| 摘要 |
PROBLEM TO BE SOLVED: To allow a device that cannot detect data transmission to prompt another device to re-transmit data.SOLUTION: A communication system comprises: a first communication device that transmits a transmission advance notice of data and then transmits the data; and a second communication device that, after receiving the transmission advance notice, transmits a negative acknowledgement signal to the first communication device if it cannot detect data transmission corresponding to the transmission advance notice. Upon receipt of the negative acknowledgement signal, the first communication device performs the retransmission processing of the data.SELECTED DRAWING: Figure 3 |
