编解码和时延约束下的网络化控制系统最优跟踪性能

本文研究了具有丢包、时延、编解码等通信资源受限下多输入多输出离散时间网络控制系统的最优跟踪性能. 基于频域方法, 采用二元随机过程来模拟数据包丢失, 并假设信道噪声是加性高斯白噪声(AWGN), 推导了在丢包、信道噪声、时延和编解码影响下的跟踪性能极限. 采用单参数补偿器(SDOF), 利用互质分解、Youla参数化等工具得到了编解码和时延约束下的网络控制系统最优跟踪性能的显式表达式. 结果表明, 跟踪性能与对象的固有特性(非最小相位零点与不稳定极点的位置和方向)、时延、丢包率和AWGN 功率谱密度密切相关.

Optimal tracking performance of networked control systems with encoding-decoding and time-delay constraints

The optimal tracking performance of multi-input multi-output (MIMO) discrete-time networked control systems (NCSs) under communication constraints such as packet loss, time-delay, encoding-decoding is studied in this paper. Based on the frequency-domain method, and by modeling packet loss as a binary random process and assuming that channel noise is additive white Gaussian noise (AWGN). The tracking performance limitations are derived. Using a single-degree-of-freedom (SDOF) compensator, an explicit expression for the optimal tracking performance of NCSs under encoding-decoding and time-delay constraints is obtained by means of techniques such as coprime decomposition and Youla parameterization. It is shown that the tracking performance has a close relation with the intrinsic characteristic of the plant such as locations and directions of nonminimum phase zeros and unstables poles, as well as the time-delay, packet loss rate and power spectral density of AWGN.