author = {P. Weitkemper and D. W\"{u}bben and V. K\"{u}hn and K.-D. Kammeyer},
  year = {2008},
  month = {Jan},
  title = {Soft Information Relaying for Wireless Networks with Error-Prone Source-Relay Link},
  URL = {http://www.mk.tu-berlin.de/scc08/},
  address={Ulm, Germany},
  abstract={Relays in wireless networks can be used to decrease transmit power while additionally increasing diversity. Distributed turbo coding as a special case of decode-and-forward is very powerful in relay networks when assuming error free decoding in the relay. In practical wireless networks, however, this assumption is only justiļ¬able if an ARQ protocol is applied which leads to lower throughput. Soft-reencoding and transmission of the reliability of reencoded bits helps the destination to decode the message. Reencoding in the relay with a recursive convolutional code as used for turbo-codes, can lead to error propagation. In this paper the effects of error propagation in relay networks are investigated and more suitable distributed coding schemes are presented for soft-reencoding. As the often used assumption of Gaussian distributed disturbance at the destination is not valid for the considered system setup, the calculation of Log-Likelihood-Ratios (LLR) for the received noisy reliability information is derived analytically.},
  booktitle={7th International ITG Conference on Source and Channel Coding}