| 摘要 |
<P>PROBLEM TO BE SOLVED: To change a use frequency band of a whole system to a frequency band having excellent communication quality when communication quality of radio communication has deteriorated. <P>SOLUTION: In a time zone in which each apparatus uses an operational channel, a printer 20 stores reception states of regular packets transmitted by a controller 10, and calculates a reception success rate. Each apparatus makes a radio channel to be used shift to a scan channel when scan start time has come, and shift back to the operational channel when scan end time has come. During the scan is performed, the printer 20 stores reception states of regular packets transmitted by the controller 10 through the scan channel, and calculates a reception success rate. The controller 10: collects the success rates of the operational channel and scan channel; determines the scan channel to be a new operational channel when the success rate of the scan channel is higher; and notifies the printer 20 and a handy terminal 30 of it. <P>COPYRIGHT: (C)2013,JPO&INPIT |
