• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.14 no.5
• /
• pp.209-214
• /
• 2014

IMS(IP Multi-Media Subsystem) is in the limelight as the Integrated wire and wireless Systems because of a sudden increase of smart mobile devices and growth of multimedia additional services such as IPTV. The structure of IMS is designed as a session control layer to provide various multimedia summative service using SIP based on IP communication network in order to carry out set-up, change and release by NGN of course, the existing voice services. But now It is broadly substituting in the IPTV, wire phone company and it is substituted in internet platform base on the soft-switch in currently. Especially, in currently, 4G LTE in a mobile communication company is rapidly growing in market. Therefore, in this study, we had designed and developed to the main prosser that can admit to 1000 user over and SIP gateway which can link the IMS Core that can link SIP Device which adopt the standard protocol on the SIP and to provide variable multimedia services.

• Journal of the Korean Society for Precision Engineering
• /
• v.19 no.5
• /
• pp.159-167
• /
• 2002

In this paper. we present a new method for monitoring of ECU's self diagnostic signals of vehicle without wire. In order to measure the ECU's self diagnostic signals, the interfaced circuit is designed to communicate ECU and designed terminal according to the IOS, SAE regulation of communication protocol standard. Micro-processor 80C196KC is used for communicating ECU's self diagnositc signals and the results are sent to the wireless terminal and PC monitoring system. Wireless terminal is also developed by 80C196KC, LCD, RF module, and keypad. The command from the keypad is sent to ECU through RF module and the result show on the Graphic LCD in real time. Software on PC is developed to monitor the ECU's self diagnostic signals using the Visual C++ complier in which RS232 port is programmed by half duplex method. The algorithms for measuring the ECU's self diagnostic signals are verified to monitor both ECU and portable terminal state. At the same time, the information to fix the vehicle's problem can be shown on the developed software. The possibility for remote measurement of ECU self diagnostic signal is verified through the developed systems and algorithms.

• Journal of the Korea Computer Industry Society
• /
• v.6 no.5
• /
• pp.821-828
• /
• 2005

This paper was proposed Intelligent and wireless USN/RFID module system that can overcome disadvantage of existing RFID system with no sensing module and wire communication. The proposed USN/RFID system was designed and fabricated. After fabricating new system, we analyzed the characteristics of USN/RFID module. After design VCO block that is point circuit to develop next generation system one chip of RFID system. we were carried out simulation and verified the validity, this paper was showed that VCO system was enough usable in wireless network module. USN/RFID Reader module shows superior result that validity awareness distance corresponds to 30M in the case of USN and to 5M in RFID Reader's case and 900MHz of commercial frequency does practical use enoughly in range of high frequency. The USN/RFID Reader module is considered to act big role to Ubiqitous industry offering computing surrounding of new concept that is intelligence type service and that was associated to real time location system(RTLS). environment improvement/supervision. national defense, traffic administration etc.

• Journal of Korea Multimedia Society
• /
• v.17 no.12
• /
• pp.1461-1472
• /
• 2014

Recently, smart devices has been spreaded and the definition of RFID/USN(Radio Frequency Identification/Ubiquitous Sensor Network) technology has also extended. So, originally, human is an agent of communications but now, 'the things' are also an agent of communication. That is, Internet of Things(IoT). IoT is very big IT infra technology that is based on wire-wireless network technologies such as Bluetooth and Wi-Fi. However, in reality, IoT service that can provide various meaning and integrate smoothly is not appear yet. To solve these problems of IoT, we implemented Publish/Subscribe system, which operate in Zigbee based wireless sensor network by using MQTT-SN protocol. Moreover, this system can operate with combining MQTT system that is already existed in external Internet network so, extensibility and flexibility aspect is excellent. We show that possibility of IoT services that is combined between different heterogeneous network through the MQTT-SN.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.9 no.5
• /
• pp.1642-1661
• /
• 2015

Wireless mesh networks are a special type of broadcast networks which cover the qualifications of both ad-hoc as well as infrastructure mode networks. These networks offer connectivity to the last mile through hop to hop communication and by comparatively reducing the cost of infrastructure in terms of wire and hardware. Channel assignment has always been the focused area for such networks specifically when using non-overlapping channels and sharing radio frequency spectrum while using multiple radios. It has always been a challenge for mesh network on impartial utilization of the resources (channels), with the increase in users. The rational utilization of multiple channels and multiple radios, not only increases the overall throughput, capacity and scalability, but also creates significant complexities for channel assignment methods. For a better understanding of research challenges, this paper discusses heuristic methods, measurements and channel utilization applications and also examines various researches that yield to overcome this problem. Finally, we highlight prospective directions of research.

• Journal of the Korea Society of Computer and Information
• /
• v.11 no.5 s.43
• /
• pp.259-265
• /
• 2006

As a core area of the new computing paradigm, the Ubiquitous Sensor Network Technology utilizes a wireless sensor networking which can be applied to the Context Information Monitoring System. When the technology is used in a poor user-environment for monitoring purposes, it can cost-effectively gather the context data on real-time basis, analyze the information gathered, effectively response to the user situation, and execute orders to create environmental factors desired by the user. This study structures a system able to monitor information in regards to a user-environment based on wireless-node sensor technology coupled with the Ubiquitous Sensor Network Technology. The proposed system requires a minimal collection of data without continuous monitoring. Monitoring periodically, it can sense the user-environment more efficiently than the existing monitoring technologies based on the wire-communication technology.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.4 no.3
• /
• pp.182-188
• /
• 2004

We demonstrate a $2.1\;{\times}\;1.0\;{\times}\;0.1cm^3$ sized compact transmitter using LTCC System-in-Package (SiP) technology for 60GHz-band wireless communication applications. For low-attenuation characteristics and resonance suppression of the SiP, we have proposed and demonstrated a coplanar double wire-bond transition and novel CPW-to-stripline transition integrating air-cavities as well as novel air-cavities embedded CPW line. The fabricated transmitter achieves an output of 13dBm at a RF frequency of 62GHz, an IF frequency of 2.4GHz, and a LO frequency of 59.6GHz. The up-conversion gain is 11dB, while the LO signal is suppressed with the image rejection mixer below -21.4dBc, and the image and spurious signals are also suppressed below -31dBc.

• Proceedings of the IEEK Conference
• /
• 2000.07a
• /
• pp.144-147
• /
• 2000

In this paper, we propose two receiver structures of the impulse radio (IR) system to improve its performance in multipath environments. Recently, the impulse radio system has drawn much attention for future high-speed wire-less communication services. The conventional IR receiver directly correlates received signals with the ideal reference waveform, which results in performance degradation in multipath environments. The Key idea of the proposed receiver structures is to reflect the multipath Characteristics into the IR receiver. One is to deconvolve the received waveform with estimates of the multipath gains to obtain the transmitted waveform while the other is to modify the reference waveform of the correlator according to the estimates of the multipath gains. We examine the performance of the proposed schemes for the statistical indoor wireless communication channel model using computer simulation.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.8 no.5
• /
• pp.1069-1075
• /
• 2007

New BESA cryptographic algorithm is suitable network environment and wire/wireless communication network, on implement easy, security rate preservation, scalable & reconfigurable. Though proposed algorithm strengthens security vulnerability of TCP/IP protocol and keep security about many user as that have authentication function in network environment, there is important purpose. So that new BESA cryptographic algorithm implemented by hardware base cryptosystem and en/decryption is achieved at the same time, composed architecture.

• Proceedings of the IEEK Conference
• /
• 1998.06a
• /
• pp.149-152
• /
• 1998

A synchronization is very important element not only wire communication but also wireless communication. A synchronous oscillator(SO) is a network which synchronizes, tracks, filter, amplifies and divides (if necessary) in a single process. The coherent phase synchronous oscillator(CPSO) is created by adding two external loops to the SO. The CPSO ratains all virtues of a SO while providing coherency throughout the tracking range. This paper has applied a clock recovery of GPS signal using CPSO.