An energy efficient downlink resource allocation strategy for multiuser CP-OFDM and FBMC systems

We address in this paper the quality of service (QoS) constrained radio resource allocation problem at the downlink of multiuser multicarrier systems. Based on the trade-off between energy consumption and transmit power within a cross physical and link layer system model, which jointly considers power allocation, adaptive modulation and coding and ARQ/HARQ retransmission protocols, a transmit power constrained energy minimization problem is formulated. The proposed suboptimal resource allocation algorithm is applied to both cyclic prefix based OFDM (CP-OFDM) and filter bank based multicarrier (FBMC) systems. Due to the absence of CP and the better spectral shaping of subcarriers, the FBMC system can exploit more subcarriers and symbols for data transmission and is less sensitive to carrier frequency offset (CFO), as compared to the CP-OFDM system. These advantages further lead to better QoS provisioning and higher energy efficiency of the former, which are demonstrated by simulation results.