We propose a novel soft forwarding (SF) technique for wireless cooperative communication to minimize impact of the detection error at the relay employing decode-and-forward (DF) cooperation scheme. We make use of the soft information received by the relay to improve the system error performance, when the packets forwarded by the relay have errors. The challenge here is to implement the soft forwarding scheme over the existing wireless system platforms without much overhead or modification. To achieve this, the hard-decision bits of the soft information are transferred in a manner of the conventional DF scheme, while the magnitude of the log-likelihood ratio, defined as reliability, being computed by the destination based on the knowledge of the source-relay link signal-to-noise-ratio. T...[ Read more ]

We propose a novel soft forwarding (SF) technique for wireless cooperative communication to minimize impact of the detection error at the relay employing decode-and-forward (DF) cooperation scheme. We make use of the soft information received by the relay to improve the system error performance, when the packets forwarded by the relay have errors. The challenge here is to implement the soft forwarding scheme over the existing wireless system platforms without much overhead or modification. To achieve this, the hard-decision bits of the soft information are transferred in a manner of the conventional DF scheme, while the magnitude of the log-likelihood ratio, defined as reliability, being computed by the destination based on the knowledge of the source-relay link signal-to-noise-ratio. To discriminate the erroneous and error-free relayed packets, different combining methods are applied for different error cases. We also extend the idea of our one-bit SF scheme to the frameworks of coded cooperation and network coding as well. The simulation results verify that our scheme overcomes the defects of the DF scheme and outperforms the previous soft-DF schemes with respect to simplicity and overhead. The generality of our technique makes it useful in various applications and scenarios.