Frequency dependency of propagation along a lift shaft on board a merchant ship

Frequency dependency of wave propagation along a lift shaft on board a merchant ship is presented based on wideband channel measurement results. The maximum variation in the amplitude of the propagating waves and on the Root Mean Square (RMS) delay spread are found to be higher at 5200 MHz than 2414 MHz. The variation in average channel gain is found to be frequency independent. Although the maximum usable bandwidth is slightly lower for 2412 MHz; the higher Wi-Fi frequency of 5200 MHz has a higher propagation loss and is more sensitive to the temporal variation. Therefore, 2412 MHz is recommended for the WLAN application onboard ships with a maximum usable data rate of 1.7 Mbps for a BPSK system.