异构无线系统中一种改进的呼叫准入方案

An Improved Call Admission Control Scheme in Heterogeneous Wireless Networks

针对异构无线系统中上、下行业务需求不平衡引起的拥塞现象,提出了一种改进的呼叫准入方案。首先给出接入倾向度的概念,在接入时考虑用户的实际接入需求,并进一步提出了基于接入倾向度的呼叫准入改进方案,最后利用无差别曲线的方法确定接入倾向度的选择。仿真结果表明,改进后的方案在系统性能与用户公平性之间做到了较好折衷,具有较大的实用价值。

An improved Call Admission Control（CAC） scheme is proposed to avoid the congestion due to the asymmetry of uplink and downlink service resource requirements.This scheme first proposes Access Preference Degree（APD）,which is used to consider the actual access demand of users.Then an improved CAC scheme based on APD is proposed.Finally,indifference curve is used to determine APD value.Numerical results demonstrate that the proposed scheme achieves a good tradeoff between system performance and user fairness,and it has preferable application value.