Relaying technologies have been designated as major new enabling technologies for next generation wireless broadband systems, such as 3GPP LTE-Advanced. The practical deployment of decode-and-forward (DF) relaying technologies as supported by the current standard is based on repetition coding, meaning that the relay regenerates the same codeword generated by the source node. This scheme is suboptimal. Nevertheless, it is preferred in practice due to its simple implementation. The optimal relaying schemes called cooperative coding are difficult to construct in practice and require heavy computation load at the receiver. Therefore, they are rarely implemented despite their prospected performance gains. As a simple and practical alternative, we propose a novel relaying scheme that provides a superior performance similar to the advanced cooperative coding techniques, but it is less complex to implement. Our novel scheme is called "decode-partial-forward" (DPF) because its fundamental concept of operation is based on making the relay forwards one part of the source message such that the receiver at the destination node can rely on the direct channel with the source to obtain the other part of the message. The DPF scheme is based favorably on repetition coding and maximal ratio combining techniques, which are standardized techniques with low-complexity and low computation load. Nevertheless, our novel scheme performs very close to the optimal bounds for the supported rates over relaying links. More specifically, the increase in the supported reliable transmission rates (bits/sec) using the proposed DPF scheme may exceed 30% of the supported rates using the conventional repetition coding DF scheme. Another major advantage of our proposed scheme is that it is easy to adapt flexibly based on the channel conditions of the three links of the relay channel (source-destination, source-relay, relay-destination), by adjusting the power and rate allocation at the source and relay using simple closed-form analytic formulas. Therefore, we believe that the DPF relaying scheme is an excellent option for practical deployment in the telecommunication standards due to its simplicity, adaptability and high spectral efficiency gains.


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