Coordinated Multi-Point(CoMP) transmission is put forward in the Long Term Evolution-Advanced(LTE-A) system to improve both average and cell-edge throughput. In this paper, downlink CoMP(DL-CoMP) resource allocation scheme based on limited backhaul capacity is designed to take a tradeoff between system throughput and fairness. Resource allocation of proportional fairness based on querying table is proposed. It updates RB allocation matrix when center cell has completed resource allocation and delivers the matrix to adjacent cells for their own RB allocation. Furthermore, Water-Filling algorithm based on adaptive water level(AWF) is used for power allocation to boost system fairness. In this paper, performance of downlink CoMP based on limited backhaul capacity and single-point transmission is contrasted, and results indicate that CoMP dramatically enhances system throughput and spectral efficiency. Moreover, AWF power allocation scheme obtains higher system fairness than conventional Water-Filling(WF) algorithm, although it gets slightly lower system throughput. Finally, this paper discussed that the system performance is partially affected by the percentage of CoMP resource. Coordinated Multi-Point (CoMP) transmission is put forward in the Long Term Evolution-Advanced (LTE-A) system to improve both average and cell-edge throughput. In this paper, a downlink CoMP limited backhaul capacity is designed to take a tradeoff between system throughput and fairness. It is RB allocation matrix when center cell has completed resource allocation and delivers the matrix to adjacent cells for their own RB allocation, further, Water-Filling algorithm based on adaptive water level (AWF) is used for power allocation to boost system fairness. In this paper, performance of downlink CoMP based on limited backhaul capacity and single-point transmission is contrasted, and indicate that that CoMP dramatically enhances system throughput and spectral efficiency. Moreover, AWF power allocation scheme determines higher system fairness than conventional W Finally, this paper discusses that the system performance is partially affected by the percentage of the CoMP resource.