To improve the total throughput of the uplink orthogonal frequency division multiple access system,a low complexity hybrid power distribution(HPD)combined with subcarrier allocation scheme is proposed.For the fairness...To improve the total throughput of the uplink orthogonal frequency division multiple access system,a low complexity hybrid power distribution(HPD)combined with subcarrier allocation scheme is proposed.For the fairness mechanism for the subcarrier,the inter-cell interference is first analyzed to calculate the capacity of the multi-cell.The user selects the subcarrier with the largest channel gain.Based on the above subcarrier allocation scheme,a new kind of HPD scheme is proposed,which adopts the waterfilling-power-distributed scheme and the equal-power-distributed scheme in the cell-boundary and the cellcenter,respectively.Simulation results show that compared with the waterfilling-power-distributed scheme in the whole cell,the proposed HPD scheme decreases the system complexity significantly,meanwhile its capacity is 2%higher than that of the equal-powerdistributed scheme over the same subcarrier allocation.展开更多
Several fragments of Comet Hyakutake were observed in March and April of 1996. This leads to the impression that the splitting of Comet Hyakutake on a small scale occurred frequently. Data analysis points to a rotatio...Several fragments of Comet Hyakutake were observed in March and April of 1996. This leads to the impression that the splitting of Comet Hyakutake on a small scale occurred frequently. Data analysis points to a rotation period of about 6 2 h if the fragments of April 11 are the condensations within a jet.展开更多
基金supported by the National Basic Research Programof China(973 Program)(2007CB310601)the Major Science-Technology Project of Next Generation Wireless Mobile Communication Network(2009ZX03004-001)
文摘To improve the total throughput of the uplink orthogonal frequency division multiple access system,a low complexity hybrid power distribution(HPD)combined with subcarrier allocation scheme is proposed.For the fairness mechanism for the subcarrier,the inter-cell interference is first analyzed to calculate the capacity of the multi-cell.The user selects the subcarrier with the largest channel gain.Based on the above subcarrier allocation scheme,a new kind of HPD scheme is proposed,which adopts the waterfilling-power-distributed scheme and the equal-power-distributed scheme in the cell-boundary and the cellcenter,respectively.Simulation results show that compared with the waterfilling-power-distributed scheme in the whole cell,the proposed HPD scheme decreases the system complexity significantly,meanwhile its capacity is 2%higher than that of the equal-powerdistributed scheme over the same subcarrier allocation.
文摘Several fragments of Comet Hyakutake were observed in March and April of 1996. This leads to the impression that the splitting of Comet Hyakutake on a small scale occurred frequently. Data analysis points to a rotation period of about 6 2 h if the fragments of April 11 are the condensations within a jet.