| 摘要 |
PURPOSE:To send a graphic in a real time by converting a signal representing position information of the graphic outputted from a graphic input device into a digital data, sending the data through a telephone line and using a filter provided to the transmission side and the reception side so as to eliminate the signal of the frequency band of the carrier. CONSTITUTION:A graphic input device 1 outputting an analog signal representing the position information of an inputted graphic, analog/digital converters 4, 5 converting the output signal of the device into a digital data, a parallel/serial converter 10 converting it into a serial data and a modulator- demodulator (MODEM) 11 are provided to the sender side, and a demodulator 11 demodulating the modulation signal and the graphic output device 8 are provided to the receiver side. Moreover, a filter 13 eliminating the signal of the frequency band of the carrier used for the modulation is provided to a handset at the transmission and reception sides. Thus, the graphic is sent in real time by using a telephone line. |
