Long-term Power Fluctuation and Delay Spread Characteristics in a Factory Environment at 2.4 GHz and 5.2 GHz Bands.

In order to measure the propagation channel characteristics in a factory environment, measurements were performed in the 2.4 GHz and 5.2 GHz bands to obtain the received power and delay spread at various locations. The received power at several fixed locations was recorded simultaneously to measure the long-term power fluctuations caused by the dynamic factory environment. Power fluctuations were also recorded from a receiver placed on an Automatic Guided Vehicle (AGV) which frequently moved around a fixed area within the factory. The probability distribution of the received power was compared with several distribution models, and results show that they can be modelled using the stable distribution. Furthermore, analysis of the relationship between delay spread and received power between several transmitter and receiver locations in the factory suggested that they are inversely correlated, where the delay spread increased when the received power decreased.