• 한국위성정보통신학회논문지
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• 제8권2호
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• pp.88-93
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• 2013

지구 관측 영상을 획득하는 합성개구레이더의 해상도를 향상시키기 위해서는 광대역 첩신호 발생이 필수적으로 요구된다. 본 논문에서는 고해상도를 얻기 위한 저궤도 관측위성용 합성개구레이더의 광대역 신호 발생기를 설계하고 시험 모델 제작 및 기능 시험결과를 다루었다. 구현된 광대역 신호 발생기의 파형발생기는 위성에서 주로 적용되는 메모리맵 기반의 구조를 사용하였으며 내부는 파형 발생을 위한 디지털 모듈과 직교 변조를 위한 RF 모듈로 구성된다. 디지털 모듈의 메모리에 저장된 I/Q 신호는 D/A 변환기를 거쳐 RF 모듈로 전달되며 1275 MHz 기준 신호에 대해 직교 변조기를 거쳐 변조된다. 광대역 신호 발생기 검증을 위한 치구 및 GUI도 개발하였다. 시험 결과 대역폭 요구사항 144 MHz를 잘 만족하고 있음을 확인하였다. 또한 사전 왜곡 보상 기능을 구현하여 발생된 왜곡이 보상됨을 확인하였다.

• 한국항공운항학회지
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• 제18권1호
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• pp.11-18
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• 2010

GNSS(Global Navigation Satellite System) Ground Station performs GNSS signal acquisition and processing. This system generates error correction information and distributes them to GNSS users. GNSS Ground Station consists of sensor station which contains receiver and meteorological sensor, monitoring and control subsystem which monitors and controls sensor station, control center which generates error correction information, and uplink station which transmits correction information to navigation satellites. Monitoring and control subsystem acquires and processes navigation data from sensor station. The processed data is transmitted to GNSS control center. Monitoring and control subsystem consists of data acquisition module, data formatting and archiving module, data error correction module, navigation determination module, independent quality monitoring module, and system maintenance and management module. The independent quality monitoring module inspects navigation signal, data, and measurement. This paper introduces independent quality monitoring and performs the analysis using measurement data.

• 센서학회지
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• 제26권6호
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• pp.432-437
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• 2017

As 4.0 industry has been developed, research on a self-driving car technology and related parts of an automobile has been highly investigated recently. Particularly, a TAS(Torque Angle Sensor) module on steering wheel system has been considered as a key technology because of its precise angle, torque detection and high speed signal processing. The environmental assessment is generally required on the TAS module to examine high resolution of angle/torque detection. In the case of existing TAS module, angle detection errors has been occurred by back-lash on main and sub gear in addition to complicated structure caused by gears. In this paper, a structure of the TAS module, which minimizes the numbers of components and angle detection errors on the module compared with the existing TAS module, for vehicle steering system based on a Multi-track Encoder has been proposed. Also, angle detection signal processing board, and key technology of the TAS module were fabricated and evaluated. As a result of the experiments, we confirmed an excellent performance of the fabricated signal processing board for angle detection and an applicability of the fabricated angle detection board on the TAS module of vehicles by the environmental assessment an automobile standard.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.2055-2056
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• 2011

As rapid aging and high economic level, people are interested in their wellness. And it needs to examine the condition of their health constantly. Proposed device can measure bio-signal by connecting several measurement modules such as spirometric module, blood glucose measurement module, uro-flow measurement module and temperature measurement module. These modules can be chosen as occasion demands. In addition, developed user program enables patients to monitor bio-signal at their own place via the personal computer.

• 한국정밀공학회지
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• 제19권12호
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• pp.179-184
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• 2002

In this study, we developed a portable device which can monitor and analyze vibration signals from machines. This system consists a PDA loading the program for vibration analysis and A/D board for vibration acquisition. A PDA is smaller than the palm of the hand, but it has a powerful computing ability as much as an IBM compatible PC with a Pentium 100MHz CPU. The A/D board developed in this study supports LAN interface using TCP/IP communication protocol. The application program for vibration analysis includes signal processing module, fault diagnosis module, data store module, and plot display module. MS visual embedded C＋＋ 3.0 was used to developed the program.

• 한국멀티미디어학회논문지
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• 제20권11호
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• pp.1803-1810
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• 2017

A large amount of processing time is required if the process of detecting the touch position on the touch screen and displaying it on the display panel is performed only by software. In this paper, we propose a method to output information touched on the screen using H/W method in order to improve the response speed delay. In the FPGA module designed for the HDMI signal output to the display module, the touch information is input to the serial data signal including touch coordinate information, point size, and color information. Then the module render the image using HDMI signal input to the module and the touch information. This method has a pipeline structure so it has effect of reducing the delay time that occurs in outputting the touch information compared with the conventional software processing method.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.318-321
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• 2000

This paper propose the method of constructing the highly efficiency adder and multiplier systems over finite fie2, degree of uk terms, therefore we decrease k into m-1 degree using irreducible primitive polynomial. We propose two method of control signal generation for perform above decrease process. One method is the combinational logic expression and the other method is universal signal generation. The proposed method of constructing the highly adder/multiplier systems is as following. First of all, we obtain algorithms for addition and multiplication arithmetic operation based on the mathematical properties over finite fields, next we construct basic cell of A-cell and M-cell using T-gate and modP cyclic gate. Finally we construct adder module and multiplier module over finite fields after synthesize ${\alpha}$$\^$k/ generation module and control signal CSt generation module with A-cell and M-cell. Then, we propose the future research and prospects.

• 한국전자통신학회논문지
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• 제10권10호
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• pp.1079-1086
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• 2015

본 논문은 안전 무결성 레벨이 4(: Safety Integrity Level 4)인 안전 관련 시스템에 적합한 출력 모듈의 구조를 설계하였고, 설계된 출력 모듈에 요구되는 정량적 목표치의 수준을 제시하였다. 특히 다양한 출력 방식 중에서 릴레이 출력 신호와 아날로그 신호로 구성된 출력 모듈이 안전 기능을 수행하는 시스템의 구성 요소인 경우를 적용하였다. 분석 방법은 FMEA(: Failure Modes and Effect Analysis), FTA(: Fault Tree Analysis) 방식을 이용하였다. 그 결과로 철도 응용 규격인 IEC 62425의 요구사항을 준수하는 SIL4 안전 관련 시스템의 출력 모듈의 구조와 고장빈도인 정량적 목표치를 제시하였다.

• IEIE Transactions on Smart Processing and Computing
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• 제4권4호
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• pp.258-264
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• 2015

The first 77 GHz transceiver that applies a heterodyne structure-based linear frequency modulation-frequency shift keying (LFM-FSK) front-end module (FEM) is presented. An LFM-FSK waveform generator is proposed for the transceiver design to avoid ghost target detection in a multi-target environment. This FEM consists of three parts: a frequency synthesizer, a 77 GHz up/down converter, and a baseband block. The purpose of the FEM is to make an appropriate beat frequency, which will be the key to solving problems in the digital signal processor (DSP). This paper mainly focuses on the most challenging tasks, including generating and conveying the correct transmission waveform in the 77 GHz frequency band to the DSP. A synthesizer test confirmed that the developed module for the signal generator of the LFM-FSK can produce an adequate transmission signal. Additionally, a loop back test confirmed that the output frequency of this module works well. This development will contribute to future progress in integrating a radar module for multi-target detection. By using the LFM-FSK waveform method, this radar transceiver is expected to provide multi-target detection, in contrast to the existing method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권9호
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• pp.2846-2866
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• 2022

Caenorhabditis elegans exhibits sophisticated chemotaxis behavior through two parallel strategies, klinokinesis and klinotaxis, executed entirely by a small nervous circuit. It is therefore suitable for inspiring fast and energy-efficient solutions for autonomous navigation. As a random search strategy, the Lévy walk is optimal for diverse animals when foraging without external chemical cues. In this study, by combining these biological strategies for the first time, we propose a spiking neural network model for search and contour tracking of specific concentrations of environmental variables. Specifically, we first design a klinotaxis module using spiking neurons. This module works in conjunction with a klinokinesis module, allowing rapid searches for the concentration setpoint and subsequent contour tracking with small deviations. Second, we build a random exploration module. It generates a Lévy walk in the absence of concentration gradients, increasing the chance of encountering gradients. Third, considering local extrema traps, we develop a termination module combined with an escape module to initiate or terminate the escape in a timely manner. Experimental results demonstrate that the proposed model integrating these modules can switch strategies autonomously according to the information from a single sensor and control steering through output spikes, enabling the model worm to efficiently navigate across various scenarios.