• Journal of Broadcast Engineering
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• v.15 no.2
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• pp.157-162
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• 2010

In this paper, We propose that the adaptive cooperative relay transmission technique using closed-loop MIMO scheme for duplex communication system. As the mobility between relay and base station is little, closed-loop MIMO is better diversity gain than open-loop MIMO. At this time, more than one relaying terminals are included in one cooperative group to share their transmission and take precoding weight feedback. For minimization of throughput reduction caused by increasing feedback bits, we use codebook-based MRT that limit the number of feedback bits. Among the cooperative relay group, the best relays are selected from the base stataion and get the feedback. A protocol senarios are also proposed for this relay system.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.6
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• pp.552-557
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• 2017

Wire, wireless digital broadcasting has sharply expanded with the birth of high definition TV since 2010, the use of duplex contents as well as simplex contents has rapidly increased. Currently, our satellite communications system adopted DVB by European digital broadcasting standardization organization as a standard of domestic data broadcasting, the method how to use selective contents has been studied variously according to the development of IPTV. Digital broadcasting utilizes the method using Transport Stream Packet(TSP) by the way of multiplexing of information in order to send multimedia information such as video, audio and data of MPEG-2, this streams include detail information on TV guide and program as well as video and audio information. In order to understand these data broadcasting system, this study realized TS analyzer that divides transport stream (TS) by packet in Linux environment, analyzes and prints by function, it can help the understanding of TS, the enhancement of stream parsing ability.

• Journal of Advanced Navigation Technology
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• v.27 no.4
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• pp.453-456
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• 2023

Fighter jets employ guided missiles equipped with seekers to counter enemy air threats. Short range guided missiles(SRM) usually carry infrared(IR) seekers and are used to engage targets within visual range. On the other hand, medium range guided missiles(MRM) often utilize radio frequency(RF) seekers to engage targets beyond visual range. Medium range guided missiles do not activate their seekers until they reach the detection range of the seeker, and the aircraft's radar guides them for a certain distance. This guidance method is called Missile Data Link(MDL), and it can be implemented in either one-way or two-way communication modes, depending on the missile's communication system. In this paper, we discuss MDL based on these two communication modes, along with the integration of RADAR, mission computers, and guided missiles.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.3
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• pp.587-594
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• 2010

In this paper, we propose an asynchronous IR-UWB ranging system based on the two-way ranging protocol. The periodic pulse sequence is used to measure a distance between two devices. At the receiver, a received signal is first transformed into a frequency-domain signal using an analog correlator bank and digital signal processing is followed in the frequency-domain. This make it possible for the system to use an ADC with a conversion speed of pulse rate. The proposed algorithm at the receiver side includes a peak detection procedure using mutipath channel compensation and matched filtering, and retransmits a pulse sequence synchronized with the detected peak. The validity of the proposed algorithm is verified from simulation results where the CM1 channel is assumed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.6
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• pp.225-233
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• 2010

Recently, in the field of Smart Grid, Smart Home Network, Ubiquitous Computing, etc. we have continued to study Smart Information Monitoring Technology(SIMT) which exchange, control and monitor information collected and processed by need in real-time and two-way. In this paper, we understand application products or recent trends of SIMT for Energy, U-Farm, Vehicle Information and Home Network. Specially, we explain Google PowerMeter which exchange information with Smart Meter of core part of the smart grid at real-time, Real-time Monitoring System(RMS) for U-Farm, RMS for vehicle status Information. we subscribe Smart Information Monitoring Technology application based on ZigBee of low price, low power or related work. Finally we subscribe actual proof construction situation of Jesu for smart grid.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.2 no.1
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• pp.37-42
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• 2009

The digital filter is essential element in digital signal processing area. It needs a high computational burden caused by multiplying and adding. The multiplier in digital filter is a dominant element, which occupies an wide area at the field of VLSI design, needs high power-consuming and also decides critical path that affects to filter performance. In this paper we proposed the simultaneous transform method which is represented 2's complementary representation to CSD and MSD representation to solve a complexity problem and to improve a computational speed. The performance of proposed method was implemented in VHDL and applied to an digital filters, was evaluated the decreasing of critical path delay.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.3A
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• pp.160-167
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• 2005

The gain-clamped EDFA has been developed to eliminate the output power change of WDM surviving channels to occur with added or dropped channels, which degrades the performance of WDM optical network. It maintains the constant gain of surviving channels when WDM channels are added or dropped in a network amplifying node. In this paper, the hi-directionally pumped gain-clamped EDFA is implemented to compensate the change of the input power by a lasing. The results show that the lasing of a short wavelength and backward propagation is the optimal condition to minimize the transient response of surviving channels in terms of the overshoot and gain saturation due to the inhomogeneous broadening effect.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.5 no.2
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• pp.68-73
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• 2012

This paper is an analysis the performance of CDMA system using array antenna beamforming technique in wireless channels. Adaptive array beamforming antenna technique combine receive signal amplitude with phase in array antenna element, and can be incremental spatial filter function a direction of arrival signal using weight value. Through simulation, in this paper, we were an analysis to compare bit error rate of forward and backward channels using array antenna beamforming technique in order to interference signal decrease of CDMA fading enviroment. The result simulation, we get spatial diversity effect by using array antenna system, and improved the performance to MAI interference decrease.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.06a
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• pp.657-660
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• 2007

With progress of informationalization, education has been transformed from traditional uni-direction education to bi-directional and consumer-oriented education, which is performed by learner's self study and interactive education of multiple dimension between a learner and contents, between a learner and a teacher, and between a learner and a learner irrespective of space-time. According to this trend, a new education method has been required. Therefore, in this paper, we will propose real-time consumer-oriented distance education system of making interaction maximum using WBI. In this system, a learner can participate in an individual study case by multiple interaction with a learner's designing and plaining study, and also participate in group study case by way of discussion and conversation among participants.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2B
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• pp.361-371
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• 2010

To vitalize the terrestrial DMB market, we introduce a personalized DMB(PDMB) service model based on metadata, especially DMB ECG XML standardized by TTA, under the convergence of broadcasting and telecommunications. Also we introduce the personalized DMB service system developed to validate the conformance of DMB ECG XML standard and the usefulness of DMB ECG service. The personalized DMB service system is described in details from the authoring stage to the consumption stage of the contents. The results of experimental tests for the personalized DMB service system are also introduced in this paper. We finally address the possibility of making successful personalized DMB services in mobile multimedia broadcasting market.