적응계수 갱신율이 감소된 효율적인 적응채널등화기의 구조

양윤기 水原大學校 1997 論文集 Vol.15 No.-

In this paper, we introduce an efficient adaptation schemes for the conventional adaptive channel equalizer, which can reduce the hardware complexity. In the proposed adaptive channel equalizer, the computationally intensive adaptation logic is implemented with larger time span which can reduce the hardware speed for the adaptation logic as compared to conventional adaptive channel equalizer. The computer simulation results reveal that the performance of the proposed adaptive channel equalizer is comparable with that of conventional equalizer.

FPGA를 사용한 고해상도 PC 기반 DVR 보드 개발

양윤기 水原大學校 2013 論文集 Vol.27 No.-

In this paper, we develop PC based DVR system. The system is composed of FPGA and some analog components. The developed DVR system can handle 8 channel HD camera via SDI interface. The main functions are embedded in the devices. Also, PC windows drivers are developed to support user application program. The PC based DVR is much cheaper than any other stand-alone DVR system and the performance is comparable to the state of the art technologies of the DVR products.

고속 Graphic Processor를 사용한 대용량 데이터의 병렬연산 기법

양윤기 水原大學校 2020 論文集 Vol.34 No.-

Large scale data such as 3 dimensional data are difficult to be processed by normal PC environments. However, the GPUs (graphic processing unit) are widely employed to process the large scale data. Recently, the high performance GPUs are introduced with relatively low prices, which can be very useful to process multidimensional data. In this research, the industrial 3D data, typically 1000 x 1000 x 1000 volumetric data are computed with commercial low price GPU processors. Moreover, to enhance the computational performance, we use two independent GPUs. Recently, the MATLAB and some GPU makers made some excellent libraries that can be used by the normal users without sophisticated parallel computing theories. Computer simulations reveals that the dual GPU outperforms with respect to the conventional single GPU or without GPU processor.

고급 완구를 위한 고품질의 음성합성 모듈개발

양윤기,박창현 수원대학교 산업기술연구소 2002 산업기술연구소논문집 Vol.17 No.-

본 연구에서는 최근에 많이 쓰이고 있는 ARM사의 core를 사용한 chip를 사용하여 시간 영역에서 음성신호를 합성하는 방식인 PSOLA (pitch synchronous overlap and add) 방식을 사용한 음성합성 시스템을 개발하였다. 개발된 음성합성기는 flash memory를 사용하여 음절 데이터의 질을 한단계 더 향상시켰으며, 일반적으로 많이 사용되고 대용량 flash 메모리와의 인터페이스가 용이한 ARM 사의 core를 사용하여, 전체적인 시스템의 하드웨어를 설계 제작하였으며, PC 환경에서 알고리즘을 검증하고 이를 실제 제작한 하드웨어에서 실험하여 소정의 결과를 도출하였다.

실시간 문자-음성변환기의 하드웨어 구현

양윤기 水原大學校 1998 論文集 Vol.16 No.-

Recently, the data service in the wireless network is widely proposed. Especially, the text data is useful for the mobile station where the mobile station is connected in the vehicles. However, in that case, the text data should be converted into the speech data in order to guarantee navigation stability. Thus, in this paper, we develop a novel Korean text to speech(TTS) system which can be connected with conventional mobile terminals. The proposed TTS system is low-cost version as compared to the conventional Korean TTS system. We design the hardware system with ADSP-2185, 4 Mega bits ROM, Codecs. Also, the full software which can implement the realtime Korean TTS system is developed. The performance of the proposed TTS system is comparable that of the conventional system with much low cost, which can be employed in many mobile data service terminals.

DFT를 사용한 고속 constant modulus algorithm 의 성능분석

양윤기,이창수,양수미,Yang, Yoon-Gi,Lee, Chang-Su,Yang, Soo-Mi 한국전기전자학회 2009 전기전자학회논문지 Vol.13 No.1

Recently, some frequency domain CMA (Constant Modulus Algorithm) have been introduced in an effort to reduce computational complexities [1,2]. In [1], a fast algorithm that minimizing cost function designed for block input signal is employed, while in [2], a novel cost function that minimizing sample by sample input is used. Although, the two fast algorithm save computational complexities as compared to CMA, the convergence behaviors of the two fast algorithm show different results with repsect to CMA. Thus, in this paper, some analytical results on the error surface of the fast frequency domain CMA are introduced. From the analytical results, we show that the more recent algorithm [2] outperforms the previous algorithm [1]. Simulation results reveals that the recent algorithm [2] shows 50% enhanced convergence with respect to the old fast algorithm [1]. Also, we show that the recent fast algorithm [2] has comparable convergence performance with respect to conventional CMA algorithm.

계산량이 줄어든 새로운 적응블라인드 등화알고리듬

양윤기 水原大學校 2004 論文集 Vol.22 No.-

In this paper, a novel fast FBCMA(frequency domain block CMA) algorithm employing fast convolution in the DFT domain is proposed. In is similar to the FBLMS (frequency domain block LMS) which is used for linear adaptive filtering. But the main difference is the proposed algorithm need to minimize the nonlinear cost function in the frequency domain. In this paper, a new non-linear adaptation rules minimizing CMA cost function in DFT domain is proposed. The computer simulations result reveal that the proposed FBCMA shows the comparable performance to the conventional CMA, while requiring much less computations. The multiplications required for the conventional CMA and proposed FBCMA is in the order of O(N² and O(NlogN), respectively.

DC adapter 생산공정의 품질관리 시스템 개발

양윤기 水原大學校 2012 論文集 Vol.26 No.-

In this paper, we develop an automation system that can check the output voltage of the adapter. The developed systems are composed of DIO (digital input and output), DAQ (data acquisition) and some windows program. Also, an variable load resister board are designed and constructed with some relays which can check the proper voltage level for given current sink of the AC/DC adapter. The operating software are developed ensuring easy use of graphical menu for manufacturing systems.

다중레벨 Constant Modulus Algorithm을 사용한 블라인드 적응채널등화

양윤기 수원대학교 산업기술연구소 1998 산업기술연구소논문집 Vol.13 No.-

The CMA (constant modulus algorithm) is one of the widely used blind equalization algorithms. In an effort to derive a robust CMA algorithm for the high order QAM constellation, we introduce the MCMA (Multilevel-CMA) which adjusts the equalizer coefficients by employing adaptive modulus for each received symbols sets. In the proposed MCMA, the signal constellation is partitioned into several sets based on the signal magnitude. The constant modulus "Rp" used for the signal reference is derived for each constellation subsets. Also, the set partition threshold is employed for the received signal set partition. The computer simulation show that the proposed MCMA has much faster convergence with imporved BER (bit error rate) performance.

DSP를 사용한 computer telephony 시스템의 구현

양윤기 수원대학교 산업기술연구소 2000 산업기술연구소논문집 Vol.15 No.-

In this paper, the computer telephony integration (CTI) system is developed by using high speed digital signal processor (DSP). The developed system is intended to replace the imported CTI system with low cost design. The design and hardware development of the CTI system are presented in this paper. The developed system named MPPX-1 is composed of MCU (micro controller unit), several DSPs, and DAA(direct access arragement). The ARS (advanced record system), VMS (voice mailing system) and DTMF (dual tone multi frequency) as well as basic firmware are developed and tested in this work. The commercial product will be available sooner or later based on the designed prototypes.