基于效用最大化的DVB-RCS跨层动态带宽分配

Utility Maximization-Based DVB-RCS Cross-Layer Dynamic Bandwidth Allocation

针对已有效用函数的动态带宽分配(DBA)模型未考虑物理层信道条件来完成DVB-RCS(Digital Vid-eo Broadcasting-Return Channel via Satellite)卫星通信网的DBA,从而导致吞吐量下降这一缺点,本文提出一种跨层效用函数DBA模型。该模型建立基于信道条件的效用函数,以实现效用最大化的DBA,因此转化为非线性整数规划问题的求解。同时提出一种基于等效用增量的Greedy迭代算法求解该问题,求出效用最大化的带宽分配向量,降低了传统Greedy算法的计算量。仿真结果表明该模型在保证回传信道卫星终端(Return Channel Satellite Termi-nal,RCST)用户公平性的同时,提升DVB-RCS卫星通信网的吞吐量。

The existing dynamic bandwidth allocation（DBA） model based on utility function is unable to take account of channel condition in physical layer during implementing DBA in digital video broadcasting-return channel via satellite（DVB-RCS） satellite communication network,so that it brings in the disadvantage of throughput reduction.To tackle above weakness,a DBA model based on cross-layer utility function is proposed.This model is used to build channel condition-based utility function to realize a DBA of utility maximization,so that this DBA is transferred into a nonlinear integer programming problem.An equal utility increment-based Greedy iterative algorithm is also proposed to attain the bandwidth allocation vector with utility maximization,thus reducing computational effort in traditional Greedy algorithm.Simulation results show this model raises throughput within DVB-RCS satellite network and the fairness among return channel satellite terminal（RCST） is guarranteed.