Some new codes for space-time trellis encoded modulation over fading ISI channels

Wireless communication systems are disturbed by multipath effects which alter widely the signal amplitude. In such cases coding and diversity schemes are usually employed to lower error rates. It is well known that space-time encoded trellis modulation schemes achieve good performance for transmission through slow fading with perfect CSI. Design criteria used to build space-time codes over slow fading is maximizing rank and determinant from matrices made with codewords pairs. Defining a small size encoder structure and making an exhaustive search over all possible codes with that size, optimum encoders were found. Simulations results are displayed in terms of bit error rate over channels subjected to Doppler and ISI effects.