Digital signal processor implementation of active noise control systems for broadband noise cancellation in engine exhaust systems

This paper describes the principle and application of broadband active noise control (ANC) for engine exhaust systems using a spatially feedforward structure. The algorithm of the proposed controller is obtained from previous work by Roure (1985), Munjal and Eriksson (1988), Hong and Bernstein (1998), and there exist some conclusions for this structure. The self-adaptive broadband controller is discussed and implemented on a digital signal processor (DSP), using finite impulse response (FIR) and infinite impulse response (IIR) filters. Experiments were carried out to evaluate the proposed system for reducing the noise under different engine operating conditions. The experimental results indicate that the ANC system is effective in reducing the broadband noise for engine exhaust systems using the spatially feedforward structure.