Patent ID: 8140011

Claim:
A method of constructing a multi-hop radio system including a plurality of radio nodes among which are ad-hoc connected in a tree structure and carry out multi-hop communication, wherein: a first radio node among the plurality of radio nodes acquires, from at least two second radio nodes in the plurality of radio nodes, state information including identification information of a root node of a group to which each of the second radio nodes is ad-hoc connected; the first radio node selects a radio node from the second radio nodes as a first connection-accepting radio node based on a predetermined condition and connects to the first connection-accepting radio node; and in the case where the first radio node reselects a radio node to be a second connection-accepting radio node after the connection between the first radio node and the first connection-accepting radio node is disconnected, the first node selects a radio node as the second connection-accepting radio node, whose identification information of the root node included in the state information acquired from the radio node is the same as identification information of a root node of a group to which the first radio node is ad-hoc connected and connects to the second connection-accepting radio node.