Hee-jin Lee

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CDMA/HDR system is designed to provide High Data Rate services in the cellular networks compatible with IS-95B CDMA network. It uses a PF(Proportional Fairness) scheduler that improves total throughput by using multi-user diversity in a forward link while supporting user’s average throughput proportional to channel conditions. Therefore, PFS does not(More)
Abstract: In this paper, we propose a direct model reference adaptive fuzzy control (MRAFC) for MIMO nonlinear systems whose structure is represented by the Takagi-Sugeno fuzzy model. The adaptive law of the MRAFC estimates the approximation error of the fuzzy logic system so that it provides asymptotic tracking of the reference signal for the systems with(More)
In this paper, optical wireless communication systems based on a controller area network (CAN) are proposed and demonstrated. The optical transceiver is composed of 25 LED's array around plus 3 PDs in the center and two CAN transceivers. By means of that, the conventional two-wired CAN bus replaces to the free-space optical channels. To ensure the(More)
Realtime and embedded systems may be left on unexpected states because system's user can generate some incident events in various conditions. Although the UML 2.0 sequence diagrams recently incorporate several modelling features for embedded software, they have some difficulties to depict unexpected behaviours of embedded software conveniently. In this(More)
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