Experimental results using a MIMO test bed for wideband, high spectral efficiency tactical communications

This paper presents results from a MIMO measurement campaign designed to demonstrate spectral efficiencies of 13.7-26.0 information bits per second per Hz (bps/Hz) using an 8times8 test bed over a range of outdoor wireless channels with low antenna heights at each end of the link. Links included line-of-sight and non-line-of-sight channels obstructed by foliage and buildings. Measurements were performed at 456, 904, and 2177 MHz using a variety of array configurations including multiple polarization configurations. The transmitted MIMO OFDM signal occupied a 5 MHz bandwidth and used several error control coding and interleaving strategies. Signal processing at the receiver employed iterative detection with spatial filtering, SISO demappers, BCJR-based decoding (for turbo codes), and soft-cancellation of self-interference. Results demonstrated successful link closure at spectral efficiencies up to 26 bps/Hz using real-world synchronization, channel estimation, and carrier-frequency offset tracking