Image Number 5 for United States Patent #5467775.
A modular auscultation sensor and telemetry system ("MASTS") for sensing body sounds of a patient in a noisy environment where both desired body sounds and undesirable noise may be detected. The MASTS includes a transducer head that comprises two sensors that are substantially acoustically and mechanically isolated from each other. The first sensor is positioned to sense body sounds of a patient when the transducer head is placed against a patient's skin, and the second sensor is positioned to sense primarily noise, if any. The sound signals are transmitted to a digital signal processor carried in a waist-pack or similar container. The digital signal processor processes the sound signals using an adaptive filter scheme to produce an output signal that is indicative of primarily of the body sounds emanating from the patient. A receiving device such as earphones, a hybrid noise reduction ("HNR") headset, an HNR helmet, a tape deck, or a computer may be plugged into the waist-pack and coupled to the digital signal processor to receive the output signals.