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920MHz Band Wireless Device (Korea) USERS MANUAL EM-9121 Rev. 1
6. PRELIMINARY MEASUREMENT OF RADIO WAVE ENVIRONMENT
In prior to building a wireless network, perform the following measurements to decide which channels to use and locations for install-
ing respective wireless devices.
• Channel noise scan
• Communication test
Execute a channel noise scan to measure RSSI values of respective channels.
Check the channel numbers not used on the perimeter.
Execute a communication test to measure the RSSI value and packet error rate (PER) between wireless devices in a specific chan-
nel.
Determine the number of wireless devices, installation locations, and necessity to set relay nodes, etc. based on the RSSI value and
the PER of each channel to use.
Note 1: To measure the radio wave environment, switch the mode of each wireless device from the normal mode to the measurement mode.
To switch the mode, refer to “6.3 TERMINATING MEASUREMENT TOOL” on page 51.
Note 2: The wireless connection is disconnected when the PAN ID of a parent device is set to ‘0000’.
Switch to the normal mode and change the PAN ID to, for example, ‘0001’.
Refer to the operating manual of the parent device specified in “8. SETTING WIRELESS DEVICES” on page 62 for how to
change the PAN ID.
Note 3: The wireless connection of a child device is disconnected when:
no channel number is set;
the short address is set to ‘0000’; and/or
no network name is set.
Switch to the normal mode and change each setting item.
Refer to the users manual of each child device specified in “8. SETTING WIRELESS DEVICES” on page 62 for how to change
the setting of each item.
Note 4: Switch the mode to the normal mode to change the setting of ‘Transmitter power output’.
Refer to the manual of each wireless device specified in “8. SETTING WIRELESS DEVICES” on page 62 for how to change the
setting.