Bursty Wideband Relay Networks

In wireless networks, the use of cooperation among nodes can significantly improve capacity and robustness to fading. However, many cooperation techniques have been developed for operation in narrowband systems for high signal-to-noise ratio (SNR) applications. It is important to study how relay networks perform in a wideband regime, where the available degrees of freedom is large and the resulting SNR per degree of freedom is small. In this paper, taking into account wideband transmissions with fixed power (Wrarr infin), we investigate the achievable rates and scaling laws of bursty amplify-and-forward relay networks in the wideband regime. Specifically, our results allow us to understand the effect of different system parameters on the achievable rates and scaling laws in the wideband regime, and highlight the role of bursty transmissions in this regime. We identify four scaling regimes that depend on the growth of the number of relay nodes and the increase of burstiness relative to the SNR. These results can serve as design guidelines to indicate when bursty transmissions are most useful.