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Development of Engine Exhaust Active Noise Control System

In order to enhance the capacity of elimination of engine exhaust low frequency noise, a set of engine exhaust active noise control system was developed. The system was developed by using MC9S12XS128 MCU, and it is based on the theory of sound wave interference. The system can realize the voice signal acquisition, reverse phase processing and output, and can eliminate engine exhaust low frequency noise. Experimental results showed that the system has good silencing effects on the engine exhaust noise under the steady state.