Measured Multi-User MIMO Capacity in Aircraft

The multipath richness typical of aircraft channels represents a potentially well-suited environment for multi-user multiple-input multiple-output technology (MU-MIMO). This paper presents results from measurements of the achievable MU-MIMO data rates in a Rockwell T-39 Sabreliner, using an open-source software-defined radio (SDR) test bed. We also compared the achievable capacity of dirty-paper coding (OPC) against time-division multiple access (TDMA) to illustrate the value of advanced MU-MIMO techniques in aircraft environments. Measured data was then compared against values obtained from a three-dimensional ray-tracing simulation. For transmitters located near the ends of the aircraft, the average error between simulated and measured capacity was on the order of 2% or less. For the more-centralized transmitter location, simulations predicted an average of 6% less capacity than what was actually measured.