| 摘要 |
<p>A method and an apparatus for transmitting and receiving a voice signal simultaneously with a video signal via a single transmission line in a video phone. The apparatus comprises video signal receiving means for discriminating if a carrier frequency in the video signal being sent via the transmission line from a counterpart is which of a second frequency or a third frequency set within a frequency band of transmission line, demodulating the video signal with one of the second and third frequencies depending upon the discriminated result, and outputting the demodulated video signal to a displaying monitor; and video signal transmitting means for inputting the video signal from a self-camera, modulating the video signal with the other of the second and third frequencies and outputting the modulated video signal to the transmission line. The method comprises the steps of turning on/off power, designating the second frequency or the third frequency as carrier frequency of the video signal for transmitting, and performing only voice telephone call. In accordance with the present method arid apparatus, the simultaneous transmission and reception of the video signal between a caller and the counterpart can be established via the single transmission line in the video phone, as well it is possible to send the voice signal simultaneously with the video signal via the single transmission line in the video phone.</p> |
