摘要
IEEE802.16标准具有面向连接的特性,能够为每个连接提供QoS保证。标准定义了QoS架构中BS与SS间交换信息的信令机制,但是并没有规定上行带宽分配的调度算法,而这正是目前802.16领域研究的热点。对于VoIP、流媒体等实时业务来说,其对延迟和延迟抖动非常敏感。针对这一情况,本文提出了一种调度算法,利用自适应编码和调制技术,通过动态变化调制和编码方式,以牺牲一定的传输速率为代价来保证链路的稳定工作。即使在无线网络状态不佳的情况下,连接的QoS需求也能得到保证,从而改善了实时业务的运行状况。
IEEE 802.16 has feature of connection-oriented, which can provide QoS guarantee for each connection. The standard defines the signaling mechanism for exchanging information between BS and SS in QoS architecture while it does not define the scheduling algorithm for uplink bandwidth allocation, so it has been the hot point for researching on IEEE 802. 16. For real time service such as VolP and flow media, it is very sensitive on delay and delay jitter. Considering this situation, this paper presents a scheduling algorithm utilizing adaptive data encoding and modulation technology. The stability of link transmission is guaranteed at the cost of lower the transmission rate by dynarnically adjusting modulation and coding settings. Even if in the bad condition of wireless link, the QoS of connection can still be guaranteed, therefore it improve the performance of real time service.
出处
《电子测量技术》
2007年第10期103-106,共4页
Electronic Measurement Technology
