• Journal of information and communication convergence engineering
• /
• v.6 no.1
• /
• pp.91-93
• /
• 2008

To realize high-speed over GHz bps, it is needed to reduce and suppress the pulse width because of dispersion effect in fiber. We analyzed the performance and waveform due to chirping effect in fiber.

• Journal of Digital Convergence
• /
• v.17 no.10
• /
• pp.223-232
• /
• 2019

With the development of the information communication industry, the size of the communication device has been reduced to a system that generates a large amount of heat. Therefore, since the amount of heat generated by the wireless equipment is large in the wireless base station, the energy consumption is continuously consumed and the failure of the wireless base station may occur. Therefore, in this study, The study was analyzed. As a research method, we performed base station with a lot of calorific value and electric charge. We selected 25 base stations and obtained data for two weeks. To ensure reliability, the room temperature was kept constant at $27^{\circ}C$, and the control system was installed and equiped for two weeks to obtain the date analysis. In order to calculate the test results in the study method, the instrument was used with a computer, a digital thermometer, and dust measurement. For the date analysis, we conducted a research study on 25 wireless basestations before and after the installation of Control Sysetm.

• Electronics and Telecommunications Trends
• /
• v.33 no.5
• /
• pp.24-32
• /
• 2018

With the advent of new convergence services, the requirements of 5G mobile communication systems are being newly derived. The 5G mobile communication system has been evolving to solve requirements that cannot be satisfied with existing 4G mobile communication systems, such as a high user experience transmission rate, short transmission delay, and high connection density. The evolution of a 5G mobile communication system to meet the new requirements is expected to be dominated by the UDN environment in which a number of small cells are concentrated. The 5G wireless backhaul system, which has advantages in terms of initial installation and operation cost, is expected to be an indispensable choice for connecting many small cells and core networks. This paper therefore looks at the frequency band characteristics and requirements applicable to 5G wireless backhaul systems that can accommodate new situations, and introduces key related technologies that can satisfy the 5G wireless backhaul requirements.. In addition, we describe the research and development trends of a 5G wireless backhaul system that is currently under development.

• Smart Structures and Systems
• /
• v.30 no.5
• /
• pp.433-446
• /
• 2022

Despite efforts to reduce unexpected accidents at confined construction sites, choking accidents continue to occur. Because of the poorly ventilated atmosphere, particularly in long, confined underground spaces, workers are subject to dangerous working conditions despite the use of artificial ventilation. Moreover, the traditional monitoring methods of using portable gas detectors place safety inspectors in direct contact with hazardous conditions. In this study, a long-range (LoRa)-based wireless safety monitoring system that features the network organization, fault-tolerant, power management, and a graphical user interface (GUI) was developed for underground construction sites. The LoRa wireless data communication system was adopted to detect hazardous gases and oxygen deficiency within a confined underground space with adjustable communication range and low power consumption. Fault tolerance based on the mapping information of the entire wireless sensor network was particularly implemented to ensure the reliable operation of the monitoring system. Moreover, a sleep mode was implemented for the efficient power management. The GUI was also developed to control the entire safety-monitoring system and to manage the measured data. The developed safety-monitoring system was validated in an indoor testing and at two full-scale water pipeline construction sites.

• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 2006.07a
• /
• pp.425-425
• /
• 2006

• Journal of information and communication convergence engineering
• /
• v.7 no.3
• /
• pp.258-262
• /
• 2009

A Practical application of environmental monitoring system based on wireless sensor node network with the core of embedded system STR711FR2 microprocessor is presented in the paper. The adaptable and classifiable wireless sensor node network is used to achieve the data acquisition and multi-hop wireless communication of parameters of the monitoring base station environment including repeaters. The structure of the system is proposed and the hardware architecture of the system is designed, and the system operating procedures is proposed. As a result of field test, designed hardware platform operated with 50kbps bit rate and 5MHz channel spacing at 2040Hz. The wireless monitoring system can be managed and swiftly retreated without support of base station environmental monitoring.

• Convergence Security Journal
• /
• v.17 no.4
• /
• pp.3-9
• /
• 2017

Recently, Wireless communication has been widely used as a short distance communication medium in various industrial fields as well as communication connection between home appliances due to the appearance of the Internet of Things. And Most commonly used wireless communication media include WiFi, Bluetooth, and NFC. Among them, Bluetooth is widely used for communication between smart devices as well as computer peripheral devices. And Bluetooth in the home network fields is being used to control electronic products. However, since Bluetooth security vulnerabilities are known, more and more attacks are being exploited. As the application range of Bluetooth is expanding, it is necessary to prepare countermeasures accordingly. Therefore, this study investigates the security threat factors of through Bluetooth'attack case and attack technology. And By proposing countermeasures against this problem, we intend to utilize it as data for improving the security of wireless network service in the future.

• Convergence Security Journal
• /
• v.4 no.3
• /
• pp.27-35
• /
• 2004

A current trend in telecommunication is the convergence of wireless communication and computer network technologies, and the emergence of wireless application protocol(WAP) devices is an example. Computer system managers are often requested to solve urgent system problems. Many times, they cannot access a computer to perform remote system management tasks. Aiming at solving this problem, this paper presents a novel tool for system management that uses a WAP interface, and focuses on the description of the architecture and the associated application modules.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.11 no.4
• /
• pp.203-207
• /
• 2011

LED is in the spotlight as next generation's lighting due to the fact that it has good efficiency on converting electricity to light and has long life time. Recently it expands the scope up to taillight of car, signal lamp and indoor light. Additionally it can send data information simultaneously with lighting, which is called lighting-communication convergence. In this paper, the channel characteristics of LED wireless communication is studied in the condition that indoor is latticed with 1mm span and photons started from LED are firstly arrived at each lattice after that these move as straight line before meeting photodiode(PD).

• International Journal of Internet, Broadcasting and Communication
• /
• v.13 no.4
• /
• pp.121-128
• /
• 2021

In order to design a real time big data collection and analysis system of manufacturing data in a smart factory, it is important to establish an appropriate wired/wireless communication system and protocol. This paper introduces the latest communication protocol, OPC-UA (Open Platform Communication Unified Architecture) based client/server function, applied user interface technology to configure a network for real-time data collection through IoT Integration. Then, Database is designed in MES (Manufacturing Execution System) based on the analysis table that reflects the user's requirements among the data extracted from the new cutting process automation process, bush inner diameter indentation measurement system and tool monitoring/inspection system. In summary, big data analysis system introduced in this paper performs SPC (statistical Process Control) analysis and visualization analysis with interface of OPC-UA-based wired/wireless communication. Through AI learning modeling with XGBoost (eXtream Gradient Boosting) and LR (Linear Regression) algorithm, quality and visualization analysis is carried out the storage and connection to the cloud.