• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.2459-2462
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• 2003

In this paper, we Propose a wavelet based adaptive algorithm which improves the convergence speed and reduces computational complexity using the fast running FIR filtering efficiently. We compared the performance of the proposed algorithm with time and frequence domain adaptive algorithm using computer simulation of adaptive noise canceler based on synthesis speech.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.2427-2430
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• 2003

A uniformly sampled digital pulse-width modulation adopting a pre-compensation filter scheme for applications in high-resolution digital-to-analog data conversion is described. It is shown that linearization of the intrinsic distortion resulting in uniformly sampled pulse-width modulation can be achieved by using a non-integer delay digital filter embedded within a noise shaping re-quantizer.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(4)
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• pp.179-182
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• 2002

In this paper, we propose a wavelet based adaptive algorithm which improves the convergence speed and reduces computational complexity using the fast running FIR filtering efficiently We compared the performance of the proposed algorithm with time and frequence domain adaptive algorithm using computer simulation of adaptive noise canceler based on synthesis speech. As the result, the proposed algorithm is suitable for adaptive signal processing area using speech or acoustic field.

• 제어로봇시스템학회논문지
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• 제16권12호
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• pp.1143-1149
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• 2010

Because the noise is the main cause for decreasing the performance at speech recognition, the place or environment is very important in speech recognition. To improve the speech recognition performance in the real situations where various extraneous noises are abundant, a novel combination of FIR and Wiener filters is proposed and experimented. The combination resulted in improved accuracy and reduced processing time, enabling fast analysis and response in emergency situations. Usually, there are many dangerous situations in our city life, so for the smarter city it is necessary to detect many types of sound in various environment. Therefore this paper is about how to detect many types of sound in real city, especially on CCTV. This paper is for implementing the smarter city by detecting many types of sounds and filtering one of the emergency sound in this sound stream. And then it can be possible to handle with the emergency or dangerous situation.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.845-850
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• 2003

The scattered light pattern from a machined surface generally contains much information concerning the surface roughness. The light pattern can be acquired by optical system and analyzed by statistical method. This kind of surface roughness measurement system can be easily adopted on the machine measurement. But the fully assembled system is too complex to implement on small systems using micro-controller. This study proposes the idea of reducing the number of optical components by removing screen and examines image processing of a light pattern to minimize the negative result of incomplete optical system. And the Gaussian blur filtering is concluded to be the best method of proposed measurement system. Furthermore light intensity variation of image pattern can be treated as a signal, therefore FIR filtering gives the similar result of Gaussian blur effect.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.46-49
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• 2000

An iterative deblocking algorithm for DCT-compressed images using two-dimensional FIR filters adapted for local directionality of each block, is proposed. First, we introduce a set of simple lowpass filters, which are adapted for edges of different angles. In conventional deblocking methods based on lowpass-filtering and convex projections, a single filter is applied to a whole image. In the proposed method, on the other hand, a suitable filter is chosen out of the directional filters designed previously in every subimage (typically $8{\times}8$ block). Experimental results indicate that adaptive filtering improves PSNR at each iteration.

• 대한전기학회논문지:시스템및제어부문D
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• 제51권8호
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• pp.360-367
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• 2002

In this paper, genetic algorithm based adaptive image enhancement filtering scheme is proposed and Implemented on FPGA board. Conventional filtering methods require a priori noise information for image enhancement. In general, if a priori information of noise is not available, heuristic intuition or time consuming recursive calculations are required for image enhancement. Contrary to the conventional filtering methods, the proposed filter system can find optimal combination of filters as well as their sequent order and parameter values adaptively to unknown noise types using structured genetic algorithms. The proposed image enhancement filter system is mainly composed of two blocks. The first block consists of genetic algorithm part and fitness evaluation part. And the second block consists of four types of filters. The first block (genetic algorithms and fitness evaluation blocks) is implemented on host computer using C code, and the second block is implemented on re-configurabe FPGA board. For gray scale control, smoothing and deblurring, four types of filters(median filter, histogram equalization filter, local enhancement filter, and 2D FIR filter) are implemented on FPGA. For evaluation, three types of noises are used and experimental results show that the Proposed scheme can generate optimal set of filters adaptively without a pioi noise information.

• 대한전자공학회논문지
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• 제26권7호
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• pp.106-111
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• 1989

본 연구에서는 근신호로 부터 SMUAP의 패턴 분류를 위한 새로운 근신호처리 알고리듬을 제시하였다. 제안된 알고리듬은 spike 카운터를 이용한 의사결정 방법으로서 ISI의 조합 및 규칙성을 검사하고, 주파수 평면에서 SMUAP 파형을 정렬하였으며 FIR 필터링을 통하여 스파이크를 선정하였다. 실험결과 IBM PC/AT 상에서 $10{\sim}50%$ MVC에 대한 5초 동안의 침 전극으로 검출된 근신호로 부터 $5{\sim}9$개의 SMUAP를 분류하였으며 인식율은 55% 이상이었고 컴퓨터 수행시간은 2분이었다.

• 전자공학회논문지S
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• 제36S권3호
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• pp.106-115
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• 1999

본 연구에서는 충격잡음이 부가되는 비정상 신호 및 잡음 환경하에서 실시간 시지연 추정이 가능한 SLMPTDE와 ZFLMSTDE의 새로운 적응 시지연 추정 방법을 제안하였다. 본 연구에서 제안한 방법은 중간직교 척도를 바탕으로 임의의 SαS 확률과정에 강건하게 적용할 수 있도록 유도된 확률적 경사형적응 추정 알고리즘으로 구성되었으며, SαS 분포를 갖는 다양한 충격잡음을 대상으로 모의 실험하여 알고리즘의 통계적 수렴특성 및 우정 오차에 대해 분석하였으며, 기존의 LMSTDE 방법과 일정시지연의 경우와 시변시지연의 경우에 대해 실시간 시지연 추정능력을 비교, 분석하였다. 실험결과로부터, LMSTDE 방법은 α≥1.9인 가우시안 잡음에 대해서만 시지연 추정이 가능하였고 P=1로 설정한 SLMPTDE 방법은 1〈α≤2인 경우의 SαS 잡음에 대해 정확한 시지연 추정능력을 보였으며, ZFLMSTDE 방법은 0〈α≤2인 모든 경우의 잡음 환경에 대해 그 능력이 입증되었다.

• 한국컴퓨터정보학회논문지
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• 제17권2호
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• pp.113-118
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• 2012

본 연구에서는 IEEE 802.11 OFDM 수신기에 적용하기 위한 DDC(Digital Down Converter) 설계 방법에 대하여 연구하였다. 상용화 칩으로는 구현이 어려운 WiFi 응용서비스의 요구사항을 만족하기 위해서는 적절한 수신기 개발이 필요하다. OFDM 수신기에서 DDC는 AD 컨버터로부터 업 샘플링된 I/Q(Inphase/Quadrature) 신호를 수신하여 decimation을 위한 신호를 만들기 위해 CIC(Cascaded Integrator Comb) 필터블럭을 거쳐 다운 샘플링한 후 다시 이 신호를 보정하기 위한 FIR(Finite Impulse Response) 필터를 거쳐 출력하는 구조이다. 본 연구에서는 WLAN 규격에 적합한 DDC의 구조 및 설계방법 그리고 설계된 결과물의 시뮬레이션 결과에 대하여 분석하였다.