Capacity and spatial correlation measurements for wideband distributed MIMO channel in aircraft cabin environment

In this paper we present some channel measurement results of distributed multiple-input multiple-output (D-MIMO) systems inside a MD-82 aircraft. Channel capacity and spatial correlation are analyzed from the measured channel matrix. Capacity results of 7 different systems (six D-MIMO systems and a SISO system) are discussed. It is found that D-MIMO systems yield significant capacity gains as compared to SISO system. Spatial correlations among transmitter (Tx) antennas distributed above the cabin aisle are statistically analyzed from the measured data. Result shows that, when receiver (Rx) antenna array is placed in the front or back of the cabin, some Tx antenna pairs are highly correlative (correlation coefficients are higher than 0.8). The effect of Tx antenna selection on capacity characteristic of in-cabin D-MIMO system is also studied. It is found that Tx antenna selection can further improve channel capacity and the optimum selected Tx antennas are usually the ones near to the Rx array.