An efficient concatenated trellis code and coordinate interleaved orthogonal design for MIMO OFDM

Abstract

In this paper, we propose an efficient concatenated OFDM scheme with a trellis code and a coordinate interleaved orthogonal design (TC-CIOD). We derive a pairwise TC-CIOD codeword error probability upper bound showing that full spatial and high multipath diversities are achieved. This result also shows that the TC-CIOD achieves the diversity four times higher than the best reference system with the cost of moderate increase in encoding and decoding complexities. Next, we derive the design criteria for TC-CIOD by analyzing the codeword error probability. We further use these criteria for computer based exhaustive searches to find optimum constellation rotation angle and optimum trellis codes for TC-CIOD. Finally, we present the system level simulation results showing that TC-CIOD outperforms the best reference system by 10.7, 10.2, 4.8 and 4.2 dB in signal-to-noise ratio at the codeword error rate of 10 - 3 when 4, 8, 16 and 32-state trellises are used, respectively.