| 摘要 |
PURPOSE: A method of performing packet communication of a power line communication system is provided to set a range of a present time delay value of a node ousted from a present priority to a smaller range than the maximum value among the prior time delay values, and to give a priority to the node by setting a random time delay value, thereby carrying out packet communication by obtaining channels according to the set priority. CONSTITUTION: When the third node and the fourth node attempt to obtain channels for packet communication with the first node, the third and the fourth node retrieve whether a signal of a power line is detected according to a channel signal and a virtual signal(ST1,ST2). If the signal is not detected, one of the third and the fourth node, which has a short virtual signal length, obtains a channel and performs the packet communication with the first node(ST3-ST5). When the other node without an obtained channel and the fifth node attempt to carry out the packet communication with the first node, the other node sets a range of a time delay value to a smaller range than a maximum value range, and sets a random time delay value(ST6). The fifth node retrieves whether the signal of the power line is detected according to the channel signal and the virtual signal(ST7). If the signal is not detected, one of the other node and the fifth node obtains a channel to carry out the packet communication with the first node(ST8,ST9). The other node without the obtained channel sets the range of the time delay value to a smaller range, and sets a random time delay value, then retrieves whether the signal is detected(ST10,ST11,ST12). If not, the other node obtains a channel to execute the packet communication with the first node.
|
