MIMO channel measurements inside an aircraft cabin with planar transmit antennas

With standardization of MIMO-OFDM spatial multiplexing in IEEE 802.11n, the interest of the industry in chances and risks of this technology is growing. Experiences with planar transmit antennas applied with an experimental MIMO radio system and changing transmitter side interantenna spacing are reported in this paper for an indoor aircraft environment. Different transmission scenarios are described and results are compared and discussed. The paper focuses on the effect of interantenna spacing on the capacity of MIMO channels. Growing transmitter interantenna spacing yields different power levels for each transmit antenna at the receiver. Especially in environments with high obstacle density which cause electromagnetic shadows, high path losses for single transmit antennas may occur. This reduces the MIMO channel capacity.