• Title/Summary/Keyword: Mobile Station

Search Result 1,003, Processing Time 0.029 seconds

Analysis of IT Technology through the Trends in Home Video Game Console (가정용 게임기 동향을 통해 본 IT 기술 분석)

  • Bae, Jung-Min;Bae, Yu-Mi;Jung, Sung-Jae;Jang, Rea-Young;Sung, Kyung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2014.05a
    • /
    • pp.675-678
    • /
    • 2014
  • One time, Home video game console's penetration was as comparable to the personal computer's penetration, growth has slowed since the advent of smartphones, tablets and moblie devices. But game console actively introducing new IT technologies not available in the pc games and mobile games, still keeping a firm position in the relevent market. In this paper Home video game console's history, contemporary trends, and learn about trends in the company, New IT technologies applied to gaming was analyzed. Home video console market become the arena of New IT technologies according to the introduction of New IT technologies such as gesture recognition technology, speech recognition technology, media facade technology, virtual reality technology.

  • PDF

Study on a Fully Electrified Car Ferry Design Powered by Removable Battery Systems Considering Domestic Coastal Environment

  • Hong, Jang Pyo;Kim, Young-Shik;Shim, Hyung-Won;Kang, Hee-Jin;Kim, YunHo;Kim, Gyu Bum;Cho, Seongpil
    • Journal of Ocean Engineering and Technology
    • /
    • v.35 no.1
    • /
    • pp.1-12
    • /
    • 2021
  • As increasing the international community's awareness of greenhouse gas reduction, the demand for eco-friendly ship fuel has accelerated recently. The fundamental aim of this study is to develop a new type of fully electrified ferry for passengers and cars considering Korean domestic coastal environmental conditions. Several technical difficulties are encountered in applying a fully electric propulsion system based on removable battery systems into a ship due to limitations imposed by the batteries' size and capacity. This paper reviews and analyzes marine environment regulations strengthened recently, technology trends related to fully electric propulsion vessels in each country, and Korean domestic coastal environments. We propose a new fully electrified car ferry design with a displacement of 400 t applied in Korea. It is powered by removable battery systems pre-charged in a safe inland charging station. The mobile battery system is developed to enable roll-on and roll-off using wheels. The characteristics of the ship motion are analyzed based on the weight and location of the battery systems. We expect our battery systems to be applicable to larger ships in the future.

A Secure and Efficient Roaming Mechanism for Centralized WLAN Environment (중앙집중식 WLAN 환경에서의 안전하고 효율적인 로밍 메커니즘)

  • Park, Chang-Seop;Woo, Byung-Duk;Lim, Jeong-Mi
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.19 no.1
    • /
    • pp.81-92
    • /
    • 2009
  • Recently, there is a drastic increase in users interested in real-time multimedia services in the WLAN environment, as the demand of IEEE 802.11 WLAN-based services increases. However, the handoff delay based on 802.11i security policy is not acceptable for the seamless real-time multimedia services provided to MS frequently moving in the WLAN environment, and there is a possibility of DoS attacks against session key derivation process and handoff mechanism. In this paper, a secure and efficient handoff mechanism in the centralized WLAN environment is introduced to solve the security problems. The 4-way Handshake for both mutual authentication and session key derivation is replaced by the 2-way Reassociation process.

Adaptive Detector Design for the Performance Improvement of Massive Antenna Systems (대용량 안테나 시스템의 성능 향상을 위한 적응형 검파기 설계)

  • Seo, Bangwon
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.21 no.1
    • /
    • pp.43-48
    • /
    • 2021
  • One of the effective ways to increase data transmission rate is to use massive antenna technique where tens or hundreds of antennas are deployed in base station and spatial diversity gain is improved by multiuser method. If multiuser method is applied, there will be inter-user interference and maximal ratio combiner (MRC) is conventionally used to reduce the complexity of the receiver and to eliminate interference. However, as the number of mobile devices increases, the performance of the conventional receiver becomes deteriorated. To solve this problem, we propose a new detector that completely eliminates the interference from the registered devices and reduces that from the unregistered devices. Then, to reduce the complexity of the proposed scheme, we propose adaptive algorithm of the proposed scheme. Through simulation, we show that the proposed scheme has better bit error rate performance than the conventional scheme.

Implementation of LTE Transport Channel on Multicore DSP Software Defined Radio Platform (멀티코어 DSP 기반 소프트웨어 정의 라디오 플랫폼을 활용한 LTE 전송 채널의 구현)

  • Lee, Jin
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.24 no.4
    • /
    • pp.508-514
    • /
    • 2020
  • To implement the continuously evolving mobile communication standards such as Long Term Evolution (LTE) and 5G, the Software Defined Radio (SDR) concept provides great flexibility and efficiency. For many years, a high-end Digital Signal Processor (DSP) System on Chip (SoC) has been developed to support multicore and various hardware coprocessors. This paper introduces the implementation of the SDR platform hardware using TI's TCI663x chip. Using the platform, LTE transport channel is implemented by interworking multicore DSP with Bit rate Coprocessor (BCP) and Turbo Decoder Coprocessor (TCP) and the performance is evaluated according to various implementation options. In order to evaluate the performance of the implemented LTE transport channel, LTE base station system was constructed by combining FPGA main board for physical channels, SDR platform board, and RF & Antenna board.

A Study on Improvement of 5G In-Building Quality using Antenna Orientation Principle (안테나 지향성 원리를 이용한 5G 건물 내 품질향상에 관한 연구)

  • Lee, Byung-Chan;Lee, Sung-Hwa;Kim, Jin-Tae
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.22 no.4
    • /
    • pp.41-48
    • /
    • 2022
  • This study is a study that designed in-building antennas with improved orientation to improve 5G quality in buildings as 5G is stabilized and more and more traffic is expected to occur in buildings. Instead of applying the forward arrangement of antenna elements, which is the Yagi antenna propagation orientation principle, the antenna design method of vertical arrangement applied to the base station antenna was proposed, and it was confirmed through experiments that antenna orientation increased. According to the experimental results, the directivity did not increase significantly within 10m of the separation distance from the antenna, but the directivity increased by about 3dB at the distance separated by more than 10m. Considering that the wireless environment in the building has various variables such as structure of internal structure, materials such as concrete and glass, closed space, and walls, it is expected that antenna with improved orientation can expand the scope of 5G quality improvement and maintain stable communication service in the building.

CNN-based Adaptive K for Improving Positioning Accuracy in W-kNN-based LTE Fingerprint Positioning

  • Kwon, Jae Uk;Chae, Myeong Seok;Cho, Seong Yun
    • Journal of Positioning, Navigation, and Timing
    • /
    • v.11 no.3
    • /
    • pp.217-227
    • /
    • 2022
  • In order to provide a location-based services regardless of indoor or outdoor space, it is important to provide position information of the terminal regardless of location. Among the wireless/mobile communication resources used for this purpose, Long Term Evolution (LTE) signal is a representative infrastructure that can overcome spatial limitations, but the positioning method based on the location of the base station has a disadvantage in that the accuracy is low. Therefore, a fingerprinting technique, which is a pattern recognition technology, has been widely used. The simplest yet widely applied algorithm among Fingerprint positioning technologies is k-Nearest Neighbors (kNN). However, in the kNN algorithm, it is difficult to find the optimal K value with the lowest positioning error for each location to be estimated, so it is generally fixed to an appropriate K value and used. Since the optimal K value cannot be applied to each estimated location, therefore, there is a problem in that the accuracy of the overall estimated location information is lowered. Considering this problem, this paper proposes a technique for adaptively varying the K value by using a Convolutional Neural Network (CNN) model among Artificial Neural Network (ANN) techniques. First, by using the signal information of the measured values obtained in the service area, an image is created according to the Physical Cell Identity (PCI) and Band combination, and an answer label for supervised learning is created. Then, the structure of the CNN is modeled to classify K values through the image information of the measurements. The performance of the proposed technique is verified based on actual data measured in the testbed. As a result, it can be seen that the proposed technique improves the positioning performance compared to using a fixed K value.

The Capacity Increase Scheme for Cellular based LPWA (Low Power Wade Area) IoT (이동통신 기반 LPWA (Low Power Wade Area) IoT를 위한 용량 증대 방안)

  • Park, Bok-Nyong;Jung, Il-Do
    • Journal of Internet of Things and Convergence
    • /
    • v.8 no.4
    • /
    • pp.17-23
    • /
    • 2022
  • NB-IoT and LTE Cat.M1 based on LPWA(Low Power Wide Area) are commercialized and serviced by mobile carriers. As the demand for IoT devices is increased, the number of subscribers to these services is also increasing. In the beginning of service, there was no issue that eNB capacity for NB-IoT and LTE Cat.M1. However, as the number of subscribers increases, there is an issue that the eNB capacity for these service is insufficient. Active UE capacity issue may cause overload by continuous increase and temporary increase. In this paper, we propose a solution to solve the problem of LTE RRC(Radio Resource Control) Active UE capacity shortage and base station overload caused by the increase of NB-IoT and LTE Cat.M1 UE in same eNB. The proposed solution can increase a cell capacity without cell division and additional eNB, and can also improve the service quality of these UEs.

A Mrthod on the Design of Sensor Network for the Surrounding Safety Using Drones (드론을 활용한 주변 안전을 위한 센서 네트워크 구성 방안)

  • Hong, Sung-Hwa
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2021.10a
    • /
    • pp.667-669
    • /
    • 2021
  • Recently, RFID/USN technology has been applied in various fields such as logistics, environment, education, home network, disaster prevention, military, and medical care, but despite the remarkable development of RFID/USN technology, it is difficult to apply it to marine industry due to the characteristics of poor marine environment. Therefore, satellites are mainly used in the marine sector, and existing communication networks are used in the coast, so measures for forming a shelf-only short-range network in the ocean are being considered. In this paper, we consider the use of drones as mobile base stations of USN as a base station role using USN in existing PS-LTE and LTE networks.Since autonomous navigation vessels are aiming for the intelligent system, the number of crew and labor force should be reduced and the function of autonomous network formation in the form of more stable and intelligent ICT convergence technology should be strengthened.

  • PDF

Demand Forecasting Model for Bike Relocation of Sharing Stations (공유자전거 따릉이 재배치를 위한 실시간 수요예측 모델 연구)

  • Yoosin Kim
    • Journal of Internet Computing and Services
    • /
    • v.24 no.5
    • /
    • pp.107-120
    • /
    • 2023
  • The public bicycle of Seoul, Ttareungyi, was launched at October 2015 to reduce traffic and carbon emissions in downtown Seoul and now, 2023 Oct, the cumulative number of user is upto 4 million and the number of bike is about 43,000 with about 2700 stations. However, super growth of Ttareungyi has caused the several problems, especially demand/supply mismatch, and thus the Seoul citizen has been complained about out of stock. In this point, this study conducted a real time demand forecasting model to prevent stock out bike at stations. To develop the model, the research team gathered the rental·return transaction data of 20,000 bikes in whole 1600 stations for 2019 year and then analyzed bike usage, user behavior, bike stations, and so on. The forecasting model using machine learning is developed to predict the amount of rental/return on each bike station every hour through daily learning with the recent 90 days data with the weather information. The model is validated with MAE and RMSE of bike stations, and tested as a prototype service on the Seoul Bike Management System(Mobile App) for the relocation team of Seoul City.