Performance Analysis of Telecommunication System with Feedforward Control Mechanism

摘要

The goal of this paper is to analyze processes in an Internet node queueing system with local feedforward control. The proposed analysis method based on Moore and Mealy automata is much simpler and universal than Markov processes applied previously by authors to the analysis of such queueing systems [1, 2, 3]. Feedback and feedforward control is typically used in the telecommunication systems which have time varying transmission parameters. A rich literature exists in the area of data packets transmission process control systems. The majority of them analyze the feedback or feedforward control mechanism to regulate variable data packets transmission parameters, to avoid congestion and overdone delay, and to achieve high data transmission link utilization. The new type of the control system over the Internet allows remote monitoring and control of process plants using for control systems feedback and feedforward actions [8]. The feedforward and backward multirate control mechanism for IP transport network is applied to avoid data link congestion and data packet losses [11]. Two stages bit rate control mechanism must achieve that the originating part sends data at the maximum possible rate to the link [11]. Control algorithms to dynamically adjust bit rate of sender are design to guarantee stable performance measures of data transmission network based on continuous or discrete time feedback [9]. A two-level hierarchy is used for the Internet based control systems with two compensators located at the feedback channel that results the multirate control scheme efficiently reduce the effect of Internet time delay [7, 8]. One possible way to solve problem of network congestion and guarantee the quality of service is to use the feedback control mechanism to adapt the sender output bit rate depending on the transmission link state [6, 10]. Implementation of Moore and Mealy automata in of one channel queueing system simulation allows investigation of processes in a complex system such as telecommunication network [5].