Ambulance Siren Noise Reduction using LMS and FXLMS Algorithms

Ambulance Siren Detector using FFT on dsPIC

The purpose of this study is to make software of equipment that detects siren sound of ambulance and to program it on a microcontroller in the equipment. By using two times FFT (Fast Fourier Transform) on detecting, the characteristics of the siren sound could be converted into numerical values. Siren sound was detected properly even under the Doppler effect. The proposed method could detect th...

Application of the Fxlms Algorithm in Active Noise Reduction

Application of the filtered-X LMS algorithm to adaptive/active noise cancelling in headsets or hearing protectors has been investigated. The speed of convergence and amount of obtainable noise reduction was investigated for different step-size parameters and FIR filter lengths. Simple models for the headphone transfer function and the sound transmission through the ear cups are applied. We have...

Experimental evaluation of leaky LMS algorithms for active noise reduction in communication headsets

Fast exact filtered-X LMS and LMS algorithms for multichannel active noise control

In some situations where active noise control could be used, the well-known multichannel version of the ltered-X LMS adaptive lter is too computationally-complex to implement. In this paper, we develop a fast, exact implementation of this multichannel system whose complexity is approximately O(2L) per lter channel, where L is the FIR lter length. In addition, we provide a computationally-e cien...

Fast implementations of the filtered-X LMS and LMS algorithms for multichannel active noise control

{ In some situations where active noise control could be used, the well-known multichannel version of the ltered{X LMS adaptive lter is too computationally-complex to implement. In this paper, we develop a fast, exact implementation of this adaptive lter for which the system's complexity scales according to the number of lter coeecients within the system. In addition, we extend computationally-...