| 摘要 |
PROBLEM TO BE SOLVED: To provide a data communication system, where data can be transmitted at a high speed with low power consumption by omitting negotiation of a data communication link, when conducting data communication through the use of a channel of a portable telephone system. SOLUTION: When the speech channel of a portable radio telephone system is formed with a data communication opposite party between a data transmission terminal and a data collection device, the data transmission terminal transmits the data to the speech channel through the radio telephone terminal as a dial signal. Thus, the data are sent to the data collection device in the form of a DTMF signal. |
