A communication method of a data collection system including a data collection device, and at least one wireless communication device, selecting one wireless channel among a plurality of wireless channels, and holding a wireless communication between the data collection device and the wireless communication device, the communication method comprising:
- causing the wireless communication device to start measuring a first time when the wireless communication device receives a wireless signal from the data collection device;
- when the wireless communication device receives another wireless signal from the data collection device before the first time exceeds a first predetermined time, causing the wireless communication device to remain on the one wireless channel selected from the plurality of wireless channels;
- and
- when the wireless communication device does not receive another wireless signal from the data collection device before the first time exceeds the first predetermined time:
- causing the wireless communication device to change to another wireless channel, and to transmit a detection signal for detecting the data collection device and to start measuring a second time after changing to the other wireless channel,
- causing the wireless communication device to determine a new channel for communication with the data collection device as the other wireless channel when the wireless communication device receives a response signal from the data collection device in response to the detection signal before the second time exceeds a second predetermined time, and
- causing the wireless communication device to change to a further wireless channel and to transmit another detection signal when the wireless communication device does not receive the response signal from the data collection device in response to the detection signal before the second time exceeds the second predetermined time.