• IEIE Transactions on Smart Processing and Computing
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• v.4 no.1
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• pp.44-50
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• 2015

This paper presents a high speed synchronous single inductor dual output boost converter using Type-III compensation for power management in smart devices. Maintaining multiple outputs from a single inductor is becoming very important because of inductor the sizes. The uses of high switching frequency, inductor and capacitor sizes are reduced. Owing to synchronous rectification this kind of converter is suitable for SoC. The phase is controlled in time sharing manner for each output. The controller used here is Type-III, which ensures quick settling time and high stability. The outputs are stable within $58{\mu}s$. The simulation results show that the proposed scheme achieves a better overall performance. The input voltage is 1.8V, switching frequency is 5MHz, and the inductor used is 600nH. The output voltages and powers are 2.6V& 3.3V and 147mW &, 230mW respectively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.10A
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• pp.816-822
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• 2011

This paper provides the performance measurement and analysis of Wireless LAN IEEE 802.11 in a mobile environment. The performance of IEEE802.11b/g and IEEE802.11p that is designed for Vehicle-to-Vehicle(V2V) communication is measured and analyzed. Diameter of communication, link access time and delay are measured as vehicle's speed varies. Also, the performance is checked in a situation that the load to network varies. In conclusion, the futher research topics are discussed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.9 no.1
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• pp.1-10
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• 1984

The time division multiplexing PCM encoder which is constructed for an airborne telemetering system is investigated. Selected by program switch, the PCM encoder has 0~64 words/framd($\pm$5V full scale) of allowable analog input channels, 0~30bits(5V$\pm$1V or 0V$\pm$1V dc) of discrete channels, 70 and 140K bits/sec of bit rate and 8~12bits/word of resolution. And filtered output PCM code is NRZ-L and Bi-S through the 5 pole Bessel LPF(f=100kHz), and the maximum accuracy of PCM encoder is $\pm$0.2% of its full scale.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.1
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• pp.96-107
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• 2015

VANET technologies provide real-time traffic information for mitigating traffic jam and preventing traffic accidents, as well as in-vehicle infotainment service through Telematics/Intelligent Transportation System (ITS). Due to the rapid increasement of various requirements, the vehicle communication with a limited resource and the fixed frame architecture of the conventional techniques is limited to provide an efficient communication service. Therefore, a new flexible operation depending on the surrounding situation information is required that needs an adaptive design of the network architecture and protocol for efficiently predicting, distributing and sharing the context-aware information. In this paper, Vehicle-to-Infrastructure (V2I) based on communication between vehicle and a Road Side Units (RSU) and Vehicle-to-Vehicle (V2V) based on communication between vehicles are effectively combined in a new MAC architecture and V2I and V2V vehicles collaborate in management. As a result, many vehicles and RSU can use more efficiently the resource and send data rapidly. The simulation results show that the proposed method can achieve high resource utilization in accordance. Also we can find out the optimal transmission relay time and 2nd relay vehicle selection probability value to spread out V2V/V2I collaborative schedule message rapidly.

• Information and Communications Magazine
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• v.34 no.6
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• pp.11-19
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• 2017

V2X(Vehicle to Everything)는 차량 간 통신(Vehicle-to-Vehicle), 차량과 인프라 간 통신(Vehicle-to-Infrastructure), 차량과 보행자 간의 통신(Vehicle-to-Pedestrians) 등 운전 중 도로 인프라 및 다른 차량과 통신하면서 교통상황 등의 정보를 교환하거나 공유하는 기술을 말한다. V2X는 IT 기술의 발달과 여러 연구기관들의 연구개발 강화로 인해 'Connected/Smart car' 나아가 완전한 자율주행차를 구현하기 위해 빠르게 진화하고 있다. 이러한 V2X 시장이 향후 10년 간 급속한 확대가 전망되면서, 국내외 통신업체와 제조업 및 산학연은 자동차와 정보통신, 에너지, 서비스 산업을 융합한 스마트자동차 산업을 신성장 동력으로 하여 기술개발에 노력을 가속화하고 있다. 이에 본고에서는 V2X 차량 통신 기술의 주요선진국 기술개발 동향과 현 수준을 알아본다.

• Communications of the Korean Mathematical Society
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• v.12 no.1
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• pp.127-133
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• 1997

In order to study the limits of sequences appearing in, for example, stochastic process, A. V. Skorokhod has defined new function space topologies. We compare these topologies with the topology of compact convergence, the topology of pointwise convergence and others.

• Proceedings of the Korea Information Processing Society Conference
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• 2023.05a
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• pp.79-80
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• 2023

CPU 와 GPU 의 성능이 지속적으로 발전함에 따라 객체 인식 인공지능의 정확도와 추론 속도는 점차 향상되고 있으나 이러한 성능을 Edge Device 와 같은 제한된 환경에서 구현하기에 아직 여러 한계점이 존재한다. 본 논문에서는 여러가지 Edge Device 에서 객체 인식을 위한 경량화 된 모델 중 하나인 SSD-Mobilenet-V2 를 활용하여 결과값을 통해 각 Device 간 경향성을 분석하였다. 본 결과를 바탕으로 다양한 환경에서의 객체인식 인공지능 모델의 성능 개선을 위한 연구에 활용할 수 있다.

• Information and Communications Magazine
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• v.34 no.6
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• pp.20-26
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• 2017

본고에서는 차량 안전과 자율주행 서비스 개념을 설명하고 이러한 서비스를 제공하기 위한 5.9GHz WAVE 통신 기술 개발과 3GPP V2X 통신 기술 표준화 현황을 설명한다. 그리고 ETRI 에서 연구하고 있는 V-Link 통신 기술의 개발과 향후 전망을 소개하고자 한다.

• Communications of the Korean Institute of Information Scientists and Engineers
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• v.29 no.9
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• pp.13-18
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• 2011

바야흐로 21 세기를 열었던 유비쿼터스 기술은 그 결과물로써 스마트 기기를 낳았다. 그리고 본격적으로 스마트 시대를 열었다. 이에 단순히 탈것에서 진화하기 시작한 자동차는 IT기술과의 접목을 자연스레 하게 되었으며 이어서 스마트 자동차로의 진화적 완성을 시도하고 있다. 이러한 스마트 자동차는 기본적으로 차량 통신 네트워크 기술은 차량내 네트워크(IVN), 차량간 통신 네트워크(V2V communication network), 그리고 차량과 인프라간 통신 네트워크(V2I communication network)로 구성이 된다. 본 고에서는 차량 통신 네트워크 기술의 개념과 서비스, 시장 전망, 그리고 최근 기술개발과 표준화 동향을 알아본다.

• ETRI Journal
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• v.30 no.2
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• pp.268-274
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• 2008

This paper proposes an open-loop clock recovery circuit (CRC) using two high-Q dielectric resonator (DR) filters for 39.8 Gb/s and 42.8 Gb/s dual-mode operation. The DR filters are fabricated to obtain high Q-values of approximately 950 at the 40 GHz band and to suppress spurious resonant modes up to 45 GHz. The CRC is implemented in a compact module by integrating the DR filters with other circuits in the CRC. The peak-to-peak and RMS jitter values of the clock signals recovered from 39.8 Gb/s and 42.8 Gb/s pseudo-random binary sequence (PRBS) data with a word length of $2^{31}-1$ are less than 2.0 ps and 0.3 ps, respectively. The peak-to-peak amplitudes of the recovered clocks are quite stable and within the range of 2.5 V to 2.7 V, even when the input data signals vary from 150 mV to 500 mV. Error-free operation of the 40 Gb/s-class optical receiver with the dual-mode CRC is confirmed at both 39.8 Gb/s and 42.8 Gb/s data rates.