초록 ▼

For radio data (DT) transmission by media access based on a CSMA scheme in a system, such as a radio LAN, wherein a source node retransmits a DT frame if an ACK monitor IFS interval S lapses following forward transmission of the DT frame before reception of an ACK frame which a destination node back

For radio data (DT) transmission by media access based on a CSMA scheme in a system, such as a radio LAN, wherein a source node retransmits a DT frame if an ACK monitor IFS interval S lapses following forward transmission of the DT frame before reception of an ACK frame which a destination node backward transmits an ACK transmission IFS interval T (longer than the interval S) following due reception of the DT frame, a transmission mode is forward changed from an original mode of the forward transmission to a slow mode if retransmission fails with the original mode twice and the slow mode later used for backward transmission. Each of the source and the destination nodes is put, in the original mode, in a waiting state for afresh use as either a source or a destination node after a data transmission IFS interval D (longer than the interval T) either when the source node receives the ACK frame in the original or the slow mode or if the ACK frame is not received even the retransmission is repeated a predetermined number of times, when the DT frame is discarded with the backward transmission given up.

대표청구항 ▼

[ What is claimed is:] [1.] A method of transmitting frames by media access based on a carrier sense multiple access scheme in a radio data transmitting system comprising a plurality of nodes comprising at least first, second, and third nodes, the method comprising the steps of forward transmitting

[ What is claimed is:] [1.] A method of transmitting frames by media access based on a carrier sense multiple access scheme in a radio data transmitting system comprising a plurality of nodes comprising at least first, second, and third nodes, the method comprising the steps of forward transmitting a data frame from said first node to said second node, backward transmitting an acknowledgement frame from said second node to said first node when said second node duly receives said data frame, and retransmitting said data frame from said first node to said second node when said first node does not receive said acknowledgement frame within an acknowledge monitor interframe space interval following an instant of the step of forward transmitting, wherein said second node backward transmits said acknowledgement frame with a higher priority degree than transmission of another data frame from said third node, said method further comprising at said first node the steps of forward changing a transmission mode of transmission of said data frame to a slow mode when no acknowledgement frame is received from said second node during progress of said step of retransmission and backward changing said slow mode towards an original mode of said step of forward transmitting when said acknowledgement frame is received from said second node within the acknowledge monitor interframe space interval after retransmission of said data frame during the progress of said step of retransmission.