非最小相位(NMP)問題通常造成傳統主動噪音控制法失效。本研究提出兩種以H2及H(下標 ∞)前饋模式匹配原理為基礎之控制法。這些方法能有效解決因第二控制路徑NMP問題所造成的逆場不穩定的困難。數值模擬結果顯示此二法比傳統方法較能抑制管路中之寬頻隨機噪音。
Nonminimum (NMP) phase problem is in general the cause of failure of the conventional active noise control approaches in suppressing random noises. This study proposes two novel techniques based on feedforward H2 and H(subscript ∞) optimal model matching principle. These methods effectively overcome the unstable inverse plant problem resulted from the inherent nonminimum phase property of the secondary path. The numerical results obtained from a broadband random noise and an impulse in a duct show significant attenuation over conventional methods.