An Improved Detection Scheme for Distributed IDM-STCs in Relay-Systems

This paper is concerned with the application of distributed Interleave-Division-Multiplexing Space- Time Codes (dIDM-STCs) in relaying systems with error-prone relays applying Decode-and-Forward (DF). In case of erroneous decoding at the relays, error propagation occurs which is not considered by the original detection scheme for IDM-STCs. Hence, a new Reliability Aware Iterative Detection Scheme (RAID) is proposed which takes the decoding success of the relays as well as their decoding reliability into account. By optimally incorporating this knowledge in the detection process at the destination, substantial performance gains compared to the original detection scheme are achieved. The proposed RAID scheme even outperforms adaptive relaying as it explicitly exploits also erroneous relays, which is not the case for the adaptive scheme.