A trellis coded beamforming scheme over MIMO fading channels

We analyze the performance of a trellis-coded beamforming scheme for a MIMO system over Rayleigh fading channels. It is assumed that the channel state information can be obtained at both transmitter and receiver. Before transmission, the coded symbols are weighted to maximize the received signal-to-noise ratio. We derive an upper bound for the pair-wise error probability and a closed-form expression for the exact average pair-wise error probability. It is shown that on slow Rayleigh fading channel, the minimum squared Euclidean distance between the pair-wise sequences should be maximized, while on fast Rayleigh fading channel, the code effective length and the product distances should be maximized to achieve higher performance gain. Furthermore, we show that this trellis coded beamforming scheme outperforms the space-time trellis coded beamforming scheme. Simulation has been conducted to verify the performance analysis. For the sake of practicality, simulation over imperfect channels is done to compare with simulation over perfect channels.