| 摘要 |
PURPOSE:To efficiently perform data communication by forming plural packets by respectively time-dividing plural channels, and respectively selecting any one of packets at an RF transmission part and an RF reception part. CONSTITUTION:An RF MODEM 10 on a subscriber side is provided with a CPU 11, system ROM 12 and CMOS memory 13 and equipped with an FSK modulation circuit 14 and an FSK demodulation circuit 15. Transmissive data from a personal computer 6 are supplied from the CPU 11 to the modulation circuit 14, and an FSK signal outputted from the modulation circuit 14 is supplied through an output amplifier 16 to a (t) side contact of a transmission/ reception changeover switch 17 and sent from a movable contact. Then, the plural channels are respectively time-divided into plural packets Pa, Pb...Pk, and each user performs personal computer communication while selecting arbitrary one packet Pi for one time of communication. |
