A5100698866- Advanced MIMO Systems Optimization
- Millimeter-Wave Propagation and Modeling
- Advanced Memory and Neural Computing
- Telecommunications and Broadcasting Technologies
- IoT Networks and Protocols
- CCD and CMOS Imaging Sensors
- Microwave Engineering and Waveguides
- Wireless Networks and Protocols
- Energy Harvesting in Wireless Networks
- Neural Networks and Reservoir Computing
- Robot Manipulation and Learning
- Cooperative Communication and Network Coding
- Robotic Path Planning Algorithms
- Robotics and Sensor-Based Localization
- Wireless Body Area Networks
- Semiconductor materials and devices
- Advanced Wireless Communication Technologies
- Neuroscience and Neural Engineering
- Satellite Communication Systems
- Hand Gesture Recognition Systems
- Underwater Vehicles and Communication Systems
- Microwave Dielectric Ceramics Synthesis
- Innovation in Digital Healthcare Systems
- Conducting polymers and applications
- Analytical Chemistry and Sensors
Seoul National University
2015-2024
Kyungpook National University
2024
Samsung (South Korea)
2013-2023
Kwangwoon University
2023
Electronics and Telecommunications Research Institute
2021-2022
Broadcom (Israel)
2013
Konkuk University Medical Center
2010
We report a VGA dynamic vision sensor (DVS) with 9µm pixel, developed through digital as well an analog implementation. DVS systems in the literature try to increase spatial resolution up QVGA [1–2] and data rates 50 million events per second (Meps) (self-acknowledged) [3], but they are still inadequate for high-performance applications such gesture recognition, drones, automotive, etc. Moreover, smallest reported pixel of 18.5µm is too large economical mass production [3]. This paper...
The on-going development of Fifth Generation (5G) mobile communication technology will be the cornerstone for applying Information and Communication Technology (ICT) to various fields, e.g., smart city, home, connected car, etc. 3rd Partnership Project (3GPP), which has developed most successful standard technologies in market such as Universal Mobile Telecommunication System (UMTS) Long Term Evolution (LTE), is currently carrying out standardization both 5G access network system core at...
This paper reports a 1280×960 DVS. A 4.95-μm pixel pitch is achieved with in-pixel Cu-Cu connection and the newly designed GIDL-suppression scheme. sequential column selection scheme global event-holding function are implemented to minimize motion artifacts. The power consumption per of 122 nW 1.25× smaller maximum readout speed 1.3 Geps 4.33× faster than previous state-of-the-art.
The 3rd Generation Partnership Project (3GPP) finalized Release 15 specifications for the 5th New Radio (5G NR) in June 2018. In 16, 3GPP worked on not only technical improvements over previous release but also introduction of new features. One features is use Two-step Random Access Channel (2-step RACH) that enhances 4-step random access with respect to radio resource control connection setup and resume procedures. this article, we first look into details 2-step defined briefly introduce...
Abstract A filamentary-based organic memristor is a promising synaptic component for the development of neuromorphic systems wearable electronics. In memristors, metallic conductive filaments (CF) are formed via electrochemical metallization under electric stimuli, and it results in resistive switching characteristics. To realize bio-inspired computing utilizing essential to effectively engineer CF growth emulating complete functions device. Here, fundamental principles underlying operation...
We introduce 5G K-SimNet, a network simulator for evaluating end-to-end performance of the fifth generation (5G) cellular system.5G K-SimNet provides features new radio (NR), core, multi-radio access technology (RAT) protocol, traffic management on multi-connectivity, and software-defined network/network function virtualization (SDN/NFV). In this paper, we present scenarios that can be simulated by using simulator, simulation results.
This paper studies the cross-layer challenges and performance of Hybrid Beamforming (HBF) Multi-User Multiple-Input Multiple-Output (MU-MIMO) in 5G millimeter wave (mmWave) cellular networks with full-stack TCP/IP traffic MAC scheduling. While previous research on HBF MU-MIMO has focused link-level analysis full-buffer transmissions, this work reveals interplay between techniques higher layers protocol stack. To aim, prior evaluation mmWave been extended by including modeling HBF. Our...
The IEEE 802.11WLAN adopts a random backoff algorithm for its collision avoidance mechanism, and it is well known that the contention-based may suffer from performance degradation especially in congested networks.In this paper, we design an efficient utilizes reinforcement learning method to determine optimal values of backoffs.The mobile nodes share common contention window (CW) our scheme, using Q-learning algorithm, they can avoid collisions by finding implicitly reserving their time...
We propose a novel method for identifying and classifying motions that offers significantly reduced computational cost as compared to deep convolutional neural network systems with comparable performance. Our new approach is inspired by the information processing architecture of biological visual systems, whereby spatial pyramid kernel features are efficiently extracted in real-time from temporally-differentiated image data. In this paper, we describe evaluate its performance hand motion...
We report on the neuromorphic sound localization circuit which can enhance perceptual sensation in a hearing aid system. All elements are simple leaky integrate-and-fire neuron circuits with different parameters optimized to suppress impacts of synaptic noises. The detection range and resolution proposed 500 us 5 us, respectively. Our results show that, technique localize pulse extremely narrow duration (∼ 1 ms) resulting real-time response.
In future cellular networks, performance target includes not only increasing data rate, but also reducing latency. The current LTE-Advanced systems require four message exchanges in the random access and uplink transmission procedure, thus inducing high this paper, we propose a 2-way scheme which effectively reduces proposed requires two messages to complete procedure at cost of increased number preambles. We study how generate such preambles utilize them. According extensive simulation...
Dynamic Vision Sensor (DVS) is an event sensor that asynchronously captures whenever there a brightness change in the scene. However, due to sensor's high temporal resolution property, it particularly vulnerable flicker. Numerous unwanted events caused by flickering can cause serious loads on computing power and prevent from extracting useful information, making difficult use for machine vision applications practice. In this demo, we propose PINK (PolarIty-based aNti-flicKer), which filters...
With the increasing number of Internet Things (IoT) devices, machine-type communication (MTC) has become an important use case fifth-generation systems. Since MTC devices are mostly disconnected from base station for power saving, random access procedure is required to transmit data. If many try simultaneously, preamble collision problem occurs, thus causing latency increase. In environment where delay-sensitive and delay-tolerant coexist, contention-based cannot satisfy requirements...
In the lateral access environment, robot be-havior should be planned considering surrounding objects and obstacles because object observation directions approach angles are limited. To safely retrieve a partially occluded target in these environments, we have to relocate using prehensile actions create collision-free path for target. We propose learning-based method rearrangement planning applicable of various types sizes environment. plan optimal sequence by both collisions at which can...
Fast and efficient motion estimation is essential for a number of applications including the gesture-based user interface (UI) portable devices like smart phones. In this paper, we propose highly method that can estimate four degree freedom (DOF) motional components moving object based on an event-based vision sensor, dynamic sensor (DVS). The proposed finds informative events occurred at edges estimates their velocities global analysis. We will also describe novel to correct aperture...
With the increasing number of Internet Things (IoT) devices, Machine Type Communication (MTC) has become an important use case Fifth Generation (5G) communication systems. Since MTC devices are mostly disconnected from Base Station (BS) for power saving, random access procedure is required to transmit data. If many try simultaneously, preamble collision problem occurs, thus causing latency increase. In environment where delay-sensitive and delay-tolerant coexist, contention-based cannot...
In Fifth-Generation (5G) New Radio (NR), satisfying a scenario called Ultra-Reliable and Low-Latency Communication (URLLC) is one of main goals. URLLC requires very high reliability with low latency, 1 ms user plane latency 99.999% reliability. Long Term Evolution-Advanced (LTE-A) system, however, requirement required by cannot be satisfied because resource allocation process increases latency. this paper, we propose DRaMA, grant-free uplink transmission scheme for in URLLC. With its own...
This paper investigates gate-induced drain leakage (GIDL) characteristics in a cell string consisting of gated-diode memory cells. Gated-diode cells have an oxide/ nitride/oxide gate dielectric stack to implement nonvolatile and are formed with select MOSFET located at one end. Gated diodes investigated regard performance. The current is the sum individual GIDL currents from It can be accurately controlled by programming or erasing Using 1×6 string, 6-b binary-weighted current-steering...
IEEE 802.15.4a standard enables location-aided routing or topology control in ZigBee networks, since it uses time-of-arrival (TOA)-based ranging technique. However, TOA based techniques may yield location error due to the non-line-of-sight (NLOS) effects, and hence degrade network performance. In this letter, we demonstrate impact of NLOS on localization performance propose a detection compensation algorithm for networks. The proposed detects by using min-max compensates Kalman filter....
DID(Decentralized IDentifiers)는 개인정보를 직접 관리할 수 있는 탈중앙화 신원 관리 체계이다. 블록체인 기반 DID 시스템에서의 전자서명은 VC(Verifiable Credential)를 서명하는데 사용된다. 그러나 현재 표준에서는 단일 서명 방식만을 지원하여 키 관리에 어려움이 있으며, 지점 장애가 발생할 있고 VC를 다자간 서명하는 것이 어렵다. 본 논문에서는 안전하게 서명이 가능한 시스템을 제안한다. W3C DID와 VC 표준에 따라 임계 기법을 사용 가능하고, 블록체인을 활용하여 문서를 관리하며, ECDSA 통해 가능하도록 설계하였다. Universal Resolver와 MPECDSA 라이브러리를 구현하였고, 주요 성능을 제시하였다. 결과 분석을 제안된 기법이 실현 가능함을 확인하였다. (Decentralized IDentifiers) is a decentralized identity management system that can...
As the wireless connections between every object have become important scenarios in future communications, industrial environments using massive type of machines also been emerging. To develop communication systems that can be used for environments, understanding and modeling propagation characteristics should preceded. Channel models describe various established system developments. In this paper, we present channel measurement campaign parameter extractions measured environment channels at...