• The Journal of Korean Institute of Communications and Information Sciences
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• v.37C no.12
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• pp.1185-1194
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• 2012

This paper proposes a new terrestrial 3DTV broadcasting standard specification based on synchronization with non-real-time contents in order to overcome quality limitations of the current 3DTV services that are arisen from the limited bandwidth of the legacy broadcasting channel. In the services using the proposed specification, one view sequence of a stereoscopic video content is delivered as a non-real-time content in idle time, and the other view sequence is transmitted in real time broadcasting signal, thereafter two sequences are synchronized in a receiver for display. Thus, it is possible to provide higher-quality stereoscopic video content services than the current 3DTV services. In order to realize these services, a new mechanism is required which enables synchronization between the data that are from different transmission media and time. Therefore, this paper suggests a solution by multiplexing the synchronization signals of non-real-time contents into broadcasting signals with real-time streams together. This solution can provide a accurate synchronization mechanism by minimum updates of legacy broadcasting systems while maintaining compatibility with legacy services.

• Journal of Sensor Science and Technology
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• v.10 no.1
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• pp.1-8
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• 2001

Conventional microgyroscopes of vibrating type require resonant frequency tuning of the driving and sensing modes to achieve high sensitivity. These tuning conditions depend on each fabricated microgyroscopes, even though the microgyroscopes are identically designed. A new micromachined resonator, which is applicable to microgyroscopes with self-toning characteristics, is presented. Since the laterally driven two degrees of freedom (2DOF) resonator was designed as a symmetric structure with identical stiffness in two orthogonal axes, the resonator is applicable to vibrating microgyroscopes, which do not need mode tuning. A dynamic model of the resonator was derived considering gyroscopic application. The dynamic model was evaluated by experimental comparison with fabricated resonators. The microgyroscopes were fabricated using a simple 2-mask-process of a single polysilicon layer deposited on an insulator layer. The feasibility of the resonator as a vibrating microgyroscopes with self-tuning capability is discussed. The fabricated resonators of a particular design have process-induced non-uniformities that cause different resonant frequencies. For several resonators, the standard deviations of the driving and sensing frequencies were as high as 1232Hz and 1214Hz, whereas the experimental average detuning frequency was 91.75Hz. The minimum detuned frequency was 68Hz with $0.034mVsec/^{\circ}$ sensitivity. The sensitivity of the microgyroscopes was low due to process-induced non-uniformity; the angular rate bandwidth, however, was wide. This resonator could be successfully applicable to a vibrating microgyroscopes with high sensitivity, if improvements in uniformity of the fabrication process are achieved. Further developments in improved integrated circuits are expected to lower the noise level even more.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.4
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• pp.61-70
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• 2008

This paper designed the antenna for collecting and servicing the traffic information that apply to freeway Traffic Management System, as using DSRC (Dedicated Short Range Communication). Active DSRC is the technology that is using 5.8GHz Radio Frequency to a mean Sequency and there are a lot of the case occurring a physical electric wave shadowing because of the traveling straight of a electric wave. In such inferior communication environment, it constructed the stabilized communication link that can do collecting and servicing the correct traffic information and designed the beam pattern considering the establishment position of the antenna that can apply to various road environments and a communication area. By considering the communication link environment, this paper designed and manufacture the mean frequency of 5.8GHz, the input loss of -17dB in 75MHz bandwidth, the Axial ratio of 1.5:1, and $2{\times}4$ array microstrip antenna which beam pattern have the characteristic of $55^{\circ}$ horizontal half power beam width and $26^{\circ}$elevation half power beam width and the minimum establishment height of the antenna was designed as 14m for avoiding electric wave shadowing on a physical condition between vehicles

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.1
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• pp.77-88
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• 2000

In this paper, the 3-mode variable gain high power amplifier for a transmitter of INMARSAT-B operating at L-band(1626.5-1646.5 MHz) was developed. This SSPA can amplify 42 dBm in high power mode, 38 dBm in medium power mode and 36 dBm in low power mode for INMARSAT-B. The allowable errol sets +1 dBm as the upper limit and -2 dBm as the lower limit, respectively. To simplify the fabrication process, the whole system is designed by two parts composed of a driving amplifier and a high power amplifier. The HP's MGA-64135 and Motorola's MRF-6401 were used for driving amplifier, and the ERICSSON's PTE-10114 and PTF-10021 for the high power amplifier. The SSPA was fabricated by the RP circuits, the temperature compensation circuits and 3-mode variable gain control circuits and 20 dB parallel coupled-line directional coupler in aluminum housing. In addition, the gain control method was proposed by digital attenuator for 3-mode amplifier. Then il has been experimentally verified that the gain is controlled for single tone signal as well as two tone signals. In this case, the SSPA detects the output power by 20 dB parallel coupled-line directional coupler and phase non-splitter amplifier. The realized SSPA has 41.6 dB, 37.6 dB and 33.2 dB for small signal gain within 20 MHz bandwidth, and the VSWR of input and output port is less than 1.3:1. The minimum value of the 1 dB compression point gets more than 12 dBm for 3-mode variable gain high power amplifier. A typical two tone intermodulation point has 36.5 dBc maximum which is single carrier backed off 3 dB from 1 dB compression point. The maximum output power of 43 dBm was achieved at the 1636.5 MHz. These results reveal a high power of 20 Watt, which was the design target.