Automatic Stabilization of an Adaptive Feedback Control for Noise Cancelling In-ear Headphones

作     者：Sven Hoeber Christian Pape Eduard Reithmeier 

作者机构：Institute of Measurement and Automatic Control Leibniz University Hanover Hanover 30167 Germany 

出 版 物：《Journal of Mechanics Engineering and Automation》 (机械工程与自动化（英文版）)

年 卷 期：2016年第6卷第7期

页      面：364-372页

学科分类：0711[理学-系统科学] 07[理学] 08[工学] 081101[工学-控制理论与控制工程] 0811[工学-控制科学与工程] 071102[理学-系统分析与集成] 081103[工学-系统工程] 

主　　题：Active noise cancellation feedback control stability analysis. 

摘      要：Headphones with an integrated active noise cancellation system have been increasingly introduced to the consumer market in recent years. When exposing the human ear to active noise sources in this striking distance, the ensuring of a safe sound pressure level is vital. In feedback systems, this is coupled with the stability of the closed control loop; stable controller design is thus essential. However, changes in the control path during run-time can cause the stable control system to become unstable, resulting in an overdrive of the speakers in the headphones. This paper proposes a method, which enables the real-time analysis of the current system state and if necessary stabilizes the closed loop while maintaining the active noise reduction. This is achieved by estimating and evaluating the open loop behavior with an adaptive filter and subsequently limiting the controller gain in respect to the stability margin.