A hybrid relaying protocol for wireless cooperative networks based on the log-likelihood ratio

A Comparative Study on the Performance of LLR- and SNR-Based Hybrid Relaying Schemes

“…The performance is measured in terms of BER curves. It is then compared with different relaying schemes, namely, the hybrid relaying schemes presented in [6,9,11]. Figure 2 shows the BER plotted against the SNR for the proposed LLR-and SNR-based HDAF schemes and AF and ADF protocols.…”

“…BER performance is also plotted against the SNR, for the proposed scheme against other hybrid schemes [6,9,11] for a symmetric relay positioning, with = = 0.5 in Figure 3. The proposed LLR-based HDAF scheme outperforms all the others, including the SNR-based one.…”

“…In (1) and (2), the fading channel magnitudes, received signals, and additive white Gaussian noise (AWGN) with variance 0 are, respectively, denoted by ℎ , , and with ∈ { , , } and channel mean power Ω , where ℎ ∼ CN(0, Ω ) denotes the complex Gaussian random variable with zero-mean and variance Ω and ∼ CN(0, 0 ) are statistically independent. For the AF mode, the amplifying factor is chosen as [6]…”

“…Hybrid relaying schemes that switch between AF and FDF protocols were tackled in [6][7][8]. In [6,7], the authors provide simulations for a relaying system that allows to toggle between FDF, AF, and no-send protocols by comparing either the measured SNR or the calculated LLR of the received signal at with predefined thresholds.…”

“…Hybrid relaying schemes that switch between AF and FDF protocols were tackled in [6][7][8]. In [6,7], the authors provide simulations for a relaying system that allows to toggle between FDF, AF, and no-send protocols by comparing either the measured SNR or the calculated LLR of the received signal at with predefined thresholds. In [8], a closed-form expression is provided for the proposed relaying scheme, which allows to perform soft decoding and then forwards the reliability information at the output of its decoder to .…”