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arXiv · 0908.0856

Outage Capacity of Incremental Relaying at Low Signal-to-Noise Ratios

Tobias Renk·Holger Jaekel·Friedrich K. Jondral·Deniz Gunduz·Andrea Goldsmith
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Abstract

We present the ε-outage capacity of incremental relaying at low signal-to-noise ratios (SNR) in a wireless cooperative network with slow Rayleigh fading channels. The relay performs decode-and-forward and repetition coding is employed in the network, which is optimal in the low SNR regime. We derive an expression on the optimal relay location that maximizes the ε-outage capacity. It is shown that this location is independent of the outage probability and SNR but only depends on the channel conditions represented by a path-loss factor. We compare our results to the ε-outage capacity of the cut-set bound and demonstrate that the ratio between the ε-outage capacity of incremental relaying and the cut-set bound lies within 1/\sqrt{2} and 1. Furthermore, we derive lower bounds on the ε-outage capacity for the case of K relays.

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Tobias Renk, Holger Jaekel, Friedrich K. Jondral, Deniz Gunduz, Andrea Goldsmith. 2009-08-06. Outage Capacity of Incremental Relaying at Low Signal-to-Noise Ratios. https://arxiv.org/abs/0908.0856

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