A study on an ANC system using narrow-band signals

Filtered-x LMS algorithm and its relatives are the most popular control algorithms for ANC, because of their simplicity and practical performance. In these algorithms, the input signal to the algorithms is the signal filtered by the plant model. As well known, this causes two major problems, i.e., large computational burden and the delay of the signal path. We have proposed a new method without using the plant model to overcome the above problems for specific applications such as ventilation equipment. In this article, the relation between bandwidth of the reference signal and the order of adaptive filters is verified. It's also shown that proposed algorithm performs almost the same as MELMS (extended algorithm of filtered-x LMS for multichannel case) with much less computational load.