Patent ID: 8366628

Claim:
An apparatus for sensing biological signals from an animal, the apparatus comprising: at least one set of electrodes that is adapted to be placed in contact with tissue of the animal at a set of locations to sense biological signals; a set of insulated conductors connected to the at least one set of electrodes, the set of insulated conductors formed in a configuration adapted to be substantially immune to electromagnetic interference; a network of filters connected to the set of insulated conductors and configured to filter the biological signals and thereby produce filtered biological signals; an amplifier connected to the network of filters and having an internal voltage reference, the amplifier configured to amplify the filtered biological signals to provide an amplified differential signal, wherein the internal voltage reference also is connected to a node in the network of filters; an energy source for powering at least the amplifier and configured to be free of all ground connections external to the apparatus; and a signal analysis module configured to receive and analyze the amplified differential signal to determine at least one physiological parameter of the animal.