This paper investigates the resource allocation problem for the cluster-based cooperative multicast in orthogonal frequency division multiplexing (OFDM)-based cognitive radio (CR) systems. Aiming at maximizing the...This paper investigates the resource allocation problem for the cluster-based cooperative multicast in orthogonal frequency division multiplexing (OFDM)-based cognitive radio (CR) systems. Aiming at maximizing the system sum rate, an efficient clustering scheme is proposed. It begins with the clustering phase where secondary users (SUs) with good channel conditions are selected as cluster heads, while others decide to which cluster they belong. When the clusters are organized, it turns to a two-stage data transmission phase: in stage 1, the secondary' base station (BS) transmits data to the cluster heads; in stage 2, the cluster heads forward the received data to their cluster members. Based on this scheme, a joint subcarrier and power allocation algorithm is proposed. Simulation results show that the proposed scheme significantly outperforms the conventional multicast (CM) as well as the multiple description coding multicast 0VIDCM) in terms of the system sum rate.展开更多
In order to guarantee the wireless multicast throughput at a minimum cost, we propose a layered hypergraph high-dimension clustering algorithm (LayerHC) considering the channels and statistical locations of mobile mem...In order to guarantee the wireless multicast throughput at a minimum cost, we propose a layered hypergraph high-dimension clustering algorithm (LayerHC) considering the channels and statistical locations of mobile members. The algorithm can achieve a minimum multicast spanning tree to obtain a minimum number of relays and effective cooperative areas with low computational complexity.展开更多
基金supported by the National Basic Research Program of China (2009CB320401)the National Natural Science Foundation of China (61101117)+1 种基金National Key Scientific and Technological Project of China (2012ZX03004005002)Fundamental Research Funds for the Central Universities (BUPT2012RC0112)
文摘This paper investigates the resource allocation problem for the cluster-based cooperative multicast in orthogonal frequency division multiplexing (OFDM)-based cognitive radio (CR) systems. Aiming at maximizing the system sum rate, an efficient clustering scheme is proposed. It begins with the clustering phase where secondary users (SUs) with good channel conditions are selected as cluster heads, while others decide to which cluster they belong. When the clusters are organized, it turns to a two-stage data transmission phase: in stage 1, the secondary' base station (BS) transmits data to the cluster heads; in stage 2, the cluster heads forward the received data to their cluster members. Based on this scheme, a joint subcarrier and power allocation algorithm is proposed. Simulation results show that the proposed scheme significantly outperforms the conventional multicast (CM) as well as the multiple description coding multicast 0VIDCM) in terms of the system sum rate.
基金Acknowledgements This work was supported by Natural Science Foundation of Beijing under Grant No. 4102041.
文摘In order to guarantee the wireless multicast throughput at a minimum cost, we propose a layered hypergraph high-dimension clustering algorithm (LayerHC) considering the channels and statistical locations of mobile members. The algorithm can achieve a minimum multicast spanning tree to obtain a minimum number of relays and effective cooperative areas with low computational complexity.