ABSTRACT

The problems of noise cancelling systems are based on the specific characteristics of their sources. Therefore, the knowledge of each noise source should be represented prior to the excecution of the designed noise cancelling scheme. Since the noises emitted vary with the types of the passing vehicles, the scheme should be well adjusted automatically. The delay must be minimixed by managing the value of step size. Five representing types of noise producing vehicles (noise from: bus, truck, motocycle, car with diesel fuel, and car with gasoline) were always changing following the passing vehicle. The robust LMS (Least Mean Square) algorithm was applied first, then followed by modification LMS algorithm. The results show that LMS algorithm with two process, which is modification from adaptive LMS algorithm is the simplest and the best if it is applied in vehicle’s noise cancellation.