| 摘要 |
<p>PURPOSE:To use one operating frequency only and to avoid crosstalk by providing a transmission/reception equipment of the same frequency to plural terminal equipments respectively, discriminating whether or not a data is sent from other terminal equipment before data transmission and executing the data transmission when no data is sent. CONSTITUTION:The entire system consists of n-set of terminal equipments of the same constitution and a center. A CPU10 of the terminal equipment 1 at idle state discriminates the existing mode and when the transmission mode is set, a data sent from a receiver 19 is checked and whether or not a frequency fo signal is received is discriminated. When not received, that is, the transmission line is opened, the transmission data is sent in the frequency fo via a data transmission section 11 and a transmitter 17. In the terminal equipment 1, the transmitter 17 is driven and a high frequency signal sent from a transmission antenna 16 is received by a reception antenna, demodulated by the receiver 19 and the result is sent to a data transmission section 11. The CPU10 discriminates whether the reception data and the transmission data are coincident, the transmission mode is released when coincident and the data transmission is executed again when dissident.</p> |
