Wireless communication apparatus and wireless communication method

Abstract

A wireless communication apparatus for performing wireless communication using at least one of the first channel having the first frequency band, and the second channel having the second frequency band which is wider than the first frequency band includes a channel search device which executes the first channel search for the bandwidth of the first frequency band and the second channel search for the bandwidth of the second frequency band, and obtains a search result indicating an idle channel, and a determination device which determines a channel to be used on the basis of the search result obtained by the channel search device.

1 . A wireless communication apparatus comprising: 
 a channel search device configured to execute a first channel search for a bandwidth of the first frequency band an idle channel having a first-frequency-bandwidth and a second channel search for a bandwidth of the second frequency band an idle channel having a second-frequency-bandwidth, and obtain a search result indicating the idle channel having the first-frequency-bandwidth or the idle channel having the second-frequency-bandwidth, wherein the second-frequency-bandwidth is wider than the first-frequency-bandwidth;    a determination device configured to determine a channel to be used on the basis of the search result obtained by the channel search device; and    a communication device configured to perform wireless communication using one first-channel of two first-channels each having the first-frequency-bandwidth, or perform wireless communication using a second-channel having the second-frequency-bandwidth, the two first-channels and the second-channel being accessed in accordance with Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) in a Basic Service Set (BSS).    
   
   
       2 . The apparatus according to  claim 1 , wherein the channel search device limits a search range of bandwidth for the first channel search on the basis of the search result obtained by the second channel search.  
   
   
       3 . The apparatus according to  claim 1 , wherein the second-frequency-bandwidth is an integral multiple of the first-frequency-bandwidth.  
   
   
       4 . The apparatus according to  claim 1 , further comprising a periodic signal transmitting device configured to transmit a periodic signal on the idle channel in order to keep the idle channel found by the channel search device.  
   
   
       5 . The apparatus according to  claim 1 , further comprising a device configured to transmit a continuous signal on the idle channel in order to keep the idle channel found by the channel search device.  
   
   
       6 . The apparatus according to  claim 1 , wherein the determination device determines that at least two idle channels, each having the first-frequency-bandwidth and found by the first channel search, are used as at least one said second-channel.  
   
   
       7 . The apparatus according to  claim 6 , wherein said at least two idle channels have adjacent frequency bands.  
   
   
       8 . A wireless communication method comprising: 
 executing a first channel search for an idle channel having a first-frequency-bandwidth and a second channel search for an idle channel having a second-frequency-bandwidth, and obtaining a search result indicating the idle channel having the first-frequency-bandwidth or the idle channel having the second-frequency-bandwidth, wherein the second-frequency-bandwidth is wider than the first-frequency-bandwidth;    determining a channel to be used, on the basis of the search result obtained; and    performing wireless communication using one first-channel of two first-channels each having the first-frequency-bandwidth, or performing wireless communication using a second-channel having the second-frequency-bandwidth, the two first-channels and the second-channel being accessed in accordance with Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) in a Basic Service Set (BSS).    
   
   
       9 . The method according to  claim 8 , further comprising limiting a search range of bandwidth for the first channel search on the basis of the search result obtained by the second channel search.  
   
   
       10 . The method according to  claim 8 , wherein the second-frequency-bandwidth is an integral multiple of the first-frequency-bandwidth.  
   
   
       11 . The method according to  claim 8 , further comprising transmitting a periodic signal on the idle channel in order to keep the idle channel.  
   
   
       12 . The method according to  claim 8 , further comprising transmitting a continuous signal on the idle channel in order to keep the idle channel.  
   
   
       13 . The method according to  claim 8 , wherein said determining includes using at least two idle channels each having the first-frequency-bandwidth and found by the first channel search as at least one said second channel.  
   
   
       14 . The method according to  claim 13 , wherein said at least two idle channels have adjacent frequency bands.