Radio node apparatus, multi-hop radio system, and multi-hop radio system constructing method

A method of constructing a tree-structured multi-hop radio system including a plurality of radio node apparatus, at least a portion of which is used as a repeater for carrying out multi-hop communication at layer 2, comprising:

• a step in which, for selecting a host connection-accepting radio node, an arbitrary radio node apparatus of said plurality of radio node apparatus broadcasts a state information acquiring request to said plurality of radio node apparatus, other than said arbitrary radio node apparatus, each of which has state information including the total number of radio node apparatus connected to a tree-structured group with which each of the plurality of radio node apparatus has a connection, the number of hops from a root node positioned at a summit of said tree-structured group, identification information on said root node and its own identification information;
• a step in which said arbitrary radio node apparatus of said plurality of radio node apparatus receives said state information from said plurality of radio node apparatus other than said arbitrary radio node apparatus;
• and
• a step in which said arbitrary radio node apparatus of said plurality of radio node apparatus makes a comparison between the total number of radio node apparatus included in the received state information and the total number of radio node apparatus included in its own state information to select the radio node apparatus having said state information including the total number of radio node apparatus larger than the total number of radio node apparatus included in its own state information for selecting and connecting, of the selected radio node apparatus, the radio node apparatus having the smallest number of hops included in said state information as said host connection-accepting radio node apparatus.

A radio node apparatus for use in a tree-structured multi-hop radio system including a plurality of radio node apparatus, at least a portion of which is used as a repeater for carrying out multi-hop communication at layer 2, said radio node apparatus comprising:

• a transmission unit for broadcasting a state information acquiring request, used for section of a host connection-accepting radio node apparatus, to said plurality of radio node apparatus, other than said radio node apparatus, each of which has state information including the total number of radio node apparatus connected to a tree-structured group with which each of said plurality of radio node apparatus has a connection, the number of hops from a root node positioned at a summit of said tree-structured group, identification information on said root node and its own identification information;
• a reception unit for receiving the state information from said plurality of radio node apparatus other than it;
• and
• a control unit for making a comparison between the total number of radio node apparatus included in the received state information and the total number of radio node apparatus included in its own state information to select the radio node apparatus having the state information including the total number of the radio node apparatus larger than the total number of radio node apparatus included in its own state information and further to select and connect, of the selected radio node apparatus, the radio node apparatus having the smallest number of hops included in the state information as said host connection-accepting radio node apparatus.