Optimal Relay Placement in Cellular Networks

Mattia Minelli (1, 2, 3) , Maode Ma (1) , Marceau Coupechoux (2, 3) , Jean-Marc Kélif (4) , Marc Sigelle (5) , Philippe Godlewski (2, 3)

1 NTU - Nanayang Technological University
2 RMS - Réseaux, Mobilité et Services
3 INFRES - Département Informatique et Réseaux
4 Orange Labs [Lannion]
5 LTCI - Laboratoire Traitement et Communication de l'Information

In this paper, we address the problem of optimally placing relay nodes in a cellular network with the aim of maximizing cell capacity. In order to accurately model interference, we use a dynamic framework, in which users arrive at random time instants and locations, download a file and leave the system. A fixed point equation is solved to account for the interactions between stations. We also propose an extension of a fluid model to relay based cellular networks. This allows us to obtain quick approximations of the Signal to Interference plus Noise Ratio (SINR) that are very close to 3GPP LTE-A guideline results in terms of SINR distribution.We then use these formulas to develop a dedicated Simulated Annealing (SA) algorithm, which adapts dynamically the temperature to energy variations and uses a combination of coarse and fine grids to accelerate the search for an optimized solution. Simulations results are provided for both in-band and out-of-band relays. They show how relays should be placed in a cell in order to increase the capacity in case of uniform and non-uniform traffic. The crucial impact of the backhaul link is analyzed for in-band relays. Insights are given on the influence of shadowing.

Domains: Computer Science [cs]; Networking and Internet Architecture [cs.NI]

Mattia Minelli, Maode Ma, Marceau Coupechoux, Jean-Marc Kélif, Marc Sigelle, et al.. Optimal Relay Placement in Cellular Networks. IEEE Transactions on Wireless Communications, 2014, 13 (2), pp.998-1009. ⟨10.1109/TWC.2013.010214.130814⟩. ⟨hal-00958679⟩