Groupe d’études et de recherche en analyse des décisions

Resource Allocation and Base Station assignment for OFDMA cellular systems

Diego Enrique Perea-Vega

We consider an OFDMA system comprised of \(N\) Base Stations (BS) with downlink transmitting powers \(Pj (j=1..N)\), and \(M\) Service Stations (or users) with uplink transmitting powers \(Qi (i=1..M)\). In an ODFMA system, communication between BS and its assigned users is done by individually modulating and coding a set of Nc sub-carriers. Carriers are assigned to users according to the individual user data rate requirements. The problem addressed in this work is to assign sub-carriers and their corresponding powers (\(Pj\) for downlink and \(Qi\) for uplink) in such way that the total downlink power sum(\(Pj\)) (or sum(\(Qi\)) for the uplink) are minimized while data rate requirements are satisfied. In addition, the problem of optimally assigning (in the minimum total power sense) users to BS stations is addressed. The solution of this problem is of capital importance for the deployment of current OFDMA-based technologies like the metropolitan wireless network WiMAX.