Wireless network system and reception quality measurement method

A wireless network system comprising:

• a plurality of wireless devices that each have a unique identifier and transmit/receive a radio signal;
• and
• a controller configured to perform an operation sequentially with respect to each of the plurality of wireless devices by:
• instructing one wireless device among the plurality of wireless devices to broadcast a measurement signal that includes the unique identifier of that wireless device;
• and
• instructing the other wireless devices to receive the measurement signal and to measure reception quality, which depends on the distance between the wireless devices based on the measurement signal received, and to transmit reception quality information including the measured reception quality to the controller, and
• obtaining an arrangement of the plurality of wireless devices using distances between the wireless devices based on the reception quality information.