising:

• a first electrode;
• a second electrode;
• a third electrode;
• a fourth electrode;
• a first circuit network and a second circuit network, each of the first circuit network and the second circuit network includes one or more resistances;
• an impedance measuring circuit configured to:
• measure a first impedance of the first circuit network in a first correction mode in which the one or more resistances having known values are connected;
• measure a second impedance of the second circuit network in a second correction mode in which the one or more resistances connected in the first correction mode, are disconnected by closing a switch that forms a bypass current path of each of the one or more resistances;
• measure a body impedance of an object in a measurement mode, using the first electrode, the second electrode, the third electrode, and the fourth electrode;
• and
• a processor configured to:
• obtain an internal parameter of the impedance measuring circuit, based on the first impedance of the first circuit network in the first correction mode and the second impedance of the second circuit network in the second correction mode;
• and
• obtain a bio-impedance of the object, based on the internal parameter, and the body impedance of the object in the measurement mode.