Cooperative multilevel dynamic space-time trellis coding scheme for improved system performance

This study proposes a system that employs multilevel coding scheme with dynamic space-time trellis codes (DSTTCs) as component codes in order to cooperatively transmit the information of mobile nodes to a common destination node. Perfect channel state information is available at both transmitter and receiver. Every mobile node has a DSTTC encoder at each information level, which receives feedback information from destination node and adapts to the current channel conditions by modifying its code set of generator sequences. The feedback information is in the form of an index of predefined channel profile with power gain in close proximity to the power gain of current channel profile at destination node. The proposed cooperative multilevel dynamic space-time trellis coding (CMLDSTTC) system has the potential of improving spectral efficiency, system throughput, diversity gain, coding gain with low decoding complexity. The CMLDSTTC system outperforms cooperative multilevel space-time trellis coding (CMLSTTC) system with predefined space-time trellis codes and non-cooperative multilevel dynamic space-time trellis coding system by similar to 5 and similar to 2.5 dB, respectively, at frame error rate of 10(-2) using two transmit and two receive antennas. The performance of CMLDSTTC system improves further with an increase in the bits of feedback information.