A Call-Admission Control (CAC) Algorithm for Providing Guaranteed QoS in Cellular Networks
A Call-Admission Control (CAC) Algorithm for Providing Guaranteed QoS in Cellular Networks
复制标题
用于在蜂窝网络中提供有保证的 QoS 的呼叫准入控制 (CAC) 算法
DOI：
10.1023/a:1025361326776
复制
发表时间：
2003
影响因子：
2.5
通讯作者：
D. Sarkar
中科院分区：
文献类型：
--
作者：
Satya Kovvuri;Vijoy Pandey;D. Ghosal;B. Mukherjee;D. Sarkar
未来的宽带无线接入系统预计将集成各种类别的移动的终端（MT），每个类别具有不同类型的服务质量（QoS）要求。当无线网络上的负载高时，保证每类MT的QoS是一项具有挑战性的任务。本研究考虑了两类MT-异形MT和非异形或常规MT。假设分析的用户需要有保证的QoS。QoS的度量是被允许接入网络的呼叫被强制终止的概率。两个先前的切换优先级方案-（i）预请求方案和（ii）保护信道方案-减少切换失败（并因此强制终止）。在这项工作中，我们比较和对比这两种方案，通过广泛的模拟，我们发现，无论是保护信道，也没有信道预请求方案可以保证所需的QoS水平的剖析MT。然后，我们提出了一种新的呼叫准入控制（CAC）算法，可以保持任何期望的QoS水平，而成功的呼叫完成率是非常高的。在所提出的算法中，新的呼叫到达率估计不断，当估计的到达率高于一个预定的水平，一些新的呼叫被阻止，而不管信道的可用性。这个新呼叫预阻塞的目的是保持小区的观测到的新呼叫到达速率不超过预定速率。我们表明，所提出的方法可以保证任何所需的QoS水平的配置文件的用户。
Future broadband wireless access systems are expected to integrate various classes of mobile terminals (MTs), each class with a different type of quality of service (QoS) requirement. When the load on a wireless network is high, the guarantee of QoS for each class of MTs is a challenging task. This study considers two classes of MTs—profiled MTs and nonprofiled or regular MTs. It is assumed that profiled users require a guaranteed QoS. The measure of QoS is the probability of forced termination of a call that was allowed to access the network. Two previous handoff prioritization schemes—(i) prerequest scheme and (ii) guard channel scheme—decrease handoff failure (and hence forced termination). In this work, we compare and contrast both the schemes through extensive simulation and we find that neither guard channel nor channel prerequest scheme can guarantee a desired level of QoS for the profiled MTs. We then propose a novel call-admission control (CAC) algorithm that can maintain any desired level of QoS, while the successful call completion rate is very high. In the proposed algorithm, the new call arrival rate is estimated continuously, and when the estimated arrival rate is higher than a predetermined level, some new calls are blocked irrespective of the availability of channels. The objective of this new call preblocking is to maintain a cell's observed new call arrival rate at no more than the predetermined rate. We show that the proposed method can guarantee any desired level of QoS for profiled users.