| 摘要 |
Real time analog and digital information are simultaneously transmitted from a transmitter circuit. In the disclosed embodiment, the analog signals are obtained from ECG apparatus and the digital signals are derived by a process or from analysis of the ECG signals. The system is implemented by summing the output signals from the FM oscillator and the FSK oscillator in an amplitude summing amplifier and transmitting the result in combined waveform, preferably over a phone line, although radio transmission may alternately be used as well as other types of transmission of the resulting signal. In the present invention, the analog signal is employed to frequency modulate a frequency modulated oscillator, and the digital information signal is used to obtain frequency shift keying of a FSK oscillator. In the disclosed embodiment, the frequency modulated oscillator and the FSK oscillator have frequencies that are within the band pass of the telephone line and, of course, have sufficient separation so that the resulting output signal may be filtered and decoded to obtain the separate analog and digital components. After the FM modulated analog information signal and the digital controlled FSK signals are obtained, they are coupled to an amplitude summing amplifier which provides a single amplitude summation of the two signals as applied to the modem and thus over the phone line. In this manner, the simultaneous transmission of both analog and digital information is provided in efficient but effective system.
|
