摘要:In this paper, we present a novel grouped OFDM-IDMA based downlink transmission scheme for femtocell networks. To avoid the cross-tier interference, we assign the femto users and marco users into different subcarrier groups for transmission. IDMA is used to mitigate the co-tier interference within the same group of users. We give the detailed system model as well as the transceiver structure of the proposed scheme. With the notion of SNR evolution function, we investigate the performance of the proposed scheme in terms of spectral efficiency and bit error rate (BER). Both theoretical analysis and simulations indicate that with the assistance of femtocell and grouping, the proposed scheme achieves better performance compared with the traditional OFDM-IDMA systems, while at the same time maintains an even lower complexity at the user terminal than the latter.