基于多载波的宽带无线接入策略的研究  

An access strategy research based on multicarrier communications for wideband wireless system

作　　者：马欣昕[1] 尹长川[1] 乐光新[1] 

机构地区：[1]北京邮电大学数字通信与信息网络实验室,北京100876

出　　处：《电路与系统学报》2005年第2期121-125,共5页Journal of Circuits and Systems

基　　金：国家自然科学基金资助项目(60172052);国家自然科学基金重大研究项目(90104018);863资助项目(2003AA12331004)

摘　　要：呼叫接入控制是无线通信中保证用户服务质量的关键技术之一。本文提出了一种在多业务环境下,基于多载波通信的优先强占接入策略:当剩余无线资源不能接纳实时业务的呼叫时,实时业务呼叫强占部分非实时业务占用的子载波来保证实时业务的接入,与此同时增加了非实时业务的传输时延。本文通过二维Markov链模型对系统进行了建模和性能参数(呼叫阻塞概率及系统频带利用率)的求解。通过与保护信道策略和无优先策略的比较可以看到:优先强占策略将接入控制和服务质量保证有机地结合在一起,既保证了用户的QoS,又大大降低了系统中的实时业务用户的呼叫阻塞概率,提高了系统资源的利用率。Call admission control (CAC) plays a significant role in providing the desired quality of service in wireless networks. In this paper, we propose an access strategy with preemptive priority in multicarrier cellular system for integrated call services. A real-time service call has the right to preempt part of non-real-time service call’s subcarriers in the preemptive priority access strategy if no enough free subcarriers are available, while the preempted non-real-time service call just adds its transmission delay. The system is modeled using a two-dimensional Markov chain and a numerical analysis is presented to estimate blocking probabilities of real-time service calls and non-real-time service calls, and the frequency utilization. It can be seen through comparison with the guard channel scheme and non-priority scheme that the proposed scheme improves the system performance.

关 键 词：多载波通信系统 接入控制 优先强占策略 

分 类 号：TN929.5[电子电信—通信与信息系统]