Title :
Transtelephonic electrocardiogram and voice signal transmitter-receiver system
Author :
Kejariwal, M. ; Winkley, M. ; Nett, Janice ; Jameson, William J., Jr.
Author_Institution :
Dept. of Electr. Eng., Montana State Univ., Bozeman, MT, USA
Abstract :
A transmitter-receiver communication system is developed to provide simultaneous voice and electrocardiogram (ECG) transmission capability via the public switched telephone network. The basic voice frequency passband of a telephone circuit is approximately 0-4000 Hz, of which the voice actually occupies roughly 200-3400 Hz. For dual-channel signaling (voice and ECG) the voice signal is bandlimited to about 2500 Hz (still providing intelligible speech quality) and is mixed with an ECG signal transported to a 3000-Hz center frequency. The ECG signal is passed through a 250-Hz low-pass filter and is amplitude-modulated on a 3-kHz carrier frequency. On the receiving side these two signal channels are separated, and the ECG signal is demodulated to the baseband using a phase-locked-loop technique. The ECG signal is displayed on a monitor. The hard copy of the ECG signal can also be obtained using a strip chart recorder.<>
Keywords :
biomedical equipment; electrocardiography; telemetering equipment; voice communication; 0 to 4 kHz; ECG transmission; dual-channel signaling; phase-locked-loop technique; public switched telephone network; telephone circuit; transmitter-receiver communication system; voice transmission;
Conference_Titel :
Engineering in Medicine and Biology Society, 1988. Proceedings of the Annual International Conference of the IEEE
Conference_Location :
New Orleans, LA, USA
Print_ISBN :
0-7803-0785-2
DOI :
10.1109/IEMBS.1988.95124
