• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.36 no.11
• /
• pp.819-825
• /
• 1987

The ALE problem, which tries to recover a sinusoidal signal corrupted by noise, has been solved using FIR filters. Recently several methods have been proposed using a norch filter of IIR type. In this study, the notch filter was represented with a parameter and auxiliary signals were generated by using an adaptive observer. A simple method is proposed to estimate the parameter. This method is tested under various circumstances by changing the input frequency, S/N ratio, and the type of the noise. The simulation shows that this method gives much better results than the other known methods with respect to the input S/N ratio and converging times. This method is simple and does not require much conputation, so it can be easily implemented in real time applications.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.19 no.10
• /
• pp.2053-2063
• /
• 1994

Recently, there has been much interest in the terrestrial broadcasting of the HDTV signal. However, in the Simulcast where the NTSC and HDTV signal are transmitted using the same channel, the cochannel interference occurs which degrade the transmission performance. Recently, the GA(Grand Alliance) proposed the cochannel interference rejection system which use comb filter. However, this method shows poor performance for the NTSC carrier variation [7]. In this paper we propose a novel NTSC cochannel interference rejection system which shows improved performance for the NTSC carrier variation. In the proposed scheme, the adaptive notch filter is employed along with adaptive channel equalizer. In this paper, we also present some analytical results on the NTSC rejection performance of the GA and proposed scheme. Computer simulation results reveal that the proposed scheme outperforms order outperforms order of 10 in the BER(bit error rate) sense for the normal condition.

• Proceedings of the KIEE Conference
• /
• 1993.07a
• /
• pp.456-459
• /
• 1993

A new filter-bank is proposed in order to track center frequency of narrow bard signal. The filter-bark proposed here has a laster and a slave filter bark. The two barks are connected in series-parallel. The master filter bank which is made of traditional filter bank detects the center frequency roughly. And the performance for tracking center frequency is greatly improved by the slave filter bank which is based or energy-difference estimator. Computer simulations show that it achieves a good tracking accuracy.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.7A
• /
• pp.651-658
• /
• 2002

Although least mean square(LMS) algorithm is known to one of the most popular algorithm in adaptive signal processing because of the simplicity and the small computation, the choice of the step size reflects a tradeoff between the misadjustment and the speed of adaptation. In this paper, we present a new variable step size LMS algorithm, so-called ECLMS(Estimated correlation LMS), using the correlation between reference input and error signal of adaptive filter. The proposed algorithm updates each weight of filter by different step size at same sample time. We applied this algorithm to adaptive multiple-notch filter. Simulation results are presented to compare the performance of the proposed algorithm with the usual LMS algorithm and another variable step algorithm.

• Progress in Superconductivity
• /
• v.4 no.1
• /
• pp.53-58
• /
• 2002

Noise from electronic instrumentation is invariably present in biomedical signals, although the art of instrumentation design is such that this noise source may be negligible. And sometimes signals of interest are contaminated or degraded by signals of similar type from another source. Biomedical signals are omni-presently contaminated by these background noises that span nearly all frequency bandwidths. In the magneto-cardiogram (MCG), several digital filters have been designed for the elimination of the power-line interference, broadband white noise, surrounding magnetic noise, and baseline wondering. In addition to the introduced FIR filter, notch, adaptive filter using the least mean square (LMS) algorithm, and recurrent neural network (RNN) filter, a new filtering method for effective noise canceling in MCG signals is proposed in this paper, which is realized by the wavelet packets. The experimental results show that the proposed filter using wavelet packet performs efficiently with respect to noise rejection. To verify this, two characteristics were analyzed and compared with LMS adaptive filter, SNR of filtered signal and attractor pattern using the nonlinear dynamics.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.52 no.10
• /
• pp.611-617
• /
• 2003

A mechanical or electrical stimulation to the mandibular symphysis during a maximal voluntary clenching of the teeth always produces a jaw jerk followed by a silent period (transient stops) in the masseteric EMG (electromyogram). Generally, a mechanical stimulation is followed by a single silent period, and an electrical stimulation is followed by multiple silent periods. In this paper, we propose a new algorithm for determining the duration of the masseter silent period. The decision approach in essentially based upon a segmentation algorithm consisted of variance filter, median filter and gaussian filter. The new adaptive digital notch filter using R-CLMS(reverse constrained least mean-squared) algorithm is proposed for the elimination of powerline(60Hz) noise. At the same time, we design a real time measurement system for the EMG silent period under Window base.

• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 2006.07a
• /
• pp.433-433
• /
• 2006

• 제어로봇시스템학회:학술대회논문집
• /
• 1992.10a
• /
• pp.776-779
• /
• 1992

This paper describes the auto-depth control system with depth control tank for low speed submersible vehicle that can be used for both near surface and deeply submerged keeping operations. The PDA control algorithm is used to design controller and adaptive notch filter is designed to eliminate the dominant frequency of seaway. The computer simulations demonstrate the excellent depth keeping performance of the controller under seaway effects.

• Journal of Advanced Navigation Technology
• /
• v.14 no.5
• /
• pp.745-751
• /
• 2010

In this paper, the proposed a narrowband interference cancellation techniques for the frequence sharing of Ultra wideband Impulse Radio communication system and narrowband communication system. In this system, the narrowband communication signals can cause intolerant interferences to Impulse Radio signals. In this paper, Ultra wideband Impulse Radio system have been analyzed in AWGN, MAI and NI(Narrowband Interference) environment. Also, performance improvement has been obtained by adopting an adaptive notch filtering scheme using Complex Filter Bank and CCI canceller. The results show that there is a substantial enhancement in performance by employing the adaptive notch filtering and/or CCI canceller.

• Proceedings of the KIEE Conference
• /
• 2005.07d
• /
• pp.2477-2479
• /
• 2005

A robust bending frequency tracker is proposed to design the adaptive notch filter which removes the time-varying missile structural modes from the sensor measurements. To do this, the state-space form of a bending frequency model is derived under the assumption that the bending signal could be described as the lightly damped sinusoid. Since the resultant bending frequency model contains the parametric uncertainties in the measurement matrix, the design problem of bending frequency tracker is tackled by applying the robust Kalman filter to the model. This technique could be easily expanded to the multiple frequencies case because it newly illuminates the bending frequency tracking problem in view of general state estimation.