实时多媒体流控中的DMC时滞补偿器设计

DESIGN OF DMC TIME-DELAY COMPENSATOR FOR FLOW CONTROL IN REAL-TIME MULTIMEDIA COMMUNICATION

网络传输的抖动影响了VOD的播放质量。采用反馈控制机制进行实时多媒体流量控制是一种有效解决方法,但因实时多媒体流量控制及性能要求的特殊性,仅采用传统的反馈控制技术难以消除这一缺点。针对此问题,在速率反馈控制理论框架的基础上,将先进控制理论中的一些思想方法运用到VOD的流量控制中,采用了DMC控制器进行反馈控制。由实验结果表明,该方法具有一定的有效性,克服由于扰动和传输延迟带来的不利影响,提高了播放质量。

Jitter in network transmission impacts the play back quality of VOD. The feedback control mechanism for the real-time multimedia traffic control is an effective means to overcome this problem. Due to the particularity of real-time multimedia flow control and performance demand however, it is difficult to use conventional feedback control technology to achieve this. To solve the problem, on the basis of rate-feedback control theory framework, the thoughtway in advanced control theory is applied to traffic control in VOD, and DMC controller is adopted to carry out the feedback control. The experimental results show that this scheme presented in the paper is effective to some extent and can overcome the adverse effect caused by transmission delay and jitter. The play quality improved.