Magnetic resonance imaging (MRI) scanners are used to support the diagnosis of medical conditions. However, the noise generated during MRI scanning, so called the MR-noise, is large and harsh to the patients. To reduce the MR-noise, the active noise control (ANC) system based on the simplified period aware linear prediction (SPALP) method has been proposed. The MR-noise is a periodic signal, therefore this method can reduce the MR-noise by linear prediction method using time-delayed signal of the MR-noise. However, the convergence speed is slow in this method. This is because the noise control filter is updated by the filtered-x normalized least mean square (FxNLMS) algorithm whose step size parameter cannot be set to large. To solve this problem, we propose SPALP-based ANC system combined with the modified error method where the noise control filter can be updated by the NLMS algorithm. In the proposed method, the noise control filter is updated by the NLMS algorithm by updating the noise control filter and generating the noise control signal independently. From the simulation results, the proposed method converges faster than the conventional method with the same noise reduction amount.
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