摘要
In order to achieve higher system energy efficiency （EE）,a new coordinated multipoint （CoMP）-transmission-based scheme selection energy saving （CTSES）algorithm is proposed for downlink homogeneous cellular networks.The problem is formulated as an optimization of maximizing system EE,under the constraints of the data rate requirement and the maximum transmit power.The problem is decomposed into power allocation and alternative scheme selection problems.Optimal power allocation is calculated for CoMP-JT （joint transmission）and CoMP-CS （coordinated scheduling） transmissions,and the scheme with higher EE is chosen. Since the optimal problem is a nonlinear fractional optimization problem for both CoMP transmission schemes, the problem is transformed into an equivalent problem using the parametric method. The optimal transmit power and optimal EE are obtained by an iteration algorithm in CoMP-JT and CoMP-CS schemes.Simulation results show that the proposed algorithm offers obvious energy-saving potential and outperforms the fixed CoMP transmission scheme.Under the condition of the same maximum transmit power limit,the empirical regularity of user distribution for scheme choice is presented, and using this regularity, the computational complexity can be reduced.
为了有效提升系统能量效率,提出下行同构网络中基于多点协作传输模式选择的节能算法.在考虑用户速率需求和系统发射功率限制条件前提下构建以最大化系统能效为目标函数的最优化问题.将目标问题分解成功率优化和模式选择2个子问题:首先计算CoMP-JT和CoMP-CS传输模式下的功率分配矩阵,然后选择能量效率较高的模式作为当前的传输模式.功率优化子问题是非线性分数优化问题,运用参数化方法将其转化为等效凸问题,在CoMP-JT和CoMP-CS下分别通过迭代算法求解最优功率和能效.仿真结果证实了所提方案具有明显的节能潜力,其系统能效优于固定CoMP模式.此外,还总结了相同最大发射功率限制条件下的模式选择规律,运用该规律可大大减少此类场景下的计算复杂度.
基金
The National Science and Technology Major Project(No.2013ZX03001032-004)
the National High Technology Research and Development Program of China(863 Program)(No.2014AA01A702)
Jiangsu Province Science and Technology Support Program(No.BE2012165)
Foundation of Huawei Corp.Ltd
