Experimental evaluation of MIMO coded modulation systems: Concatenation with OSTBC or spatial multiplexing

We evaluate the performance of several MIMO coded modulation schemes capable of extracting the maximum diversity and capacity from quasi-static MIMO channels: Bit Interleaved Coded Modulation (BICM) with spatial multiplexing or concatenated with a Space Time Block Code (STBC). Both simulations and measurements show that concatenation with STBCs is not necessary in order to retain maximum system capacity and spatial diversity. Simply spreading the output symbols of a BICM system among the different transmit antennas provides the same optimum performance. STBCs have the advantage of simplifying the implementation.