A simultaneous full-duplex speech and electrocardiogram communications system

A system has been developed allowing the simultaneous communication of full-duplex speech and multiple electrocardiograms in real time. A single bandlimited channel is used, a dial-up PSTN line providing a 3 KHz bandwidth. The full-duplex speech is compressed to 2400 b/s using linear predictive coding whilst multiple electrographic signals are processed by a novel ECG compression technique. Extensive use of digital signal processing reduces the combined bit rate to less than 9600 b/s, allowing the use of a cost effective commercial modem. The communication system allows a hospital based clinician to provide diagnostic and treatment advice to a remote location, thus improving patient care