Method for setting packet transmission path in ad hoc network, and network apparatus using the same

A method of setting a packet transmission path to determine a relay node transmitting a packet between a source node and a destination node in a wireless communication network, the method comprising:

• determining N number of hops based on a delay time permitted with respect to a packet to be transmitted, N denoting an integer greater than or equal to two;
• setting N−1 routing regions including at least one node between a source node and a destination node based on the number of hops;
• transmitting, by either the source node or a first relay node transmitting the packet received from the source node, a Request To Send (RTS) message to nodes in the routing regions;
• determining a node having transmitted a Clear To Send (CTS) message as a second relay node, wherein the CTS message includes an estimated channel gain greater than a predetermined value, and a channel gain being estimated by each node having received the RTS message;
• and
• changing the predetermined value to compare a channel gain being estimated with the changed predetermined value;
• wherein the source node and the relay nodes set transmission power based on the predetermined N number of hops, the hop distance, and the distance from the center of each of the N−1 routing regions to the boundary.

A method of setting a packet transmission path to determine a relay node transmitting a packet between a source node and a destination node in a wireless communication network, the method comprising:

• determining N number of hops based on a delay time permitted with respect to a packet to be transmitted, N denoting an integer greater than or equal to two;
• setting N−1 routing regions including at least one node between a source node and a destination node based on the number of hops;
• transmitting, by either the source node or a first relay node transmitting the packet received from the source node, a Request To Send (RTS) message to nodes located in the routing regions;
• and
• determining a node having first transmitted a Clear To Send (CTS) message as a second relay node, wherein the CTS message includes an estimated channel gain based on a back-off time corresponding to the estimated channel gain, and a channel gain being estimated by each node having received the RTS message;
• wherein the source node and the relay nodes set transmission power based on the predetermined N number of hops, the hop distance, and the distance from the center of each of the N−1 routing regions to the boundary.

A wireless communication network apparatus comprising:

• a source node which determines a N number of hops based on a delay time permitted with respect to a packet to be transmitted and sets N−1 routing regions including at least one node between the source node and a destination node based on the number of hops;
• a first relay node which receives coordinate information of a destination node from the source node, estimates a channel gain, and transmits a response message to the source node where the estimated channel gain is greater than a predetermined value;
• and
• a second relay node which receives a message from the destination node, estimates a channel gain, and transmits a response message to the destination node where the estimated channel gain is greater than a predetermined value;
• wherein the source node and the relay nodes set transmission power based on the predetermined N number of hops, the hop distance, and the distance from the center of each of the N−1 routing regions to the boundary.