As the sampling rates of the inner loop and the outer loop of the target tracking control system are different,a typical digital multi-rate control system was formed.If the traditional single-rate design method was ap...As the sampling rates of the inner loop and the outer loop of the target tracking control system are different,a typical digital multi-rate control system was formed.If the traditional single-rate design method was applied,the low sampling rate loop will seriously impact the dynamical characteristic of the system.After analyzing and calculating the impact law of the low sampling rate loop to the bandwidth and the stability of the tracking system,a kind of multi-rate control system design method was introduced.Corresponding to the different sampling rates of the inner loop and the outer loop,the multi-rate control strategy was constituted by a high sampling rate sub-controller and a low sampling rate sub-controller.The two sub-controllers were designed separately and connected by means of the sampling rate converter.The low sampling rate controller determined the response rapidity of the system,while the high sampling rate controller applied additionally effective control outputs to the system during a sampling interval of the low sampling rate controller.With the introduced high and low sampling rates sub-controllers,the tracking control system can achieve the same performance as a single-rate controller with high sampling rate,yet it works under a much lower sampling rate.The simulation and experimental results show the effectiveness of the introduced multi-rate control design method.It reduces the settling time by 5 times and the over shoot by 4 times compared with the PID control.展开更多
单载波码分与频分多址(SC-CFDMA,single carrier code and frequency division multiple access)体制要求符号定时精确至码片级,同步难度高于普通体制。为此提出一种多速率星地闭环同步方法,通过适当提升部分环路元件的控制速率,在环路...单载波码分与频分多址(SC-CFDMA,single carrier code and frequency division multiple access)体制要求符号定时精确至码片级,同步难度高于普通体制。为此提出一种多速率星地闭环同步方法,通过适当提升部分环路元件的控制速率,在环路非采样点上延续闭环控制,从而提高对用户运动速度的适应能力。推导了控制速率提升后相关元件及环路的状态空间方程,进行了Matlab软件仿真,结果表明,即使在高轨卫星通信场景下,所提方法也能将多个超音速用户之间的SC-CFDMA上行符号定时偏差同步至码片宽度内,保证链路畅通。展开更多
基金Project(51105372) supported by the National Natural Science Foundation of ChinaProject(JC12-03-01) supported by the Research Plan of National University of Defense Technology,China
文摘As the sampling rates of the inner loop and the outer loop of the target tracking control system are different,a typical digital multi-rate control system was formed.If the traditional single-rate design method was applied,the low sampling rate loop will seriously impact the dynamical characteristic of the system.After analyzing and calculating the impact law of the low sampling rate loop to the bandwidth and the stability of the tracking system,a kind of multi-rate control system design method was introduced.Corresponding to the different sampling rates of the inner loop and the outer loop,the multi-rate control strategy was constituted by a high sampling rate sub-controller and a low sampling rate sub-controller.The two sub-controllers were designed separately and connected by means of the sampling rate converter.The low sampling rate controller determined the response rapidity of the system,while the high sampling rate controller applied additionally effective control outputs to the system during a sampling interval of the low sampling rate controller.With the introduced high and low sampling rates sub-controllers,the tracking control system can achieve the same performance as a single-rate controller with high sampling rate,yet it works under a much lower sampling rate.The simulation and experimental results show the effectiveness of the introduced multi-rate control design method.It reduces the settling time by 5 times and the over shoot by 4 times compared with the PID control.
文摘单载波码分与频分多址(SC-CFDMA,single carrier code and frequency division multiple access)体制要求符号定时精确至码片级,同步难度高于普通体制。为此提出一种多速率星地闭环同步方法,通过适当提升部分环路元件的控制速率,在环路非采样点上延续闭环控制,从而提高对用户运动速度的适应能力。推导了控制速率提升后相关元件及环路的状态空间方程,进行了Matlab软件仿真,结果表明,即使在高轨卫星通信场景下,所提方法也能将多个超音速用户之间的SC-CFDMA上行符号定时偏差同步至码片宽度内,保证链路畅通。
